Table 1.

Comparison of Methods: NIA and Wisconsin NHP CR Studies

Study Attribute		NIA	UW
Animal origin/ genetics		Indian & Chinese	Indian
Age of onset
	Males (age range)	Early- (1 – 5 yrs), Old- (>15 yrs)	Adult- (6 – 14 yrs)
	Females (age range)	Early- (1 – 5 yrs), Adult- (6 – 14 yrs), Old- (>15 yrs)	Adult- (6 – 14 yrs)
Control ration basis		Published standards	Individual baseline intake
Feeding practices
	Meals per day	2	1
	Overnight access	Yes	No
Feeding regimen		Limited daily	Limited daily
Source of diet		Natural	Semi-purified
	Fat	Soy, corn, fish oils	Corn oil
Nutrient content
	Sucrose (% of total carbs)	< 7	45

Methodological characteristics of the NIA and Wisconsin longitudinal calorie restriction studies in nonhuman primates (48,49).