Chris Hemsworth's high-protein meal plan that can 'help reduce the risk of Alzheimer's'

After receiving a "shocking" warning that he could have an increased risk of Alzheimer’s disease, Chris Hemsworth has changed several aspects of his life, including his diet and exercise routines.

The Thor star, 39, discovered that his DNA contains two copies of the gene APOE4, which has been linked to a higher risk of Alzheimer’s, while filming the National Geographic docuseries Limitless.

In a new interview with News.com.au, Hemsworth’s private chef Sergio Perera revealed how the actor eats on a day-to-day basis, involving plenty of protein and olive oil.

Sergio said: "Obviously the guy is a big boy. He requires a lot of protein for the body he has. When it comes to building muscle he just keeps it very clean with a lot of barbecuing – like meats and vegetables – and keeping it Mediterranean which involves a lot of olive oil.

Read more: Chris Hemsworth details major lifestyle changes since learning of Alzheimer’s risk (Evening Standard, 2-min read)

"One thing I did religiously with him was, every single day, he would have one very large, hearty salad that consisted of raw and cooked vegetables, fermented products, nuts, seeds and a lot of good fats with a piece of steak or a big piece of fish," Sergio said.

According to studies, Hemsworth’s high-protein diet could do more than keep him fit and lean.

Does eating a high protein diet protect you from Alzheimer’s and dementia?

Several studies on this topic have shown a positive link between a high intake of protein and lower risk of Alzheimer’s disease, although scientists have called for further research to explore this link.

A study published by Harvard in January 2022 suggested that eating protein is associated with lower odds of developing cognitive decline later in life. Researchers found that for every 5% of calories that come from an animal protein, there was an 11% lower risk for developing dementia.

However, the figures are even more impressive when it comes to plant protein. The study found that for every 5% of calories that came from plant protein, there was a 26% lower risk for developing dementia.

"Beans and legumes had the strongest protective association. Peas and lima beans in particular were associated with a 28% lower risk of cognitive decline for every additional three servings per week," Dr Tian-Shin Yeh, lead author and postdoctoral research fellow at the Harvard TH Chan School of Public Health, said.

Read more: Eating enough fruit and veg lowers risk of memory loss, says a new study (Yahoo Life UK, 2-min read)

The results echo that of a 2018 study by Edith Cowan University, which found that a diet high in protein-rich foods, such as meat and legumes, has the potential to reduce the risk of developing Alzheimer’s disease.

Researchers from ECU’s School of Medicinal and Health Sciences found that study participants with higher levels of protein in their diet were less likely to have high levels of amyloid beta, an amino acid that is known as a precursor to Alzheimer’s.

Amyloid beta denotes peptides of 36–43 amino acids, which are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease.

But the study found that, among participants with the highest consumption of protein at around 118g per day, were 12 times less likely to have high levels of amyloid beta than those who ate the least amount of protein at just 54g per day.

Dr Binosha Fernando, joint lead researcher, said: "The research clearly demonstrates that the more protein eaten, the lower the chances someone has of having a high amyloid beta burden on the brain, which corresponds to a lower risk of developing Alzheimer’s disease."

However, scientists don’t know why high levels of protein may result in lower levels of amyloid beta burden. Dr Fernando suggested that previous studies have shown a high protein diet is associated with lower blood pressure, whilst high blood pressure is a risk factor for both Alzheimer’s disease and cardiovascular disease.

Read more: Alzheimer's signs and symptoms as Ken Livingstone 'living with the disease' (Yahoo Life UK, 5-min read)

Should I eat a high protein diet?

It is important to eat a healthy and balanced diet, with plenty of protein as well as vegetables and fruits. While eating a high protein diet has been shown to lower the risk of cognitive decline, it is not a definitive benefit and may affect different people according to their lifestyle factors, genetics, and other external factors.

You can also eat too much protein, depending on how your body works. Having excess protein can put pressure on the kidneys, and excess animal protein has been linked to kidney stones and even kidney disease.

It has also been suggested that high protein intake could be bad for bone health, as it is thought to cause demineralisation because of increased urinary calcium excretion.

According to the British Dietetic Association, Britons overconsume protein across all age groups and genders, with 19 to 74-year-olds exceeding recommendations by 38-57% and over 75-year-olds consuming 22% and 33% above recommendations for women and men respectively.

Nutrition states that the recommended nutrient intake is 0.75g of protein per kilogram body weight per day for adults. It is recommended that men aged between 19 to 50 years of age consume 55.5g of protein per day, and women eat 45g per day. This should be a mix of animal and plant proteins.

Watch: Chris Hemsworth has changed his lifestyle after learning he is at increased risk of Alzheimer's disease