Some of us believe that aging is just something that happens to all of us and it’s just a predestined fate, and by the time we turn 65 or 70 or 80, we will have memory loss, and cardiovascular disease, and osteoporosis, and dementia, any of which will make me unable to figure out how to text my grandchild.

But the new research shows on a cellular level the importance of modifiable factors such as healthy diet, and even more so, the importance of regular physical activity.

Poor diet and lax physical activity make you age faster, say Mayo Clinic doctors writing in Diabetes. Their experimental study found cellular evidence for the link between these factors and their biological effects.

Senescent cells are old, damaged cell whose accumulation is the sign of aging. The scientists say exercise prevents premature senescent cell accumulation and protects against the damaging effects of an unhealthy diet including deficiencies in physical, heart and metabolic functions—conditions linked with high blood pressure, cholesterol, body weight and insulin resistance.

In the study, researchers introduced a healthy or fast food diet high in saturated fat and cholesterol with a sugar-sweetened beverage. The fast food group showed harmful changes in body weight and fat composition, increasing fat mass by almost 300% over four months. The fat mass accumulated in the midsection around internal organs. This type of fat accumulation is a hallmark warning sign linked with heart disease and diabetes. Half the groups, including both healthy and unhealthy diets, were given exercise. Those on the fast food diet who exercised showed suppression in body weight gain and fat mass accumulation and were protected against the accumulation of senescent cells. The group on the healthy diet also showed positive effects.

“We think at both a biological level and a clinical level, poor nutrition choices and inactive lifestyles do accelerate aging,” says Nathan LeBrasseur, PhD, director of the Center on Aging’s Healthy and Independent Living Program and senior author of the study. “So now we’ve shown this in very fine detail at a cellular level, and we can see it clinically. And people need to remember that even though you don’t have the diagnosis of diabetes or the diagnosis of cardiovascular disease or the diagnosis of Alzheimer’s disease today when you’re in midlife, the biology underlying those processes is hard at work.

“That doesn’t mean we need to be marathon runners, but we need to find ways to increase our habitual activity levels to prevent processes that drive aging and aging-related diseases.