Purpose of review: To examine the role of two nutritional factors implicated in the healthy aging of the Okinawans: caloric restriction; and traditional foods with potential caloric restriction-mimetic properties.
Recent findings: Caloric restriction is a research priority for the US National Institute on Aging. However, little is known regarding health effects in humans. Some caloric restriction-related outcomes, such as cause-specific mortality and lifespan, are not practical for human clinical trials. Therefore, epidemiological data on older Okinawans, who experienced a caloric restriction-like diet for close to half their lives, are of special interest. The nutritional data support mild caloric restriction (10–15%) and high consumption of foods that may mimic the biological effects of caloric restriction, including sweet potatoes, marine-based carotenoid-rich foods, and turmeric. Phenotypic evidence is consistent with caloric restriction (including short stature, low body weight, and lean BMI), less age-related chronic disease (including cardiovascular diseases, cancer, and dementia), and longer lifespan (mean and maximum).
Summary: Both caloric restriction and traditional Okinawan functional foods with caloric restriction-mimetic properties likely had roles in the extended healthspan and lifespan of the Okinawans. More research is needed on health consequences of caloric restriction and foods with caloric restriction-mimetic properties to identify possible nutritional interventions for healthy aging.
aDepartment of Geriatric Medicine, John A. Burns School of Medicine, University of Hawaii
bDepartment of Research, Kuakini Medical Center, Honolulu, Hawaii, USA
cDepartment of Human Welfare, Okinawa International University, Ginowan, Okinawa, Japan
Correspondence to Bradley J. Willcox, MD, Department of Geriatric Medicine, John A. Burns School of Medicine, University of Hawaii, Kuakini Medical Center Campus, 347 N. Kuakini Street, HPM-9, Honolulu, HI 96817, USA. Tel: +1 808 523 8461; fax: +1 808 528 1897; e-mail: email@example.com