• Research Review
• Journal Review

Authors: R Sinha, AJ Cross, BI Graubard, MF Leitzmann, A Schatzkin

Reference: Arch Intern Med 2009; 169: 562-571, http://archinte.ama-assn.org/cgi/content/full/169/6/562 (open access)

Reviewer: Robert Goldberg, PhD, Contributing editor, ProCor; Professor of Medicine and Epidemiology, Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA

Problem addressed: Consumption of different types of meat and all-cause, and cause-specific mortality rates.

Purpose of study: To examine the relation between consumption of red, white, and processed meats with all-cause and cause-specific mortality in middle-aged and elderly adults.

Location of study: United States

Study design: The authors used data from the National Institutes of Health - American Association of Retired Persons Study. The study population consisted of more than 600,000 individuals aged 50-71 years who were recruited from six US states and two large metropolitan areas (Atlanta, Georgia, and Detroit, Michigan). Information was collected at the time of baseline enrollment in the mid-1990s about the demographic and lifestyle characteristics as well as dietary habits of the study population. The dietary assessment consisted of a 124 item food frequency questionnaire which asked questions about a variety of foods and drinks, as well as portion sizes, that survey respondents reported consuming during the past 12 months. Questions were asked about the intake of red meats (e.g., beef, cold cuts, hamburger, hot dogs), white meats (chicken, turkey, canned fish), and processed meats (e.g., bacon, sausage, luncheon meats).

The study cohort was followed from 1995 through the end of 2005 through a variety of means. Mortality from all causes and from specific causes of death was assessed; deaths from CVD were examined and mortality from CVD included a combination of deaths from CHD, cerebrovascular disease, and other related causes.

Results: The average age of the study sample was in their early 60s, more than one half were men, the majority were Caucasian and currently married, and the average daily caloric intake was approximately 2000 calories.

Over the 10 years of follow-up, nearly 48,000 men and more than 23,000 women died from all causes. There were more than 14,000 deaths attributed to CVD in men and a relatively similar number of deaths due to CVD that occurred in the sample of women studied.

With regards to the consumption of red meat, there was an overall increased risk of all-cause and CVD-related mortality in both men and women for those in the uppermost quintile of reported red meat consumption compared with those in the lowest quintile of red meat intake. With regards to CVD mortality, persons in the uppermost quintile of self-reported red meat consumption experienced a 27% higher risk of dying from CVD related causes (RR = 1.27; 95% CI 1.20, 1.35) in comparison to those in the lowest quintile of red meat consumption. Relatively similar associations were observed with respect to the consumption of processed meats with all-cause and CVD-related mortality; there was a multivariable adjusted 38% greater likelihood of dying from CVD among those in the uppermost quintile of processed meat consumption compared with those in the lowermost referent quintile (adjusted RR = 1.38; 95% CI 1.26, 1.51).

On the other hand, there was an inverse association between the consumption of white meat (e.g., chicken, turkey, and fish) and all-cause mortality. There was essentially no relation between the self-reported consumption of white meat with CVD related mortality after adjustment for several potentially confounding prognostic factors (RR = 1.05; 95% CI 1.00, 1.11).

In calculating population-attributable risks, it was estimated that 11% of all deaths in men, and 16% of deaths in women, could be prevented if persons decreased their consumption of red meat to the levels of those noted in persons who were represented in the first quintile of the present study. Similarly, it was estimated that 11% of the deaths from CVD observed in men, and 21% of the deaths attributed to CVD in women, would be eliminated if the intake of red meat was decreased to the amount consumed by individuals in the first quintile of the present study.

Comments: The results of the present study suggest relatively modest increases in all-cause and CVD-related mortality in middle-aged and elderly men and women consuming higher intakes of red and processed meats over the course of an extended 10-year follow-up.

These findings are consistent with the results of other large prospective studies which have suggested that persons who consume lower amounts of red meat and processed meats are at lower risk for total mortality. These results suggest that physicians and nutritionists should counsel their patient populations to reduce the amount of red meat and processed meats that they consume to smaller amounts for purposes of reducing their overall risk of dying and specifically that from CVD. This is a reasonable public health message that should be delivered to patients with various chronic diseases as well as to the general public.

In an accompanying editorial to this article, the benefits on the world's health and available resources through reduced meat consumption were also thoughtfully reviewed as there are multiple benefits to be gained from lowering the global intake of animal and processed meats (1). Considerable health benefits have been repeatedly demonstrated through the regular consumption of fresh fruits and vegetables, several servings of fish and chicken on a weekly basis, and consumption of small amounts of meat. These broad dietary recommendations, which have particularly beneficial effects on lowering the risk of CHD, are consistent with the results of the present study which suggest that the consumption of red and processed meats in small amounts may pay considerable health dividends.

Citations:

1. Popkin BM. Reducing meat consumption has multiple benefits for the world's health. Arch Intern Med 2009; 169: 543.