Chips pose greater health risks than other potato forms: study

An international team led by a Harvard University public health expert has found a shocking link between consuming chips regularly and the risk of developing type 2 diabetes.

Seyed Mohammad Mousavi examined the link between potato consumption and the disease, analysing food questionnaires from 205,000 US health professionals collected every four years between 1984 and 2021, The Guardian reported.

The study, published in the British Medical Journal, found that consuming chips three times a week was associated with a 20% higher risk of developing type 2 diabetes. 

Eating them five times a week increased the risk by 27%. In contrast, having baked, boiled or mashed potatoes with the same frequency raised the risk by only 5%.

Researchers stressed that potatoes themselves do not pose a direct health threat, but frying them to make chips — often with added fat, salt and large portion sizes — is linked to a greater likelihood of a diabetes diagnosis.

"The high starch content of potatoes, leading to a high glycaemic index and load, combined with possible loss of nutrients and possible health risks resulting from various cooking methods, could contribute to adverse health outcomes," the study noted.

The findings also showed that replacing potatoes with whole grains lowered the risk of diabetes by 8%, while substituting chips with grains reduced it by 19%. However, swapping potatoes for white rice increased the risk.

Dr Kawther Hashem, a lecturer in public health nutrition at Queen Mary University of London, said: "Potatoes can be part of a healthy diet, but it's how we prepare them that makes the difference. Boiled, baked, or mashed potatoes are naturally low in fat and a source of fibre, vitamin C and potassium.

"But when we deep fry them into chips or French fries, especially in large portions and with added salt, they become less healthy with their high-fat, salt and calorie content that's much more likely to contribute to weight gain and increase the risk of type 2 diabetes."

Globally, potatoes are the third most commonly consumed food crop after rice and wheat. In the UK, nine out of 10 of the estimated 5.8 million people with diabetes have the type 2 form, which is closely linked to lifestyle and diet.

The researchers emphasised that their findings were observational and did not prove a direct cause-and-effect relationship. The Food Standards Agency and the Department of Health and Social Care declined to comment.