Higher protein intake preserves lean mass and satiety with weight loss in pre-obese and obese women.
OBJECTIVE
To examine the effects of dietary protein and obesity classification on energy-restriction-induced changes in weight, body composition, appetite, mood, and cardiovascular and kidney health.


METHODS
Forty-six women, ages 28 to 80, BMI 26 to 37 kg/m(2), followed a 12-week 750-kcal/d energy-deficit diet containing higher protein (HP, 30% protein) or normal protein (NP, 18% protein) and were retrospectively subgrouped according to obesity classification [pre-obese (POB), BMI = 26 to 29.9 kg/m(2); obese (OB), BMI = 30 to 37 kg/m(2)).


RESULTS
All subjects lost weight, fat mass, and lean body mass (LBM; p < 0.001). With comparable weight loss, LBM losses were less in HP vs. NP (-1.5 +/- 0.3 vs. -2.8 +/- 0.5 kg; p < 0.05) and POB vs. OB (-1.2 +/- 0.3 vs. -2.9 +/- 0.4 kg; p < 0.005). The main effects of protein and obesity on LBM changes were independent and additive; POB-HP lost less LBM vs. OB-NP (p < 0.05). The energy-restriction-induced decline in satiety was less pronounced in HP vs. NP (p < 0.005). Perceived pleasure increased with HP and decreased with NP (p < 0.05). Lipid-lipoprotein profile and blood pressure improved and kidney function minimally changed with energy restriction (p < 0.05), independently of protein intake.


CONCLUSIONS
Consuming a higher-protein diet and accomplishing weight loss before becoming obese help women preserve LBM. Use of a higher-protein diet also improves perceptions of satiety and pleasure during energy restriction.
Leidy
Heather J
HJ
Department of Foods and Nutrition, Ingestive Behavior Research Center, Purdue University, West Lafayette, Indiana, USA. hleidy@purdue.edu
Carnell
Nadine S
NS
Mattes
Richard D
RD
Campbell
Wayne W
WW
D000328:Adult; D000339:Affect; D001066:Appetite; D001823:Body Composition; D001835:Body Weight; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D009765:Obesity / Q000178:diet therapy*; D012527:Satiation; D015431:Weight Loss
D004044:Dietary Proteins