What Is Glutamine?
Glutamine is the most abundant amino acid in your body. It plays many important roles in your health, including:
- Making proteins for muscle tissue
- Strengthening your intestines
- Supporting immune system cells
Your body does make glutamine, but you also get it from foods such as wheat, peanuts, corn, and milk. It's rare to have low levels of glutamine unless you are ill or injured. In that case, your doctor may suggest a glutamine supplement.
Types of Glutamine
There are two types of glutamine: L-glutamine and D-glutamine. While they are very similar, they have slightly different molecular structures. Many foods contain abundant amounts of L-glutamine, while D-glutamine is much less commonly found in nature. Because L-glutamine is so common, it’s often referred to simply as glutamine when sold as a supplement.
Glutamine Sources
Your body makes most, if not all, of the glutamine that it needs. Studies estimate that the body produces about 40-80 grams of glutamine every day. But you also can get glutamine from your diet and supplements.
Dietary sources of glutamine
Protein-rich animal sources provide the most glutamine, but other foods contain it as well. Common sources are:
- Beef, pork, poultry, and other meat
- Fish and shellfish
- Eggs, milk, yogurt, cheese, and other dairy products
- Nuts, tofu, and other plant-based protein sources, such as legumes
- Some vegetables, such as corn, potatoes, spinach, and cabbage
- Grains, such as oats, wheat, and rice
Glutamine supplements
You can also buy glutamine in the form of supplements over the counter or as a prescription. It’s available in the following formats:
- Tablets
- Powders
- Capsules
Glutamine Benefits
Glutamine has many benefits for your musculoskeletal, immune, and digestive systems. Research is also examining whether supplemental glutamine has any benefits. Studies show that people with certain illnesses and injuries may benefit from these supplements, mainly because they tend to have low levels of the amino acid.
According to research, these are the possible benefits of glutamine:
Supports the immune system
Glutamine is the main fuel source for your body’slymphocytes, white blood cells that fight infection and disease. But your blood’s glutamine levels drop when you’re sick or injured, reducing theseimmune cells’ ability to defend your body.
While there’s conflicting evidence on whether it boosts immunity in healthy people, studies show it can improve recovery times and reduce complications when you’re sick.
Maintains gut health
Glutamine helps strengthen your intestinal lining, protecting against damage and ensuring your body absorbs the nutrients it needs. Because of this, researchers are looking into whether glutamine supplements can help people with digestive disorders, such as Crohn’s disease and irritable bowel syndrome (IBD) . So far, study results are mixed, with some showing a small benefit and others showing none. So, while getting enough glutamine is important to maintain normal gut health, it's not clear if supplemental glutamine can be helpful in cases of gut disorders.
May help muscle recovery
Glutamine is necessary to maintainmuscle protein, which is why it's a popular sports supplement. There are many claims about its ability to speed muscle recovery and improve athletic performance. Some study results show that it reduces musclefatigue and improvesexercise recovery, but this has not been shown to translate into better athletic performance.
Helps treat sickle cell disease
In sickle cell disease, your red blood cells become hard and sticky. They also change their shape and resemble a sickle. When that happens, blockages develop in your blood vessels, blocking the flow of blood and making you more susceptible to infection, anemia, and other serious complications. Glutamine supplements have been shown to help reduce red blood cell damage, keeping them from becoming sticky and misshapen. This helps blood to flow normally.
Helps treat skin burns
Some research suggests that glutamine may help speed the healing of burns and reduce related infections. However, more studies need to be done to confirm whether glutamine has a real role in burn care.
Helps in postsurgery recovery
Glutamine may reduce your risk of infection that can result from surgery, such as pneumonia. Some research shows it can help reduce the length of postsurgical hospital stays. But there isn't enough high-quality evidence yet for it to be routinely used after surgery.
Glutamine Side Effects
Because our bodies make glutamine and it’s found in many foods, it’s considered safe in normal amounts. However, there are some potential health risks, sotalk to your doctor before adding a glutamine supplement to your diet.
Common side effects of glutamine
The most common side effects of glutamine supplements are a cough andchanges in bowel movements. Other possible side effects include:
- Abdominal pain
- Constipation
- Headache
- Nausea
- Pain in the back, legs, hands or arms
Other more serious side effects that require medical attention include:
- Pain in the back, legs, hands or arms
- Confusion
- Dizziness
- Fainting
- Pain while peeing
- Peeing more than usual or sudden decrease in pee
- Lower back or side pain
- Headache
- Racing heartbeat
- Difficulty breathing
- Swelling in the face, lips, or tongue
Long-term side effects of glutamine
High intake over time may change how your body uses amino acids, including glutamine itself. The long-term impact of this change is unknown, but it may raise the risk of health problems. For example, taking glutamine supplements may support your immune system in the short term, but its long-term effects on the immune system remain unknown. Some evidence suggests that it could affect metabolism in a way that increases the risk of metabolic syndrome, diabetes, and coronary artery disease.
Glutamine toxicity
Experts say that even high doses of glutamine likely cause no harm. However, at least one case of liver toxicity has been reported. More research is needed to confirm whether glutamine is safe to take long-term and if it can be toxic at high doses in both the short and long term.
Who should not use glutamine supplements?
There isn’t enough evidence to confirm that glutamine is safe for pregnant or breastfeeding women. Glutamine supplements may worsen symptoms ofliver andkidney disease in people with these conditions. Elderly people often have reduced kidney function and may need to take lower doses of glutamine.
If you have Reye’s syndrome —a rare and potentially fatal disease that causes the liver and brain to swell — do not take glutamine. Taking glutamine if you have a psychiatric or seizure disorder may not be safe. To be sure it is safe for you, talk to your doctor before you take glutamine supplements.
Glutamine Dosage
The correct dosage of glutamine varies from person to person and what you are taking it for. If you are using an over-the-counter supplement, refer to the dosage guide on the label or ask your doctor. If you have a specific condition for which your doctor has recommended a glutamine supplement, they will give you dosage instructions.
Do You Need Glutamine Supplements?
Most people have enough glutamine. Your body makes it and it's abundant in food. Therefore, most people do not need a glutamine supplement. If you are ill for a long time or have an injury, you may need extra glutamine. Your doctor can help you decide if you need a supplement and how much to take.
Takeaways
Glutamine has important functions that support your overall health. Your body makes it, and you get it from your diet as well. While glutamine supplements may help treat certain health conditions, such as sickle cell disease, it’s not clear whether healthy people get any benefits from glutamine supplements. If you’re considering taking glutamine supplements, ask your doctor if it’s safe for you to do so.
Glutamine FAQs
Is it good to take glutamine every day?
Glutamine is considered generally safe, but researchers don’t yet know whether it’s safe to take glutamine supplements for a long time. Most people don't need to take glutamine supplements.
Is glutamine good for the skin?
Some research has shown that glutamine can help heal burns.
Is L-glutamine safe for kidneys?
In healthy people, L-glutamine should be safe for the kidneys, but people with kidney disease should not take glutamine. Older people, whose kidneys may no longer function as well as they used to, should talk to their doctor before taking glutamine.
What food is highest in glutamine?
Beef has the highest amount of glutamine, followed by tofu and eggs.
