Association of changes in red meat consumption with total and cause specific mortality among US women and men: two prospective cohort studies

Long-term BMI change trajectories in Chinese adults and its association with the hazard of type 2 diabetes: evidence from a 20-year China Health and Nutrition Survey

INTRODUCTION

To investigate the relationship between long-term change trajectory in body mass index (BMI) and the hazard of type 2 diabetes among Chinese adults.

RESEARCH DESIGN AND METHODS

Data were obtained from the China Health and Nutrition Survey (CHNS). Type 2 diabetes was reported by participants themselves in each survey wave. The duration of follow-up was defined as the period from the first visit to the first time self-reported type 2 diabetes, death, or other loss to follow-up from CHNS. The patterns of change trajectories in BMI were derived by latent class trajectory analysis method. The Fine and Gray regression model was used to estimate HRs with corresponding 95% CIs for type 2 diabetes.

RESULTS

Four patterns of the trajectories of change in BMI were identified among Chinese adults, 42.7% of participants had stable BMI change, 40.8% for moderate BMI gain, 8.9% for substantial BMI gain and 7.7% for weight loss. During the follow-up with mean 11.2 years (158 637 person-years contributed by 14 185 participants), 498 people with type 2 diabetes (3.7%) occurred. Risk of type 2 diabetes was increased by 47% among people who gained BMI more substantially and rapidly (HR: 1.47, 95% CI 1.08 to 2.02, p=0.016) and increased by 20% among those in people with the moderate BMI gain (HR: 1.20, 95% CI 0.98 to 1.48, p=0.078), compared with those with stable BMI change.

CONCLUSIONS

Long-term substantial gain of BMI was significantly associated with an increased risk of type 2 diabetes in the Chinese adults.

Differences in Consumer Preferences for Lamb Meat before and duriang the Economic Crisis in Spain. Analysis and Perspectives

Determining the preferences of food consumers is key for adapting supply and demand. This adaptation of supply is dynamic rather than static, given that it develops over time and is influenced by both social and economic factors. This work presents an analysis of the development of lamb meat consumption at two points in time, 2004 and 2014, before and in the midst of the economic crisis in Spain (2007–2017). Our findings show that together with the external appearance and against the backdrop of an economic recession, price has a greater impact on consumers’ purchasing decisions than origin and quality seals, despite these being attributes that are traditionally used as a guarantee of food safety and traceability. This suggests that in times of economic crisis consumer preferences shift towards attributes that are less related to product quality. Nonetheless, the comparison of the consumer segments for each of the years under study revealed that age and level of education are the socioeconomic factors that most influence the preferences of lamb meat consumers.

Vegetarian, pescatarian and flexitarian diets: sociodemographic determinants and association with cardiovascular risk factors in a Swiss urban population

Prevalence and trends of different vegetarian diets remain unknown, with estimates varying depending on the source. Evidence suggests that vegetarian diets are associated with a more favourable cardiovascular risk profile. The present study aimed to assess the prevalence and trends of different types of vegetarian diets in a population-based representative sample, sociodemographic characteristics of participants following such diets and the association of these diets with cardiovascular risk factors. Using repeated cross-sectional population-based surveys conducted in Geneva, Switzerland, 10 797 individuals participated in the study between 2005 and 2017. Participants were classified as vegetarians, pescatarians, flexitarians or omnivores using an FFQ. Sociodemographic and cardiovascular risk factors were evaluated through questionnaires, anthropometric measurements and blood tests. Findings show prevalence of vegetarians increased from 0·5 to 1·2 %, pescatarians from 0·3 to 1·1 % and flexitarians remained stable at 15·6 % of the population over the study period. Compared with omnivores, vegetarians were more likely to be young (OR 2·38; 95 % CI 1·01, 5·6), have higher education (OR 1·59; 95 % CI 1·01, 2·49) and lower income (OR 1·83; 95 % CI 1·04, 3·21); pescatarians and flexitarians were more likely to be women (pescatarian: OR 1·81; 95 % CI 1·10, 3·00; vegetarian: OR 1·57; 95 % CI 1·41, 1·75) and flexitarians were also more likely to have a lower income (OR 1·31; 95 % CI 1·13, 1·53). Participants who adhered to any diet excluding/reducing meat intake had lower BMI, total cholesterol and hypertension compared with omnivores. The present study shows an increase in the prevalence of vegetarians over a 13-year period and suggests that the different vegetarian diets assessed are associated with a better cardiovascular risk profile.

Dietary Intakes of Eggs and Cholesterol in Relation to All-Cause and Heart Disease Mortality: A Prospective Cohort Study

Background The aim of this study was to identify associations between dietary intakes of eggs and cholesterol and all-cause and heart disease mortality in a US population. Methods and Results Data from the National Health and Nutrition Examination Survey 1999-2014 were used in this study, which included 37 121 participants ≥20 years of age. Dietary information was assessed via 24-hour dietary recalls at baseline. Mortality status was documented until December 31, 2015. Cox proportional hazards models were used to examine the associations between dietary intakes of eggs and cholesterol and all-cause and heart disease mortality. During a median follow-up of 7.8 years, 4991 deaths were documented, including 870 deaths from heart disease. No significant association was observed between additional daily consumption of half an egg and all-cause mortality (multivariable-adjusted hazard ratio, 1.04; 95% CI, 0.96-1.13), or heart disease mortality (0.96; 0.80-1.14). Each 50-mg/day increase of cholesterol intake was inversely associated with all-cause mortality among participants with daily intake <250 mg (0.87; 0.77-0.98), but positively associated with all-cause mortality among participants with daily intake ≥250 mg (1.07; 1.01-1.12). No significant association was found between dietary cholesterol intake and heart disease mortality. Conclusions No significant association was found between egg consumption and mortality in US adults. The association between dietary cholesterol intake and all-cause mortality depended on the baseline intake levels, with an inverse association in those with lower intake levels (<250 mg/day) but a positive association in those with higher intake levels (≥250 mg/day).

Epidemiologic Burden of Red and Processed Meat Intake on Colorectal Cancer Mortality

A clear epidemiologic association has been reported between intake of red processed meat and colorectal cancer. Therefore, an electronic search was performed in Global Health Data Exchange (GHDx) registry, using the keywords "diet high in red meat", "diet high in processed meat", "colon and rectum cancer" and "death". According to this search, red and processed meat intake accounts for 1.77% and 1.18% worldwide colorectal cancer mortality, respectively. The death risk attributable to consumption of red meat linearly increased during the past decade (r = 0.99; p < 0.001), whilst that of processed meat exhibited linear decline (r= -0.97; p < 0.001). The risk of colorectal cancer death for both types of meat is higher in men than in women. Colorectal cancer mortality for red meat is mostly clustered in people <75 years, whilst that attributable to processed meat increases with ageing. A positive relationship can be observed between consumption of both meats and socio-demographic index (SDI). The risk of colorectal cancer deaths attributable to red meat is independently associated with male sex, higher SDI and younger age, whilst that of processed meat is independently associated with higher SDI and older age. Reinforced efforts shall be prioritized for broadening recommendations on decreasing red and processed meat consumption.

Association of Low-Carbohydrate and Low-Fat Diets With Mortality Among US Adults

IMPORTANCE

It is crucial to incorporate quality and types of carbohydrate and fat when investigating the associations of low-fat and low-carbohydrate diets with mortality.

OBJECTIVE

To investigate the associations of low-carbohydrate and low-fat diets with total and cause-specific mortality among US adults.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study used data from the US National Health and Nutrition Examination Survey from 1999 to 2014 from 37 233 adults 20 years or older with 24-hour dietary recall data. Data were analyzed from July 5 to August 27, 2019.

EXPOSURES

Overall, unhealthy, and healthy low-carbohydrate-diet and low-fat-diet scores based on the percentage of energy as total and subtypes of carbohydrate, fat, and protein.

MAIN OUTCOMES AND MEASURES

All-cause mortality from baseline until December 31, 2015, linked to National Death Index mortality data.

RESULTS

A total of 37 233 US adults (mean [SD] age, 49.7 [18.3] years; 19 598 [52.6%] female) were included in the present analysis. During 297 768 person-years of follow-up, 4866 total deaths occurred. Overall low-carbohydrate-diet and low-fat-diet scores were not associated with total mortality. The multivariable-adjusted hazard ratios for total mortality per 20-percentile increase in dietary scores were 1.07 (95% CI, 1.02-1.11; P = .01 for trend) for unhealthy low-carbohydrate-diet score, 0.91 (95% CI, 0.87-0.95; P < .001 for trend) for healthy low-carbohydrate-diet score, 1.06 (95% CI, 1.01-1.12; P = .04 for trend) for unhealthy low-fat-diet score, and 0.89 (95% CI, 0.85-0.93; P < .001 for trend) for healthy low-fat-diet score. The associations remained similar in the stratification and sensitivity analyses.

CONCLUSIONS AND RELEVANCE

In this study, overall low-carbohydrate-diet and low-fat-diet scores were not associated with total mortality. Unhealthy low-carbohydrate-diet and low-fat-diet scores were associated with higher total mortality, whereas healthy low-carbohydrate-diet and low-fat-diet scores were associated with lower total mortality. These findings suggest that the associations of low-carbohydrate and low-fat diets with mortality may depend on the quality and food sources of macronutrients.

Dietary Research on Coffee: Improving Adjustment for Confounding

Meta-analyses have reported higher levels of coffee consumption to be associated with lower mortality. In contrast, some systematic reviews have linked coffee consumption to increased risks for lung cancer and hypertension. Given these inconsistencies, this narrative review critically evaluated the methods and analyses of cohort studies investigating coffee and mortality. A specific focus was adjustment for confounding related to smoking, healthy and unhealthy foods, and alcohol. Assessment of 36 cohort samples showed that many did not adequately adjust for smoking. Consuming 1-5 cups of coffee per day was related to lower mortality among never smokers, in studies that adjusted for pack-years of smoking, and in studies adjusting for healthy and unhealthy foods. Possible reduced health benefits for coffee with added sugar have not been adequately investigated. Research on coffee and health should report separate analyses for never smokers, adjust for consumption of healthy and unhealthy foods, and for sugar added to coffee.

Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality

BACKGROUND

Plant-based diets have been associated with lower risk of type 2 diabetes mellitus and cardiovascular disease (CVD) and are recommended for both health and environmental benefits. However, the association between changes in plant-based diet quality and mortality remains unclear.

METHODS

We investigated the associations between 12-year changes (from 1986 to 1998) in plant-based diet quality assessed by 3 plant-based diet indices (score range, 18-90)-an overall plant-based diet index (PDI), a healthful PDI, and an unhealthful PDI-and subsequent total and cause-specific mortality (1998-2014). Participants were 49 407 women in the Nurses' Health Study (NHS) and 25 907 men in the Health Professionals Follow-Up Study (HPFS) who were free from CVD and cancer in 1998. Multivariable-adjusted Cox proportional-hazards models were used to estimate hazard ratios (HRs) and 95% CIs.

RESULTS

We documented 10 686 deaths including 2046 CVD deaths and 3091 cancer deaths in the NHS over 725 316 person-years of follow-up and 6490 deaths including 1872 CVD deaths and 1772 cancer deaths in the HPFS over 371 322 person-years of follow-up. Compared with participants whose indices remained stable, among those with the greatest increases in diet scores (highest quintile), the pooled multivariable-adjusted HRs for total mortality were 0.95 (95% CI, 0.90-1.00) for PDI, 0.90 (95% CI, 0.85-0.95) for healthful PDI, and 1.12 (95% CI, 1.07-1.18) for unhealthful PDI. Among participants with the greatest decrease (lowest quintile), the multivariable-adjusted HRs were 1.09 (95% CI, 1.04-1.15) for PDI, 1.10 (95% CI, 1.05-1.15) for healthful PDI, and 0.93 (95% CI, 0.88-0.98) for unhealthful PDI. For CVD mortality, the risk associated with a 10-point increase in each PDI was 7% lower (95% CI, 1-12%) for PDI, 9% lower (95% CI, 4-14%) for healthful PDI, and 8% higher (95% CI, 2-14%) for unhealthful PDI. There were no consistent associations between changes in plant-based diet indices and cancer mortality.

CONCLUSIONS

Improving plant-based diet quality over a 12-year period was associated with a lower risk of total and CVD mortality, whereas increased consumption of an unhealthful plant-based diet was associated with a higher risk of total and CVD mortality.