Source: JAMA August 01, 2016

This study analyzed data from more than 130,000 participants over 32 years to identify associations of different animal and plant protein sources with risks for mortality. After they adjusted for dietary and lifestyle factors, researchers found that higher animal protein intake was associated with higher risk for mortality, particularly from cardiovascular disease, while higher consumption of plant protein was associated with lower mortality from all causes. These associations were true only for participants with at least one of the following risk factors: smoking, heavy alcohol intake, obesity, and physical inactivity.

When participants substituted plant protein for animal protein, their mortality risk decreased, especially when the participant had been a heavy consumer of processed red meat. Overall, the reduction of processed red meat consumption showed a much stronger association with reduced mortality than reduction of fish and poultry consumption. When protein was substituted for other nutrients (for example, carbohydrates), the source of that protein appeared to be even more important. It is clear that the choice of protein sources may be a key determinant in health outcomes and that public health recommendations should emphasize improvement of protein sources.