Testosterone is essential for muscle growth, energy levels, mood and a healthy sex drive. Symptoms that your testosterone may be lower than it should be include muscle and strength loss, depression, erectile dysfunction and increased body fat. While weight loss can be helpful to improve testosterone levels, a new study has found that following a low-fat diet isn’t a great idea for healthy levels. The latest review of over 3,100 men found that a low-fat diet can significantly impact total testosterone levels. Previous research has also shown that men whose diets are rich in healthy fats have significantly higher testosterone levels than those whose diets were lacking. So make sure you’re getting plenty of fats from sources like fish, nuts, seeds, olive oil and avocado.