A third of Britains children, and two-thirds of adults, are now overweight or obese  but halving childrens intake of sugar-sweetened drinks could arrest or even reverse current trends.

London - “Healthy fizzy drinks” sounds like a contradiction in terms, but research is now unveiling possible benefits from these beverages.

Earlier this month, scientists discovered that cola is highly effective at dealing with a blocked stomach, known as a gastric phytobezoar. This causes nausea, vomiting, diarrhoea and can occur as a complication of gastric surgery. New research from the University of Athens suggests cola acts like stomach acid on it.

Here are the ways fizzy drinks can help with more everyday ailments...

CRAMP: A glass of tonic water before going to bed may help prevent cramp, according to Dr Mike Dixon, visiting professor of integrated health and care at the University of Westminster, London. Tonic water contains small amounts of naturally occurring quinine (the ingredient that gives it its bitter taste), which can prevent muscles going into spasm.

CONSTIPATION: Italian researchers found that sparkling water may ease constipation and heartburn. One theory is the combined effect of the carbon dioxide bubbles and the minerals calcium and magnesium helps food move through the digestive tract and reduces the production of stomach acid. Magnesium has a mild laxative effect while calcium may neutralise the effects of stomach acid in heartburn. Carbon dioxide gas may push against the walls of the intestine, causing contractions that help relieve constipation.

LACK OF CONCENTRATION: Researchers at the University of Georgia found gargling with lemonade may help concentrate the mind. The team believes that glucose stimulates the sugar sensors on the tongue which, in turn, signals the motivational centres of the brain. These signals tell your body to pay attention. It might not be so good forteeth, though.

DIFFICULTY SWALLOWING: A fizzy drink can help shift food that may feel stuck in the gullet, says Dr Peter Fairclough, consultant gastroenterologist at London Digestive Health. The bubbles of carbon dioxide generate pressure, which helps push food down the gullet.

HIGH CHOLESTEROL: Fizzy water may help lower “bad” LDL cholesterol. In a study in the Journal of Nutrition, volunteers were asked to drink a litre of either sparkling or still each day for two months, followed by two months on the other water. Compared with the still mineral water, sparkling water was linked to a significant reduction in the LDL, as a rise in “good” HDL cholesterol occurred. One theory is that change is triggered by the drink’s high sodium content — studies show low sodium diets may increase cholesterol.

DIARRHOEA: Drink flat, full-sugar lemonade to help prevent dehydration. Dehydration can lead to loss of sugar and salt. Flat lemonade is easier to drink in larger amounts than fizzy, while the sugar and salt increases water absorption, says Dr Adam Carey, director of nutrition at Core Performance. For optimum concentrations of sugar and salt, mix half a glass of the lemonade with half a glass of water. - Daily Mail