What is the relationship between vegetable protein and/or soy protein and selected health outcomes?

Summary of the review:

The Carbohydrate and Protein Subcommittee (SC) chose to consider a question addressing vegetable protein and health to parallel their review of animal protein products. The search captured literature published from 2000 to present. This date range was selected because the question was not addressed by the 2005 Dietary Guidelines Advisory Committee (DGAC), and the same date range was used for the animal protein search. Because much of the research on vegetable protein has considered soy protein, soy protein was included in the search as a separate term. However, articles examining soy foods, rather than soy protein specifically, were considered under the SC’s review of cooked dry beans and peas. For all of the health outcomes, except cancer, the search was not limited regarding study design. The SC only considered prospective cohort studies for the cancer outcome (colorectal, breast, and prostate) to be consistent with the review completed for animal protein products. A variety of health outcomes were included in the search. Based on the research available, the final health outcomes considered were chronic disease, blood pressure (BP), blood lipids, and body weight. The SC limited their review to studies that included healthy participants (e.g., studies that only included participants with hyperlipidemia were excluded). Because there was limited research available on this topic, the SC included all study designs (including cross-sectional) in their review (with the exception of cancer, as described previously).