Protein powders. Protein yoghurt. Protein snack bars. Protein is everywhere. Supermarket shelves and social media are full of messages encouraging us to eat more of this nutrient.

But now, a new review of over 350 studies suggests eating less protein may be linked to healthier ageing, by slowing down the biological process of ageing in cells.

These messages can sometimes feel confusing. How much protein should you eat?

Importantly, most of the evidence in the new review comes from animal studies, not humans. So let’s take a look at what it actually means for you.

First, how much protein do you need?

Protein is a nutrient made up of amino acids, and found in a wide range of foods. It is essential for maintaining muscles, repairing tissues and supporting overall health.

Australian dietary guidelines recommend around 15–25% of our daily energy comes from protein. Good sources include legumes, nuts, fish, eggs, dairy and lean meat.

Data shows most Australians already meet these recommendations.

Read more: What happens if I eat too much protein?

What the new study looked at

The new research brings together evidence from animal and some human studies to better understand how restricting protein (and specific amino acids) influences the biology of ageing.

Overall, the evidence suggests eating less protein changes the way the body uses energy, helps cells remove damaged components, and reduces the build-up of ageing cells. Together, these biological changes are associated........

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