Assuming the friends mother has type 2 diabetes, there are many aspects in your day to day life that he can take to lower his risk of getting type 2 diabetes. Exercising regularly and eating a healthy balanced diet is key to preventing this disease. He can reduce the amount of fat in his diet, especially saturated and trans fats, and eat more nutritious fruits, vegetables and high fiber foods. Moderate physical activity (I.e. going for a run) 2-4 days of the week accompanied with a healthy diet can help manage weight, reduce blood glucose levels and can also improve blood pressure and cholesterol. The big idea behind these daily changes is to manage his weight. Excess body fat, particularly if stored around the abdomen, can increase the body’s resistance to the hormone insulin which is responsible for the absorption of glucose from the blood into the bodily tissues. Keeping up these habits will drastically reduce the risk of him getting type 2 diabetes.