Table 7.

Summary body weight and body composition

				Association of protein/effect (in RCT)
			Number of participants (age) Men (M), Women (W)				Rating A B C
Exposure/Intervention	Outcome variable	Study		Total	Animal	Vegetable		Strength of evidence: Convincing, probable, Suggestive, no conclusion
Frequency of protein consumption (per day/per week)	BMI	Cohort (53)	116 (18–31 years) M and W	NS	NA	NA	C	No conclusion
Quartiles E% of animal and vegetable protein intake	BMI: risk of overweight obesity	Cohort (54)	1,730 (40–55 years) M	NA NA	POS POS	NS INVERSE	C
High protein diet (HP): 1.9 g/kg BW (22 E%) vs.	BMI	Randomized controlled trial (59)	15 (18–36 years) M	NS	NA	NA	C
Normal diet (NP): < 1.3 g/kg BW (15 E%) in 6 months
High protein diet (HP): 1.9 g/kg BW (22 E%) vs.	Body weight change	Randomized controlled trial (59)	15 (18–36 years) M	INVERSE	NA	NA	C	No conclusion
Normal diet (NP): < 1.3 g/kg BW (15 E%) in 6 months
Total, animal and vegetable protein in kcal/day and per 150 kcal/day increments (equal 37.5 g protein)	Change in body weight in gram per year	6 cohorts (56)	89,432 M and W	POS	POS	NS	B
Protein E%	5-yr change in body weight	Cohort (57)	1,762 M and W	NS	NA	NA	B
Protein intake in servings/day	Weight gain of > 10 lb, yes or no	Cohort (58)	336 W	NS	NA	NA	C
15 E% protein vs. 30 E%	Body weight change	Controlled trial (52)	19 M and W	INVERSE	NA	NA	B
E% of total, animal. and vegetable protein	5-y change in waist circumference	Cohort (55)	42,969 M and W	INVERSE	INVERSE	NS	B	No conclusion
Total, animal and vegetable protein in kcal/day and per 150 kcal/day increments (equal 37.5 g protein)	6.5-y-change in waist circumference	Cohort (56)	89,432 M and W	NS	NS	NS	B
High protein diet (HP): 1.9 g/kg BW (22 E%) vs.	Body composition:	Randomized controlled trial (59)	15 (18–36 years) M				C	No conclusion
Normal diet (NP): < 1.3 g/kg BW (15 E%) in 6 months	FFM (kg) FM (kg)			NS NS	NA NA	NA NA