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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #329628

Research Project: Obesity and Energy Regulation throughout the Adult Lifecycle

Location: Jean Mayer Human Nutrition Research Center On Aging

Title: A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

Author
item Ravussin, Eric - Pennington Biomedical Research Center
item Redman, Leanne - Pennington Biomedical Research Center
item Rochon, James - Duke Clinical Research Institute
item Das, Sai - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item Fontana, Luigi - Washington University School Of Medicine
item Kraus, William - Duke Clinical Research Institute
item Romashkan, Sergei - National Institute On Aging (NIA, NIH)
item Williamson, Donald - Pennington Biomedical Research Center
item Meydani, Simin - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item Villareal, Dennis - Washington University School Of Medicine
item Smith, Steven - Pennington Biomedical Research Center
item Stein, Richard - Washington University School Of Medicine
item Scott, Tammy - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item Stewart, Tiffany - Pennington Biomedical Research Center
item Saltzman, Edward - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item Klein, Samuel - Washington University School Of Medicine
item Bhapkar, Manju - Duke Clinical Research Institute
item Martin, Corby - Pennington Biomedical Research Center
item Gilhooly, Cheryl - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item Holloszy, John - Washington University School Of Medicine
item Hadley, Evan - National Institute On Aging (NIA, NIH)
item Roberts, Susan - Jean Mayer Human Nutrition Research Center On Aging At Tufts University

Submitted to: Journal of Gerontology Medical Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2015
Publication Date: 9/1/2015
Citation: Ravussin, E., Redman, L.M., Rochon, J., Das, S.K., Fontana, L., Kraus, W.E., Romashkan, S., Williamson, D.A., Meydani, S.N., Villareal, D.T., Smith, S.R., Stein, R.I., Scott, T.M., Stewart, T.M., Saltzman, E., Klein, S., Bhapkar, M., Martin, C.K., Gilhooly, C.H., Holloszy, J.O., Hadley, E.C., Roberts, S.B. 2015. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity. Journal of Gerontology Medical Science. 70(9):1097-1104.

Interpretive Summary: An ad libitum diet is one in which food intake is self-regulated or freely chosen. Long-term caloric restriction (CR), defined as a reduction in energy intake by a specified amount below ad libitum intake, increases life span and health span in many species. To determine CRs feasibility, safety, and effects on predictors of longevity, disease risk factors, and quality of life in non-obese young to middle age humans, 218 persons were randomized to a two-year intervention designed to achieve 25% CR or to ad libitum diet (AL). Compared to AL, CR had larger decreases in cardiometabolic risk factors and in daily energy expenditure adjusted for weight change, without adverse effects on quality of life. Sustained CR is feasible in non-obese humans. The effects of the degree of CR in this study on reported predictors of human survival (e.g., daily energy expenditure and thyroid function) and chronic disease risk factors suggest potential favorable effects on aging related outcomes that could be elucidated by further human studies.

Technical Abstract: Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, disease risk factors, and quality of life in non-obese humans aged 21-51 years, 218 persons were randomized to a two-year intervention designed to achieve 25% CR or to AL diet. Outcomes were change from baseline resting metabolic rate adjusted for weight change (RMR residual) and core temperature (primary); plasma triiodothyronine (T3) and tumor necrosis factor alpha (secondary); and exploratory physiological and psychological measures. Results: Body mass index averaged 25.1 (range: 21.9 - 28.0 kg/m2). Eighty two percent of CR and 95% of AL participants completed the protocol. The CR group achieved 11.7 +/- 0.7%CR (mean +/- standard error) and maintained 10.4 +/- 0.4% weight loss. Weight change in AL was negligible. RMR residual decreased significantly more in CR than AL at 12 months (p=.04) but not 24 months (M24). Core temperature change differed little between groups. T3 decreased more in CR at M12 and M24 (p < .001), while tumor necrosis factor alpha decreased significantly more only at M24 (p=.02). CR had larger decreases in cardiometabolic risk factors and in daily energy expenditure adjusted for weight change, without adverse effects on quality of life. Conclusions: Sustained CR is feasible in nonobese humans. The effects of the achieved CR on correlates of human survival and disease risk factors suggest potential benefits for aging related outcomes that could be elucidated by further human studies.