All foods are made up of the three macronutrients: Protein, carbohydrates, and fats. These are the things we need in relatively large quantities to be healthy, hence the term “macro”. They are also sources of energy, with protein and carbohydrates providing 4 kcal of energy per gram and fats 9 kcal per gram (alcohol provides 7 kcal of energy but as it is not a necessity, is not a macronutrient).
For all the hype about fats and carbohydrates, the first thing to get right in any eating plan is the amount of protein in your diet. Protein is necessary to grow and repair muscles, and the more muscles you have, the more calories you burn at rest. Protein is also the most satiating of the macronutrients – it makes you feel full, which makes it easier to eat less and reduces cravings for sweet treats. This is why eating more protein can help with weight loss.
The current guidelines are 0.6g of protein per kilogram of bodyweight per day for a sedentary person. However, endurance athletes need 1.2 to 1.4g/Kg/day to recover properly, and those looking to gain muscle mass need 1.5 to 2.0g/Kg/day1. Many athletes in power sports actually eat far more than this, but research has shown that the ideal amount of protein for maximising strength gains is 1.6g/Kg/day. There is some evidence that protein intakes of 2.3 to 3.0 g/Kg/day may help maintain muscle mass when seriously cutting calories1.
Eating too much protein is not usually harmful to health, as most people just pee out the extra. But it is expensive and can very hard to keep up. If you weigh 100Kg and are looking to gain muscle mass and lose body fat, you’ll be looking at more than 200g of protein per day. That’s over 700g of cooked chicken breast! Of course, we get protein from lots of different foods, including many plant foods. But deciding you need more than that is going to make your life difficult, even with supplements (protein shakes, protein bars, etc.).
Most athletes can meet their protein needs by having protein dense foods at every meal and snack. This could be eggs at breakfast, a tuna or chicken sandwich for lunch, Greek yoghurt with nuts and berries as a snack, and tofu stir fry for dinner. That being said, the convenience of protein shakes can make them the best choice after a hard workout. Optimal nutrition is all about what works for you.
1. Ralf, J. et al. 2017. International Society of Sports Nutrition Position Stand: Protein and Exercise. J Int Soc Sports Nutr.2017; 14: 20. doi: 10.1186/s12970-017-0177-8