in some cases active teenagers are so busy and stressed that they don't get adequate nutrition and calories. it sounds like your grandson's appetite is down and reflux is suspected. it's best to get him to a doctor so he can find out if it's acid reflux another gastro-intestinal issue or something else. for now small frequent (wholesome) meals that aren't fried greasy or spicy and are free of caffeine may improve tolerance and appetite. for more on symptoms of acid reflux see this webmd article <link>
why could my healthy athletic 17 yr. old grandson have lost almost 10 pounds in a month? . his appetite has decreased. he used to be hungry about every two hours after eating like a normal teenager - a lot! he's playing varsity football and has been experiencing what appears to be acid reflux.