Calorie restriction reduces adverse effects of aging. Scientists at Pennington Biomedical Research conducted the first study on calorie restriction in non-obese humans. Fifty-three healthy people between the ages of 21 and 50 cut their calorie intake by 15 percent over the course of two years. On average, the participants lost about 9 kg, but there was no prescribed diet and the goal was not weight loss, but rather to study the effect on aging. No adverse effects were noted, and instead, participants reported improved mood and health-related quality of life. Furthermore, and perhaps most revealing, the decreased calorie intake led to lowered oxidative stress, something that has been proven to lead to age-related diseases such as Alzheimer’s, Parkinson’s, cancer, diabetes, and rheumatoid arthritis

A healthy social life as a young person is linked to better physical health in adulthood. It has long been suspected that a healthy social life has both current and lasting effects on one’s physical health, but a recent study published by the Association of Psychological Science confirms this and suggests that more quality time spent with friends in childhood has the most significant effect on physical health in adulthood. The more time young boys spent with friends in childhood (as reported by their parents at the time, beginning at age 6), the lower their blood pressure and BMI as 32-year-old adults. The findings were consistent among 267 participants, across races and social classes, and this longitudinal study controlled for other factors such as personality or weight in childhood and adulthood. However, the study must be repeated with females, a larger sample, and more physiological measures to be certain of the link between time spent with friends in childhood and better physical health in adulthood