Red, processed meats tied to all-cause mortality
High consumption of red and processed meats is linked to higher mortality in individuals above 45 years of age, a new prospective study shows. On the other hand, there is no significant association between mortality and saturated fatty acid (SFA) intake.
“Our findings … strengthen the importance of limiting meat consumption and to include more explicitly this advice in dietary guidelines addressed to the general public. This could have implications for national dietary policies and guidelines of dietary recommendations,” researchers said.
The dietary habits of 18,540 university graduates were assessed using a semi-quantitative food frequency questionnaire designed to measure intake of red, white, processed and total meat. SFA intake was also measured and adjusted for total energy intake.
Mortality data were obtained mostly from next of kin, the postal system or professional associations. The National Death Index was also consulted for potential deaths in the cohort. Participants were contacted multiple times a year to track changes in postal address.
Over a mean follow-up of 9.5 years, 255 deaths (mean age at death 56.4±15.7 years) were recorded. In participants >45 years, mortality was significantly associated with consumption of red meat (p=0.027). Crude rates of mortality were higher in participants >45 years of age. [Clin Nutr 2017;doi:10.1016/j.clnu.2017.06.013]
Consumption of processed meat (p=0.013) was also significantly correlated with all-cause mortality in individuals >45 years of age, while total meat consumption was moderately significantly associated (p=0.075).
Increasing consumption of red (p=0.012 for trend), processed (p=0.047 for trend), red and processed (p=0.005 for trend), and total (p=0.002) meat showed a significant and positive trend with all-cause mortality after adjustments for age and sex.
The significant and positive trend was retained for red (p=0.022 for trend), red and processed (p=0.018 for trend), and total (p=0.012 for trend) meat consumption after additional adjustments for years of education, BMI, smoking, physical activities, comorbid conditions and other covariates.
“Our observed significant interaction between age and red/processed meat consumption on all-cause mortality has some public health implications. Messages of prevention may not be easily followed by younger persons who are asymptomatic and unaware of the later negative consequences of lifestyle,” said researchers.
“Our results suggest that the general public should become aware of the long-term harmful consequences of excessive meat consumption, and messages should be explicit and plain,” they added.
While SFA intake showed an apparent positive trend with all-cause mortality, none of the associations were statistically significant in both the age- and sex-adjusted (p=0.171 for trend) and multivariate-adjusted (p=0.106 for trend) models.
“This study adds to a large body of evidence linking red meat and particularly processed meat consumption to a higher risk of type 2 diabetes and heart disease,” according to Dr Rob Martinus Van Dam, associate professor and domain leader of the Epidemiology Domain at the Saw Swee Hock School of Public Health in Singapore.
“For example, recently researchers in Singapore showed that higher red meat consumption was associated with a higher risk of type 2 diabetes in Singapore Chinese and that heme iron in meat may contribute to this link,” he added. [Am J Epidemiol 2017;doi:10.1093/aje/kwx156]
In the aforementioned Singapore study, investigators examined the dietary habits of adults enrolled in the Singapore Chinese Health Study and found that higher intake of red meat and poultry was significantly associated with a higher risk of type 2 diabetes.
“Replacement of red meat and poultry by fish/shellfish may reduce [type 2 diabetes] risk, and is worth to be tested in experimental studies,” the investigators said.