Ensure that your son eats mainly fresh raw vegetables and fresh raw fruits and less junk. Following the ratio of 60% vegetables of which 50% should be eaten raw, 20% fresh raw fruits, 10% carbohydrates, 10% proteins
. Include nuts and seeds in his diet. It is very important that your son eats a very wide variety of foods and that his meals are varied. In other words there should not be any form of natural foods including seeds and nuts, that exist in your country that your son does not eat. It is your responsibility to see to it that he eats for goods health. All natural foods inclusive of dairy products are good for ones health. Avoid artificial seasoning and use mainly allium vegetables and thyme for the flavoring of meats, steamed vegetables, rice and peas and other foods that you normally season. Have him avoid foods with excess salts such as some salty biscuits and chips that might be on the market.
I've elaborated more on the food ratio at http://answers.yahoo.com/question/index;_ylt=Apb49o0_0NIJJ0bTC.3wGkrty6IX;_ylv=3?qid=20090205075625AAF8aMT&show=7#profile-info-Th1EmKVtaa