No
We are told to stick to a diet of mostly alkaline foods, as acidic foods create a toxic environment within the body and encourage the development of cancer.
But this nutritional advice has no scientific backing. "There are many beliefs about the connection between body pH and cancer," says Dr Victor Hsue Chan-chee, president of the Hong Kong Association of Community Oncologists.
"One of these is that eating too many acidic foods can cause the blood to become acidic, raising your risk of cancer, and that the solution is to consume more alkaline foods like green vegetables and fruits, particularly lemons. But this is nonsense," he adds.
Dr Lynette Ngo, a specialist in medical oncology and consultant at Raffles Cancer Centre in Singapore, agrees. "The pH level measures how acid or alkaline a substance is. A pH of 0 is extremely acidic, while a pH of 14 is extremely alkaline," she says. "A pH of 7 is neutral. Human blood is slightly alkaline, with a pH of between 7.35 and 7.45. The stomach is very acidic, with a pH of 3.5 or below for the digestion of food to take place.