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Glutamine is an amino acid produced in your body. Amino acids are building blocks of protein which are important for regulating cell growth and function. In particular, glutamine helps remove waste, also known as ammonia, from the body. It also helps your immune and digestive system. Within the body, glutamine is stored in your muscles and lungs. Your body generally gets the majority of its glutamine by producing the substance itself and through your daily intake of food. However, when your body is under stress, you suffer an injury, or you have an infection, your body may not be able to produce enough. When this happens, there are two ways to get additional glutamine: through food or supplements. You can get it naturally by supplementing your diet with an increase of glutamine-rich foods. Glutamine is naturally found in high protein foods such as dairy, fish, meat, beans. It can also be found in vegetables like spinach, cabbage, and parsley. Although these foods provide glutamine, they do not provide as much as supplements do. If you cannot get enough glutamine through your food, or if you need additional glutamine because of increased stress on your body, ask your doctor about the supplement. The dosages and type you should take can vary greatly depending on what condition for which you are being treated. Your doctor can tell you whether this form of treatment is worth pursuing and can advise you on what quantity of glutamine to take.  Generally, the dosage of the supplement used is 5g to 10g daily, which is usually given in three divided doses a day. However, the doctor may tell you to take up to 14g. People with medical conditions that may affect excretion of glutamine, such as people with kidney or liver disease, should always ask their doctor before beginning any new supplements. Glutamine supplements are used for many different issues, however not all of them have strong studies behind them. Although you should ask your doctor about supplements, they are generally available over the counter in pharmacies and health food stores. They usually come as L-glutamine and may be part of a protein supplement. The supplement should state if it is naturally derived or synthetic. A lot of supplements seem to be derived from plant sources so they are vegetarian, but you should always check the label. Glutamine is available as capsules, a powder, a liquid, and as tablets. The powder and liquid form may be better for those who have trouble swallowing or are using the supplement for stomatitis. There are certain rules you need to follow when taking glutamine. It can be taken with or without meals, but make sure you do not take it with food or drinks that are hot. This is because glutamine is an amino acid which can be affected by temperature. Glutamine should only be taken with cold or room temperature liquids. Glutamine powder or liquid can be mixed with water or juice with a low level of acidity like apple or carrot juice. Taking glutamine with acidic juices (like orange or grapefruit juice) or hot liquids will degrade the glutamate  and therefore diminish any benefits. As glutamine is naturally occurring in the body, it rarely produces any adverse side effects. However, excessive glutamine consumption should be avoided as it can lead to an upset stomach. You should also consult with your doctor before taking glutamine if you have liver or kidney disease, or if you're pregnant or breastfeeding. It may be necessary to decrease your dosage or stop taking glutamine altogether.  It is generally recommend to avoid very high doses of any supplement, including glutamine, unless prescribed by your doctor for specific conditions Be aware that glutamine is completely different from glutamate, glutamic acid, monosodium glutamate, and gluten. Therefore, people suffering from gluten intolerance do not need to worry about having an adverse reaction to glutamine. However, in some rare cases, people will experience a bad reaction to glutamine. Symptoms include stomach pain, vomiting, headache, sweating, and joint pain. If this is the case, you should stop taking glutamine immediately and consult your physician.
Educate yourself about glutamine. Find natural sources of glutamine. Ask your doctor about glutamine supplements. Consider different forms of supplements. Take the supplement appropriately. Know side effects and warnings.