A perfect storm is brewing, nutritionally—and it could easily sweep you away. One of every three Americans has some form of prediabetes (often undiagnosed), and 25 million have full-blown type 2 diabetes. Being overweight or obese are the primary risk factors, although family history, inactivity, race, and age also can contribute. Eating whole foods and avoiding junk foods and sugary drinks can help. Ditto for muscle-building resistance exercises.

People with prediabetes or type 2 diabetes often lack adequate levels of many vitamins and minerals, a consequence of poor eating habits. Supplements correct these deficiencies and help restore normal metabolic activity. They also complement a healthy diet and exercise. And there’s a bonus: When you control your blood sugar, hunger jags decrease and weight loss becomes easier. Lower doses of these nutrients can help with prediabetes, higher doses with type 2 diabetes. If you take more than one of them, opt for lower doses.

Silymarin. Three studies have proven this antioxidant extract of milk thistle (Silybum marianum) can lower fasting and post-meal blood sugar levels and reduce excess insulin. A longer-term indicator—HbA1c (glycated hemoglobin) levels, which provide an average blood sugar level over six weeks—declined significantly, too. In one of the studies, people taking silymarin also lost about 8 percent of their body weight.

Dose: 200 mg one to three times daily.

Chromium. This mineral activates insulin, a hormone that helps the body burn blood sugar instead of storing it as fat. A study of 180 people with type 2 diabetes found that chromium supplements significantly improved blood sugar and insulin levels after just four months. And in a recent three-month study, chromium supplements lowered fasting blood sugar levels
by almost half in 40 people newly diagnosed with type 2 diabetes.

Dose: 500 mcg once or twice daily.

Resveratrol. Best know for its antiaging benefits, this antioxidant boosts the activity of SIRT1, a gene known to slow the aging process; it also helps regulate blood sugar. A study published this year in British Journal of Nutritionreported resveratrol supplements improved blood sugar and insulin levels in men with type 2 diabetes.

Dose: 250 mg daily or 100 mg with each meal.

Alpha-lipoic acid (ALA). Doctors in Germany use this antioxidant to treat nerve numbness and pain in people with diabetes. It works in part by improving insulin function. A recent eight-week study found that ALA reduced fasting blood sugar, post-meal blood sugar, and insulin levels in people with type 2 diabetes. ALA might also aid with weight loss, according to a new study in The American Journal of Medicine.

Dose: 100–200 mg with each meal.

Vitamin D. A study of 5,200 people in Australia found that high vitamin D levels lowered type 2 diabetes risk by 24 percent or more. Adding calcium might enhance the benefits. One study found that the vitamin D–calcium combination maintained normal blood sugar levels over three years, while blood sugar levels increased in people taking placebos.

Dose: 1,000 IU vitamin D and 500 mg calcium daily.

Magnesium. Three of every four people with type 2 diabetes lack adequate magnesium due to poor diets. In a recent study, prediabetic patients took magnesium supplements daily for six months; at the end, they had lower fasting blood sugar levels and better insulin function.

Dose: 200 mg twice daily.