Experts have rubbished claims made by a businessman that so-called  ‘superfoods’ can prevent cancer.

John Wishart, 58, has owned the shop, Simple ‘n’ Natural, in High Street, Wanstead, for 15 years.

He advocates alkaline 'superfoods', which he stocks alongside other ‘remedies’ and vitamin supplements.

Mr Wishart said: "It’s all about pH levels, and too much acid can cause cancer. Cancer thrives in an acidic environment, so balancing this out is really important.

"Busy people need good food, and there is too much acid in modern diets with people eating foods like potatoes, pasta, oranges and tomatoes.

“Superfoods such as spirulina, chlorella, barley grass and wheatgrass are alkaline, and will dramatically reduce the chances of getting cancer."

But experts at Cancer Research UK said there is no legitimate scientific proof for Mr Wishart’s claims.

Yinka Ebo, senior health information officer at Cancer Research UK, said: “Our body’s level of acidity – the pH – is controlled very tightly and it’s a myth that diet can influence the acidity of our blood or body, or that changes in overall body pH are linked to cancer.

"If a person’s body acidity changed even by a small amount, it would be extremely dangerous. 

“Scientists around the world are looking at the impact of diet on cancer risk and the evidence doesn’t support eating a specific food or nutrient on its own to protect against cancer.

"Decades of research tells us that the best diet for reducing the risk of cancer and for general health is a healthy, balanced one, that is high in fibre, fruit and vegetables, and low in red and processed meat, saturated fat and salt.”

Mr Wishart, originally from Glasgow, and has been a vegetarian for 25 years.