If a daily fitness walk could be put in a pill, it would be one of the most popular prescriptions in the world. It has so many health benefits. Walking can reduce the risk of many diseases — from heart attack and stroke to hip fracture and glaucoma. These may sound like claims on a bottle of snake oil, but they're backed by major research. Walking requires no prescription, the risk of side effects is very low, and the benefits are numerous:

Managing your weight. Combined with healthy eating, physical activity is key to any plan for long-lasting weight control. Keeping your weight within healthy limits can lower your risks of type 2 diabetes, heart disease, stroke, cancer, sleep apnea, and osteoarthritis.

Controlling your blood pressure. Physical activity strengthens the heart so it can pump more blood with less effort and with less pressure on the arteries. Staying fit is just as effective as some medications in keeping down blood pressure levels.

Decreasing your risk of heart attack. Exercise such as brisk walking for three hours a week — or just half an hour a day — is associated with a 30% to 40% lower risk of heart disease in women. (Based on the 20-year Nurses' Health Study of 72,000 female nurses.)

Boosting "good" cholesterol – the level of high-density lipoproteins (HDL). Physical activity helps reduce low-density lipoproteins (LDL or "bad" cholesterol) in the blood, which can cause plaque buildup along the artery walls — a major cause of heart attacks.