"My little brother is 6 and is underweight, and doesn't like to eat almost ANYTHING, EVER. What can I do to help get his weight up? Is it normal for kids to get thin because they're so picky?"
You are raising an interesting question that is exceptionally pertinent in the United States, where so many of us are overweight. As a physician, and a parent of young children, it can be frustrating to deal with the extremely picky food choices of young children. There is a temptation to turn to the fatty, sweet, or salty foods that all children love to eat. This temptation is strengthened by the observation that some children seem to eat almost nothing. In general, giving high fat, high sugar, or high salt-content foods is not an appropriate course of action. Rather, providing many options, repeatedly, will allow children to make healthy choices and develop an adequate diet that does not revolve around a few choice "junk food" items. While good health habits should be encouraged, eating for the sake of eating--even if it means junk food--should not be encouraged. Over time, healthy options will prevail when presented appropriately. When you mention that your brother is underweight, it does raise the question of malnutrition. If you believe that your brother is not developing appropriately, in height, weight, or other measurements, you should seek the help of a physician or dietician. There are reasons that could be contributing to this that are more negative than just picky eating. Your brother should still be having an annual physical exam with his pediatrician, which would be an excellent option to compare his growth and discuss these concerns.
This answer is for general informational purposes only and is not a substitute for professional medical advice.
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