Time to tackle the macronutrients, protein, carbohydrates and fat. They are called macronutrients because they are required in larger quantities. The protein we eat, or the amino acids they contain, are the building blocks of proteins in our body. Proteins are required for immune function, enzymes for cellular processes, certain hormones, cell structure and of course repair and remodeling of muscle. There are 9 amino acids that are essential (EAA), meaning we must get them in our diet. Of the EAA leucine seems to be the most important for muscle building.

How much do we need? The requirement for an adult is 0.8g/kg (0.4 g/lb) body weight. It is based on a level that achieved nitrogen balance and did not take into consideration activity. For individuals carrying extra weight, the body weight to use for the calculation should be based on adjusted weight. Check out the Examine.Com protein needs calculator. FYI, Examine.com is a great resource for diet/supplement information. It is very well referenced.

Athletes need more protein, from 1.2-1.7 g/kg (0.6-0.7 grams/lb) with endurance athletes needing the lower end and strength athletes needing the higher end of that range. Athletes consuming protein within a couple of hours after resistance training can help maximize “muscle building”. That protein can be real food. And the window is wider than we think.

We also need more protein as we age primarily because we are less efficient at building muscle. But if we have been physically active our whole lives the resistance to building muscle is minimized (Moore D, Sports Med 2021). And of course both endurance- and resistance-type exercises help us maintain muscle.

How much at a time? For the best chance at using protein for muscle protein synthesis a common recommendation recently is to consume 30 grams a meal for two meals, with breakfast being the more important meal. But remember eating protein alone does not create new muscle mass there must be a stimulus from exercise. Then 15-25grams at other meals/snack helps with satiety, protein synthesis and evens out insulin spikes.

What does 25 g look like?

This brings us to animal vs. plant protein. You can see that to get 25g of protein from certain foods requires a large quantity and a lot of calories. Animal proteins are “complete” meaning they contain all 9 EAAs. The plant foods that are considered a complete protein are limited. Soy foods (example: tofu, tempeh) are complete proteins. Quinoa, hemp, chia are also complete proteins but the volume needed to get 25 grams is pretty high. But they are great additions to foods to boost protein.

Plant protein food sources that are incomplete protein sources can be combined to provide all EAA. For example, a peanut butter sandwich. Does this need to be in the same meal? Probably not. Ezekiel bread contains a combination of whole foods that ends up containing all EAA.

The decision to include animal foods in your diet is an individual choice. They can certainly be part of a “healthy” diet. Likewise, you can have a “healthy” diet that does not contain animal products. But remember there are plenty of ultraprocessed foods that are vegetarian. They do not contribute to health.