Table 3.
Multiple Linear Regression Models of Muscle Mass and Lean Mass With Nutritional Variables in Older Men (n = 903)
| D3Cr Muscle Mass (kg) | D3Cr Muscle Mass/Weight | DXA Appendicular Lean Mass (kg) | ||||
|---|---|---|---|---|---|---|
| Base | Multivariable | Base | Multivariable | Base | Multivariable | |
| Carbohydrate (%TEI) | −0.11 (−0.17, −0.06)*** | −0.09 (−0.15, −0.04)** | 0.02 (−0.05, 0.08) | −0.06 (−0.11, −0.01)* | −0.06 (−0.13, 0.001) | −0.03 (−0.09, 0.02) |
| Fat (%TEI) | 0.08 (0.02, 0.14)* | 0.06 (0.004, 0.12)* | −0.05 (−0.11, 0.01) | 0.03 (−0.02, 0.08) | 0.07 (0.004, 0.13)* | 0.04 (−0.02, 0.09) |
| Total protein (%TEI) | 0.10 (0.04, 0.16)** | 0.09 (0.03, 0.14)** | 0.10 (0.04, 0.16)** | 0.08 (0.03, 0.13)** | −0.005 (−0.07, 0.06) | −0.003 (−0.06, 0.05) |
| Nondairy Animal protein (%TEI) | 0.17 (0.11, 0.23)*** | 0.16 (0.10, 0.21)*** | 0.08 (0.02, 0.14)* | 0.11 (0.07, 0.16)*** | 0.06 (−0.004, 0.12) | 0.06 (0.002, 0.11)* |
| Dairy protein (%TEI) | −0.04 (−0.10, 0.02) | −0.04 (−0.10, 0.02) | −0.04 (−0.10, 0.03) | −0.03 (−0.08, 0.02) | −0.03 (−0.09, 0.04) | −0.04 (−0.09, 0.02) |
| Plant protein (%TEI) | −0.07 (−0.13, −0.01)* | −0.07 (−0.13, −0.02)* | 0.07 (0.01, 0.13)* | −0.02 (−0.07, 0.03) | −0.07 (−0.14, −0.01)* | −0.06 (−0.11, −0.0005)* |
Notes: Base model adjusted for age, clinic site, TEI (total energy intake). Multivariable model adjusted for age, clinic site, TEI, race, education, depression, height, and percent body fat. Effect size (beta-coefficient with unit = SD) and 95% confidence interval. Dietary protein intake is calculated as a percentage of TEI (%TEI) and scaled to have 1 unit change = 3% TEI = SD (total protein intake). Source-specific protein intakes were included in a single model (ie, each one was adjusted for the other two source-specific intakes). SD’s for outcomes and exposures include the following: D3Cr muscle mass 4.01; D3Cr muscle mass/weight 0.05; DXA Appendicular lean mass 3.12; Carbohydrate (%TEI) 0.07; Fat (%TEI) 0.07; Total protein (%TEI) 0.03; nondairy animal protein (%TEI) 0.03; Dairy protein (%TEI) 0.02; Plant protein (%TEI) 0.02.
*p < .05, **p < .01, ***p < .001.