 [ Symptoms ] my son is 16 and he is convinces that cabohydrates from grains will damage his joint health is this true [ Disease ] i think it is good that your son is concerned about his diet and seeking to become knowledgeable on the subject that is a trait to encourage however i think he is confusing several different issues here let me see if i can briefly untangle this for you first i know of no studies that support a direct connection between grain consumption in general and joint disease or damage second there may be some connection between gluten which is a protein found in wheat grains and autoimmune diseases such as rheumatoid arthritis which obviously affects the joints again i do not know of any studies that confirm this but i do believe the issue is being studied right now third people who have rheumatoid arthritis may be at higher risk of also being diagnosed with celiac disease which is an inability to digest gluten so i think your son is confusing carbohydrates from grains with gluten  and the two terms are not interchangeable rice is a grain that does not contain gluten for example importantly your son needs to know that at his age especially he needs to eat a well balanced diet that includes plenty of complex carbohydrates    including grains if he is dead set against eating gluten i would suggest he switch to brown rice though recently brown rice was found to contain high levels of arsenic so he needs to monitor his consumption of this too unless your son suffers from severe digestive problems after eating gluten products like whole grain breads white bread breakfast cereals etc  he probably is at very low risk of developing any joint problems from eating whole grains if after this explanation your son is still concerned i would suggest he visit his health care provider he or she can work with your son to develop an eating plan that makes everyone happy    and keeps your son healthy best to you