Teeth can provide a warning of eating habits that lead to ill health, an expert has claimed.

Teeth can provide a warning of eating habits that lead to ill health, an expert has claimed.

Foods that affect blood sugar levels and may increase the risk of cancer and other chronic diseases first attack the teeth and gums, according to Professor Philippe Hujoel.

Writing in the Journal of Dental Research he said tooth decay and gum disease can signal a need to change diet.

The "bad" foods are high glycaemic (high GI) carbohydrates that break down quickly to release sugar.

As well as being linked to diabetes and liver disease, they also increase sugar levels in the mouth, leading to dental problems.

High-GI foods include sticky cakes, donuts, biscuits and sweets, but also some fruits, as well as starchy potatoes, white rice, bread and pasta.

As well as diabetes, some experts suspect abnormal blood sugar might play a role in disorders ranging from Alzheimer's to pancreatic cancer.

Rates of some of these conditions have been correlated with dental disease.

Prof Hujoel, from the University of Washington in Seattle, said: "There is fascinating evidence that suggests that the higher the glycaemic level of a food, the more it will drop the acidity of dental plaque, and the higher it will raise blood sugar.

"So, possibly, dental decay may really be a marker for the chronic high-glycaemic diets that lead to chronic systemic diseases."