Plant Protein vs Animal Protein

First let’s have a look at the differences between plant protein and animal protein and their effects in the body.

If you think about the old school thought process, in terms of, animal protein is complete protein and contains all the essential amino acids, and lots of them, and plant protein
is not complete protein and doesn’t contain all of those essential amino acids. While this old school thought process may be indeed correct, that many plant-based sources of protein are incomplete. It never really asked why this would be the case? It turns out that not having lots of  complete animal proteins and lots of amino acids is actually better for human health. Let me give you some very specific examples.


If you eat animal protein then you get lots of the amino acid leucine. Anyone from the paleo camp or bodybuilders will tell that you need to eat lots of leucine to build big strong muscles. The issue is, lots of leucine in your diet can activate mTOR, which is an enzymatic pathway that leads to increased risk of cancer and accelerated aging process.

Another really problematic constituent part of animal protein is methionine. The science is quite clear here – high amounts of Methionine in the diet feeds cancer cells. So you really don’t want to be eating too much of it.

On the flip side plant protein contains a lot of glutamic acid and glutamic acid is an amino acid that combines with cysteine and glycine to convert into glutathione. Glutamic acid is hardly found in animal protein. The problem with this is, if you don’t have a lot of glutamic acid
in the body then you won’t produce a lot of glutathione which is an antioxidant that protects your cells and DNA from damaged. Glutathione also helps your body absorb amino acids. Glutathione is pivotal for keeping blood pressure down. Which is why those eating high animal protein diets with low amounts of glutamic acid and low amounts of glutathione tend to have higher rates of hypertension. These glutathione – glutamic acid balance is one of the main proponents of why vegans have lower rates of hypertension and subsequent issues.

The thing that vegans need to remember is that an amino acid is an amino acid regardless of whether it’s from an animal or plant-based source. The amount of the amino acids is the damaging factor in the body and it always makes me worried for those vegans who are loading up on protein powders high in leucine, methionine and branched chain amino acids. It may be leucine, methionine in conjunction with the saturated fat and cholesterol from meats that damage the body and not just the amino acid per se. We simply don’t know so I wouldn’t take
that risk. But fundamentally an amino acid is an amino acid regardless of where it comes from so maybe think twice before having that protein powder for breakfast.

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