A social media trend encouraging women to double their protein intake could be putting them at risk of a range of cancers, one of Britain’s top diet experts has warned.

Increasing protein levels has been touted as a way to build muscle and protect against mid-life diseases such as osteoporosis.

In recent years, the number of supermarket products with ‘added protein’ has surged.

According to market research firm Mintel, the number of food and drink launches claiming to be high-protein nearly doubled between 2016 and 2020.

At the same time, social media is awash with influencers advising viewers on how to boost their protein intake – with menopausal women, who are prone to muscle loss, often targeted.

But claims that women need to eat significantly more protein during menopause are not only misleading, they could be harmful, warns nutritionist Dr Federica Amati. 

‘Going through the menopause puts women at higher risk of developing osteoporosis and makes it harder to gain and maintain muscle mass,’ says Dr Amati, one of the scientists behind the popular diet app ZOE. ‘But simply increasing your protein intake won’t address this.

But claims that women need to eat significantly more protein during menopause are not only misleading, they could be harmful, warns nutritionist Dr Federica Amati

‘Research shows that high intakes of animal protein in mid-life are associated with cancer. For most women, eating more and more protein is not the answer to staying healthy after menopause.’

UK guidelines recommend adults consume about 0.75g of protein per kilogram of body weight. For the average 72kg woman, that equates to approximately 54g a day.

Experts agree this is relatively easy to meet: a typical 150g chicken breast contains around 36g of protein, an egg about 6g, a 170–200g serving of Greek yogurt up to 20g, and a portion of kidney beans between 7g and 10g.

Yet some influencers recommend as much as 150g a day to ‘help prevent’ bone fractures and muscle decline in later life.

In one Instagram post, an American doctor with 1.3 million followers outlines a daily meal plan that includes egg whites, protein shakes, beef sticks and large servings of meat – totalling more than 140g of protein. And in a TikTok clip viewed more than 430,000 times a UK-based influencer boasts of eating 130g of protein daily.

‘As a personal trainer and a woman navigating perimenopause, I base my meals around some form of protein,’ her caption reads. ‘Our bodies don’t process and metabolise protein the same way as they did in our 20s and 30s, so we need to eat more of it.’ She adds: ‘If I reach 150g, I’m really pleased with myself.’

UK guidelines recommend adults consume about 0.75g of protein per kilogram of body weight. For the average 72kg woman, that equates to approximately 54g a day

But Dr Amati says this approach is misguided. ‘Our protein needs do change over time – but the highest requirement is during infancy and childhood, not menopause.

‘As we age, we produce less growth hormone, so simply eating more protein doesn’t prevent muscle loss. In fact, studies suggest that higher protein intake after the age of 50 can raise the risk of cancer.’

A 2014 study from the University of Southern California involving more than 6,000 adults over 50 found that a high-protein diet – where protein accounted for roughly 20 per cent of total calories – was linked to increased risks of cancer, diabetes and mortality.

Adults with the highest protein intake were four times more likely to die of cancer compared with those on a low-protein diet.

Other research suggests that tumours, including melanoma and breast cancer, may grow faster if a patient is on a high-protein diet.

This, Dr Amati explains, is due to overstimulation of a key cellular pathway responsible for growth.

‘Cancer is the uncontrolled proliferation of cells – so overactivating this pathway increases the risk,’ she adds.

‘Cancer is the uncontrolledproliferation of cells – so overactivating this pathway increases the risk,’ she adds.

Protein from animal sources carries additional risks, she warns.

‘Up to 80 per cent of the protein we eat in the UK comes from animals. But research from Denmark shows that animal protein is richer in certain amino acids that promote fat cell growth and produce compounds linked to heart disease. These amino acids have also been shown to damage cells and tissues, and are linked to neurodegenerative diseases and cancer.’

However, cutting back too far is not advised either.

Dr Amati says middle-aged women should aim for 1.2g to 1.4g of protein per kg of body weight – more than the NHS guidance, but still easily achievable.

She also encourages shifting towards plant-based protein sources, which help boost fibre intake. These include beans, peas, nuts, seeds and oats.