Dose-response meta-analysis of ultra-processed food with the risk of cardiovascular events and all-cause mortality: evidence from prospective cohort studies

Change in glucose, insulin and serum lipids due to ultra-processed food consumption in children with obesity

While the association between ultra-processed food (UPF) consumption and chronic non-communicable diseases in adults is well-established, its relationship with serum markers of chronic diseases in children remains underexplored. This research investigates changes in serum markers in children with obesity during a trial aimed at reducing UPF consumption. The study is a prospective cohort, based on a parallel randomized controlled trial conducted between August 2018 and February 2020, with children aged 7-12 years. Over 6 months, children and their guardians attended monthly consultations and educational activities aimed at reducing UPF consumption. Body weight, height, and 24-h dietary recall were measured at all visits. Serum markers were collected at baseline and at the 2- and 5-month visit (during the intervention). Data from 95 children were analysed. Body mass index (BMI), UPF consumption in grams and energy, and percentage of UPF in grams showed a quadratic trend, initially decreasing, followed by an increase in the following months. Glucose, insulin, and HOMA-IR decreased throughout the study, but after adjustment for BMI, the associations no longer persisted, except for glucose levels, which decreased linearly by 2.25 mg/dL. Reducing UPF consumption may lower blood glucose levels in children with obesity, independent of BMI changes.

Ultra-processed food intake, diet quality, and risk of gestational diabetes mellitus: a cross-sectional analysis from the Mutaba'ah study

BACKGROUND

High intake of Ultra-Processed Foods (UPF) has raised concerns about how they might impact maternal diet and potentially increase the risk of Gestational Diabetes Mellitus (GDM). This study aimed to evaluate the associations between UPF intake or adherence to the Mediterranean Diet and GDM among pregnant women in the United Arab Emirates.

METHODS

Pregnant women (n = 1054) from the dietary subcohort within the prospective Mutaba'ah Study cohort were included. Diet was assessed through a semi-quantitative food frequency questionnaire, and UPF intake in servings/day was classified according to the NOVA system. The alternate Mediterranean Diet (aMED) score specific for pregnancy defined adherence to the Mediterranean Diet. GDM diagnosis was based on the National Institute for Health and Clinical Excellence criteria. Logistic regression models adjusted for maternal age, first trimester body mass index, parity, gestational age, education level, employment status, physical activity, and husband's smoking status were used to assess associations between UPF intake or aMED score and GDM.

RESULTS

Mean ± SD UPF intake was 9.4 ± 3.4 servings/day and mean aMED score was 4.0 ± 1.5. Women in the highest tertile of UPF intake had lower aMED score than those in the lowest tertile (4.3 ± 1.4 vs. 3.6 ± 1.4, P < 0.001). Women in the highest tertile of UPF intake had higher intakes of carbohydrates, saturated fatty acids, sodium, and selenium than those in the lowest tertile, while intakes of protein, total fat, monounsaturated fatty acids, and most micronutrients were lower (P < 0.05). Neither tertiles of UPF intake (third tertile compared to the lowest OR = 0.85, 95% CI: 0.54-1.34) nor continuous UPF intake (OR = 0.97, 95% CI: 0.92-1.03) was associated with GDM. Similarly, aMED score was not associated with GDM in either tertile of the score (third tertile compared to the lowest OR = 0.94, 95% CI: 0.54-1.64) or as a continuous variable (OR = 0.99, 95% CI: 0.87-1.11).

CONCLUSIONS

Higher intake of UPF was associated with a lower adherence to the Mediterranean Diet. However, neither UPF intake nor aMED score was associated with GDM.

Ten-year trajectories of ultra-processed food intake and prospective associations with cardiovascular diseases and all-cause mortality: findings from the Whitehall II cohort study

BACKGROUND

Ultra-processed food (UPF) intake has been associated with adverse health outcomes; however, research on UPF intake and cardiovascular disease (CVD) prognosis has largely neglected its longitudinal pattern over time. This study investigated trajectories of UPF intake over a decade and their prospective associations with the risk of fatal and non-fatal CVD, as well as all-cause mortality, using data spanning from 16 to 19 years.

METHODS

This study utilized data from the British Whitehall II cohort study, including 7,138 participants (68.3% male; median baseline age 60.4 years), all free of CVD at baseline. Dietary intake was assessed using a validated 127-item food frequency questionnaire at three time points: phase 3 (1991-1994), phase 5 (1997-1999), and phase 7 (2002-2004). UPF intake was estimated using the Nova classification, and group-based trajectory modelling identified different longitudinal consumption patterns. Phase 7 (2002-2004) was the baseline for subsequent monitoring of cardiovascular events and mortality outcomes until 2019/2021. Multivariate Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs), adjusting for socio-demographics, lifestyle, diet quality, energy intake, and clinical factors.

RESULTS

Three distinct UPF trajectory groups were identified: high (26.2% of participants), moderate (52.9%) and low UPF intake (20.9%). All groups showed a slight increase in UPF intake over time. Over the median follow-up of 16 years for incident cases and 19 years for mortality, we observed 1,128 incident CVD events, 859 CHD cases and 1,314 deaths. The highest vs. lowest UPF intake group had a 23% higher risk of CVD (HR 1.23, 95% CI 1.01 to 1.40), and a 32% higher risk of CHD (HR 1.32, 95% CI 1.06 to 1.65). No significant associations were observed between UPF trajectory groups and CVD mortality, CHD mortality, or all-cause mortality.

CONCLUSIONS

Sustained high UPF intake over 10 years was associated with increased risks of non-fatal CVD and CHD but not with CVD-specific, CHD-specific, or all-cause mortality. These findings suggest that sustained high intake of UPF may be a modifiable risk factor for preventing non-fatal cardiovascular risks.

Lunch patterns of Brazilian adults and their association with socioeconomic and demographic characteristics: the 2017-2018 Brazilian National Dietary Survey

Lunch is an important meal in Brazil, with varying standards among different population groups. This study aims to determine the lunch dietary patterns of Brazilian adults and verify their association with socioeconomic and demographic characteristics. Data from the Brazilian National Dietary Survey were used, comprising 28,901 adults aged 19 to 59 years (excluding pregnant and lactating women). Food consumption was assessed via 24-hour recalls at the interviewee's home. A total of 1,832 food items were recorded, 1,120 of which were mentioned at lunch. Socioeconomic and demographic variables were obtained through a structured questionnaire. Dietary patterns were derived by factor analysis, considering the complexity of the sample. The mean scores and 95% confidence intervals for each dietary pattern were estimated across all levels of socioeconomic and demographic variables. Considering the complexity of the sampling design, all analyses were performed using the statistical package SAS OnDemand for Academics. In total, 3.4% of Brazilian adults reported not having lunch. In total, three patterns explained 30.7% of lunch variability: traditional Brazilian; salads; and protein-based meal with desserts and beverages. Men, individuals with less schooling, those with lower income, and residents of the Central-West and Northeast regions adhered more to the traditional pattern. Fruits did not play an essential role in any pattern. Adherence to dietary patterns varied according to socioeconomic and demographic factors.

Ultra-processed foods and risk of all-cause mortality: an updated systematic review and dose-response meta-analysis of prospective cohort studies

BACKGROUND

Ultra-processed food (UPF) consumption has been steadily increasing globally, yet the associated risk of all-cause mortality remains unclear. We aimed to assess the risk of all-cause mortality of UPFs via an updated systematic review and dose-response meta-analysis.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, and Cochrane Library for studies published until July 2, 2024, in addition to referred studies included in the previous systematic review. Prospective cohort studies assessing the association between NOVA classification-defined UPF consumption and all-cause mortality were included. Dose-response meta-analysis via a random-effect model was used to combine the results with hazard ratio (HR) as an effect measure.

RESULTS

Overall, 18 studies with 1,148,387 participants (173,107 deaths) were identified. Compared to the lowest, participants with the highest UPF consumption had a 15% increased risk of all-cause mortality (HR = 1.15, 95% CI 1.09-1.22; I2 = 83.0%). Furthermore, a 10% higher risk of all-cause mortality was detected with each 10% increment in UPF consumption (HR = 1.10, 95% CI 1.04-1.16; I2 = 91.0%). Dose-response analysis showed a positive linear association (Pdose-response < 0.001). Moreover, subgroups and sensitivity analyses indicated consistent findings, while meta-regression analyses suggested sex distributions partially explained heterogeneity, with a higher risk of all-cause mortality in males.

CONCLUSIONS

Our updated meta-analysis, incorporating a greater number of newly published cohort studies using NOVA classification with the largest sample size to date, strengthens the evidence linking higher UPF consumption to increased all-cause mortality risk. Strategies such as dietary guidelines and policies for limiting UPF consumption worldwide should be encouraged.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42023467226.

Associations between degree of food processing and all-cause and cause-specific mortality: a multicentre prospective cohort analysis in 9 European countries

Background

Ultra-processed food (UPF) consumption has been linked with higher risk of mortality. This multi-centre study investigated associations between food intake by degree of processing, using the Nova classification, and all-cause and cause-specific mortality.

Methods

This study analyzed data from the European Prospective Investigation into Cancer and Nutrition. All-cause mortality and cause-specific mortality due to cancer, circulatory diseases, digestive diseases, Parkinson's disease, and Alzheimer's disease served as endpoints. Hazard ratios (HRs) and 95% CIs were estimated using multivariable Cox proportional hazards regression models. Substitution analyses were also performed.

Findings

Overall, 428,728 (71.7% female) participants were included in the analysis and 40,016 deaths were documented after 15.9 years of follow-up. UPFs (in percentage grams per day [g/d]) were positively associated with all-cause mortality (HRs per 1-SD: 1.04; 95% CI: 1.02,1.05), as well as mortality from circulatory diseases (1.09; 95% CI: 1.07,1.12), cerebrovascular disease (1.11; 95% CI: 1.05,1.17), ischemic heart disease (1.10; 95% CI: 1.06,1.15), digestive diseases (1.12; 95% CI: 1.05,1.20), and Parkinson's disease (1.23; 95% CI: 1.06,1.42). No associations were found between UPFs and mortality from cancer or Alzheimer's disease. Replacing processed and UPFs with unprocessed/minimally processed foods was associated with lower mortality risk.

Interpretation

In this pan-European analysis, higher UPF consumption was associated with greater mortality from circulatory diseases, digestive diseases, and Parkinson's disease. The results support growing evidence that higher consumption of UPFs and lower consumption of unprocessed foods may have a negative impact on health.

Funding

l'Institut National du Cancer, and World Cancer Research Fund International.

Ultra-processed food consumption, plasma metabolite profile, and risk of all-cause and cause-specific mortality in a population-based cohort

BACKGROUND & AIMS

Epidemiological evidence on ultra-processed food (UPF) and cause-specific mortality remains limited and mixed. Molecular mechanisms underlying UPF intake and mortality remain unexplored. This study aimed to evaluate the associations between UPF consumption, metabolic signatures, and all-cause, premature, and cause-specific mortality.

METHODS

This study included 27670 participants (mean age 58.1 years) from the Malmö Diet and Cancer (MDC) cohort study. Consumption of UPF was assessed using a food frequency questionnaire and a 7-day food diary. In a subset of the MDC (n = 879), the associations of UPF with 991 plasma metabolites were investigated. An elastic net regression model was used to establish the metabolic signature of UPF. Cox proportional hazards regression model was used to determine the association between UPF intake, metabolic signature, and mortality risk.

RESULTS

During a median follow-up of 23.3 years, a total of 11333 participants died. UPF intake showed a nonlinear positive association with all-cause mortality, with more pronounced associations found in females (Pinteraction = 0.044); in females, UPF was linked to a higher mortality risk in a linear manner, while the association was J-shaped in males. Each standard deviation (SD) increment in UPF intake was associated with an increased risk of premature mortality (HR, 1.06; 95 % CI, 1.03-1.09), cardiovascular disease (CVD) mortality (HR, 1.05; 95 % CI, 1.01-1.08) or respiratory disease mortality (HR, 1.08; 95 % CI, 1.01-1.15), but not cancer mortality. The metabolic signature for UPF consumption (with 93 metabolites) was positively associated with all-cause mortality risk (HR per 1 SD, 1.23; 95 % CI, 1.06-1.42).

CONCLUSIONS

Our results suggest that higher UPF intake is associated with increased risk of all-cause, premature, CVD, and respiratory disease mortality, with the association varying across sex for all-cause mortality. The plasma metabolic signature of UPF showed a positive association with all-cause mortality.

Plant-based dietary patterns and ultra-processed food consumption: a cross-sectional analysis of the UK Biobank

Background

Dietary shift towards more plant-based options is increasingly popular, but the quantity of ultra-processed foods (UPFs) they contain is largely unknown. This study assessed the level of UPF and minimally processed food consumption among regular and low red meat eaters, flexitarians, pescatarians, vegetarians and vegans in a large dataset of United Kingdom (UK) adults.

Methods

This is a cross-sectional analysis of the UK Biobank participants recruited between December 19, 2006, and October 1, 2010. Responses to food frequency questions were used to identify diet types for vegans (never eating any animal-based foods); vegetarians (never eating meat/fish); pescatarians (never eating meat); flexitarians (consumed fish/meat under twice a week); low red meat eaters (consumed fish/poultry more than once a week but red/processed meat under twice a week); and regular red meat eaters (consumed red/processed meat more than once a week). Consumption of all food and drinks collected in 24-h recalls between April 29, 2009, and June 28, 2012, were categorised using the Nova classification. The primary outcomes are the consumption of UPFs and minimally processed foods, expressed as a percentage of daily food intake (grams/day). Multivariable linear regression assessed the mean percentage point difference in UPF and minimally processed food consumption between diet types.

Findings

This study included 199,502 UK Biobank participants (mean age 58.2 [standard deviation 7.9] years; 55.1% women). The mean UPF consumption was 24.2%, 21.9%, 22.0%, 20.4%, 23.8%, and 22.7% among 75,091 regular red meat eaters, 70,144 low red meat eaters, 45,057 flexitarians, 4932 pescatarians, 4119 vegetarians and 159 vegans, respectively. The adjusted results suggested that compared with regular red meat eaters, UPF consumption was 1.3 percentage points higher among vegetarians (95% confidence interval [CI]: 0.9, 1.7) and lower among low red meat eaters (-1.3, 95% CI: -1.4, -1.1), flexitarians (-0.8, 95% CI: -1.0, -0.7), and pescatarians (-1.6, 95% CI: -1.9, -1.2). The UPF consumption in vegans were not significantly different from regular red meat eaters (1.2 percentage points, 95% CI: -0.7, 3.2). Minimally processed food consumption was higher in all other types of diet than regular red meat eaters, with an adjusted percentage point difference ranged from 0.4 (95% CI: 0.005, 0.9) for vegetarians to 3.2 (95% CI: 1.0, 5.5) for vegans compared with regular red meat eaters.

Interpretation

This UK-based study found higher UPF consumption in vegetarian diets and lower in diets with a modest amount of meat or fish. It is important that policies which encourage the urgently needed transition to more sustainable dietary patterns also promote rebalancing diets towards minimally processed foods.

Funding

National Institute for Health and Care Research (NIHR) School for Public Health Research, World Cancer Research Fund.

Ultra-processed foods and the incidence of pre-diabetes and type 2 diabetes among Iranian adults: the Tehran lipid and glucose study

BACKGROUND

No study has investigated the association between ultra-processed food (UPF) and pre-diabetes development. Furthermore, prior investigations on the association between UPF and the risk of type 2 diabetes (T2D) were primarily conducted in Europe and America, and studies in other regions are lacking. We investigated the association between ultra-processed foods and the risk of pre-diabetes and T2D in a cohort of Iranians.

METHODS

This prospective study, with a sample size of 1954 for pre-diabetes and 2457 for T2D, was conducted among adults' participants (aged ≥ 18 years) from the Tehran Lipid and Glucose Study (TLGS). We defined UPF intake using NOVA calcification as a proportion of total energy, and calculated its average intake during the follow-ups. The hazard ratios (HR) and 95% confidence intervals (95% CI) for pre-diabetes/T2D across tertiles of total UPF and per 10% of its increment were examined using Cox proportional hazards models. We also investigated the possibility of non-linear association using a restricted cubic spline regression.

RESULTS

We identified 766 and 256 cases of pre-diabetes and T2D, respectively, during a median follow-up of 7 years for pre-diabetes and 8.6 years for T2D. In the multivariable adjusted model, a 10% increase in total UPF intake was associated with a 12% higher risk of pre-diabetes (HR = 1.12; 95% 1.02, 1.23). The incidence of pre-diabetes was also higher in those in tertile 3 than those in tertile 1 (HR = 1.28; 95% CI = 1.07, 1.52). Following additional adjustment for diet quality, the results remained unchanged. Spline regression demonstrated a J-shaped association between UPF and the risk of pre-diabetes; the risk of pre-diabetes did not increase until UPF consumption exceeded about 24% of total energy intake. Of the individual UPF, hydrogenated fat/mayonnaise/ margarine group was related to an increased risk of pre-diabetes. The total UPF and its individual items were not associated with T2D.

CONCLUSIONS

This study found a positive, non-linear relationship between total UPF and the risk of pre-diabetes in Iranian adults. Our data could not show any significant association between UPF and T2D risk.

Patterns of ultra-processed foods consumption throughout childhood and trajectories of growth and adiposity

BACKGROUND & AIMS

Ultra-processed foods (UPF) consumption has been associated with unhealthy outcomes. However, the literature lacks robust longitudinal studies considering its cumulative effect, particularly in young populations. This study aimed to evaluate the relationship between UPF consumption patterns throughout childhood with growth and adiposity trajectories.

METHODS

Generation XXI population-based birth cohort (Porto, Portugal) participants were included. Food frequency questionnaire items at 4, 7 and 10 years were classified according to the processing degree using NOVA. UPF consumption patterns based on total quantity were identified using a probabilistic Gaussian mixture model using participants with complete data and predicting for the total sample (n = 8647). To assess whether the outcome trajectories from 4 to 13 years [body weight (kg), height (cm), body mass index (BMI) z-score, waist circumference (WC) (cm) and fat mass (FM) (%)] depend on UPF patterns, a mixed-effects model with linear and quadratic terms for age adjusted for confounders was used. Participants with at least 2 measurements at 4, 7, 10 or 13 years were included in this study (n range: 5885-6272).

RESULTS

Four UPF consumption patterns were identified: constantly lower consumption (15.4%), constantly intermediate consumption (56.4%), transition from low to high consumption (11.2%), and constantly higher consumption (17.1%). Compared to the constantly lower UPF consumption, the constantly higher consumption pattern was associated with greater acceleration in body weight (β: 0.119; 95%CI: 0.027; 0.212), BMI z-score (β: 0.014; 95%CI: 0.004; 0.023), WC (β: 0.232; 95%CI: 0.144; 0.319) and FM% (β: 0.200; 95%CI: 0.092; 0.308) and with lower acceleration in height (β: -0.063; 95%CI: -0.111;-0.015). The constantly intermediate UPF consumption pattern was associated with greater acceleration in body weight (β: 0.123; 95%CI: 0.043; 0.203), WC (β: 0.120; 95%CI: 0.045; 0.195) and FM% (β: 0.146; 95%CI: 0.054; 0.238).

CONCLUSION

Constantly higher and constantly intermediate UPF consumption throughout childhood were associated with worse growth and adiposity trajectories until adolescence.

Ultra-processed foods and cardiovascular disease: analysis of three large US prospective cohorts and a systematic review and meta-analysis of prospective cohort studies

Background

Prospective associations between total and groups of ultra-processed foods (UPF) and cardiovascular disease (CVD) remained to be characterised. Our aim was to assess the association of total and group-specific UPF intakes with CVD, coronary heart disease (CHD), and stroke in three large prospective cohorts of US adults. Additionally, we conducted a systematic review and meta-analyses on the existing evidence on the associations of total UPF intake with these outcomes.

Methods

UPF intake was assessed through food frequency questionnaires in the Nurses' Health Study (NHS; n = 75,735), Nurses' Health Study II (NHSII; n = 90,813), and Health Professionals Follow-Up Study (HPFS; n = 40,409). Cox regression estimated cohort-specific associations of total and group-specific UPF intake with risk of CVD (cases = 16,800), CHD (cases = 10,401), and stroke (cases = 6758), subsequently pooled through fixed-effect models. Random-effects meta-analyses pooled existing prospective findings on the UPF-CVD association identified on Medline and Embase up to April 5, 2024, without language restrictions. Risk of bias was assessed with the Newcastle-Ottawa Scale, funnel plots, and Egger's tests, and meta-evidence was evaluated using NutriGrade.

Findings

The baseline mean (SD) age was 50.8 years (7.2) for the NHS, 36.7 years (4.6) for the NHSII, and 53.4 years (9.6) for the HPFS. The proportion of participants of White race was 97.7% in the NHS, 96.4% in the NHSII, and 94.9% in the HPFS. Among the three cohorts, multivariable-adjusted hazard ratios [HRs (95% CIs)] for CVD, CHD, and stroke for the highest (vs. lowest) total UPF intake quintile were 1.11 (1.06-1.16), 1.16 (1.09-1.24), and 1.04 (0.96-1.12), respectively. UPF groups demonstrated divergent associations. Sugar-/artificially-sweetened drinks and processed meats were associated with higher CVD risk, whereas inverse associations were observed for bread/cold cereals, yoghurt/dairy desserts, and savoury snacks. Meta-analysing 22 prospective studies showed that total UPF intake at the highest category (vs. lowest) was associated with 17% (11%-24%), 23% (12%-34%), and 9% (3%-15%) higher CVD, CHD, and stroke risk. Meta-evidence quality was high for CHD, moderate for CVD, and low for stroke.

Interpretation

Total UPF intake was adversely associated with CVD and CHD risk in US adults, corroborated by prospective studies from multiple countries, also suggesting a small excess stroke risk. Nutritional advice for cardiovascular health should consider differential consequences of group-specific UPF. Replication is needed in racially/ethnically-diverse populations.

Funding

National Institutes of Health (NIH) grants supported the NHS, NHSII, and HPFS.

The consumption of ultra-processed foods was associated with adiposity, but not with metabolic indicators in a prospective cohort study of Chilean preschool children

BACKGROUND

Increasing consumption of ultra-processed foods (UPF) has been identified as a risk factor for obesity and various diseases, primarily in adults. Nonetheless, research in children is limited, especially regarding longitudinal studies with metabolic outcomes. We aimed to evaluate the longitudinal association between consumption of UPF, adiposity, and metabolic indicators in Chilean preschool children.

METHODS

We conducted a prospective analysis of 962 children enrolled in the Food and Environment Chilean Cohort (FECHIC). Dietary data were collected in 2016 at age 4 years with 24-h recalls. All reported foods and beverages were classified according to the NOVA food classification, and the usual consumption of UPF in calories and grams was estimated using the Multiple Source Method. Adiposity (z-score of body mass index [BMI z-score], waist circumference [WC], and fat mass [in kg and percentage]) and metabolic indicators (fasting glucose, insulin, HOMA-IR, triglycerides, total cholesterol, and cholesterol fractions) were measured in 2018, at the age of 6 years. Linear regression models ((0) crude, (1) adjusted for covariables, and (2) adjusted for covariables plus total caloric intake) were used to evaluate the association between UPF and outcomes. All models included inverse probability weights to account for the loss to the follow-up.

RESULTS

At 4 years, usual consumption of UPF represented 48% of the total calories and 39% of the total food and beverages grams. In models adjusted for covariables plus caloric intake, we found a positive association between UPF and BMI z-score (for 100 kcal and 100 g, respectively: b = 0.24 [95%CI 0.16-0.33]; b = 0.21 [95%CI 0.10-0.31]), WC in cm (b = 0.89 [95%CI 0.41-1.37]; b = 0.86 [95%CI 0.32-1.40]), log-fat mass in kg b = 0.06 [95%CI 0.03-0.09]; b = 0.04 [95%CI 0.01-0.07]), and log-percentage fat mass (b = 0.03 [95%CI 0.01-0.04]; b = 0.02 [95%CI 0.003-0.04]), but no association with metabolic indicators.

CONCLUSIONS

In this sample of Chilean preschoolers, we observed that higher consumption of UPF was associated with adiposity indicators 2 years later, but not with metabolic outcomes. Longer follow-up might help clarify the natural history of UPF consumption and metabolic risks in children.

Toward a science-based classification of processed foods to support meaningful research and effective health policies

Processed foods have been part of the American diet for decades, with key roles in providing a safe, available, affordable, and nutritious food supply. The USDA Food Guides beginning in 1916 and the US Dietary Guidelines for Americans (DGA) since 1980 have included various types of commonly consumed processed foods (e.g., heated, fermented, dried) as part of their recommendations. However, there are multiple classification systems based on "level" of food processing, and additional evidence is needed to establish the specific properties of foods classified as "highly" or "ultra"-processed (HPF/UPFs). Importantly, many foods are captured under HPF/UPF definitions, ranging from ready-to-eat fortified whole grain breakfast cereals to sugar-sweetened beverages and baked goods. The consequences of implementing dietary guidance to limit all intake of foods currently classified as HPF/UPF may require additional scrutiny to evaluate the impact on consumers' ability to meet daily nutrient recommendations and to access affordable food, and ultimately, on health outcomes. Based on a meeting held by the Institute for the Advancement of Food and Nutrition Sciences in May 2023, this paper provides perspectives on the broad array of foods classified as HPF/UPFs based on processing and formulation, including contributions to nutrient intake and dietary patterns, food acceptability, and cost. Characteristics of foods classified as UPF/HPFs are considered, including the roles and safety approval of food additives and the effect of food processing on the food matrix. Finally, this paper identifies information gaps and research needs to better understand how the processing of food affects nutrition and health outcomes.

Ultra-processing should be understood as a holistic issue, from food matrix, to dietary patterns, food scoring, and food systems

The ultra-processed food (UPF) concept first emerged 15 years ago, and is now studied worldwide in different contexts, for example, human health, food behavior, socio-economic, food consumption, food scoring, and food system sustainability. Briefly, UPFs are defined as containing at least one marker of ultra-processing (MUP). MUPs are (1) cosmetic additives, (2) aromas, (3) some highly processed carbohydrates, proteins, fats, and/or fiber, and (4) drastic processes directly applied to food such as extrusion cooking or puffing. The first three categories of MUPs are on the food packaging in the list of ingredients, and are extracted, then purified, from raw foods or coming from artificial syntheses, leading to a-matrix/a-cellular compounds. Therefore, the core paradigm to define MUP is extreme food matrix degradation, and for UPF, matrix artificialization. Besides, UPFs are more than just junk food, encompassing numerous industrialized foods, falsely presented as healthy, for example, animal-based food analogs, but also organic, vegan, gluten-free, micronutrient-enriched, and/or light foods. In this way, UPFs are "high-quality junk foods." Otherwise, UPF being a holistic and indivisible concept by essence, we propose in this review to analyze ultra-processing at four holistic levels corresponding to four important scientific issues: the food matrix, the dietary pattern, food system, and food scoring. We reached the main conclusion that UPFs should be first studied with a holistic and scientifically based approach, not a reductionist one. Otherwise, we take the risk of performing greenwashing and create still more new health threats at a global level.

Animal vs Plant-Based Meat: A Hearty Debate

Plant-based meat alternatives (PBMAs) are highly processed food products that typically replace meat in the diet. In Canada, the growing demand for PBMAs coincides with public health recommendations to reduce ultra-processed food consumption, which prompts the need to investigate the long-term health implications of PBMAs. This review assesses the available literature on PBMAs and cardiovascular disease (CVD), including an evaluation of their nutritional profile and impact on CVD risk factors. Overall, the nutritional profiles of PBMAs vary considerably but generally align with recommendations for improving cardiovascular health; compared with meat, PBMAs are usually lower in saturated fat and higher in polyunsaturated fat and dietary fibre. Some dietary trials that have replaced meat with PBMAs have reported improvements in CVD risk factors, including total cholesterol, low-density lipoprotein cholesterol, apolipoprotein B-100, and body weight. No currently available evidence suggests that the concerning aspects of PMBAs (eg, food processing and high sodium content) negate the potential cardiovascular benefits. We conclude that replacing meat with PBMAs may be cardioprotective; however, long-term randomised controlled trials and prospective cohort studies that evaluate CVD events (eg, myocardial infarction, stroke) are essential to draw more definitive conclusions.

Ultra-processed food consumption and risk of chronic respiratory diseases mortality among adults: evidence from a prospective cohort study

PURPOSE

The purpose of the study was to determine the relationships between ultra-processed food (UPF) consumption and risk of mortality due to chronic respiratory diseases (CRDs) overall, chronic obstructive pulmonary disease (COPD), and lung cancer.

METHODS

A total of 96,607 participants aged 55 years and over were included from the Prostate, Lung, Colorectal and Ovarian (PLCO) cancer trial. Dietary intake was measured using food frequency questionnaire. Cox regression was fitted to estimate the risk of all-cause mortality and mortality due to CRDs overall, COPD and lung cancer associated with UPF intake. Competing risk regression was used to account for deaths from other causes and censoring.

RESULTS

During the follow-up of 1,379,655.5 person-years (median 16.8 years), 28,700 all-cause, 4092 CRDs, 2015 lung cancer and 1,536 COPD mortality occurred. A higher intake of UPF increased the risk of mortality from CRDs overall by 10% (HR 1.10; 95% CI 1.01, 1.22) and COPD by 26% (HR 1.26; 95% CI 1.06, 1.49) but not associated with lung cancer mortality risk (HR 0.97; 95% CI 0.84, 1.12). However, the risk of lung cancer increased by 16% (HR 1.16; 95% CI 1.01, 1.34) in the highest UPF intake after multiple imputation. Dose-response relationships existed for CRDs and COPD mortality but not lung cancer.

CONCLUSION

UPF consumption was associated with an increased risk of CRD mortality. The association between UPF consumption and lung cancer mortality is inconclusive and only significant when multiple imputation was applied.

Ultra-processed food consumption and cardiovascular events rate: An analysis from Isfahan Cohort Study (ICS)

BACKGROUND AND AIMS

The contribution of ultra-processed foods (UPFs) to daily energy intake and, therefore, their health effects may vary between countries. We aimed to investigate the association between UPFs and the incidence risk of cardiovascular events (CVEs) and cardiovascular mortality in the Isfahan cohort study.

METHODS AND RESULTS

In 2001, 6504 participants aged ≥35 years were enrolled and followed until 2017. Dietary intake was assessed using a validated food frequency questionnaire, and the NOVA system was applied for UPF classification. Any new case of CVE, including fatal and non-fatal myocardial infarction (MI) or stroke, unstable angina (UA), and CVD death, was recorded. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through Cox proportional hazards regression models. A total number of 819 CVE, 164 MI, 348 UA, 172 strokes, and 181 cardiovascular deaths were recorded during 61352.5 person-years of follow-up. The median (IQR) of UPF consumption was 2.47 (1.00-5.23) times/week. In the fully adjusted model, individuals in the fourth quartile of UPFs had no higher risk for incident MI and UA (HR = 1.12, 95% CI: 0.87, 1.46; P for trend = 0.364), stroke (HR = 0.93, 95% CI: 0.58, 1.46; P for trend = 0.601), cardiovascular mortality (HR = 0.95, 95% CI: 0.61, 1.47; P for trend = 0.596), and CVE (HR = 1.08, 95% CI: 0.88,1.34; P for trend = 0.515) in comparison with those in the first quartile.

CONCLUSION

This mid-term prospective cohort study provides no evidence for a significant association between UPF and CVE risk. Longer studies are required to confirm this association.

Ultra-processed foods and human health: An umbrella review and updated meta-analyses of observational evidence

BACKGROUND & AIMS

Ultra-processed food (UPF) intake has increased sharply over the last few decades and has been consistently asserted to be implicated in the development of non-communicable diseases. We aimed to evaluate and update the existing observational evidence for associations between ultra-processed food (UPF) consumption and human health.

METHODS

We searched Medline and Embase from inception to March 2023 to identify and update meta-analyses of observational studies examining the associations between UPF consumption, as defined by the NOVA classification, and a wide spectrum of health outcomes. For each health outcome, we estimated the summary effect size, 95% confidence interval (CI), between-study heterogeneity, evidence of small-study effects, and evidence of excess-significance bias. These metrics were used to evaluate evidence credibility of the identified associations.

RESULTS

This umbrella review identified 39 meta-analyses on the associations between UPF consumption and health outcomes. We updated all meta-analyses by including 122 individual articles on 49 unique health outcomes. The majority of the included studies divided UPF consumption into quartiles, with the lowest quartile being the reference group. We identified 25 health outcomes associated with UPF consumption. For observational studies, 2 health outcomes, including renal function decline (OR: 1.25; 95% CI: 1.18, 1.33) and wheezing in children and adolescents (OR: 1.42; 95% CI: 1.34, 1.49), showed convincing evidence (Class I); and five outcomes were reported with highly suggestive evidence (Class II), including diabetes mellitus, overweight, obesity, depression, and common mental disorders.

CONCLUSIONS

High UPF consumption is associated with an increased risk of a variety of chronic diseases and mental health disorders. At present, not a single study reported an association between UPF intake and a beneficial health outcome. These findings suggest that dietary patterns with low consumption of UPFs may render broad public health benefits.

Ultra-processed foods and incident cardiovascular disease and hypertension in middle-aged women

PURPOSE

Ultra-processed food (UPF) intake has increased in recent decades, yet limited knowledge of long-term effects on cardiovascular health persists and sex-specific data is scant. We determined the association of UPF intake with incident cardiovascular disease (CVD) and/or hypertension in a population-based cohort of women.

METHODS

In the Australian Longitudinal Study on Women's Health, women aged 50-55 years were prospectively followed (2001-2016). UPFs were identified using NOVA classification and contribution of these foods to total dietary intake by weight was estimated. Primary endpoint was incident CVD (self-reported heart disease/stroke). Secondary endpoints were self-reported hypertension, all-cause mortality, type 2 diabetes mellitus, and/or obesity. Logistic regression models assessed associations between UPF intake and incident CVD, adjusting for socio-demographic, medical comorbidities, and dietary variables.

RESULTS

We included 10,006 women (mean age 52.5 ± 1.5; mean UPF intake 26.6 ± 10.2% of total dietary intake), with 1038 (10.8%) incident CVD, 471 (4.7%) deaths, and 4204 (43.8%) hypertension cases over 15 years of follow-up. In multivariable-adjusted models, the highest [mean 42.0% total dietary intake] versus the lowest [mean 14.2% total dietary intake] quintile of UPF intake was associated with higher incident hypertension [odds ratio (OR) 1.39, 95% confidence interval (CI) 1.10-1.74; p = 0.005] with a linear trend (ptrend = 0.02), but not incident CVD [OR 1.22, 95% CI 0.92-1.61; p = 0.16] or all-cause mortality (OR 0.80, 95% CI 0.54-1.20; p = 0.28). Similar results were found after multiple imputations for missing values.

CONCLUSION

In women, higher UPF intake was associated with increased hypertension, but not incident CVD. These findings may support minimising UPFs within a healthy diet for women.

Ultra-processed food consumption and risk of cardiovascular events: a systematic review and dose-response meta-analysis

Background

Ultra-processed food (UPF) consumption continues to increase worldwide. However, evidences from meta-analyses are limited regarding the effects on cardiovascular events (CVEs).

Methods

A meta-analysis was performed to assess the dose-response relationship of UPF consumption and CVEs risk (including the morbidity and mortality of cardiovascular causes, and myocardial infarction, stroke, transient ischemic attack, coronary intervention). Databases (PubMed, EMBASE, Cochrane Library, and Web of Science) were searched for observational studies published in English language up to October 24, 2023. Generalized least squares regression and restricted cubic splines were used to estimate the linear/nonlinear relationship. PROSPERO CRD 42023391122.

Findings

Twenty studies with 1,101,073 participants and 58,201 CVEs cases with a median follow-up of 12.2 years were included. A positive linear relationship between UPF intake and CVEs risk was identified. In addition, positive correlation between coronary heart disease and UPF consumption in terms of daily serving and daily energy proportion. No significant association of UPF consumption with the risk of cerebrovascular disease was observed. Briefly, 10% increase of UPF by daily weight proportion was associated with a 1.9% increase of CVEs risk (RR = 1.019; 95% CI, 1.007-1.031; P = 0.002), an additional daily serving corresponding to 2.2% CVEs risk increase (RR = 1.022; 95% CI, 1.013-1.031; P < 0.001), and 10% increase by daily energy proportion corresponding to 1.6% CVEs risk increase (RR = 1.016; 95% CI, 1.002-1.030; P = 0.022).

Interpretation

UPF consumption were associated with a higher risk of CVEs in the positive linear relationship. Our findings highlight the importance of minimizing UPF consumption for cardiovascular health and might be help to pursue public health policies in control of UPF consumption.

Funding

This work was supported by the Key Research and Development Program of Shaanxi Province (2023-ZDLSF-22), the Innovative Talent Support Program of Shaanxi Province (2022KJXX-106), and the Key Research and Development Program of Shaanxi Province (2023-YBSF-424).

Reporting quality and risk of bias of systematic reviews of ultra-processed foods: a methodological study

A dramatic shift in the global food system is occurring with the rapid growth of ultra-processed foods (UPFs) consumption, which poses potentially serious health risks. Systematic review (SR) method has been used to summarise the association between UPF consumption and multiple health outcomes; however, a suboptimal-quality SR may mislead the decision-making in clinical practices and health policies. Therefore, a methodological review was conducted to identify the areas that can be improved regarding the risk of bias and reporting quality of relevant SRs. Systematic searches to collect SRs with meta-analyses of UPFs were performed using four databases from their inception to April 14, 2023. The risk of bias and reporting quality were evaluated using ROBIS and PRISMA 2020, respectively. The key characteristics of the included SRs were summarised descriptively. Excel 2019 and R 4.2.3 were used to analyse the data and draw graphs. Finally, 16 relevant SRs written in English and published between 2020 and 2023 in 12 academic journals were included. Only one SR was rated as low risk of bias, and the others were rated as higher risk of bias mainly because the risk of bias in the original studies was not explicitly addressed when synthesising the evidence. The reporting was required to be advanced significantly, involving amendments of registration and protocol, data and analytic code statement, and lists of excluded studies with justifications. The reviews' results could improve the quality, strengthen future relevant SRs' robustness, and further underpin the evidence base for supporting clinical decisions and health policies.

Ultra-processed food consumption and human health: an umbrella review of systematic reviews with meta-analyses

Recently, ultra-processed foods received a lot of attention, but also criticism. Our aim was to provide an overview of the existing evidence of ultra-processed food consumption on human health. We conducted a systematic search in four databases until January 5th, 2024. Systematic reviews with meta-analyses on ultra-processed food consumption as defined by the NOVA classification system were included. The certainty of evidence was evaluated by the GRADE approach. We identified 16 publications. Moderate certainty of evidence was found for all-cause mortality (Summary Risk Ratio per 50 g: 1.02; 95% confidence Interval (CI): 1.01, 1.03), cardiovascular disease incidence and mortality (per 50 g/d: 1.04; 95% CI: 1.02, 1.06, and 1.05; 95% CI: 1.01, 1.08), type 2 diabetes incidence (per 10%: 1.12; 95% CI: 1.10, 1.13) and colorectal cancer (per 10%: 1.04; 95% CI: 1.01, 1.07). For several outcomes such as inflammatory bowel diseases, obesity, metabolic syndrome, nonalcoholic fatty liver disease, mental health as well as nutrient quality, similar estimates were observed, but certainty of evidence was limited. Discussing the NOVA concept, it remains unclear whether the processing of foods leads to increased health risks or if ultra-processed food consumption is only a measure for poor diet quality.

Industrial Use of Phosphate Food Additives: A Mechanism Linking Ultra-Processed Food Intake to Cardiorenal Disease Risk?

The consumption of ultra-processed food (UPF) keeps rising, and at the same time, an increasing number of epidemiological studies are linking high rates of consumption of UPF with serious health outcomes, such as cardiovascular disease, in the general population. Many potential mechanisms, either in isolation or in combination, can explain the negative effects of UPF. In this review, we have addressed the potential role of inorganic phosphate additives, commonly added to a wide variety of foods, as factors contributing to the negative effects of UPF on cardiorenal disease. Inorganic phosphates are rapidly and efficiently absorbed, and elevated serum phosphate can lead to negative cardiorenal effects, either directly through tissue/vessel calcification or indirectly through the release of mineral-regulating hormones, parathyroid hormone, and fibroblast growth factor-23. An association between serum phosphate and cardiovascular and bone disease among patients with chronic kidney disease is well-accepted by nephrologists. Epidemiological studies have demonstrated an association between serum phosphate and dietary phosphate intake and mortality, even in the general American population. The magnitude of the role of inorganic phosphate additives in these associations remains to be determined, and the initial step should be to determine precise estimates of population exposure to inorganic phosphate additives in the food supply.