The optimal diet for a healthy gut

Diet quantity and quality have a crucial impact on the gut microbiota composition and function.

Several factors are thought to impact the gut microbiota. We also discussed that one of the most important factors that could influence gut microbiota is diet.

Diet type and the gut

Research shows that many aspects of diet can influence gut microbiota. These include:

• Overall dietary pattern (for example, Western, Traditional, Mediterranean or vegetarian).
• Specific foods consumed (such as grains or vegetables).
• Specific food constituents (for example, fibre, fat or phytochemicals).

Although we are yet to have a clear understanding as to what a healthy gut microbiota should consist of, the common understanding is that a diverse microbiota is a healthy microbiota and that consuming a wide (diverse) range of healthful foods is important in achieving this.

There are many aspects of diet that we know affect the gut microbiota. In particular, foods with a high amount of fibre, such as plant foods – grains, legumes, vegetables, fruit, nuts and seed – support the growth of beneficial bacteria that, in turn, have a beneficial impact on the gut and the overall health, including mental health.

Fermented foods

Another food group that has shown a promising effect on gut health is fermented foods. A variety of fermented foods are consumed around the world such as yoghurt, kefir, tempeh, kimchi, miso and kvass.

Fermentation is a natural process that occurs when bacteria down food components, eg sugar, to produce by-products such as lactic acid. Fermentation is thought to increase the production of beneficial compounds for the body such as short-chain fatty acids.

Fermentation is thought to increase the bioavailability and antioxidant activity of foods largely due to a variety of beneficial metabolites produced in the process, including short-chain fatty acids.

Probiotics and prebiotics

Probiotics or prebiotics are popularly referred to in relation to gut health.

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Food or supplements?

Some probiotics and prebiotics are available in purified supplements. However, consuming these via food sources will also deliver a range of macro-and micronutrients and reduce any possible side effects.

Other foods thought to be beneficial to gut health are, as discussed in Managing inflammation, fish and seafood that are high in Omega-3 fatty acids and foods high in phytochemicals (eg polyphenols and carotenoids) as colourful plant food.