You're probably aware that eating and drinking added sugar increases the risk of developing diabetes. But did you know that including certain foods in your diet might actually help prevent that condition? Here are five foods that studies have linked to a lower risk of type 2 diabetes (which accounts for 90 percent of diabetes cases worldwide), or to increased blood-sugar control in people in the early stages of the disease. Note that all but one of the studies are observational, meaning they can't prove causality; they can only show an association. But each of these foods has also been linked to other health benefits, so consider the findings one more reason to include them in your diet.
Good news for those of us who enjoy starting the day with yogurt: According to a study of 4,000 people ages 40 and older published in Diabetologia, eating this most cultured of foods may reduce the risk of developing type 2 diabetes. Specifically, the study indicated that people who ate about 20 ounces of yogurt per week were almost 30 percent less likely to develop diabetes than non-yogurt eaters. For an extra shot of protein, choose Greek yogurt.
Fruit (but not Fruit Juice)
Fruit sometimes gets a bad rap because of its naturally occurring sugars, but that's no reason to avoid it. In fact, certain fruits, including blueberries, grapes, and apples, have been linked to a lower chance of developing diabetes. In a study of 187,000 nurses and other health professionals, those who ate at least three servings a week of those fruits were up to 26 percent less likely to develop diabetes than people who rarely ate them. In contrast, drinking fruit juice has been found to increase diabetes risk. So stick with whole fruit, which contains fiber and numerous beneficial vitamins, minerals, and phytochemicals.
Numerous studies have found that people who regularly drink coffee—regular or decaf—have a lower risk of type 2 diabetes, though it hasn't been entirely clear why. One possibility is that the polyphenols (a type of antioxidant compound) in coffee may enhance insulin sensitivity and slow the release of glucose into the bloodstream. Another is that compounds in coffee may inhibit the formation of abnormal pancreatic proteins that contribute to diabetes, as proposed by a 2013 Chinese study. Alas, drinking coffee doesn't appear to benefit people who already have diabetes.
Let's hear it for nuts. A 2014 Spanish study in the journal Diabetes Care found that people with prediabetes who ate two ounces of pistachios a day—that's around 80 pistachios—saw improvements in insulin levels, blood sugar, and other factors compared to people in a control group who ate no pistachios. Better yet, other nuts, including walnuts and almonds, are also linked to lower diabetes risk.
Some naturally occurring substances in cinnamon have been shown to help control blood sugar. A 2012 clinical trial in the Journal of the Academy of Nutrition and Dietetics found that cinnamon added to farina cereal appeared to modify the normal increase in blood sugar in obese people, as well as those at a healthy weight. Other studies have not shown this effect. The research is too inconsistent and preliminary for us to recommend cinnamon supplements. (And some cinnamon supplements often contain other ingredients of even more dubious value.) So stick to adding cinnamon to food.
See also: Should You Be Tested for Diabetes?