The high protein diet and our microbiome

Biome Basics

Our gut contains trillions of bacteria that have a weight of over 1kg!

Bacteria perform different functions for us – help to break down foods, manufacture vitamins, amino acids, calm our immune system, influence our mood and may even affect our ability to cope with stress. Traditionally our gut microbiome was much more diverse before the development of antibiotics as well as before the development of specific types of food additives.

It’s a partnership

Fibre passes into your large bowel and feeds your gut bacteria, then good bacteria such as Bifidobacterium create short chain fatty acid compounds such as butyrate. Butyrate is food for your endothelial cells that line your gut and helps maintain the barrier between the endothelial cells and the contents of the gut. Butyrate helps the body make more T regulatory cells that reduce inflammation and has also been associated with a reduced risk of bowel cancer.

Western diets

Westerners typically eat less than the recommended amount of fibre and are high in protein. Having higher levels of protein in the diet has been shown to increase diversity, while perhaps not in a favourable way. Very high animal protein diets have been shown to reduce the beneficial species Bifidobacterium and increase the pathogenic Clostridia. A large participant prospective study found that high total protein intake, especially animal protein, is associated with a significantly increased risk of irritable bowel disease. Additionally, bacteria that thrive when the host eats red meat can create higher levels of trimethylamine-N-oxide (TMAO), a pro-atherogenic compound that increases the risk of cardiovascular disease.

Artificial sugars, processed meats and emulsifiers have all been implicated with detrimental effects on the gut microbiome. Recent evidence suggests that consumption of all types of artificial sweeteners is actually more likely to induce glucose intolerance than consumption of pure glucose and sucrose. Artificial sweeteners have been found to unfavourably change our gut microbiome to promote weight gain. Processed meats have been found to reduce gut diversity and emulsifiers (contained in most breads) have been shown to decrease the protective barrier between our endothelial cells and the contents of the bowel in animal studies.

What do we eat?

The Heart foundation recommends 25-30g fibre a day. Fruit, vegetables, legumes, wholeg