Chubby kids are most likely to eat crisps and, in South African terms, "slap tjips", say researchers who checked food choices and weights of more than 15000 children over a period of six years. Foods eaten regularly by overweight kids were margarine, butter, full-cream milk, sugary drinks, desserts, processed meats, sweets, and fish and chicken in batter.Duke University Associate Professor of Global Health Eric Finkelstein examined the Avon Longitudinal Study of Parents and Children, of 15444 children born in 1991 and 1992 in England to see what foods affected weight gain.He said: "Potato chips are one of the foods most influential in obesity in young people."The study also found that sugary drinks seem to be more "obesity-promoting" than calories from solid foods. This could be because they are less filling than food and therefore easier to consume in greater quantities.Plain fish and chicken were not associated with weight gain and neither were mashed potatoes.The only food associated with weight loss was fibre. Fibre is found in fruits, vegetables and porridge such as oats.Finkelstein said his findings supported government policies taxing sugary foods, designed to make children eat more healthy food. A debate on taxing sugary drinks has dominated headlines in England since celebrity chef Jamie Oliver called for it.In South Africa, the Department of Health has proposed banning the sale of sodas and junk food in school tuckshops but the draft legislation has yet to become law.Vitality Institute's Derek Yach warned against vilifying certain foods. "The excellent study is weak in one respect - total calorie intake is not provided," he said."This is critical since the total intake of all sugars, fats and protein is the most important determinant of weight gain."Yach said that too many people worried about fat or sugar content of individual foods, but didn't take into account the entire diet."Most evidence still shows that these effects [of junk foods] are quite small compared to total intake."But Yach said the study was an example of how health research should be conducted."This is a rare excellent example of how to undertake studies - tracking over time rather than just reporting a snapshot in time."Dietician Lila Bruk, spokeswoman for the Association of Dietetics of SA, said the study's results "came as no surprise".She cautioned against cutting out all treats and urged parents to allow children occasional unhealthy food. She said taxing sugary food merely treated the symptom, not the problem."Knowledge is power. Children must be educated about eating in a healthy way," she said, urging parents to set an example by eating healthily in front of children...