Metformin is a diabetes drug also sold as Glucophage. Because it helps to regulate blood sugar, it's been shown to help diabetes patients also lose weight. Now, it's increasingly popular as a weight loss aid on its own.
Metformin was first developed in the 1920s, but it was not until later in the 20th century that it became extremely popular as a diabetes drug. It causes few side effects, and by regulating blood sugar, also helps to control hunger levels. It is also used for patients with Polycystic Ovary Syndrome (PCOS).
When you eat high-carbohydrate foods, the liver raises your blood sugar to compensate. In turn, your pancreas must produce insulin to deal with the extra sugar. However, insulin creates feelings of hunger. Metformin helps control the initial blood sugar spike from the liver, thus lessening those sudden hunger pangs.
While preventing the side effects of diabetes, Metformin also helps lower blood sugar. It is only effective, however, if one avoids eating foods that create a rapid insulin spike. A diet based around moderate carbohydrate foods--whole grains, lean meats, fresh produce and dairy--combined with Metformin will usually lead to steady weight loss in diabetics.
PCOS, or Polycystic Ovary Syndrome, is a common cause of obesity in women. The disease is thought to be linked to insulin resistance. As with diabetics, Metformin can help patients with PCOS better regulate their blood sugar levels. This in turn contributes to weight loss.
Certain doctors now prescribe Metformin off-label to patients without either diabetes or PCOS. It must be taken under a doctor's supervision, as an overdose is possible. However, one common dosage is about 500 mg, three times a day, before eating.