Animal or Vegetable? Protein Source and Mortality Risk Examined
HealthDay News — People who get more of their protein from plant sources have an overall lower mortality risk than those who consume more animal protein, according to research published online August 1 in JAMA Internal Medicine.
Mingyang Song, MD, ScD, a nutrition research fellow with the Harvard T.H. Chan School of Public Health in Boston, and colleagues analyzed data from two large U.S. studies that regularly tracked participants' diets during as much as three decades of follow-up. The studies involved 131,342 individuals whose daily calorie intake averaged 14% animal protein and 4% plant protein.
The researchers found that for every 3% increase in plant protein in their daily diet, participants experienced a 10% lower risk of all-cause mortality and a 12% lower risk of cardiovascular-related mortality. Participants experienced a 2% increased risk of all-cause mortality and an 8% increased risk of cardiovascular-related mortality for every 10% increase of animal protein in their total daily calories. Swapping 3% of calories from animal protein with plant protein lowered overall risk of premature death, based on the type of animal protein being substituted. Risk of early mortality dropped 34% if people ate less processed red meat, 12% for less unprocessed red meat, and 19% for fewer eggs.
The increased risk of death linked to animal protein only occurred in people with other unhealthy lifestyle traits, such as obesity, heavy drinking, smoking, or lack of exercise, the study authors noted. The association disappeared in participants with a healthy lifestyle. The study also found mixed results regarding eggs and dairy products, which were not as bad as processed or red meats but were not as good as chicken or fish, Song told HealthDay. "When you compare egg and dairy to red meat, they can be considered a good source, but fish or chicken would be a better source," he said.