A population‐based prospective study of energy‐providing nutrients in relation to all‐cause cancer mortality and cancers of digestive organs mortality

Abstract

The effect of dietary composition on mortality in low income countries is largely unknown. We evaluated whether percentages of dietary energy derived from protein, fat, and carbohydrates were associated with all-cause and cancer mortalities in a Bangladeshi population. Data from a prospective population-based cohort study of 17,244 men and women were used. Percentages of dietary energy derived from protein, fat, and carbohydrates, assessed using a validated food-frequency questionnaire at baseline, were analyzed in relation to mortality over an average of 9 years (155,126 person-years) of follow-up. Cox proportional hazards regression models were used to estimate hazard ratios for all cause, all cancer, and cancers of the digestive organs mortalities. Percentage of dietary energy from protein appeared to be significantly associated with cancer mortality. Fully adjusted hazard ratios for cancer mortality in increasing tertiles of percentage of dietary energy from protein were 1.0 (reference), 1.21 (0.73, 2.00), and 1.84 (1.08, 3.15) (P for trend = 0.023). These associations were much stronger for deaths from cancers of the digestive organs with fully adjusted hazard ratios in increasing tertiles of percentage of dietary energy from protein being 1.0 (reference), 2.25 (0.91, 5.59), and 4.85 (1.88, 12.51) (P for trend = 0.001). No significant associations in relation to cancer-related mortality were observed for percentage of dietary energy from fat. Novel findings from this prospective study show protein is an important risk factor or proxy to an important risk factor for cancer mortality especially from digestive organ cancers in Bangladesh.

Dietary intake of total, animal, and plant proteins and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies

“…Finally, 32 papers of cohort studies were included in the systematic review,79101112131415161718454647484950515253545556575859606162636465 and 31 papers were included in this meta-analysis 791011121314151617184546474849505152535455565758596061636465. Twenty two papers reported effect sizes for all cause mortality,791011121314151617184647495051525455596365 17 for cardiovascular disease mortality,91011131415161718…”

“…Twenty two papers reported effect sizes for all cause mortality,791011121314151617184647495051525455596365 17 for cardiovascular disease mortality,910111314151617184749505153575864 and 14 for cancer mortality 79131415161718454648566061. Of these publications, 26 had reported effect sizes for intake of total protein,79101214161718454647484950515253545556596061636465 16 for intake of animal protein,7910121314151618454956586162…”

“…Others also adjusted for physical activity (n=14), energy intake (n=25), other dietary variables (n=14), and macronutrients (fat or carbohydrate; n=12). Based on the ROBINS-E tool, 15 articles had a low risk of bias in all components (supplementary table 2) 71112131415161718465155626364. Nine papers provided effect sizes for mortality from cardiovascular disease and cancer, without reporting any effect size for all cause mortality 104548535657586061.…”

“…Twelve papers,91314151618454648566061 with a total of 292 629 participants and 22 118 deaths, examined the association between intake of total protein and cancer mortality. The summary effect size for cancer mortality comparing the highest and lowest protein intakes was 0.98 (95% confidence interval 0.92 to 1.05, P=0.63), indicating no clear association; however, evidence of moderate heterogeneity was found between studies (I 2 =40.9%, P=0.06; fig 4).…”

“…Eight 910161718465164 of 21 publications on the association between total protein intake and all cause mortality were included in the dose-response analysis (fig 5). No significant non-linear association was found (P=0.40 for non-linearity).…”