Consumption of dairy products and associations with incident diabetes, CHD and mortality in the Whitehall II study

Yogurt and Reduced Risk of Type 2 Diabetes: Exploring the FDA Qualified Health Claim and Potential Implications for Improving Public Health

Type 2 diabetes (T2D) is a significant public health burden in the U.S. today. As the incidence is predicted to increase, advancing our understanding of food-based recommendations that reduce the risk of T2D is critical to improve public health. Over the past two decades, a body of scientific evidence has emerged demonstrating the association between consumption of dairy yogurt and reduced risk of T2D. This culminated in 2024, with the decision of the U.S. Food and Drug Administration (FDA) to announce a qualified health claim on the consumption of yogurt and reduced T2D risk. Qualified health claims enable specific messaging on the role that a food may play in mediating disease risk. As yogurt is a component of the under-consumed Dairy food group within the Dietary Guidelines for Americans (DGAs), communication on the relationship between yogurt and T2D risk can help encourage the public to increased intake of yogurt and with it, nutrients of public health concern such as calcium. The key research included in the FDA enforcement discretion letter and Evidence-Based Review is outlined. This Perspective illustrates the outcome of multi-sector work that includes scientific researchers, nonprofit and industry partners, and policymakers in the development and activation of science-based public health messaging.

Association of dietary live microbe intake with all-cause and cardiovascular mortality in an older population: Evidence from NHANES 2003-2018

BACKGROUND

The relationship between dietary live microbe intake, non-dietary prebiotics/probiotics, and mortality in older adults remains unclear.

METHODS

Participants from the National Health and Nutrition Examination Survey 2003-2018 were included. Participants were categorized into three groups based on estimated live microbe intake: low, medium, and high. Additionally, they were divided by their consumption of foods with medium or high microbial content. Text mining was employed to identify the use of non-dietary prebiotics and probiotics by analyzing the names and ingredients of dietary supplements and drugs. Associations between live microbe intake, non-dietary prebiotics/probiotics, and all-cause or cardiovascular mortality were assessed using Kaplan-Meier survival curves and Cox regression models. Inverse Probability of Treatment Weighting was used for sensitivity analysis RESULT: A total of 7882 participants were included in the study. During a mean follow-up of 8.08 years, all-cause mortality was 18 % lower in older adults with high dietary live microbe intake in fully adjusted models (HR, 0.82; 95 %CI 0.70-0.96), and cardiovascular mortality was reduced by 23 % (HR, 0.77; 95 %CI 0.61-0.98). The risk of all-cause mortality was reduced by 21 % in the G3 group compared with the G1 group (HR, 0.79; 95 % CI 0.69-0.89) and a 29 % reduction in the risk of cardiovascular disease-specific death (HR, 0.71;95 %CI 0.59-0.86). In addition, we also observed that nondietary prebiotic and probiotic supplement intake was also associated with a reduced risk of mortality in an older US population.

CONCLUSION

In older U.S. adults, higher dietary live microorganisms and non-dietary probiotics/prebiotics intake was associated with a reduced risk of all-cause and cardiovascular mortality.

The association between consumption of dairy products and risk of type 2 diabetes

Background

The effects of dairy products on type 2 diabetes mellitus (T2DM) are unclear. Some studies have revealed the beneficial effects, whereas others found harmful effects of dairy products on the risk of T2DM. The objective of the present study was to investigate the association of different types of dairy products with risk of T2DM in Iranian adults.

Methods

This cross-sectional study included a total of 4241 individuals. Among these participants, 1804 were diagnosed with T2DM or prediabetes, whereas the remaining 2437 individuals were without T2DM. A validated food frequency questionnaire was used to assess the consumption of different types of dairy products.

Results

A positive association was found between T2DM with dietary intake of milk [odds ratio (OR): 1.16, 95% confidence interval (CI): 1.11-1.23, P = 0.008] and cheese (OR: 1.90, 95% CI: 1.41-2.29, P = 0.001) after adjustment for age, sex, physical activity, BMI, education level, energy, and fat intake. There was no significant association between T2DM and dietary intake of total dairy, yogurt, ayran (yogurt drink), and curd.

Conclusion

A positive association was found between the consumption of some dairy products including milk and cheese and the risk of T2DM. Further longitudinal studies are warranted to approve this finding.

A global analysis of dairy consumption and incident cardiovascular disease

The role of dairy products in cardiovascular disease (CVD) prevention remains controversial. This study investigates the association between dairy consumption and CVD incidence using data from the China Kadoorie Biobank and the UK Biobank, complemented by an updated meta-analysis. Among Chinese participants, regular dairy consumption (primarily whole milk) is associated with a 9% increased risk of coronary heart disease (CHD) and a 6% reduced risk of stroke compared to non-consumers. Among British participants, total dairy consumption is linked to lower risks of CVD, CHD, and ischemic stroke, with cheese and semi-skimmed/skimmed milk contributing to reduced CVD risk. Meta-analysis reveals that total dairy consumption is associated with a 3.7% reduced risk of CVD and a 6% reduced risk of stroke. Notably, inverse associations with CVD incidence are observed for cheese and low-fat dairy products. Current evidence suggests that dairy consumption, particularly cheese, may have protective effects against CVD and stroke.

Dietary Live Microbes Intake Associated With Biological Aging and Mortality

This observational study aimed to investigate associations between dietary live microbe intake and mortality, as well as biological aging. Adults from the 1999-2018 National Health and Nutrition Examination Survey were categorized into low, medium, and high dietary live microbe groups. Foods with medium and high live microbe content were aggregated into a medium-high consumption category. The outcomes included all-cause, cardiovascular, and cancer mortality, along with biological age (BA) acceleration assessed by the Klemera-Doubal method (KDM) and PhenoAge. Multiple regression analyses and mediation analyses were conducted to assess associations, adjusting for potential confounders. A total of 34 133 adults were included in our analyses. Over an average follow-up period of 9.92 years, 5 462 deaths occurred. In multivariate adjusted models, every 100 g of medium-high group foods consumed was associated with reduced all-cause mortality (hazard ratio [HR] 0.94, 95% confidence interval [CI] 0.91 to 0.97, p < .001) and cardiovascular mortality (HR 0.91, 95% CI 0.86 to 0.96, p < .001), but not with cancer mortality (HR 1.01, 95% CI 0.95 to 1.07, p = .768). Every 100 g medium-high group foods consumption was associated with decreased KDM-BA acceleration (fully adjusted regression coefficient -0.09, 95% CI -0.15 to -0.04, p = .001) and PhenoAge acceleration (fully adjusted regression coefficient -0.07, 95% CI -0.11 to -0.03, p < .001). Mediation analysis showed that BA acceleration partially mediated live microbes-mortality associations. Our results suggest that higher dietary live microbe intake is associated with lower mortality risk and slower biological aging. However, further research is needed to verify these findings.

Dietary phytochemical index and its relationship with diabetic sensorimotor polyneuropathy: a case-control study

Phytochemicals are compounds found in fruits, vegetables, whole grains, nuts and legumes that are non-nutritive but have bioactive properties. A high intake of these compounds is essential for optimal health and disease prevention. No study has investigated the association between Dietary Phytochemical Index (DPI) and polyneuropathy in patients with diabetes. This study aimed to examine the association between DPI and Diabetic Sensory-motor Polyneuropathy (DSPN) in a case-control study. In this case-control study, a total of 185 diabetic patients with DSPN (case group) and 185 sex- and age-matched diabetic patients without neuropathy (control group) were enrolled in this study. Participants were 30-60 years old. A validated food frequency questionnaire was used to measure the dietary intake of all participants. Daily energy derived from phytochemical-rich foods was used to calculate the DPI score. Toronto clinical neuropathy score was applied to define DSPN. Anthropometric data and fasting blood glucose levels were measured using standard methods. The Binary logistic regression was used to estimate Crude and multivariable-adjusted OR (95% CI) for DSPN across tertiles of DPI for the whole population. In the crude model, there was a significant trend across the tertile of DPI (OR highest vs. lowest tertile of DPI = 0.33; 95%CI 0.18, 0.52; P-trend < 0.001). After controlling for age, sex, and energy, a significant reverse association was observed between DPI and DSPN (OR highest vs. lowest tertile of DPI = 0.27; 95%CI 0.15, 0·48; P-trend < 0.001). Moreover, after adjusting for a wide range of confounding variables such as energy intake, physical activity, education, smoking status, and HbA1c, participants in the third tertile of DPI had 75% reduced odds for DSPN (95%CI 0.14, 0.45; P-trend < 0.001). Finally in the full adjusted model, after further adjustment for BMI, observed significant association was remained (OR highest vs. lowest tertile of DPI: 0.24; 95% CI 0.13, 0.14; P-trend < 0.001). Higher intakes of phytochemical-rich foods are associated with lower odds of DSPN.

Dietary Habits, Physical Activity and Body Mass Index in Transgender and Gender Diverse Adults in Italy: A Voluntary Sampling Observational Study

Transgender and gender-diverse (TGD) individuals continue to experience harassment and discrimination across various aspects of life, significantly impacting their physical and mental health. The scarcity of data on their general health, particularly regarding dietary habits, remains a challenge in developing effective healthcare strategies for this population. To address this gap, we analyzed selected dietary habits, physical activity (PA), and body mass index (BMI) among Italian TGD adults compared to the Italian general population (IGP). An online anonymous survey was conducted via the Computer Assisted Web Interviewing technique from June 2020 to June 2021. Participants were enrolled through clinical centers and TGD organizations. Data from 959 TGD adults were analyzed using chi-squared tests and logistic regression models. Key findings indicated that approximately 70% of TGD individuals consumed fewer servings of fruit and vegetables (FV) than recommended (five or more servings per day). Although red meat consumption was lower overall, a greater percentage of TGD individuals reported consuming more than three servings per week. Additionally, 58% of TGD participants indicated that they did not engage in any PA, compared to 36% of the IGP. Notably, significant differences in BMI were identified, with higher rates of overweight and obesity among TGD individuals assigned female at birth. These results underscore the urgent need for tailored nutritional guidelines and inclusive public health strategies to meet the specific health needs of the Italian TGD population. Expanding access to targeted interventions could contribute to improving overall well-being in this marginalized group.

Adherence to Mediterranean dietary pattern and the risk of gestational diabetes mellitus: a systematic review and meta-analysis of observational studies

BACKGROUND AND AIM

Gestational diabetes mellitus (GDM) is one of the most prevalent disorders occurring during pregnancy, which confers significant risk of short and long-term adverse outcomes in both mothers and offspring. Recently, more attention has been paid to the association of pre-pregnancy and early pregnancy healthy dietary patterns, such as Mediterranean dietary pattern with GDM. However, there is a lack of systematic review and meta-analysis summarizing findings in this regard. Hence, we sought to assess the association of MedDiet and GDM in observational studies by performing a systematic review and meta-analysis.

METHODS

A comprehensive systematic literature search of observational studies was conducted via PubMed, Scopus, and Google Scholar, up to August 2023. Studies were included in our review if they evaluated the association of MedDiet and GDM, following an observational study design.

RESULTS

Ten studies were included in this study. Combining effect sizes, we found that adherence to MedDiet was inversely associated with GDM risk (OR = 0.64; CI: 0.52-0.78); implying that higher adherence to the MedDiet could reduce the risk of GDM by about 36%. Stratification by the geographic area, Mediterranean countries, time of dietary assessment and study design, showed a consistent significant association between MedDiet and GDM.

CONCLUSION

We conclude that adhering to diets resembling MedDiet, before or in early pregnancy, could be associated with lower risks or odds of GDM.

A new era for food in health? The FDA announces a qualified health claim for yogurt intake and type 2 diabetes mellitus risk reduction

INTRODUCTION

Over the last two decades research has grown regarding dairy intake and health. It has been reported by many that yogurt intake may be associated with reduced risk of type 2 diabetes mellitus (T2D). In this report, the United States Food and Drug Administration (FDA) decision to announce a qualified health claim for yogurt products regarding reduced risk of T2D in response to a Danone North America petition is discussed.

METHODS

Relevant literature cited in the petition along with supporting evidence from PubMed and Google Scholar databases until April 1st, 2024 were used. Literature was found using relevant keywords.

RESULTS

On March 1st, 2024, the United States Food and Drug Administration (FDA) announced the first ever qualified health claim, stating that eating yogurt regularly may reduce the risk of T2D according to limited scientific evidence. The enforcement discretion letter was critically reviewed and discussed regarding its future implications for people with T2M and public health.

CONCLUSIONS

It is unclear how this FDA decision will affect public health and nutrition in the long-term. Limited scientific evidence suggests that at least 3 servings of yogurt per week may reduce the risk of T2D incidence for the general population. Yogurt will not cure or treat people with T2D.

Cheese consumption and multiple health outcomes: an umbrella review and updated meta-analysis of prospective studies

This umbrella review aims to provide a systematic and comprehensive overview of current evidence from prospective studies on the diverse health effects of cheese consumption. We searched PubMed, Embase, and Cochrane Library to identify meta-analyses/pooled analyses of prospective studies examining the association between cheese consumption and major health outcomes from inception to August 31, 2022. We reanalyzed and updated previous meta-analyses and performed de novo meta-analyses with recently published prospective studies, where appropriate. We calculated the summary effect size, 95% prediction confidence intervals, between-study heterogeneity, small-study effects, and excess significance bias for each health outcome. We identified 54 eligible articles of meta-analyses/pooled analyses. After adding newly published original articles, we performed 35 updated meta-analyses and 4 de novo meta-analyses. Together with 8 previous meta-analyses, we finally included 47 unique health outcomes. Cheese consumption was inversely associated with all-cause mortality (highest compared with lowest category: RR = 0.95; 95% CI: 0.92, 0.99), cardiovascular mortality (RR = 0.93; 95% CI: 0.88, 0.99), incident cardiovascular disease (CVD) (RR = 0.92; 95% CI: 0.89, 0.96), coronary heart disease (CHD) (RR = 0.92; 95% CI: 0.86, 0.98), stroke (RR = 0.93; 95% CI: 0.89, 0.98), estrogen receptor-negative (ER-) breast cancer (RR = 0.89; 95% CI: 0.82, 0.97), type 2 diabetes (RR = 0.93; 95% CI: 0.88, 0.98), total fracture (RR = 0.90; 95% CI: 0.86, 0.95), and dementia (RR = 0.81; 95% CI: 0.66, 0.99). Null associations were found for other outcomes. According to the NutriGrade scoring system, moderate quality of evidence was observed for inverse associations of cheese consumption with all-cause and cardiovascular mortality, incident CVD, CHD, and stroke, and for null associations with cancer mortality, incident hypertension, and prostate cancer. Our findings suggest that cheese consumption has neutral to moderate benefits for human health.

Yogurt consumption and risk of mortality from all causes, CVD and cancer: a comprehensive systematic review and dose-response meta-analysis of cohort studies

OBJECTIVES

To quantify the dose-response relation between yogurt consumption and risk of mortality from all causes, CVD and cancer.

DESIGN

Systematic review and meta-analysis.

SETTING

We conducted a comprehensive search of PubMed/Medline, ISI Web of Science and Scopus databases through August 2022 for cohort studies reporting the association of yogurt consumption with mortality from all causes, CVD and cancer. Summary relative risks (RR) and 95 % CI were calculated with a random-effects model.

PARTICIPANTS

Seventeen cohort studies (eighteen publications) of 896 871 participants with 75 791 deaths (14 623 from CVD and 20 554 from cancer).

RESULTS

High intake of yogurt compared with low intake was significantly associated with a lower risk of deaths from all causes (pooled RR 0·93; 95 % CI: 0·89, 0·98, I2 = 47·3 %, n 12 studies) and CVD (0·89; 95 % CI: 0·81, 0·98, I2 = 33·2 %, n 11), but not with cancer (0·96; 95 % CI: 0·89, 1·03, I2 = 26·5 %, n 12). Each additional serving of yogurt consumption per d was significantly associated with a reduced risk of all-cause (0·93; 95 % CI: 0·86, 0·99, I2 = 63·3 %, n 11) and CVD mortality (0·86; 95 % CI: 0·77, 0·99, I2 = 36·6 %, n 10). There was evidence of non-linearity between yogurt consumption and risk of all-cause and CVD mortality, and there was no further reduction in risk above 0·5 serving/d.

CONCLUSION

Summarising earlier cohort studies, we found an inverse association between yogurt consumption and risk of all-cause and CVD mortality; however, there was no significant association between yogurt consumption and risk of cancer mortality.

Gut microbiome and cancer implications: Potential opportunities for fermented foods

There is a critical opportunity to improve response to immunotherapies and overall cancer survivorship via dietary interventions targeted to modify the gut microbiome, and in turn, potentially enhance anti-cancer immunity. A promising dietary intervention is fermented foods, which may alter gut microbiome composition and, in turn, improve immunity. In this article, we summarize the state of the literature pertaining to the gut microbiome and response to immunotherapy and other cancer treatments, potential clinical implications of utilizing a fermented foods dietary approach to improve cancer treatment outcomes, and existing gaps in the literature regarding the implementation of fermented food interventions among individuals with cancer or with a history of cancer. This review synthesizes a compelling rationale across different disciplines to lay a roadmap for future fermented food dietary intervention research aimed at modulating the gut microbiome to reduce cancer burden.

Association of Fermented Products with Risk of Cancer Recurrence and Mortality among Breast Cancer Survivors: A Prospective Cohort Study

We hypothesized that the intake of fermented soy and dairy products, but not fermented vegetable products, was associated with reduced cancer recurrence and mortality in breast cancer survivors. Women (n = 606) who underwent dietary survey using a 24-h recall within 3 years of breast cancer surgery were recruited, and were followed up for a mean of 89 mo,. Cox proportional hazards regression analysis showed that the risk of cancer recurrence was inversely associated with the intake of fermented soy products (Hazard ratios (HRs):0.976, 95% confidence intervals (CI):0.95-0.99) and fermented dairy products (HRs:0.992, 95% CI:0.98-0.99). Furthermore, the risk of cancer recurrence was inversely associated with the intake of fermented soy products in hormone receptor-positive (HRs:0.296, 95% CI:0.11-0.79), estrogen receptor-positive (HRs:0.971, 95% CI:0.94-0.99), and progesterone receptor-positive (HRs:0.972, 95% CI:0.94-0.99) patients. Mortality was inversely associated with the intake of fermented soy products (HRs:0.967, 95% CI:0.93-0.99). Disease-free survival (P = 0.001) and overall survival (P = 0.004) were positively associated with intake of fermented soy products. Intake of fermented vegetable products had no significant effect on cancer recurrence or mortality. This study suggests that the intake of fermented soy and dairy could be beneficial in preventing cancer recurrence.

Consumption of Dairy Products and the Risk of Overweight or Obesity, Hypertension, and Type 2 Diabetes Mellitus: A Dose-Response Meta-Analysis and Systematic Review of Cohort Studies

Dairy products have been suggested to be related to the prevention of overweight or obesity, hypertension, and type 2 diabetes mellitus (T2DM). These associations are currently controversial, however, and a systematic quantitative meta-analysis is lacking. In this study, we examined the associations between dairy products and the risk of overweight or obesity, hypertension, and T2DM and tested for dose-response relations. We comprehensively searched PubMed, Embase, and Web of Science up to April 2021. Cohort studies were included if dairy food consumption was reported at a minimum of 3 levels or as continuous variables, and the associations were assessed with overweight or obesity, hypertension, and T2DM. Summary RRs and 95% CIs were estimated for the dose-response association. Restricted cubic splines were used to evaluate the linear or nonlinear relations. Among the 9887 articles retrieved, 42 articles were included. For overweight or obesity, a linear association was observed for total dairy, milk, and yogurt. The risk decreased by 25%, 7%, and 12% per 200-g/d increase for total dairy, high-fat dairy, and milk, respectively, and by 13% per 50-g/d increment of yogurt. For hypertension, a nonlinear association was observed with total dairy, whereas significant inverse associations were found for low-fat dairy (RR: 0.94; 95% CI: 0.90, 0.98) and milk (RR: 0.94; 95% CI: 0.92, 0.97) per 200-g/d intake increase. For T2DM, all types of dairy food consumption except for milk and low-fat dairy products showed nonlinear associations, with total dairy and yogurt intake associated with 3% and 7% lower risk per 200-g/d and 50-g/d intake increase, respectively. In conclusion, our study suggests that total dairy is associated with a low risk of overweight or obesity, hypertension, and T2DM, especially milk and yogurt for overweight or obesity, low-fat dairy and milk for hypertension, and yogurt for T2DM.

Traditional Fermented Foods and Beverages from around the World and Their Health Benefits

Traditional fermented foods and beverages play an important role in a range of human diets, and several experimental studies have shown their potential positive effects on human health. Studies from different continents have revealed strong associations between the microorganisms present in certain fermented foods (e.g., agave fructans, kefir, yeats, kombucha, chungkookjang, cheeses and vegetables, among others) and weight maintenance, reductions in the risk of cardiovascular disease, antidiabetic and constipation benefits, improvement of glucose and lipids levels, stimulation of the immunological system, anticarcinogenic effects and, most importantly, reduced mortality. Accordingly, the aim of this review is to corroborate information reported in experimental studies that comprised interventions involving the consumption of traditional fermented foods or beverages and their association with human health. This work focuses on studies that used fermented food from 2014 to the present. In conclusion, traditional fermented foods or beverages could be important in the promotion of human health. Further studies are needed to understand the mechanisms involved in inflammatory, immune, chronic and gastrointestinal diseases and the roles of fermented traditional foods and beverages in terms of preventing or managing those diseases.

Underlying evidence for the health benefits of fermented foods in humans

Fermented foods (FFs) have been a part of our diets for millennia and comprise highly diverse products obtained from plants and animals all over the world. Historically, fermentation has been used to preserve food and render certain raw materials edible. As our food systems evolve towards more sustainability, the health benefits of FFs have been increasingly touted. Fermentation generates new/transformed bioactive compounds that may occur in association with probiotic bacteria. The result can be specific, advantageous functional properties. Yet, when considering the body of human studies on the topic, whether observational or experimental, it is rare to come across findings supporting the above assertion. Certainly, results are lacking to confirm the widespread idea that FFs have general health benefits. There are some exceptions, such as in the case of lactose degradation via fermentation in individuals who are lactose intolerant; the impact of select fermented dairy products on insulin sensitivity; or the benefits of alcohol consumption. However, in other situations, the results fail to categorically indicate whether FFs have neutral, beneficial, or detrimental effects on human health. This review tackles this apparent incongruity by showing why it is complex to test the health effects of FFs and what can be done to improve knowledge in this field.

Fermented Foods, Health and the Gut Microbiome

Fermented foods have been a part of human diet for almost 10,000 years, and their level of diversity in the 21st century is substantial. The health benefits of fermented foods have been intensively investigated; identification of bioactive peptides and microbial metabolites in fermented foods that can positively affect human health has consolidated this interest. Each fermented food typically hosts a distinct population of microorganisms. Once ingested, nutrients and microorganisms from fermented foods may survive to interact with the gut microbiome, which can now be resolved at the species and strain level by metagenomics. Transient or long-term colonization of the gut by fermented food strains or impacts of fermented foods on indigenous gut microbes can therefore be determined. This review considers the primary food fermentation pathways and microorganisms involved, the potential health benefits, and the ability of these foodstuffs to impact the gut microbiome once ingested either through compounds produced during the fermentation process or through interactions with microorganisms from the fermented food that are capable of surviving in the gastro-intestinal transit. This review clearly shows that fermented foods can affect the gut microbiome in both the short and long term, and should be considered an important element of the human diet.

Association of Yogurt and Dietary Supplements Containing Probiotic Consumption With All-Cause and Cause-Specific Mortality in US Adults: A Population-Based Cohort Study

Background

Although probiotic intake had beneficial effects on several specific disorders, limited evidence was available about the benefits of probiotic intake in the general population. This study aimed to evaluate the relationship between yogurt (as a natural probiotic source) and dietary supplements containing probiotic consumption and mortality in US adults.

Methods

We conducted an observational cohort study comprised of a nationally representative sample of adults who were enrolled in the National Health and Nutrition Examination Survey (NHANES) between 1999 and 2014. Individuals were linked to the US National Death Index.

Results

We included 32,625 adults in our study. Of the study cohort, 3,539 participants had yogurt consumption, 213 had dietary supplements containing probiotic consumption, and the remaining participants (28,873) did not have yogurt and/or dietary supplements containing probiotic consumption. During 266,432 person-years of follow-up, 3,881 deaths from any cause were ascertained, of which 651 were due to cardiovascular disorders and 863 were due to cancer. Weighted Cox proportional hazards models suggested that yogurt consumption was inversely associated with all-cause mortality (adjusted hazard ratio (HR), 0.83 [95% confidence interval (CI), 0.71–0.98]) but not cardiovascular mortality (adjusted HR, 0.68 [95%CI, 0.43–1.08]) and cancer mortality (adjusted HR, 1.00 [95%CI, 0.72–1.38]). However, dietary supplements containing probiotic were not associated with decreased all-cause and cause-specific mortality.

Conclusions

The present study suggested that yogurt consumption was associated with a lower risk of all-cause mortality among U.S. adults. Yogurt consumption in diet might be a sensible strategy for reducing the risk of death.

Dose-response relationships between dairy intake and non-communicable chronic diseases: an NHANES-based cross-sectional study

The purpose of this study was to explore the possible association between dairy and NCDs and identify possible dairy types that could lower the odds of NCDs. Data were from the 2003-2016 NHANES, a cross-sectional study with 20,297 adults. Multivariable logistic regression analyses and restricted cubic spline (RCS) models were conducted. In the highest intake group (>250 g/d, 1 daily serving), yogurt and milk were inversely associated with the odds of general obesity and central obesity [OR (95% CI), general obesity, 0.74 (0.60-0.91) and 0.75 (0.68-0.83); central obesity, 0.70 (0.56-0.87), and 0.77 (0.70-0.86), respectively, p < 0.05]. Higher milk intake is inversely associated with diabetes, and higher cream intake is associated with a lower likelihood of hyperlipidaemia. The intake of yogurt, milk, cheese, and butter was 0-308 g/d (0-1.2 daily servings), 0-887 g/d (0-3.5 daily servings), <75 g/d (1.7 daily servings), and <15 g/d (0.5 daily servings), respectively.

Association of dairy intake with all-cause, cancer, and cardiovascular disease mortality in Japanese adults: a 25-year population-based cohort

PURPOSE

The association between dairy intake and mortality remains uncertain, and evidence for the Japanese population is scarce. We aimed to investigate the association between dairy intake and all-cause, cancer, and cardiovascular disease (CVD) mortality in Japanese adults.

METHODS

A total of 34,161 participants (16,565 men and 17,596 women) aged 40-64 years without a history of cancer, myocardial infarction, or stroke at baseline were included in the analysis, using data from the Miyagi Cohort Study initiated in 1990. Milk, yogurt, and cheese intake were obtained using a validated food frequency questionnaire. Total dairy intake was calculated as the sum of milk, yogurt, and cheese intake and then categorized by quartile. The outcomes were all-cause, cancer, and CVD mortality. Cox proportional hazards regression models were used to estimate multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality risks.

RESULTS

During 750,016 person-years of follow-up, the total number of deaths was 6498, including 2552 deaths due to cancer and 1693 deaths due to CVD. There was no association between total dairy intake and all-cause, cancer, and CVD mortality for both men and women. We also examined the associations between subgroup dairy products and mortality. For milk and yogurt intake, our results suggest null associations. However, cheese intake was modestly associated with lower all-cause mortality in women; compared with non-consumers, the multivariable HRs (95%CIs) were 0.89 (0.81-0.98) for 1-2 times/month, 0.88 (0.78-1.00) for 1-2 times/week, and 0.89 (0.74-1.07) for 3 times/week or almost daily (p trend = 0.016).

CONCLUSION

Dairy intake was not associated with mortality in Japanese adults, except for limited evidence showing a modest association between cheese intake and a lower all-cause mortality risk in women.

Seaweeds as a Fermentation Substrate: A Challenge for the Food Processing Industry

Seaweeds are gaining momentum as novel and functional food and feed products. From whole consumption to small bioactive compounds, seaweeds have remarkable flexibility in their applicability, ranging from food production to fertilizers or usages in chemical industries. Regarding food production, there is an increasing interest in the development of novel foods that, at the same time, present high nutritious content and are sustainably developed. Seaweeds, because they require no arable land, no usage of fresh water, and they have high nutritious and bioactive content, can be further explored for the development of newer and functional food products. Fermentation, especially performed by lactic acid bacteria, is a method used to produce functional foods. However, fermentation of seaweed biomass remains an underdeveloped topic that nevertheless demonstrates high potential for the production of new alimentary products that hold and further improve the organoleptic and beneficial properties that these organisms are characterized for. Although further research has to be deployed in this field, the prebiotic and probiotic potential demonstrated by fermented seaweed can boost the development of new functional foods.

Dairy Product Consumption and Cardiovascular Health: a Systematic Review and Meta-Analysis of Prospective Cohort Studies

The association between dairy product consumption and cardiovascular health remains highly debated. We quantitatively synthesized prospective cohort evidence on the associations between dairy consumption and risk of hypertension (HTN), coronary heart disease (CHD) and stroke. We systematically searched PubMed, Embase, and Web of Science through August 1st, 2020 to retrieve prospective cohort studies that reported on dairy consumption and risk of HTN, CHD or stroke. We used random-effects models to calculate the pooled relative risk (RR) and 95% confidence interval (CI) for the highest vs the lowest category of intake and for 1 serving/day increase in consumption. We rated the quality of evidence using NutriGrade. Fifty-five studies were included. Total dairy consumption was associated with a lower risk of HTN (RR for highest vs lowest level of intake: 0.91, 95% CI: 0.86-0.95, I2 = 73.5%; RR for 1 serving/day increase: 0.96, 95% CI: 0.94-0.97, I2 = 66.5%), CHD (highest vs lowest level of intake: 0.96, 95% CI: 0.92-1.00, I2 = 46.6%; 1 serving/day increase: 0.98, 95% CI: 0.95-1.00, I2 = 56.7%), and stroke (highest vs lowest level of intake: 0.90, 95% CI: 0.85-0.96, I2 = 60.8%; 1 serving/day increase: 0.96, 95% CI: 0.93-0.99, I2 = 74.7%). Despite moderate to considerable heterogeneity, these associations remained consistent across multiple subgroups. Evidence on the relationship between total dairy and risk of HTN and CHD were of moderate quality and of low quality for stroke. Low-fat dairy consumption was associated with lower risk of HTN and stroke, and high-fat dairy with a lower risk of stroke. Milk, cheese, or yogurt consumption showed inconsistent associations with the cardiovascular outcomes in high vs. low intake and dose-response meta-analyses. Total dairy consumption was associated with a modestly lower risk of hypertension, CHD and stroke. Moderate to considerable heterogeneity was observed in the estimates and the overall quality of the evidence was low to moderate.

Theoretical substitutions between dairy products and all-cause and cause-specific mortality. Results from the Danish diet, cancer and health cohort

A daily intake of dairy products is recommended in many countries in order to maintain optimal health throughout life. However, evidence regarding the association between intake of individual dairy products and mortality is limited. We therfore, explored associations between intake of different dairy products and all-cause and cause-specific mortality using specified theoretical substitution analyses. We analysed data from 55 775 Danish men and women aged 50-64 years between 1993 and 1997. Information about dairy product intake at baseline was collected using a validated food frequency questionnaire. Information about vital status and causes of death was obtained through national registers. Measures of associations were calculated using Cox proportional hazards regression. During a median follow-up of 19·0 years, 11 586 participants died. For all-cause mortality, we observed that the intake of low-fat milk, whole-fat milk or low-fat yogurt products in place of cheese was associated with a higher rate of death (hazard ratios between 1·03 and 1·12 per serving/d substituted). The same pattern was present for CVD mortality. For cancer mortality, whole-fat milk and low-fat yogurt products in place of cheese were also associated with a higher rate of death for men while for women, whole-fat milk in place of buttermilk was associated with a higher cancer mortality rate. The results appeared robust in several sensitivity analyses. Our results suggest that intake of low-fat milk, whole-fat milk or low-fat yogurt products in place of cheese is associated with a higher rate of all-cause and cause-specific mortality.

Evaluation of glycemic index, antioxidant capacity, and metabolic effects of a fermented beverage made from Changbai Mountain fruit and vegetables

Fermented foods and beverages have been known to be beneficial when included in the human diet. This study examined the glycemic index (GI) of a fermented beverage (FB) made from Changbai Mountain fruit and vegetables in humans and its antioxidant capacity and metabolic effects in a rat model of diabetes. Twenty healthy volunteers were tested with 50 g of glucose and 50 g equivalent of carbohydrates from FB on two separate days for GI measurement. The rats were randomly divided into blank control group (n = 15) and diabetic model (DM) group (n = 75). DM group were randomly divided into five groups, positive control group, model control group and three FB treatment (2.5, 5, 10 ml/kg·bw·d) groups. The general indices, including blood glucose and lipid levels and antioxidant index, of the rats were measured to investigate the effect of FB. The GI of FB was found to be 56.99, indicating it as a medium GI food. Compared to model control group, the low-dose FB group had lower blood glucose levels and higher high-density lipoprotein cholesterol levels in DM rats (p < .05). Medium- and high-dose FB decreased the serum malonaldehyde levels in DM rats compared to those in the model control group. The FB-treated DM rat groups showed increased serum glutathione and superoxide dismutase levels compared with those in the model control group (p < .05). FB is a medium GI food that plays a protective role against oxidative stress in DM rats. PRACTICAL APPLICATIONS: The present study evaluated the glycemic index of a fermented beverage (FB) made from Changbai Mountain fruit and vegetables in humans and investigated its antioxidant capacity and metabolic effects in a rat diabetes model. The study results may aid in the development of FB from fruits and vegetables and provide a theoretical basis for further research and development.

Yogurt, cultured fermented milk, and health: a systematic review

Consumption of yogurt and other fermented products is associated with improved health outcomes. Although dairy consumption is included in most dietary guidelines, there have been few specific recommendations for yogurt and cultured dairy products. A qualitative systematic review was conducted to determine the effect of consumption of fermented milk products on gastrointestinal and cardiovascular health, cancer risk, weight management, diabetes and metabolic health, and bone density using PRISMA guidelines. English language papers in PubMed were searched, with no date restrictions. In total, 1057 abstracts were screened, of which 602 were excluded owing to lack of appropriate controls, potential biases, and experimental design issues. The remaining 455 papers were independently reviewed by both authors and 108 studies were included in the final review. The authors met regularly to concur, through consensus, on relevance, methods, findings, quality, and conclusions. The included studies were published between 1979 and 2017. From the 108 included studies, 76 reported a favorable outcome of fermented milks on health and 67 of these were considered to be positive or neutral quality according to the Academy of Nutrition and Dietetics’ Quality Criteria Checklist. Of the 32 remaining studies, the study outcomes were either not significant (28) or unfavorable (4), and most studies (18) were of neutral quality. A causal relationship exists between lactose digestion and tolerance and yogurt consumption, and consistent associations exist between fermented milk consumption and reduced risk of breast and colorectal cancer and type 2 diabetes, improved weight maintenance, and improved cardiovascular, bone, and gastrointestinal health. Further, an association exists between prostate cancer occurrence and dairy product consumption in general, with no difference between fermented and unfermented products. This article argues that yogurt and other fermented milk products provide favorable health outcomes beyond the milk from which these products are made and that consumption of these products should be encouraged as part of national dietary guidelines.

Systematic review registration: PROSPERO registration no. CRD42017068953.

Intake of dairy products and associations with major atherosclerotic cardiovascular diseases: a systematic review and meta-analysis of cohort studies

Specific types of dairy products may be differentially associated with atherosclerotic cardiovascular disease (CVD). We conducted a systematic review and meta-analysis of cohort studies to summarize findings on the associations between total dairy product intake and intake of dairy product subgroups and the risk of major atherosclerotic CVDs in the general adult population. Our protocol was registered in PROSPERO (CRD42019125455). PubMed and Embase were systematically searched through 15 August 2019. For high versus low intake and dose-response meta-analysis, random-effects modelling was used to calculate summary risk ratios (RR). There were 13 cohort studies included for coronary heart disease (CHD), 7 for ischemic stroke and none for peripheral artery disease. High-fat milk was positively associated with CHD (RR 1.08 (95% confidence interval 1.00-1.16) per 200 g higher intake/day) and cheese was inversely associated with CHD (RR 0.96 (95% confidence interval 0.93-0.98) per 20 g higher intake/day). Heterogeneity, however, was observed in high versus low meta-analyses. Milk was inversely associated with ischemic stroke in high versus low meta-analysis only. In conclusion, this systematic review indicates a positive association of high-fat milk and an inverse association of cheese with CHD risk. The findings should be interpreted in the context of the observed heterogeneity.

High vs. low-fat dairy and milk differently affects the risk of all-cause, CVD, and cancer death: A systematic review and dose-response meta-analysis of prospective cohort studies

Considerable controversy exists regarding the association between milk and dairy consumption and mortality risk. The present systematic review and meta-analysis of prospective studies was undertaken to examine the association of high vs. low-fat dairy and milk consumption with mortality. We searched PubMed/Medline, ISI Web of Science, and Scopus databases through February 2020 for prospective cohort studies that reported the association between milk and dairy consumption and mortality risk. High-fat milk consumption was significantly associated with a greater risk of all-cause (Pooled ES: 1.15; 95% CI: 1.09-1.20, I²=24.5%, p = 0.22), CVD (Pooled ES: 1.09; 95% CI: 1.02-1.16, I²=4.5%, p = 0.38) and cancer mortality (Pooled ES: 1.17; 95% CI: 1.08-1.28, I²=30.1%, p = 0.19). However, total dairy consumption was associated with a lower risk of CVD mortality (Pooled ES: 0.93; 95% CI: 0.88-0.98, I²=59.7%, p = 0.001). Dose-response analysis revealed a significant non-linear association of total dairy consumption with all-cause and CVD mortality. Moreover, high-fat milk consumption was significantly associated with risk of cancer mortality in linear and non-linear dose-response analysis. In conclusion, we found high-fat milk consumption was associated with a higher risk of all-cause, CVD, and cancer mortality. However, total dairy consumption was associated with a lower risk of CVD mortality.

Consumption of Dairy Products in Relation to Type 2 Diabetes Mellitus in Chinese People: The Henan Rural Cohort Study and an Updated Meta-Analysis

Recent studies on whether dairy consumption is associated with type 2 diabetes mellitus (T2DM) have yielded inconsistent results, so we explored the relationship between dairy consumption and T2DM through a large-sample, cross-sectional study and a meta-analysis. In the meta-analysis, summary relative risks (RRs) of 23 articles were compiled with a random effects model, and a restricted cubic spline regression model was used to explore whether there is a nonlinear relationship between dairy intake and T2DM risk. This cross-sectional study used baseline data from 38,735 participants of the Henan Rural Cohort study and the association between dairy consumption and T2DM was analyzed by a logistic regression model. The meta-analysis revealed a borderline negative significant association between total dairy intake and risk of T2DM, the RR and 95% confidence interval (CI) was 0.94; (0.89, 1.00), and the risk was lowest at 270 g daily dairy intake. In the cross-sectional study, there were 3654 T2DM patients and 68.3 percent of the respondents had no dairy intake. The average intake of dairy in the total population was 12 g per day. Fully adjusted analyses suggested positive associations, with an odds ratio (OR) comparing the highest with the zero intake of 1.34 (95% CI: 1.22, 1.48) for all participants, which was unaffected by sex. Dairy intake in rural areas of Henan province is low, and we found, in the context of overall low dairy intake, that a high intake was positively associated with T2DM, which is inconsistent with the meta-analysis results suggesting that dairy has marginal protective effects against T2DM.

Cow's Milk and Dairy Consumption: Is There Now Consensus for Cardiometabolic Health?

Cow's milk and dairy products derived from this complex food source have long been proposed as beneficial to human health, yet underlying clinical evidence of direct benefit continues to raise controversy. Limited evidence supports positive cardiometabolic effects of a number of dairy macro- and micronutrient components including whey protein and casein, unsaturated fats, milk fat globule membrane (MFGM) and polar phospholipids, vitamin D and calcium, in addition to non-bovine components including bacterial and yeast probiotics. More controversial remain lipid components trans fats, including trans vaccenic acid, trans palmitoleic acid, and conjugated cis trans linoleic acid (CLA), plus medium-chain and odd-chain dairy fats. New evidence is rapidly identifying multiple pathways by which these dairy nutrients may effect health. Processing, including fermentation and homogenization, may also have positive effects. Conversely, the high saturated fat content of dairy has long raised concern, aligned with international guidelines to minimize dietary intake of animal-origin saturated fatty acids (SFA) to achieve better cardiometabolic health. However, led in part by observational studies and meta-analyses showing dairy to have no or even an inverse association with cardiometabolic health, evidence from randomized controlled trials (RCTs) has been scrutinized over the last 5 years, and focus on low-fat dairy has been challenged. Recent evidence supports the hypothesis that adverse effects of SFAs on metabolic health may be ameliorated when these fats are consumed within a complex matrix such as milk, cheese or yogurt, and that dairy food categories may influence outcomes as much as total fat content. For example, yogurt and high-fat, high-SFA cheese have a negative association with risk of type 2 diabetes (T2D) in many, not all, published trials. However, large sample dairy RCTs of long duration with CVD or T2D incidence as primary endpoints are lacking. This is a clear research gap, with these clinical studies required if a causative link between dairy and improved cardiometabolic health is to be confirmed and in turn promoted through dietary guidelines. Current advisories from national guidance groups such as American Heart Association (AHA) and European Society of Cardiology (ESC) continue to promote consumption of low-fat dairy products, whilst liquid milk and yogurt remain part of nutrition guidelines from joint American Diabetes Association (ADA)/European Association for Study of Diabetes (EASD) reports, and as part of a "no-one-size-fits-all" answer to diet and T2D by the ADA in their most recent 2019 Consensus Report.

Prevalence of fermented foods in the Dutch adult diet and validation of a food frequency questionnaire for estimating their intake in the NQplus cohort

Background

Humans have a long history of consuming fermented foods. However, their prevalence in human diets remains largely undetermined, and there is a lack of validated dietary assessment tools assessing the intake of different fermented products. This study aimed to identify fermented foods consumed in The Netherlands and determine the relative validity of a food frequency questionnaire (FFQ) compared to multiple 24-h recalls for estimating their intake.

Methods

The validation population consisted of 809 participants (53.1 ± 11.9 years) from a Dutch observational cohort (NQplus) who completed a FFQ and multiple 24-h recalls. Fermented foods from the FFQ and recalls were identified and aggregated into conventional food groups. Percent difference in mean intakes, quintile cross-classification, Spearman’s correlations, and Bland-Altman analyses were used to evaluate the agreement between the two dietary assessment methods.

Results

Approximately 16–18% of foods consumed by this population were fermented, and a further 9–14% were dishes containing a fermented ingredient. Fermented foods with the highest consumption included coffee (~ 453 g/day;~ 0.5% of daily energy intake), yoghurts (~ 88 g/day;~ 2.2%), beer (~ 84 g/day;~ 1.7%), wholegrain bread (~ 81 g/day;~ 9.4%), wine (~ 65 g/day;~ 2.7%), and cheese (~ 32 g/day;~ 5.0%). Mean percent difference between the FFQ and recalls was small for fermented beverages (coffee), breads (brown, white, wholegrain, rye), and fermented dairy (cheeses) (0.3–2.8%), but large for buttermilk and quark (≥53%). All fermented food groups had > 50% of participants classified into the same or adjacent quintile of intake (58%-buttermilk to 89%-fermented beverages). Strong Spearman’s correlations (crude/energy-adjusted r_s ≥ 0.50) were obtained for fermented beverages (coffee, beer, wine), cereals/grains (wholegrain bread), and dairy (yoghurts). For ‘other bread’, quark, and buttermilk, correlations were low (r_s < 0.20). Bland-Altman analyses revealed good agreement for fermented beverages (coffee, beer), breads (brown, wholegrain, rye, other), pastries, chocolate, and fermented dairy (cheeses) (mean difference: 0.1–9.3).

Conclusions

Fermented food groups with acceptable or good validity across all measures included commonly consumed foods in The Netherlands: fermented beverages (coffee), wholegrain and rye bread, and fermented dairy (cheeses). However, for less frequently consumed foods, such as quark and buttermilk, the levels of agreement were poor and estimates of intake should be interpreted with caution. This report provides the basis for developing a FFQ specific for fermented foods.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40795-020-00394-z.

Changes in Retinol Binding Protein 4 Level in Undernourished Children After a Nutrition Intervention Are Positively Associated With Mother's Weight but Negatively With Mother's Height, Intake of Whole Milk, and Markers of Systemic Inflammation: Results From a Community-Based Intervention Study

Background:

The changes of plasma retinol binding protein 4 (RBP4) level after a nutrition intervention can indicate the metabolic changes associated with the delivered intervention.

Objective:

We investigated the changes in plasma RBP4 level among 12- to 18-month-old children after a nutrition intervention and measured its association with subcutaneous adiposity, maternal characteristics, and inflammation.

Methods:

Data of 520 undernourished children (250 of them had length-for-age Z score [LAZ] <−1 to −2 and 270 had LAZ score <−2) were collected from the Bangladesh Environmental Enteric Dysfunction study conducted in Dhaka, Bangladesh. Multivariable linear regression and generalized estimation equations (GEE) modeling techniques were used to measure the association.

Results:

At baseline, median RBP4 level was 19.9 mg/L (interquartile range [IQR]: 7.96), and at the end of the intervention, it was 20.6 mg/L (IQR: 9.06). Percentage changes in plasma RBP4 level were not significantly associated (P > .05) with the percentage changes in child’s height, weight, and subcutaneous adiposity. But maternal height (regression coefficient, β = −1.62, P = .002) and milk intake (β = −0.05, P = .01) were negatively and maternal weight was positively associated (β = 0.56, P = .03) with the changes in RBP4 levels. The GEE models revealed negative association of RBP4 levels with C-reactive protein (CRP; β = −0.14, P < .05) and α-1-acid glycoprotein (AGP; β = −0.03, P < .05).

Conclusion:

Children whose mothers were taller experienced less increase in plasma RBP4 level, and children whose mothers had a higher weight experienced more increase in the RBP4 level from baseline. We have also found that CRP and AGP levels and intake of whole milk were negatively associated with the plasma RBP4 level.

The effects of dairy and dairy derivatives on the gut microbiota: a systematic literature review

The effects of dairy and dairy-derived products on the human gut microbiota remains understudied. A systematic literature search was conducted using Medline, CINAHL, Embase, Scopus, and PubMed databases with the aim of collating evidence on the intakes of all types of dairy and their effects on the gut microbiota in adults. Risk of bias was assessed using the Cochrane risk-of-bias tool.The search resulted in 6,592 studies, of which eight randomized controlled trials (RCTs) met pre-determined eligibility criteria for inclusion, consisting of a total of 468 participants. Seven studies assessed the effect of type of dairy (milk, yogurt, and kefir) and dairy derivatives (whey and casein) on the gut microbiota, and one study assessed the effect of the quantity of dairy (high dairy vs low dairy). Three studies showed that dairy types consumed (milk, yogurt, and kefir) increased the abundance of beneficial genera Lactobacillus and Bifidobacterium. One study showed that yogurt reduced the abundance of Bacteroides fragilis, a pathogenic strain. Whey and casein isolates and the quantity of dairy consumed did not prompt changes to the gut microbiota composition. All but one study reported no changes to bacterial diversity in response to dairy interventions and one study reported reduction in bacterial diversity in response to milk intake.In conclusion, the results of this review suggest that dairy products such as milk, yogurt, and kefir may modulate the gut microbiota composition in favor to the host. However, the broader health implications of these findings remain unclear and warrant further studies.

Modeling the Impact of Fat Flexibility With Dairy Food Servings in the 2015-2020 Dietary Guidelines for Americans Healthy U.S.-Style Eating Pattern

Background: The 2015-2020 Dietary Guidelines for Americans (DGA) recommends consuming low-fat or fat-free dairy foods due to concerns about energy and saturated fat intake. It also recommends consuming no more than 10% of daily calories from saturated fat. Objective: The objective was to assess the impact of replacing one serving of fat-free dairy foods in the Healthy U.S.-Style Eating Pattern (HUSEP) from the DGA with one serving of whole- or reduced-fat dairy foods. We hypothesized that this replacement would keep the HUSEP within calorie, saturated fat, and sodium limits. Methods: Utilizing the same modeling procedures as the 2015-2020 DGA, we assessed the nutrient composition of seven alternative models of the 2000-calorie HUSEP. These models replaced all three servings of dairy foods in the HUSEP with an updated fat-free dairy composite (Model 1) or one of three fat-free dairy servings in the HUSEP with: a whole-fat dairy food composite, a reduced-fat/low-fat dairy food composite, whole milk, reduced-fat milk, whole-fat cheese, or reduced-fat cheese (Models 2-7). Results: In all models, the amount of saturated fat did not exceed 10% of total calories, but the amount of energy increased by 45-94 calories. While still lower than current average intake (3,440 mg/d), sodium amounts in four of the seven models exceeded the 2,300 mg/d recommended intake level. Conclusions: Some reduced- and whole-fat dairy foods, especially milk, can fit into calorie-balanced healthy eating patterns that also align with saturated fat recommendations. Allowing some flexibility in fat level of dairy food servings aligns with the recommendations that calories from solid fats and added sugars are best used to increase the palatability of nutrient-dense foods.

The food-gut axis: lactic acid bacteria and their link to food, the gut microbiome and human health

Lactic acid bacteria (LAB) are present in foods, the environment and the animal gut, although fermented foods (FFs) are recognized as the primary niche of LAB activity. Several LAB strains have been studied for their health-promoting properties and are employed as probiotics. FFs are recognized for their potential beneficial effects, which we review in this article. They are also an important source of LAB, which are ingested daily upon FF consumption. In this review, we describe the diversity of LAB and their occurrence in food as well as the gut microbiome. We discuss the opportunities to study LAB diversity and functional properties by considering the availability of both genomic and metagenomic data in public repositories, as well as the different latest computational tools for data analysis. In addition, we discuss the role of LAB as potential probiotics by reporting the prevalence of key genomic features in public genomes and by surveying the outcomes of LAB use in clinical trials involving human subjects. Finally, we highlight the need for further studies aimed at improving our knowledge of the link between LAB-fermented foods and the human gut from the perspective of health promotion.

Fermented Dairy Products, Probiotic Supplementation, and Cardiometabolic Diseases: A Systematic Review and Meta-analysis

Fermented dairy foods (FDFs) and probiotics are promising tools for the prevention and management of cardiometabolic diseases (CMDs), respectively. The relation between the regular consumption of FDFs and CMD risk factors was assessed by prospective cohort studies (PCSs), and the effect of probiotic supplementation added into a dairy matrix on CMD parameters was evaluated by randomized controlled trials (RCTs). Moreover, the effects of probiotic supplementation added into a dairy matrix were compared with those administered in capsule/powder form. Twenty PCSs and 52 RCTs met the inclusion criteria for the systematic review and meta-analysis. In PCSs, fermented milk was associated with a 4% reduction in risk of stroke, ischemic heart disease, and cardiovascular mortality [RR (95% CI); 0.96 (0.94, 0.98)]; yogurt intake was associated with a risk reduction of 27% [RR (95% CI); 0.73 (0.70, 0.76)] for type 2 diabetes (T2D) and 20% [RR (95% CI); 0.80 (0.74, 0.87)] for metabolic syndrome development. In RCTs, probiotic supplementation added into dairy matrices produced a greater reduction in lipid biomarkers than when added into capsules/powder in hypercholesterolemic subjects, and probiotic supplementation by capsules/powder produced a greater reduction in T2D biomarkers than when added into dairy matrices in diabetic subjects. Both treatments (dairy matrix and capsules/powder) resulted in a significant reduction in anthropometric parameters in obese subjects. In summary, fermented milk consumption is associated with reduced cardiovascular risk, while yogurt intake is associated with a reduced risk of T2D and metabolic syndrome development in the general population. Furthermore, probiotic supplementation added into dairy matrices could be considered beneficial for lowering lipid concentrations and reducing anthropometric parameters. Additionally, probiotic capsule/powder supplementation could contribute to T2D management and reduce anthropometric parameters. However, these results should be interpreted with caution due to the heterogeneity of the studies and the different probiotic strains used in the studies. This trial is registered with PROSPERO (CRD42018091791) and the protocol can be accessed at http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42018091791.

Health Benefits of Lactic Acid Bacteria (LAB) Fermentates

Consuming fermented foods has been reported to result in improvements in a range of health parameters. These positive effects can be exerted by a combination of the live microorganisms that the fermented foods contain, as well as the bioactive components released into the foods as by-products of the fermentation process. In many instances, and particularly in dairy fermented foods, the microorganisms involved in the fermentation process belong to the lactic acid group of bacteria (LAB). An alternative approach to making some of the health benefits that have been attributed to fermented foods available is through the production of ‘fermentates’. The term ‘fermentate’ generally relates to a powdered preparation, derived from a fermented product and which can contain the fermenting microorganisms, components of these microorganisms, culture supernatants, fermented substrates, and a range of metabolites and bioactive components with potential health benefits. Here, we provide a brief overview of a selection of in vitro and in vivo studies and patents exclusively reporting the health benefits of LAB ‘fermentates’. Typically, in such studies, the potential health benefits have been attributed to the bioactive metabolites present in the crude fermentates and/or culture supernatants rather than the direct effects of the LAB strain(s) involved.

Yogurt consumption in relation to mortality from cardiovascular disease, cancer, and all causes: a prospective investigation in 2 cohorts of US women and men

BACKGROUND

Although a link between regular yogurt consumption and mortality appears plausible, data are sparse and have yielded inconsistent results.

OBJECTIVES

We examined the association between regular yogurt consumption and risk of all-cause and cause-specific mortality among US women and men.

METHODS

A total of 82,348 women in the Nurses' Health Study and 40,278 men in the Health Professionals Follow-Up Study without a history of cardiovascular disease (CVD) and cancer in 1980 (women) or 1986 (men) were followed up until 2012. Yogurt consumption was assessed by updated validated FFQs.

RESULTS

During 3,354,957 person-years of follow-up, 20,831 women and 12,397 men died. Compared with no yogurt consumption, the multivariable-adjusted HRs (95% CIs) of mortality were 0.89 (0.86, 0.93), 0.85 (0.81, 0.89), 0.88 (0.84, 0.91), and 0.91 (0.85, 0.98) for ≤1-3 servings/mo, 1 serving/wk, 2-4 servings/wk, and >4 servings/wk in women (P-trend = 0.34), respectively. For men, the corresponding HRs (95% CIs) were 0.99 (0.94, 1.03), 0.98 (0.91, 1.05), 1.04 (0.98, 1.10), and 1.05 (0.95, 1.16), respectively. We further noted inverse associations for cancer mortality (multivariable-adjusted HR comparing extreme categories: 0.87; 95% CI: 0.78, 0.98; P-trend = 0.04) and CVD mortality (HR: 0.92; 95% CI: 0.79, 1.08; P-trend = 0.41) in women, although the latter was attenuated in the multivariable-adjusted model. Replacement of 1 serving/d of yogurt with 1 serving/d of nuts (women and men) or whole grains (women) was associated with a lower risk of all-cause mortality, whereas replacement of yogurt with red meat, processed meat (women and men), and milk or other dairy foods (women) was associated with a greater mortality.

CONCLUSIONS

In our study, regular yogurt consumption was related to lower mortality risk among women. Given that no clear dose-response relation was apparent, this result must be interpreted with caution.

Yogurt Intake Reduces All-Cause and Cardiovascular Disease Mortality: A Meta-Analysis of Eight Prospective Cohort Studies

OBJECTIVE

To assess the relationship between yogurt intake and mortality risk from prospective cohort studies.

METHODS

The PubMed, EMBASE, and Web of Science databases were searched for all records related to yogurt intake and mortality risk [all-cause or cardiovascular disease (CVD) or cancer mortality] before October 1, 2018. The Newcastle-Ottawa Quality Scale was used to estimate the quality of all eligible articles. The results of the highest and lowest categories of yogurt intake in each study were collected and the effect size was pooled using a random effects model. The dose-response analysis was calculated using the generalized least squares trend estimation model.

RESULTS

Eight eligible cohort studies were included in this meta-analysis. There were 235,676 participants in the 8 studies, and the number of deaths was 14,831. Compared with the lowest category, the highest category of yogurt intake was not significantly related with all-cause mortality [hazard ratio (HR)=0.93; 95% confidence interval (CI): 0.85, 1.01], CVD mortality (HR=0.92; 95% CI: 0.81, 1.03) and cancer mortality (HR=0.97; 95% CI: 0.83, 1.12). These studies were homogenous, since the homogeneity test showed that I² was 28.7%, 15.1% and 11.8%, respectively. However, yogurt intake ⩾200 g/d was significantly associated with a lower all-cause mortality (HR=0.88; 95% CI: 0.80, 0.96) and CVD mortality (HR=0.87; 95% CI: 0.77, 0.99) in the subgroup analysis. The dose-response analysis showed that yogurt intake of 200 g/d was inversely associated with all-cause mortality (P=0.041, HR=0.95, 95% CI: 0.92, 1.00) and CVD mortality (P=0.009, HR=0.92, 95% CI: 0.86, 0.98), and all of which were linear relationship (P>0.05).

CONCLUSIONS

This review provided the evidence regarding yogurt intake can reduce all-cause and CVD mortality. Although some positive findings were identified, more high-quality cohort studies and randomized controlled trials are warranted on a possible protective effect of yoghurt on health.

Associations of dairy intake with risk of mortality in women and men: three prospective cohort studies

OBJECTIVE

To examine the association of consumption of dairy foods with risk of total and cause specific mortality in women and men.

DESIGN

Three prospective cohort studies with repeated measures of diet and lifestyle factors.

SETTING

Nurses' Health Study, Nurses' Health Study II, and the Health Professionals Follow-up Study, in the United States.

PARTICIPANTS

168 153 women and 49 602 men without cardiovascular disease or cancer at baseline.

MAIN OUTCOME MEASURE

Death confirmed by state vital records, the national death index, or reported by families and the postal system. During up to 32 years of follow-up, 51 438 deaths were documented, including 12 143 cardiovascular deaths and 15 120 cancer deaths. Multivariable analysis further adjusted for family history of cardiovascular disease and cancer, physical activity, overall dietary pattern (alternate healthy eating index 2010), total energy intake, smoking status, alcohol consumption, menopausal status (women only), and postmenopausal hormone use (women only).

RESULTS

Compared to the lowest category of total dairy consumption (average 0.8 servings/day), the multivariate pooled hazard ratio for total mortality was 0.98 (95% confidence interval 0.96 to 1.01) for the second category of dairy consumption (average 1.5 servings/day), 1.00 (0.97 to 1.03) for the third (average 2.0 servings/day), 1.02 (0.99 to 1.05) for the fourth (average 2.8 servings/day), and 1.07 (1.04 to 1.10) for highest category (average 4.2 servings/day; P for trend <0.001). For the highest compared to the lowest category of total dairy consumption, the hazard ratio was 1.02 (0.95 to 1.08) for cardiovascular mortality and 1.05 (0.99 to 1.11) for cancer mortality. For subtypes of dairy products, whole milk intake was significantly associated with higher risks of total mortality (hazard ratio per 0.5 additional serving/day 1.11, 1.09 to 1.14), cardiovascular mortality (1.09, 1.03 to 1.15), and cancer mortality (1.11, 1.06 to 1.17). In food substitution analyses, consumption of nuts, legumes, or whole grains instead of dairy foods was associated with a lower mortality, whereas consumption of red and processed meat instead of dairy foods was associated with higher mortality.

CONCLUSION

These data from large cohorts do not support an inverse association between high amount of total dairy consumption and risk of mortality. The health effects of dairy could depend on the comparison foods used to replace dairy. Slightly higher cancer mortality was non-significantly associated with dairy consumption, but warrants further investigation.

Dietary Protein Consumption and the Risk of Type 2 Diabetes: ADose-Response Meta-Analysis of Prospective Studies

The relationship between dietary protein consumption and the risk of type 2 diabetes (T2D) has been inconsistent. The aim of this meta-analysis was to explore the relations between dietary protein consumption and the risk of T2D. We conducted systematic retrieval of prospective studies in PubMed, Embase, and Web of Science. Summary relative risks were compiled with a fixed effects model or a random effects model, and a restricted cubic spline regression model and generalized least squares analysis were used to evaluate the diet–T2D incidence relationship. T2D risk increased with increasing consumption of total protein and animal protein, red meat, processed meat, milk, and eggs, respectively, while plant protein and yogurt had an inverse relationship. A non-linear association with the risk for T2D was found for the consumption of plant protein, processed meat, milk, yogurt, and soy. This meta-analysis suggests that substitution of plant protein and yogurt for animal protein, especially red meat and processed meat, can reduce the risk for T2D.

The Impact of Dairy Products in the Development of Type 2 Diabetes: Where Does the Evidence Stand in 2019?

The prevalence of type 2 diabetes (T2D) has increased rapidly. Adopting a heathy diet is suggested as one of the effective behaviors to prevent or delay onset of T2D. Dairy consumption has been recommended as part of a healthy diet, but there remains uncertainty in both the scientific community and the public about the effect of different dairy products on T2D risk. In a recent workshop, the evidence on dairy products and T2D risk was presented and discussed by a group of experts. The main conclusions from the workshop are presented in this position paper and are as follows. 1) Available evidence from large prospective cohort studies and limited randomized controlled trials (RCTs) suggests that total dairy consumption has a neutral or moderately beneficial effect on T2D risk. 2) Increasing evidence from prospective cohort studies indicates that yogurt is most strongly associated with a lower T2D risk, but evidence from RCTs is scarce. 3) Fatty acids from dairy (medium-chain, odd, and very long-chain SFAs as well as trans-palmitoleic acid) are associated with lower T2D risk and improved metabolic health, but more research is needed on studies that explore cause and effect relations to exclude the possibility that the dairy fatty acids simply serve as markers of overall dairy consumption. 4) The food matrix can be a stronger determinant of health effects than SFA content. This review further identifies research gaps in the existing knowledge and highlights key research questions that need to be addressed to better understand the impact of dairy consumption on future T2D risk.

Effects of Full-Fat and Fermented Dairy Products on Cardiometabolic Disease: Food Is More Than the Sum of Its Parts

Current dietary recommendations to limit consumption of saturated fat are largely based on early nutrition studies demonstrating a direct link between dietary saturated fat, elevated blood cholesterol levels, and increased risk of cardiovascular disease. As full-fat dairy products are rich in saturated fat, these dietary guidelines recommend consumption of fat-free or low-fat dairy products in place of full-fat dairy. However, dairy products vary greatly in both their nutrient content and their bioactive ingredients, and research increasingly highlights the importance of focusing on whole foods (i.e., the food matrix) as opposed to single nutrients, such as saturated fat. In fact, the weight of evidence from recent large and well-controlled studies, systematic reviews, and meta-analyses of both observational studies and randomized controlled trials indicates that full-fat dairy products, particularly yogurt and cheese, do not exert the detrimental effects on insulin sensitivity, blood lipid profile, and blood pressure as previously predicted on the basis of their sodium and saturated fat contents; they do not increase cardiometabolic disease risk and may in fact protect against cardiovascular disease and type 2 diabetes. Although more research is warranted to adjust for possible confounding factors and to better understand the mechanisms of action of dairy products on health outcomes, it becomes increasingly clear that the recommendation to restrict dietary saturated fat to reduce risk of cardiometabolic disease is getting outdated. Therefore, the suggestion to restrict or eliminate full-fat dairy from the diet may not be the optimal strategy for reducing cardiometabolic disease risk and should be re-evaluated in light of recent evidence.

Cow milk does not affect adiposity in growing piglets as a model for children

The effect of milk consumption on childhood obesity is unclear and a direct demonstration of an association is needed. In the present study, we used piglets as a model for prepubertal children to determine the effect of milk on adipose tissue. Two studies were conducted: study 1 with 5-wk-old male piglets (n = 8) and study 2 with 8- to 9-wk-old male piglets (n = 12). The piglets were fed a normal growing diet and randomly assigned to receive daily either 750 mL of whole cow milk or an isocaloric maltodextrin solution (control). For approximately 12 wk, body weight, feed intake, and subcutaneous back fat thickness were determined ultrasonographically and recorded. At euthanasia, back and neck fat thicknesses were measured and samples of back fat were collected for adipose histology. In study 1, but not study 2, piglets receiving milk grew more and ate more compared with control. In study 1, both back fat and neck fat thickness were greater in the milk-fed piglets and they had a higher frequency of small adipocytes and a lower frequency of intermediate and large adipocytes compared with controls. In study 2, control pigs had a significantly greater frequency of intermediate adipocytes but the milk-fed piglets tended to have a higher frequency of the largest adipocytes. In conclusion, milk has no apparent causal or consistent effect on adipose tissue in growing piglets.

Association between dairy intake and the risk of contracting type 2 diabetes and cardiovascular diseases: a systematic review and meta-analysis with subgroup analysis of men versus women

CONTEXT

The association between dairy product intake and the risk of developing type 2 diabetes (T2D) or cardiovascular disease (CVD) has been investigated in several studies, but little attention was given to the role of sex as a moderator of these associations. (In this article, the term "sex" is used to denote the biologically-based differences between males and females.).

OBJECTIVE

This meta-analysis examines whether dairy consumption has different effects on T2D and CVD in men and women.

DATA SOURCES

The PubMed database and previous reviews were searched for cohort studies published between 2006 and 2016.

DATA EXTRACTION AND ANALYSIS

Reported risk ratios (RRs) for T2D/CVD with high versus low dairy intake were extracted. A random-effects model has been used to calculate the pooled RR. A subgroup analysis was conducted to compare the results for men and women.

RESULTS

The present meta-analysis of 201 studies found that T2D (n = 16 studies) and CVD (n = 13 studies) are inversely associated with dairy intake. Subgroup analysis for sex showed that the association between dairy intake and T2D and between dairy intake and CVD are significant in women (RR for T2D = 0.868; 95%CI, 0.82-0.92; P < 0.001; RR for CVD = 0.837; 95%CI, 0.75-0.93; P < 0.001) but not in men.

CONCLUSIONS

There is an inverse association between high dairy intake and the risk of developing T2D and CVD in women.