Researchers randomly assigned 38 people who had prediabetes and were obese to one of two diets. Each cut 500 calories a day.1
After six months, 14 people had dropped out. However, blood sugar levels in all of the remaining 12 people on the higher-protein diet—but in only four of the remaining 12 on the higher-carb diet—had fallen into the normal range. What’s more, the higher-protein group had lower hemoglobin A1c (a long-term measure of blood sugar) and lower LDL (“bad”) cholesterol, triglycerides, and some markers of inflammation.
Both groups lost the same amount of weight, but people on the higher-protein diet lost only fat, while those on the higher-carb diet lost both fat and muscle.
What to do: If you have prediabetes, try cutting back on carbs. (That will cut your calories and make protein a higher percentage of your diet.) Although this small study needs to be replicated, it’s worth a try. And you needn’t cut all carbs. You can still enjoy vegetables and fresh fruit, with small servings of grains.
Strength training may also help make prediabetes disappear.
The Resist Diabetes trial enrolled 159 sedentary overweight or obese adults with prediabetes in a strength-training program for three months.2 Twice a week, they did 12 supervised exercises (like leg presses, chest presses, and abdominal crunches) for 8 to 12 repetitions each.
Then each participant was given one of two different levels of encouragement for six months, followed by six more months when they were on their own.
After the 15 months, 30 percent of the participants no longer had prediabetes. It made no difference whether they received more or less encouragement.
Although the volunteers didn’t lose weight, their waistlines did shrink. And those who gained the most muscle were the most likely to reverse their prediabetes.
What to do: If you’re not doing strength training, get started. People lose muscle as they age. Building strength is the best way to stop or reverse that loss, whether or not you have prediabetes.