Drugs that slow aging are a hot research topic. In a recent study scientists showed that treatment with Metformin, a diabetes type 2 drug, slows aging in monkeys. Animals aged 13 to 16 years (equivalent to 40 to 50 human years) were treated with 20 mg/kg per day for 1200 days. This treatment prevented brain atrophy, and elevated cognitive funtioning in male animals without producing severe side effects compared to a control group. Moreover, aging of other tissues (e.g. the liver) was slowed.