Two clinical experiments were carried out in order to establish a relation between restricted calorie intake and life span in monkeys. After initial conflicts between results, researchers concluded affirmative results suggesting reducing calorie intake might improve longevity.
Eat less and stay healthy
The old school health rhyme is never a different story, even a century old guy would ask you to eat less and add more veggies to skip maladies, without the aid of modern day technology or researches. But some scientists took this idea into next level by giving it a clinical try on living beings. There were actually two studies based on the notion that restricting calorie intake for a long period of time would improve the life span. However, the claim was put to test in order to confirm the validity – thanks to Rhesus monkeys. Even without these studies, 5000 years old Indian Ayurveda recommends to ditch meat and replace them with healthy veggies which are superior in nutrition and improve the lifespan.
About the studies
Both studies are pulled two decades back and traveled along with the timeline in order to make their results fool proof. The first was carried out by a team from National Institute of Aging (NIA) in the year 1987 and second one by another team from University of Wisconsin-Madison (UW). The NIA team used a different diet but the same approach as that of UW team. NIA fed the monkeys 30% less food than the control, whereas UW team also did same but in a slightly different manner. After 20 years through the experiment, UW team came with an affirmative news however the NIA results stood discrepant.
Facing the discrepancy
While both institutions did same research, they concluded different results. UW team found that monkeys under restriction were found to live longer than their control counterpart with less susceptibility to cardiac diseases, cancer, or insulin resistance. Contrary to UW conclusion NIA announced that diet has no effect on the longevity of the primates in their study. In order to account the dissimilarity, a team from both institutions started a combined scrutiny of their results. On digging the depth they were able to understand that factors like age, sex & diet might have influenced the results. While NIA test group had monkeys of all ages, UW group used 8-year-old adult monkeys for their study. Also, the NIA diet was natural, which included seasonal foods & they only hinged on the calorie restriction, however, UW diet was semi-purified giving more stress to protein and fibers with lower fat, which was fed consistently as such throughout the end of the study.
After scrutinizing both the results NIA team finally concluded that on a wider basis, taking into account the UW study and other influencing factors, monkeys might have an improved life span, contradictory from their studies. Also, they observed that male monkeys possess more risk of ill health compared to female ones. But the study is yet to confirm its efficacy in humans, even though monkeys are a close companion in clinical studies. When it comes to us, apart from sex, diet and age many other social, psychological and physiological factors might influence this result. But in a nutshell ‘restricting calorie intake improves the longevity in nonhuman primates’.
Caloric restriction improves health and survival of rhesus monkeys.
Mattison JA, Colman RJ, Beasley TM, Allison DB, Kemnitz JW, Roth GS, Ingram DK, Weindruch R, de Cabo R, Anderson RM.
Nat Commun. 2017 Jan 17; 8:14063. [PMID:28094793]