Regular Exercise Reduces Dementia Risk By 30% Or More

A person cyclingA recent study has found that just fifteen minutes of exercise, three days a week may be enough to reduce an individuals risk of developing Alzheimer’s disease and other dementias by more than 30%.

The study, published in the journal Annals of Internal Medicine in January 2006, analyzed 1,740 people over the age of 65 who were initially free of dementia. The participants were followed for an average of 6.3 years during which 107 people (6.1%) developed Alzheimer’s disease and a further 51 people (2.9%) developed other forms of dementia.

The researchers found that those who were physically active were much less likely to develop dementia than those who were less active. Those who exercised 3 or more times a week were 32% less likely to develop dementia and were 31% less likely to develop Alzheimer’s disease. Exercise was defined as performing a physical activity such as aerobics, swimming, hiking, walking, or biking for at least 15 minutes at a time.

The research backs up other studies that have found physically active people tend to develop Alzheimer’s disease later in life than sedentary individuals. It is believed that exercise improves cognitive function, blood flow in the brain, and may prevent brain tissue loss in the hippocampus which is the part of the brain that affects emotions and memory. The hippocampus is one of the first parts of the brain affected by Alzheimer’s disease.

Studies have also shown that mice who are more active throughout their lifetimes exhibit improved learning and are less likely to develop beta-amyloid plaques, the precursor to Alzheimer’s disease, in later life.

According to lead researcher Dr Eric B. Larson who is the executive director of the Group Health Center for Health Studies in Seattle, Washington, it is never too late to begin exercise and enjoying the health benefits associated with it. Most studies have found that maintaining some form of physical activity in later life allows older people to keep their independence and enjoy a good quality of life for longer than would otherwise be the case.