How much protein is enough? If you're working a 9 to 5 desk job that you commute to by car, protein isn't an issue. But for someone who's active in sports and trains regularly, adequate protein is essential for losing fat and building lean muscle. Your safest bet is to get between 0.8 and 1 gram of protein per pound of lean mass.

When calculating that amount, use the weight you think you would look good at, especially if you're 20 or more pounds overweight. For example, if an ideal weight for you would be 170 pounds, multiply that number by 0.8 grams: Your daily protein requirement turns out to be 136 grams, which translates to 27 grams of protein per meal (at five meals per day). That's what you'll get from about one small can of water-packed tuna or four slices of turkey breast deli meat.