The relationship between lean mass and protein intake in females of African and East Asian descent

Low lean mass (LM) is associated with increased cardiometabolic disease risk and increased injury risk. Protein (PRO) intake is an important strategy to build and maintain LM. There is limited data quantifying PRO intake and evaluating the association between PRO intake and LM in non-athletic, young adult, female populations, and even less in females of color. The purpose of this study was to characterize PRO intake and evaluate the association between PRO intake and LM in females of color. Eighty-five females of African ( n = 42) and East Asian ( n = 43) descent (Age: 22.5 ± 3.8 yrs, BMI: 23.8 ± 3.5 kg/m 2 ) completed this study. Participants completed a 3-day dietary log. A dietary analysis software assessed total caloric intake, total PRO intake and PRO intake as a percentage of total calories (%PRO). LM was assessed using dual-energy x-ray absorptiometry. Multiple linear regression analyses were performed to assess the association between PRO intake and LM, after controlling for potential confounding variables (e.g., ethnicity, age, MVPA). For the full sample, PRO intake was 86.1 ± 30.0 g and %PRO was 17.4 ± 4.8%. After controlling for age, MVPA and ethnicity, both PRO intake (b = 0.07, 95% CI [0.03, 0.11], p < 0.001) and %PRO (b = 0.29, 95% CI [0.06, 0.53], p = 0.014) were independently associated with LM. There were no significant interaction effects between ethnicity and PRO (b = -0.03, 95% CI [-0.10–0.05], p = 0.461) or %PRO (b = -0.01, 95% CI [-0.11– 0.09], p = 0.803). In this ethnically diverse sample of young-adult females, PRO intake and %PRO were within recommended guidelines to support LM. Higher total PRO intake and %PRO were associated with greater LM, suggesting that protein intake may be an important modifiable factor associated with LM in young adult females of color.