Effects of regular-fat and low-fat dairy consumption on daytime ambulatory blood pressure and other cardiometabolic risk factors: a randomized controlled feeding trial

Dairy products and hypertension: Cross-sectional and prospective associations

BACKGROUND

The association between dairy intake and prevalence or incidence of hypertension remains controversial. We aimed to investigate the association between intake of different dairy products and prevalence and incidence of hypertension in a community-dwelling sample.

METHODS

Three cross-sectional studies (2009-12, 2014-17 and 2018-21) and one prospective study (2009-12 to 2018-21) were conducted in Lausanne, Switzerland. Dietary intake was assessed via a validated food frequency questionnaire. Dairy consumption was compared between participants with and without prevalent or incident hypertension.

RESULTS

For the cross-sectional analyses, data from 4437 (2009-12, 54.0% women, 57.7 ± 10.5 years), 2925 (2014-17, 53.4% women, 62.5 ± 10.0 years), and 2144 (2018-21; 53.3% women, 65.5 ± 9.6 years) participants were used. No consistent differences between participants with and without hypertension were found for all dairy products (total dairy, milk, yogurt, cheese, low-fat dairy, and full-fat dairy) although participants with hypertension tended to consume less cheese (51 ± 1 vs. 55 ± 1, p = 0.014, 52 ± 1 vs. 56 ± 1, p = 0.053, and 54 ± 1 vs. 56 ± 1 g/day for 2009-12, 2014-17 and 2018-21, respectively). For the prospective study, data from 2303 participants (60.8% women, 53.9 ± 9.0 years) were used. Irrespective of the dairy product considered, no association was found between quartiles of dairy consumption and development of hypertension. Similar findings were obtained after stratifying on dietary quality.

CONCLUSION

In this population-based study, no association was found between the consumption of different dairy products and the prevalence or incidence of hypertension.

Recommendations for Designing, Conducting, and Reporting Feeding Trials in Nutrition Research

Double-blind, placebo-controlled, randomized controlled trials are the gold standard for clinical trials in nutrition science. For trials of whole diets, dietary counseling is advantageous as they offer clinical translatability although can vary in the fidelity of the intended intervention from participant to participant and across studies. Feeding trials, in which most or all food is provided, offer high precision and can provide proof-of-concept evidence that a dietary intervention is efficacious and can also better evaluate the effect of known quantities of foods and nutrients on physiology. However, they come with additional methodological complexities. Feeding trials also call for a variety of unique methodological considerations, not least of which relate to the design and delivery of diets to participants. This review aims to provide a comprehensive summary of recommendations for design and conduct of feeding trials, encompassing domiciled and nondomiciled feeding trials. Several pertinent aspects of trial design and methodology are discussed, including defining the study population to maximize retention, safety, and generalizability of findings, recommendations for design of control interventions and optimizing blinding, and specific considerations for clinical populations. A detailed stepwise process for menu design, development, validation, and delivery are also presented. These recommendations aim to facilitate methodologic consistency and execution of high-quality feeding trials, ultimately facilitating improved understanding of the role of diet in treating disease and the underpinning mechanisms.

Contributions of Gamma-Aminobutyric Acid (GABA) Produced by Lactic Acid Bacteria on Food Quality and Human Health: Current Applications and Future Prospects

The need to increase food safety and improve human health has led to a worldwide increase in interest in gamma-aminobutyric acid (GABA), produced by lactic acid bacteria (LABs). GABA, produced from glutamic acid in a reaction catalyzed by glutamate decarboxylase (GAD), is a four-carbon, non-protein amino acid that is increasingly used in the food industry to improve the safety/quality of foods. In addition to the possible positive effects of GABA, called a postbiotic, on neuroprotection, improving sleep quality, alleviating depression and relieving pain, the various health benefits of GABA-enriched foods such as antidiabetic, antihypertension, and anti-inflammatory effects are also being investigated. For all these reasons, it is not surprising that efforts to identify LAB strains with a high GABA productivity and to increase GABA production from LABs through genetic engineering to increase GABA yield are accelerating. However, GABA's contributions to food safety/quality and human health have not yet been fully discussed in the literature. Therefore, this current review highlights the synthesis and food applications of GABA produced from LABs, discusses its health benefits such as, for example, alleviating drug withdrawal syndromes and regulating obesity and overeating. Still, other potential food and drug interactions (among others) remain unanswered questions to be elucidated in the future. Hence, this review paves the way toward further studies.

Full-fat dairy products and cardiometabolic health outcomes: Does the dairy-fat matrix matter?

Reducing dairy fat intake is a common dietary guideline to limit energy and saturated fatty acid intake for the promotion of cardiometabolic health. However, research utilizing a holistic, food-based approach to assess the consumption of the fat found in dairy, a broad and diverse food group, may provide new insight into these guidelines. Dairy fat is comprised of a diverse assembly of fatty acids, triacylglycerols, sterols, and phospholipids, all uniquely packaged in a milk fat globule. The physical structure of this milk fat globule and its membrane is modified through different processing methods, resulting in distinctive dairy-fat matrices across each dairy product. The objectives of this narrative review were to first define and compare the dairy-fat matrix in terms of its unique composition, physical structure, and fat content across common dairy products (cow's milk, yogurt, cheese, and butter). With this information, we examined observational studies and randomized controlled trials published within the last 10 years (2013-2023) to assess the individual effects of the dairy-fat matrix in milk, yogurt, cheese, and butter on cardiometabolic health and evaluate the implications for nutrition guidance. Searches conducted on Ovid MEDLINE and PubMed® utilizing search terms for cardiometabolic health, both broadly and regarding specific disease outcomes and risk factors, yielded 59 studies that were analyzed and included in this review. Importantly, this review stratifies by both dairy product and fat content. Though the results were heterogeneous, most studies reported no association between intake of these individual regular-fat dairy products and cardiometabolic outcome measures, thus, the current body of evidence suggests that regular-fat dairy product consumption may be incorporated within overall healthy eating patterns. Research suggests that there may be a beneficial effect of regular-fat milk and yogurt intake on outcome measures related to body weight and composition, and an effect of regular-fat cheese intake on outcome measures related to blood lipids, but more research is necessary to define the directionality of this relationship. Lastly, we identify methodological research gaps and propose future research directions to bolster the current evidence base available for ascertaining the role of dairy fat in a healthy diet.

Whole milk dairy foods and cardiometabolic health: dairy fat and beyond

Bovine dairy milk is a nutrient-rich matrix, but consumption of full-fat dairy food varieties has been claimed historically to be associated with poorer cardiometabolic health, a notion often attributed to the saturated fat content. However, continued investigation that includes observational studies and randomized controlled trials (RCTs) provide evidence that favorably supports full-fat dairy foods and their bioactive components on cardiometabolic health. This review addresses this controversy by examining the evidence surrounding full-fat dairy foods and their implications for human health. Dairy foods are heterogeneous, not just in their fat content but also in other compositional aspects within and between fermented (e.g., yogurt, cheese) and nonfermented products (e.g., milk) that could differentially influence cardiometabolic health. Drawing from complementary lines of evidence from epidemiological studies and RCTs, this review describes the health effects of dairy foods regarding their fat content, as well as their polar lipids that are concentrated in the milk fat globule fraction. Observational studies have limitedly supported the consumption of full-fat dairy to protect against cardiometabolic disorders. However, this framework has been disputed by RCTs indicating that dairy foods, regardless of their fat content or fermentation, are not detrimental to cardiometabolic health and may instead alleviate certain cardiometabolic risk factors. As dietary recommendations evolve, which currently indicate to avoid full-fat dairy foods, it is essential to consider the totality of evidence, especially from RCTs, while also recognizing that investigation is needed to evaluate the complexity of dairy foods within diverse dietary patterns and their impacts on cardiometabolic health.

Comparison of the impact of saturated fat from full-fat yogurt or low-fat yogurt and butter on cardiometabolic factors: a randomized cross-over trial

PURPOSE

Dairy foods are often a major contributor to dietary saturated fatty acids (SFA) intake. However, different SFA-rich foods may not have the same effects on cardiovascular risk factors. We compared full-fat yogurt with low-fat yogurt and butter for their effects on cardiometabolic risk factors in healthy individuals.

METHODS

Randomized, two-period crossover trial conducted from October 2022 to April 2023 among 30 healthy men and women (15 to receive full-fat yogurt first, and 15 to receive low-fat yogurt and butter first). Participants consumed a diet with 1.5-2 servings of full-fat (4%) yogurt or low-fat (< 1.5) yogurt and 10-15 g of butter per day for 4 weeks, with 4 weeks wash-out when they consumed 1.5-2 servings of low-fat milk. At baseline, and the end of each 4 weeks, fasting blood samples were drawn and plasma lipids, glycemic and inflammatory markers as well as expression of some genes in the blood buffy coats fraction were determined.

RESULTS

All 30 participants completed the two periods of the study. Apolipoprotein B was higher for the low-fat yogurt and butter [changes from baseline, + 10.06 (95%CI 4.64 to 15.47)] compared with the full-fat yogurt [-4.27 (95%CI, -11.78 to 3.23)] and the difference between two treatment periods was statistically significant (p = 0.004). Non-high-density lipoprotein increased for the low-fat yogurt and butter [change, + 5.06 (95%CI (-1.56 to 11.69) compared with the full-fat yogurt [change, - 4.90 (95%CI, -11.61 to 1.81), with no significant difference between two periods (p = 0.056). There were no between-period differences in other plasma lipid, insulin, and inflammatory biomarkers or leukocyte gene expression of ATP-binding cassette transporter 1 and CD36.

CONCLUSION

This study suggests that short-term intake of SFAs from full-fat yogurt compared to intake from butter and low-fat yogurt has fewer adverse effects on plasma lipid profile.

CLINICALTRIALS

GOV: NCT05589350, 10/15/2022.

Lack of change in blood pressure and arterial stiffness after high dairy intake in hyperinsulinemic subjects: a cross-over randomized controlled trial

To evaluate the effects of high dairy (HD) (≥4 servings/day), compared to adequate dairy (AD) (2-3 servings/day as per Canada's Food Guide for Healthy Eating (2007)), on blood pressure (BP) and measures of arterial stiffness in hyperinsulinemic subjects. In this cross-over clinical trial, hyperinsulinemic adults were randomized to AD and HD for 6 weeks. Anthropometric, glycemic, and lipid parameters were analyzed and dietary intake was evaluated; BP, carotid-femoral pulse wave velocity, augmentation index, and measures of arterial stiffness were assessed. Twenty-seven participants completed the study. Dairy intake was 2.2 ± 1.2 servings/day during AD. In addition, lower total and low-density lipoprotein (LDL) cholesterol were observed without significant change in BP or arterial stiffness between before and after AD. During HD, the subjects consumed 5.8 ± 1.9 servings/day of dairy products, providing a higher intake of protein, saturated fat, calcium, phosphorus, sodium, and potassium compared to the baseline diet. After the HD, subjects had higher body fat, fasting insulin, homeostatic model assessment for insulin resistance (HOMA-IR) index, and triglycerides without altering BP or arterial stiffness compared to before HD. Overall, adequate or high intake of total dairy did not modify BP or arterial stiffness in hyperinsulinemic adults after 6 weeks.

Dairy Foods: Beneficial Effects of Fermented Products on Cardiometabolic Health

PURPOSE OF REVIEW

This review of recent observational studies and understanding of the complex nature of dairy foods is intended to reappraise the effects of different types of dairy foods on cardiovascular disease (CVD).

RECENT FINDINGS

Recent guidelines from major cardiovascular societies suggest that apart from the adverse effect of butter, consumption of more complex dairy products notably fermented varieties and yogurt in particular, appear to be inversely associated with outcomes of CVD and type 2 diabetes (T2D). Reduced fat in dairy food remains preferred for people at increased CVD risk. Changed evidence has led to new advice regarding consumption of some dairy foods. The apparent beneficial effects of fermented milk products, particularly yogurt, allow for increased consumption of nutritious staple foods. Recent national guidelines reflect this view.

Association of milk consumption with all-cause mortality and cardiovascular outcomes: a UK Biobank based large population cohort study

BACKGROUND

The association of milk consumption with mortality and cardiovascular disease (CVD) outcomes was unclear.

OBJECTIVE

The present study was performed to reveal the association of full cream, semi-skimmed, skimmed, soy, and other milk with all-cause mortality and CVD outcomes.

METHODS

A prospective cohort study was performed using data from the UK Biobank. This study recruited 450,507 participants without CVD at baseline between 2006 and 2010 from UK Biobank and followed them up through 2021. Cox proportional hazard models were adopted to calculate the hazard ratios (HRs) and 95% confidence interval (CI) to understand the correlation between milk consumption and clinical outcomes. Subgroup and sensitivity analyses were further conducted.

RESULTS

Among the participants, 435,486 (96.7%) were milk consumers. Multivariable model indicated that the adjusted HR of association between milk consumption and all-cause mortality was 0.84 (95% CI 0.79 to 0.91; P = 0.000) for semi-skimmed milk; 0.82 (0.76 to 0.88; P = 0.000) for skimmed milk and 0.83 (0.75 to 0.93; P = 0.001) for soy milk. Semi-skimmed, skimmed, and soy milk use were significantly related to lower risks of CVD mortality, CVD event, and stroke.

CONCLUSION

Compared with non-milk users, semi-skimmed milk, skimmed milk, and soy milk consumption were related to a lower risk of all-cause mortality and CVD outcomes. Among them, skim milk consumption was more beneficial for all-cause mortality, while soy milk consumption was more beneficial for CVD outcomes.

Effect of High-Fat and Low-Fat Dairy Products on Cardiometabolic Risk Factors and Immune Function in a Low Birthweight Swine Model of Diet-Induced Insulin Resistance

Although dairy intake has been shown to have a neutral or some beneficial effect on major cardiometabolic risk factors, the impact of dairy, and especially dairy fat, on immune function remains to be investigated. To understand the effect of consuming dairy fat on cardiometabolic risk factors and immune function, we used an established low birthweight (LBW) swine model of diet-induced insulin resistance to compare high-fat and low-fat dairy products to a control high-fat diet (CHF). LBW piglets were randomized to consume one of the 3 experimental HF diets: (1) CHF, (2) CHF diet supplemented with 3 servings/day of high-fat dairy (HFDairy) and (3) CHF diet supplemented with 3 servings/day of low-fat dairy (LFDairy). As comparison groups, normal birthweight (NBW) piglets were fed a CHF (NBW-CHF) or standard pig grower diet (NBW-Chow). A total of 35 pigs completed the study and were fed for a total of 7 weeks, including 1 week of CHF transition diet. At 12 weeks of age, piglets were euthanized. Fasting blood and tissue samples were collected. Ex vivo cytokine production by peripheral blood mononuclear cells (PBMCs) stimulated with pokeweed (PWM), phytohemagglutinin (PHA) and phorbol myristate acetate-ionomycin (PMA-I) were assessed. As expected, LBW-CHF piglets showed early signs of insulin resistance (HOMA-IR, P model = 0.08). Feeding high-fat dairy products improved fasting plasma glucose concentrations more than low-fat dairy compared to LBW-CHF (P < 0.05). Irrespective of fat content, dairy consumption had neutral effect on fasting lipid profile. We have also observed lower production of IL-2 after PWM and PHA stimulation as well as lower production of TNF-α and IFN-γ after PWM stimulation in LBW-CHF than in NBW-Chow (all, P < 0.05), suggesting impaired T cell and antigen presenting cell function. While feeding high-fat dairy had minimal effect on immune function, feeding low-fat dairy significantly improved the production of IL-2, TNF-α and IFN-γ after PWM stimulation, IL-2 and IFN-γ after PHA stimulation as well as TNF-α after PMA-I stimulation compared to LBW-CHF (all, P < 0.05). These data provide novel insights into the role of dairy consumption in counteracting some obesity-related cardiometabolic and immune perturbations.

Effect of cow's milk with different PUFA n-6: n-3 ratios on performance, serum lipid profile, and blood parameters of grower gilts

The concern with human health has increased the interest in producing foods enriched with polyunsaturated fatty acids (PUFA), directly or naturally, by inclusion in the animals' diet. The positive effects such as antithrombotic, anti-inflammatory, and hypolipidemic have been observed in pigs and rats, used as human models for study. The present study evaluated the effect of cow's milk with different lipid profiles on performance, serum fatty acid profile, biochemical analysis, and a complete blood count of gilts used as a human model. At 34 days, thirty gilts were equally distributed in three treatments. Experimental treatments were milk from cows without the oil supplementation (C), milk from cows fed an enriched diet with linseed oil (n-3), and milk from cows fed an enriched diet with soybean oil (n-6). Milk supplementation was performed until 190 days old, provided once in the morning. The n-3 and n-6 milk reduced the concentration of myristic acid in the blood and increased the leukocytes. Milk enriched with n-3 compared to n-6 reduced the stearic acid. In conclusion, milk with a better PUFA profile can reduce saturated fatty acids in the blood and alter the concentration of cells in the defense system.

Influence of diet on acute endocannabinoidome mediator levels post exercise in active women, a crossover randomized study

The extended endocannabinoid system, also termed endocannabinoidome, participates in multiple metabolic functions in health and disease. Physical activity can both have an acute and chronic impact on endocannabinoid mediators, as does diet. In this crossover randomized controlled study, we investigated the influence of diet on the peripheral response to acute maximal aerobic exercise in a sample of active adult women (n = 7) with no underlying metabolic conditions. We compared the impact of 7-day standardized Mediterranean diet (MedDiet) and control diet inspired by Canadian macronutrient intake (CanDiet) on endocannabinoidome and short-chain fatty acid metabolites post maximal aerobic exercise. Overall, plasmatic endocannabinoids, their congeners and some polyunsaturated fatty acids increased significantly post maximal aerobic exercise upon cessation of exercise and recovered their initial values within 1 h after exercise. Most N-acylethanolamines and polyunsaturated fatty acids increased directly after exercise when the participants had consumed the MedDiet, but not when they had consumed the CanDiet. This impact was different for monoacylglycerol endocannabinoid congeners, which in most cases reacted similarly to acute exercise while on the MedDiet or the CanDiet. Fecal microbiota was only minimally affected by the diet in this cohort. This study demonstrates that endocannabinoidome mediators respond to acute maximal aerobic exercise in a way that is dependent on the diet consumed in the week prior to exercise.

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.

Decreased risk of all-cause and heart-specific mortality is associated with low-fat or skimmed milk consumption compared with whole milk intake: A cohort study

BACKGROUND&AIMS

It is controversial to preferentially choose low-fat milk or full-fat items. This study aimed to investigate the association of total and cause-specific mortality with 2 g/100 g or ≤ 1 g/100 g low-fat milk consumption compared with whole milk in general population.

METHODS

Overall, 29,283 adults aged ≥20 years from US National Health and Nutrition Examination Survey 1999-2014 were recruited with a median follow-up of 8.3 years. The types of milk consumption at baseline (e.g., whole-fat, 2 g/100 g low-fat, and ≤1 g/100 g low-fat) were reported during in-house interviews. Hazard ratios for the associations between milk types and mortality were assessed with the weighted Cox proportional regression.

RESULTS

During 241,572 person-years of follow-up, 4170 deaths occurred including 730 heart disease-related deaths and 846 cancer deaths. Consumption of milk contained lower fat exhibited an inverse association with total and cardiovascular mortality after multivariable adjustment. Compared with participants consuming whole-fat milk, those consuming 2 g/100 g or ≤1 g/100 g low-fat milk had a 14%-22% decrease in total mortality (p trend ≤0.001). Individuals consuming 2 g/100 g and ≤1 g/100 g low-fat milk had hazard ratios (95%CI) of 0.73 (0.55-0.97) and 0.67 (0.49-0.91) for heart-related mortality (p trend = 0.009). No significant difference was noted between whole-fat and lower-fat milk for mortality due to cancer, Alzheimer's disease, or diabetes mellitus. A similar trend was noted in the stratification and sensitivity analyses.

CONCLUSION

Compared with whole milk, low-fat or skim milk intake was associated with reduced total and heart-related mortality. Low-fat milk may be more conducive than whole milk for promoting cardiovascular health in general adults.

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.

Association between dairy product intake and high blood pressure in Chilean adults

BACKGROUND

Hypertension is a major risk for cardiovascular disease. Several studies have connected dairy consumption with lower blood pressure (BP). However, these have not considered the Latin American population. The aim of this study was to examine the relationship between consumption of full-fat or low fat/fat free dairy products and high blood pressure in Chilean adults.

METHODS

Cross-sectional study containing data from 3,807 adults between 20 and 98 years old from the National Health Survey (NHS) of Chile 2016-2017. Information on lifestyle, food frequency, and socio-demographics was collected using standardized questionnaires. Trained fieldworkers took anthropometric and blood pressure measurements. The frequency of consumption data included seven ad-hoc questions on habitual eating and frequency options, based on the Mediterranean diet (fish products, fruit and vegetable, and dairy products) and its protective effect on cardiovascular diseases. The selection of foods was supported by expert opinion.

RESULTS

Of the 3,807 adults, 37% were male and 63% were female. Sex, education level, frequency of dairy products and fish, smoking, and sport or physical activity had a direct relationship with consumption of dairy products (P < 0.05). Consumption of low fat/fat free dairy products was protectively associated with high blood pressure in the unadjusted model (OR: 0.76, CI 95% 0.64-0.91). However, after adjustment for confounding variables (education level modifies the effect 10.2%), this association was attenuated (OR: 0.88; CI 95% 0.71-1.08).

CONCLUSION

We found limited evidence that the type of dairy products consumed is associated with high blood pressure in the Chilean population.

Associations of dairy intake with risk of incident metabolic syndrome in children and adolescents: Tehran Lipid and Glucose Study

AIMS

This cohort study examined the association of total and individual dairy products with the risk of incident MetS and its components in children and adolescents.

METHODS

We prospectively assessed 531 participants aged 6-18 years without the MetS at baseline during an average 6.6-year follow-up period. Dairy consumption was estimated with a valid and reliable food frequency questionnaire. The MetS was defined according to the Cook criteria. The multivariable regression model was used to calculate the odds ratio (OR) for incident MetS associated with the consumption of dairy products.

RESULTS

The incidence of MetS was 9.8% after an average 6.6-year follow-up. After adjusting for potential confounders, OR (95% confidence interval) for incident MetS was 0.48 (0.23-1.00) for total dairy, 0.44 (0.21-0.92) for low-fat dairy, 0.46 (0.22-0.98) for low-fat milk, and 0.45 (0.21-0.97) for low-fat yogurt when comparing participants in the highest versus lowest tertile. A moderate intake of regular cheese was associated with decreased risk of MetS (OR = 0.43, 95% CI: 0.19-0.97). Replacing one serving/day of total dairy with nuts was associated with a lower (OR: 0.63, 95% CI: 0.42-0.95), whereas replacement by red and processed meat was associated with higher (OR: 1.55, 95%CI: 1.21-1.97) MetS risk. No significant association was found between high-fat dairy and MetS risk.

CONCLUSIONS

Higher consumption of dairy products, particularly low-fat milk and yogurt, was associated with reduced risk of incident MetS, suggesting the capability of low-fat dairy products in the primary prevention of MetS in children and adolescents.