ASSOCIATION OF ANIMAL AND PLANT PROTEIN INTAKE WITH ALL-CAUSE AND CAUSE-SPECIFIC MORTALITY
Mingyang Song, MD, ScD1,2; Teresa T. Fung, ScD2,3; Frank B. Hu, MD, PhD2,4,5; et alWalter C. Willett, MD, DrPH2,4,5; Valter D. Longo, PhD6,7; Andrew T. Chan, MD, MPH1,5,8; Edward L. Giovannucci, MD, ScD2,4,5
JAMA Intern Med. 2016;176(10):1453-1463.
Ronald Peters MD Comments:
No news flash here. Once again, a significant prospective study looking at the lifestyle and dietary patterns of 131,341 health professionals over 32 years showed that eating plant protein reduced the risk of heart disease, and, death from all causes, while animal protein intake increased the risk for heart disease. Numerous other studies have shown that plant protein, unlike animal protein, is linked to lower blood pressure, reduced LDL, and improved insulin sensitivity. A lot of research has also shown that substitution of plant protein for animal protein has been related to lower incidence of cardiovascular disease and type 2 diabetes. We have known much of this since 2004 when The China Study was published. Dr T. Colin Campbell of Cornel University, along with Oxford University and numerous Chinese universities studied 200 million people for 20 years and, clearly showed that eating animal products of any kind increased the risk for chronic illness, including heart disease and cancer.
But we live in a society in which the food industry is adopting the techniques of the tobacco industry to insure profit and our media is more devoted to its corporate sponsors than providing the truth.
Abstract
Importance Defining what represents a macronutritionally balanced diet remains an open question and a high priority in nutrition research. Although the amount of protein may have specific effects, from a broader dietary perspective, the choice of protein sources will inevitably influence other components of diet and may be a critical determinant for the health outcome.
Objective To examine the associations of animal and plant protein intake with the risk for mortality.
Design, Setting, and Participants This prospective cohort study of US health care professionals included 131 342 participants from the Nurses’ Health Study (1980 to end of follow-up on June 1, 2012) and Health Professionals Follow-up Study (1986 to end of follow-up on January 31, 2012). Animal and plant protein intake was assessed by regularly updated validated food frequency questionnaires. Data were analyzed from June 20, 2014, to January 18, 2016.
Main Outcomes and Measures Hazard ratios (HRs) for all-cause and cause-specific mortality.
Results Of the 131 342 participants, 85 013 were women (64.7%) and 46 329 were men (35.3%) (mean [SD] age, 49 [9] years). The median protein intake, as assessed by percentage of energy, was 14% for animal protein (5th-95th percentile, 9%-22%) and 4% for plant protein (5th-95th percentile, 2%-6%). After adjusting for major lifestyle and dietary risk factors, animal protein intake was not associated with all-cause mortality (HR, 1.02 per 10% energy increment; 95% CI, 0.98-1.05; Pfor trend = .33) but was associated with higher cardiovascular mortality (HR, 1.08 per 10% energy increment; 95% CI, 1.01-1.16; P for trend = .04). Plant protein was associated with lower all-cause mortality (HR, 0.90 per 3% energy increment; 95% CI, 0.86-0.95; P for trend < .001) and cardiovascular mortality (HR, 0.88 per 3% energy increment; 95% CI, 0.80-0.97; P for trend = .007). These associations were confined to participants with at least 1 unhealthy lifestyle factor based on smoking, heavy alcohol intake, overweight or obesity, and physical inactivity, but not evident among those without any of these risk factors. Replacing animal protein of various origins with plant protein was associated with lower mortality. In particular, the HRs for all-cause mortality were 0.66 (95% CI, 0.59-0.75) when 3% of energy from plant protein was substituted for an equivalent amount of protein from processed red meat, 0.88 (95% CI, 0.84-0.92) from unprocessed red meat, and 0.81 (95% CI, 0.75-0.88) from egg.
Conclusions and Relevance High animal protein intake was positively associated with cardiovascular mortality and high plant protein intake was inversely associated with all-cause and cardiovascular mortality, especially among individuals with at least 1 lifestyle risk factor. Substitution of plant protein for animal protein, especially that from processed red meat, was associated with lower mortality, suggesting the importance of protein source.