Prevention of diabetes mellitus type 2

Prevention of diabetes mellitus type 2 can be achieved with both lifestyle changes and medication use; onset of type 2 diabetes can often be delayed through proper nutrition and regular exercise.

A 2005 report concluded that "there is evidence that combined diet and exercise, as well as drug therapy (metformin, acarbose), may be effective at preventing progression to diabetes in IGT (Impaired Glucose Tolerance) subjects".

Lifestyle
Increasing physical activity may be helpful in preventing type 2 diabetes, particularly if undertaken soon after a carbohydrate rich meal that increases blood sugar levels. The American Diabetes Association (ADA) recommends maintaining a healthy weight, getting at least 2½ hours of exercise per week (several brisk sustained walks appear sufficient), having a modest fat intake (around 30% of energy supply should come from fat), and eating sufficient fiber (e.g., from whole grains).

Foods with low glycemic index rich in fiber and other important nutrients are recommended notwithstanding limited evidence.

Study group participants whose "physical activity level and dietary, smoking, and alcohol habits were all in the low-risk group had an 82% lower incidence of diabetes".

Various sources suggest an influence of dietary fat types. Positive effects of unsaturated fats have been asserted on theoretical grounds and observed in animal feeding studies. Hydrogenated fats are universally considered harmful mainly because of well known effect on cardiovascular risk factors.

High levels of dietary trans-palmitoleic acid (a fatty acid naturally occurring in milk and other dairy products) were found strongly correlated with reduced risk of type 2 diabetes and reduced cardiovascular risk markers. Overall milk consumption may have a beneficial effect.

There are numerous studies which suggest connections between some aspects of type 2 diabetes with ingestion of certain foods or with some drugs. Breastfeeding may also be associated with the prevention of type 2 diabetes in mothers.

Medications
Some studies have shown delayed progression to diabetes in predisposed patients through prophylactic use of metformin, rosiglitazone, or valsartan.

Lifestyle interventions are however more effective than metformin at preventing diabetes regardless of weightloss.

Many other medications are well known to modify risk of diabetes 2 although in most cases they are prescribed for reasons unrelated to diabetes 2. In patients on hydroxychloroquine for rheumatoid arthritis, incidence of diabetes was reduced by 77% though causal mechanisms are unclear. Dopamine receptor agonists are also known to improve glycemic control, reduce insulin resistance and help controlling body weight.