Associations of Calcium and Dairy Products with All-Cause and Cause-Specific Mortality in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Prospective Cohort Study

Associations between dairy intake and mortality due to all-cause and cardiovascular disease: the Japan Public Health Center-based prospective study

BACKGROUND

Some studies have investigated the relation between dairy products and mortality, but with inconsistent results.

OBJECTIVE

We examined the association between the consumption of dairy products and the risk of all-cause, cancer-related, and cardiovascular disease (CVD)-related mortality.

METHODS

From the Japan Public Health Center-based Prospective (JPHC) study, 43,117 males and 50,193 females with no history of cancer or CVD finished the food frequency questionnaire (FFQ) and were included in the study. Intake of dairy products was assessed using the FFQ and adjusted for total energy by using the residual method. We used multivariate Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for mortality risk in males and females.

RESULTS

14,211 deaths in males and 9547 deaths in females from all causes were identified during an average follow-up of 19.3 years. For males, total dairy consumption was nonlinearly and significantly associated with lower risk of mortality from all causes [the third quartile, HR = 0.87 (0.83, 0.91), the fourth quartile, HR = 0.89 (0.85, 0.94), P for nonlinearity < 0.001] and CVD [the third quartile, HR = 0.77 (0.70, 0.85), the fourth quartile, HR = 0.78 (0.70, 0.86), P for nonlinearity < 0.001]. Milk and fermented milk intake were inversely associated with all-cause and CVD-related mortality in males. Cheese consumption was inversely associated with CVD-related mortality among males. There was no association between total dairy intake and mortality risk among females.

CONCLUSION

For Japanese people, consumption of dairy products was associated with a decreased risk of mortality from all-cause and cardiovascular diseases among males.

Association between Dairy Product Intake and Risk of Fracture among Adults: A Cohort Study from China Health and Nutrition Survey

Background: The current literature reports inconsistent associations between dairy product intake and fracture. This study assessed the association between dairy product intake and the risk of fracture among Chinese adults and examined the mediation effects of height and body mass index (BMI) on the association. Methods: Data in 1997−2015 from the China Health and Nutrition Survey were used. Dietary data were collected by a 24-hour dietary recall, and occurrences of fracture were obtained by self-report of participants. Cumulative average intake of daily dairy products was calculated by the sum of the dairy product intake and divided by the total waves of participating in the surveys before fracture. Cox proportion hazard regressions were performed to explore the associations between dairy product intake and the risk of fracture. Mediation analysis models were established to examine the mediation effects of height and BMI on the associations. Results: A total of 14,711 participants were included. Dairy product intake of 0.1−100 g/day was associated with a decreased risk of fracture, while no association was observed among participants with dairy product intake of >100 g/day. The indirect effects of dairy product intake on the fracture mediated by height and BMI were much smaller than the direct effects. Conclusions: Dairy product intake with 0.1−100 g/day is associated with a lower risk of fracture, and the association is mainly a direct result of nutrients in dairy products and much less a result of the mediation effects of height or BMI. Dairy product intake of 0.1−100 g/day might be a cost-effective measure for Chinese adults to decrease fracture incidence.

Association between Milk Intake and All-Cause Mortality among Chinese Adults: A Prospective Study

BACKGROUND

Little is known about the effect of milk intake on all-cause mortality among Chinese adults. The present study aimed to explore the association between milk intake and all-cause mortality in the Chinese population.

METHODS

Data from 1997 to 2015 of the China Health and Nutrition Survey (CHNS) were used. A total of 14,738 participants enrolled in the study. Dietary data were obtained by three day 24-h dietary recall. All-cause mortality was assessed according to information reported. The association between milk intake and all-cause mortality were explored using Cox regression and further stratified with different levels of dietary diversity score (DDS) and energy intake.

RESULTS

11,975 (81.25%) did not consume milk, 1341 (9.10%) and 1422 (9.65%) consumed 0.1-2 portions/week and >2 portions/week, respectively. Milk consumption of 0.1-2 portions/week was related to the decreased all-cause mortality (HR: 0.59, 95% CI: 0.41-0.85). In stratified analysis, consuming 0.1-2 portions/week was associated with decreased all-cause mortality among people with high DDS and energy intake.

CONCLUSIONS

Milk intake is low among Chinese adults. Consuming 0.1-2 portions of milk/week might be associated with the reduced risk of death among Chinese adults by advocating health education. Further research is required to investigate the relationships between specific dairy products and cause-specific mortality.

Dairy Consumption and Total Cancer and Cancer-Specific Mortality: A Meta-Analysis of Prospective Cohort Studies

The association between dairy consumption and cancer mortality varies among studies and remains unclear. Thus, we conducted a comprehensive meta-analysis of prospective cohort studies to examine the association between dairy consumption and total cancer and cancer-specific mortality. We sought eligible studies in PubMed and Web of Science databases for all publications through March 2021, and pooled RRs and 95% CIs were calculated. We identified 34 prospective cohort studies including 3,171,186 participants and 88,545 deaths. Compared with low milk consumption, high milk consumption was associated with higher cancer mortality in females (RR: 1.10; 95% CI: 1.01, 1.21) and people consuming high/whole-fat milk (fat content ≥3.5%) (RR: 1.17; 95% CI: 1.07, 1.28). Increased risks of cancer-specific mortality were detected for liver (RR: 1.13; 95% CI: 1.02, 1.26), ovarian (RR: 1.32; 95% CI: 1.13, 1.55), and prostate (RR: 1.23; 95% CI: 1.02, 1.48) cancers. Also, females with high consumption of fermented milk had a lower cancer mortality risk (RR: 0.85; 95% CI: 0.77, 0.94). High cheese consumption was not associated with total cancer mortality but rather with higher colorectal cancer mortality (RR: 1.22; 95% CI: 1.02, 1.46). There was no association between butter (RR: 1.06; 95% CI: 0.70, 1.59) or total dairy product consumption (RR: 0.99; 95% CI: 0.95, 1.03) and cancer mortality. Our results imply that high milk consumption, especially high/whole-fat milk, was associated with higher cancer mortality, whereas fermented milk consumption was associated with lower cancer mortality, and this was particularly evident in females. Consequently, further studies are warranted.

Calcium intake, calcium supplementation and cardiovascular disease and mortality in the British population: EPIC-norfolk prospective cohort study and meta-analysis

The role of dietary calcium in cardiovascular disease prevention is unclear. We aimed to determine the association between calcium intake and incident cardiovascular disease and mortality. Data were extracted from the European Prospective Investigation of Cancer, Norfolk (EPIC-Norfolk). Multivariable Cox regressions analysed associations between calcium intake (dietary and supplemental) and cardiovascular disease (myocardial infarction, stroke, heart failure, aortic stenosis, peripheral vascular disease) and mortality (cardiovascular and all-cause). The results of this study were pooled with those from published prospective cohort studies in a meta-analsyis, stratifying by average calcium intake using a 700 mg/day threshold. A total of 17,968 participants aged 40-79 years were followed up for a median of 20.36 years (20.32-20.38). Compared to the first quintile of calcium intake (< 770 mg/day), intakes between 771 and 926 mg/day (second quintile) and 1074-1254 mg/day (fourth quintile) were associated with reduced all-cause mortality (HR 0.91 (0.83-0.99) and 0.85 (0.77-0.93), respectively) and cardiovascular mortality [HR 0.95 (0.87-1.04) and 0.93 (0.83-1.04)]. Compared to the first quintile of calcium intake, second, third, fourth, but not fifth quintiles were associated with fewer incident strokes: respective HR 0.84 (0.72-0.97), 0.83 (0.71-0.97), 0.78 (0.66-0.92) and 0.95 (0.78-1.15). The meta-analysis results suggest that high levels of calcium intake were associated with decreased all-cause mortality, but not cardiovascular mortality, regardless of average calcium intake. Calcium supplementation was associated with cardiovascular and all-cause mortality amongst women, but not men. Moderate dietary calcium intake may protect against cardiovascular and all-cause mortality and incident stroke. Calcium supplementation may reduce mortality in women.

Total, dietary, and supplemental calcium intake and risk of all-cause cardiovascular, and cancer mortality: a systematic review and dose-response meta-analysis of prospective cohort studies

Considerable controversy exists regarding the association between calcium intake and mortality risk. Therefore, this study aimed to summarize available findings on the associations of total, dietary and supplemental calcium intake with all-cause, CVD, and cancer mortality. We searched PubMed, Scopus, Embase, and ISI Web of Knowledge until February 2020 to identify eligible publications. Random-effects models were used to calculate pooled effect sizes (ESs) and 95% confidence intervals (CIs) for highest versus lowest categories of calcium intake and to incorporate variation between studies. Linear and non-linear dose-response analyses were done to evaluate the dose-response relations between calcium intake and mortality. 36 publications were included in this systematic review and 35 in the meta-analysis. During the follow-up periods ranging from 4.2 to 28 years, the total number of deaths from all causes was 163,657 (83703 from CVD and 83929 from cancer). Total calcium intake was associated with a lower risk of CVD mortality (Pooled ES for highest v lowest category: 0.91; 95% CI: 0.83-0.99, I²=68.1%, P < 0.001). Dietary calcium intake was associated with a lower risk of all-cause mortality (Pooled ES for highest v lowest category: 0.95; 95% CI: 0.92-0.99, I²=62.1%, P < 0.001). Supplemental calcium intake was not significantly associated with risk of all-cause, CVD and cancer mortality. In the dose-response analysis, there was evidence of nonlinear association between calcium intake and risk of all-cause, CVD, and cancer mortality. In conclusion, a non-linear association between calcium intake with all-cause, CVD, and cancer mortality risk was observed in this meta-analysis. Moderate intake of total (1000-1800), dietary (600-1200), and supplemental calcium (600-1200) was inversely significantly associated with mortality risk but higher calcium intake was not associated with a lower risk of mortality.

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

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

The vitamin D and calcium controversy: an update

PURPOSE OF REVIEW

Calcium and vitamin D supplementation is widely recommended for prevention of falls and fracture, particularly in the elderly where calcium intakes and vitamin D levels are often inadequate. A number of meta-analyses have questioned the benefits of untargeted or 'holistic' supplementation for falls and fracture, and raised the possibility of adverse cardiovascular effects. This review provides an update on these controversies.

RECENT FINDINGS

Recent advances have largely centred around new trials of vitamin D and meta-analyses of published trials and observational studies. These articles have identified holistic vitamin D supplementation with or without calcium is unlikely to be an effective primary prevention strategy for falls or fracture. There has also been high-quality evidence that vitamin D, daily or as a bolus, does not reduce the risk of cardiovascular events.

SUMMARY

The benefits of vitamin D and calcium supplements for holistic fall and fracture prevention remain uncertain. Recent evidence supports the concept that high-dose vitamin D has adverse musculoskeletal effects. Future studies should focus on moderate daily doses. Finally, there remain inconsistent findings for adverse cardiovascular effects of calcium supplements with or without vitamin D. This uncertainty should be taken into account when evaluating the risk/benefits of supplementation.