Eating fewer carbs and more fat helps your body make more testosterone.

When overweight men eat a very low calorie diet for 12 weeks, their testosterone levels go up a lot, which can help improve their health.

Eating only animal foods with lots of fat might keep a man's testosterone levels high, even if he's eating less or is already lean.

The amount of fat consumed in the diet is associated with changes in testosterone levels in the blood, with higher intake between 50 and 150 grams per day linked to higher levels.

Could the stuff added to processed foods affect men's testosterone levels?

Among middle-aged men who lift weights and eat fewer calories, levels of testosterone rise and insulin levels fall, whether they follow a ketogenic diet or a different type of low-calorie diet.