What do the residents of the Mediterranean island of Sardinia, the inhabitants of the sub-tropical archipelago of Okinawa, and Seventh-day Adventists have in common? They all have an unusually high number of centenarians and a higher than normal average life expectancy.

Among the centenarians, what are the common lifestyle elements in these three genetically diverse population groups? Well, their diet is essentially vegetarian, they are physically active, don’t smoke, put family first, have a good social support system, and have a positive attitude about life.

Their lifestyles do not lead to an excessive body weight. In the Okinawan Centenarian Study they found elderly Okinawans don’t normally overindulge. They live by the Confucian-inspired adage hara hachi bu—eat until the stomach is 80 percent full. Furthermore, their diet is rich in high-fiber foods, such as fruits and vegetables.

Dietary restriction of calories is well known to slow the aging process and maintain health and vitality into old age. Research with experimental animals found that lowering caloric intake by one-third reduced disease and signs of aging in the animals, and increased their lifespan by 50 percent. However, it would be very difficult to get humans to maintain a 30 to 40 percent reduction in food intake necessary to add decades to their lives.

Extending life wouldn’t mean a whole lot if it simply meant living extra years with more disease, increased disabilities, and without much quality to life. What we actually find is that the same lifestyle changes that add years to your life can also add life to your years. Studies reveal that those with few health risks (such as stroke and heart disease) have only one-fourth the disability of those who have more risks, and the onset of disability is postponed from seven to 12 years.

Recently, a number of studies demonstrated that older people can achieve longevity with minimal sickness, provided they remain physically and mentally active. When 800 elderly persons were followed for eight years, they found those who didn’t exercise developed three and a half times more disabling ailments than those who maintained a regular exercise program. Exercise also improves mood. Those who exercise have significantly less stress, anxiety, and depression—common complaints among the elderly.

Good health habits don’t guarantee a long life, they just increase the likelihood of living longer and better. Studies show that the earlier in life bad lifestyle habits are changed, the greater the benefit to one’s overall well-being.

Winston Craig is professor of nutrition at Andrews University.

Regular exercise keeps you young and healthy.

Caloric restriction significantly increases lifespan.

Lifestyle changes that add years to your life can also add life to your years.