Estimates of animal and plant protein intake in US adults: Results from the Third National Health and Nutrition Examination Survey, 1988-1991

Objective To describe the sources of protein intake in a sample of the US a dult population and among subgroups defined by race-ethnicity, age, and gen der. Design The Third National Health and Nutrition Examination Survey, 1988-199 1, is a stratified random sample of the total civilian noninstitutionalized population, drawn from the 50 United States and the District of Columbia. For all foods consumed by the participants, based on a 24-hour dietary reca ll, protein sources and the contribution of each protein type to the total protein intake were determined. Subjects Adult participants in the third National Health and Nutrition Exam ination Survey (n = 7,924). Statistical analyses Weighted total, age-specific, and age-adjusted mean pr otein intakes were calculated using SAS and WesVarPC. Statistical differenc es were determined by 2-tailed t tests. Results The main protein source in the American diet is animal protein (69% ). Meat, fish, and poultry protein combined contributed the most to animal protein (42%), followed by dairy protein (20%). Grains (18%) contributed th e most to plant protein consumption. Women consumed a lower percentage of b eef (14%) and pork (7%) protein than did men (18% and 9%, respectively). Wo men also consumed a higher percentage of poultry (13%), dairy (22%), and fr uit and vegetable (11%) protein than did men (11%, 19%, and 9%, respectivel y). Blacks reported eating a higher percentage of poultry (18%) and pork (1 1%) protein and a lower percent of dairy protein (14%) than did whites (12% , 7%, and 22%, respectively) and Mexican-Americans (11%, 8%, and 17%, respe ctively). Mexican-Americans consumed a higher percentage of legume (7%) and egg (7%) protein than did whites (4% and 4%, respectively) and blacks (4% and 5%, respectively). Whites consumed a higher percentage of grain protein (19%) than did blacks (16%) and Mexican-Americans (15%). Conclusions These results show that, although the percentage of total energ y from protein may be similar among race-ethnicities and between men and wo men, their sources of protein are different. These differences should be ta ken into account when providing nutrition education for specific population s.