If you're overweight, eating a lot more protein — especially from whey — for a month won't help your body use insulin better unless you're also losing weight.

If you're overweight or obese and eat the same number of calories, boosting protein or saturated fat from dairy for a month doesn't seem to hurt your blood sugar control or cholesterol levels.

Taking extra protein shakes after losing weight doesn’t help you keep the weight off any better than eating the normal amount of protein in your daily diet.

If you're overweight and eat a lot of protein—especially from whey—for a month, your blood sugar might go up a bit, but only if you're also eating very little saturated fat. If you eat more saturated fat, that same high-protein diet doesn't seem to affect your blood sugar.

When healthy young adults consume a high-protein meal with 25% of energy from whey protein, their bodies produce more active GLP-1 and insulin after eating than when they consume the same amount of protein from casein or soy, but they do not feel less hungry or eat less afterward.

Among overweight or obese adults on a 4-week calorie-restricted diet, consuming 30% of daily calories from protein results in 4.6 kg more fat loss than a low-glycemic-index diet, with no loss of muscle mass.