A ubiquitous name now, Glutamine, is changing the world of fitness and health. People who want to lose weight fast for a lean body and burn fat are opting for this supplement. Athletes and bodybuilders are using it to increase their muscle growth and enhance performance. L-glutamine is the common amino acid, which is found abundantly in our body. Furthermore, there are numerous l-glutamine benefits on our health such as it helps in the treatment of constant diarrhea and ulceration as seen in irritable bowel syndrome (1). It also regulates the immune response to various infections and prevents the risk of infections.
L-glutamine is produced in our body and can also be obtained from animal and plant-based proteins. Animal proteins, such as beef, dairy products, fish, turkey, etc., has l-glutamine.
Also, plant-based proteins, such as beans, spinach, cabbage, etc., are a rich source of l-glutamine. Let us see in detail how l-glutamine benefits our health with scientific references.
What is L-Glutamine?
Glutamine also called L-glutamine, or 2,5-diamino-5-oxopentanoic acid is the most common and abundant amino acid found in our system. Glutamine is found in two different forms, D-glutamine and L-glutamine form (2).
Out of these the L-glutamine variation is found in nature and forms approximately 60% of the amino acid in our muscles. L-Glutamine is conditionally essential amino acid. Essential amino acids are those amino acids which need to be consumed in the diet.
L-glutamine is synthesised in our body, but in certain situations, its synthesis can be limited. Especially in premature infants and people with the severe debilitating condition, the production of l-glutamine is compromised.
In such cases, it should be consumed in the diet either via glutamine foods or supplementation. L-glutamine is synthesised predominantly in our skeletal muscles.
In our muscle tissues, enzyme glutamine synthetase facilitates the formation of glutamic acid from the amino acid glutamate. In healthy individuals, the glutamic acid is produced and stored in the muscle.
The muscles release glutamine promptly to maintain the optimal glutamine blood concentration. In some situations of catabolic stress like a severe infection, surgery or exhaustive exercise, the production of glutamine is compromised.
Also, the glutamine reserves in skeletal muscle deplete and its functions inhibit. In these situations, dietary supplements of l-glutamine are advised (3).
1. Aids in muscles build ups and growth
Glutamine assists in increasing the muscle-protein synthesis by around 8-9%. Glutamine reduces time to full muscle recovery of strength. During exercise, it protects against the adverse effects of oxidative stress chemicals.
In a way, your body muscles demand more glutamine than what your body could produce naturally. Consumption of l-glutamine supplements soon after an intense workout session can boost your strength and helps in muscle build ups.
In other words, it improves the beneficial effects of high-intensity training on the muscle-protein synthesis. It also causes suppression of the loss of muscle in patients after an injury or surgery.
L-glutamine benefits not only bodybuilders but also sportsperson, who are involved in different kinds of sports. Glutamine also assists the increase in lean body mass, improves metabolism and detoxification at the cellular level (4).
2. Improves performance in different sports
An enhanced vertical jump performance has demonstrated improvements in the initial rate of power production compared to a placebo supplement.
Glutamine benefits athletes in the improvement of their running performance since it increases the time until muscular exhaustion (5). It diminishes the effect of delayed-onset muscle soreness.
Glutamine enhances the reaction time following exhaustive endurance exercise. Glutamine supplements have shown to reduce the perception of fatigue in football players and athletes.
Optimal glutamine levels in the blood are essential for its function as a neurotransmitter. It helps improve memory and increases the focus and concentration in athletes (6).
3. Increases immunity level
Studies have shown that glutamine benefits trauma and surgical patients where it reduces the incidence of infection (7). It also reduces the length of time spent in the hospital.
Furthermore, glutamine improves intestinal function and reduces susceptibility to infection. It may also restore critical immune system markers like T cell counts, Ig A serum following any heavy load resistance training, thus reducing the risk of infection post training.
4. Promotes growth hormones
Studies have shown that glutamine might increase plasma arginine and glutamate concentrations, the amino acids both with the potential to improve growth hormone secretion.
It might convert to citrulline in the small intestine which supports renal arginine synthesis, a known stimulus for growth hormone secretion (8).
Glutamine also converts to glutamate which provides an incentive for directly activating somatotropic growth hormone release. Studies have shown that L-Glutamine also enhances the cardiac hormone levels to assist better management of heart function and blood pressure.
5. Maintains healthy gastrointestinal tract
L-glutamine benefits people by protecting the mucous membrane of the oesophagus and intestines. The health of this mucous membrane is essential as it blocks bacterial infiltration during digestion.
People with irritated bowel syndrome and leaky gut have a compromised gastrointestinal tract lining causing the bacteria to enter our bloodstream. L-glutamine boosts immune cell activity in the gut, helping prevent infection and inflammation.
It also helps repair the intestinal tissue. L-glutamine used for energy production; it can support the reduction of abdominal spasms (9).
6. Promotes a healthy brain
Our central nervous system has glutamine in abundance. Here, glutamine participates in different metabolic activities. It is a precursor of the neurotransmitter amino acids. Glutamine metabolism disturbance can lead to different pathological conditions such as epilepsy, bipolar disorder, anxiety, depression, etc. (10)
7. Glutamine benefits type 2 diabetes
The concentration level of glutamine amino acid is low in case of type 2 diabetic patients. A study shows that 30 gram of glutamine supplements per day after each meal can reduce blood glucose level (11).
Another study was done on 13 adults with type 1 diabetes. They went through exercise session twice in a four-week period. Oral glutamine supplement was given before exercise and each meal. On both days, oral glutamine supplementation decreases blood glucose level.
Causes of l-glutamine deficiency
Deficiency of l glutamine occurs when our body is in catabolism and oxidative stress. A decrease in intake of L-glutamine can cause severe malnourishment, increased susceptibility to infections, and faltering growth. The conditions leading to the decline in the glutamine levels are,
- Extreme stress and intense exercise can cause muscle shock (12).
- Trauma or any significant infections leading to a hospital stay for an extended period.
- Cancer patients undergoing radiotherapy and chemotherapy.
- People with immunocompromised conditions such as AIDS.
- Chronic gastrointestinal disorders, such as Crohn’s disease, or inflammatory bowel disease (13).
Athletes or bodybuilders require l-glutamine supplementation since they go through intense workouts or sports session. For them, l-glutamine foods are not sufficient since they need more than what an average person requires.
Sometimes, an average person’s body may not be able to produce glutamine in sufficient quantity. So, it becomes vital to consume foods that are high in l-glutamine.
The dietary sources of glutamine include especially the protein-rich foods like beef, chicken, fish, dairy products, eggs, bone broth. It is also found in vegetables like beans, beets, cabbage, spinach, carrots, parsley. Other sources are wheat, papaya, Brussel sprouts, celery, kale and fermented foods like miso.
L-glutamine dosage (Supplements)
Additional supplementation of L-glutamine is the key to sustain a positive net protein balance and maximise its benefits. Orally ingested glutamine can start with 0.1g/ kg of body mass and result in a 50% rise in the plasma glutamine concentration.
When taken alongside a protein supplement Glutamine seems to provide even more superior advantages to glutamine. Therefore, it is advised to add a glutamine powder directly to your post-exercise shake.
The oral powder form of glutamine should be taken with a meal or snack unless directed otherwise. Dissolve your dose of glutamine oral powder in at least 8 ounces of hot or cold liquid.
Alternatively, you can also mix the glutamine powder with soft food such as applesauce, or yoghurt. For those on an extended bed rest post-surgery, always combine the glutamine powder with water and infuse it directly in the feeding tube using a syringe.
Glutamine is a part supplement of a complete treatment program which also includes a special diet, tube feedings, and IV fluids.
For the treatment of short bowel syndrome, glutamine is prescribed for up to 17 weeks. The tablets of glutamine are taken on an empty stomach, at least 1 hour before or 2 hours after a meal. An overdose of glutamine is not expected to produce life-threatening symptoms.
L-glutamine side effects
Glutamine is considered safe for adults when taken by mouth in doses up to 40 grams daily. Side effects of L-glutamine supplements are infrequent. Side effects if any includes
- Hives which cause difficulty in breathing, swelling of your face, lips, tongue, or constriction felt in the throat.
- Nausea, vomiting, stomach pain, gas.
- A mild skin rash or itching.
- A headache, dizziness or a tired feeling.
- A severe dry mouth and a runny nose.
- Mild chest pain and increased sweating.
- Slight pain and tenderness in joints.
- People with cirrhosis or severe liver disease should avoid glutamine supplements as it might make these conditions worse.
Final words on l-glutamine benefits
Glutamine is produced naturally in our body. It is essential for growth and maintenance of our body. Infants receive their dosage of glutamine through weaning.
Those with infections, debilitating diseases have a depletion in the reserves of glutamine. In such instances, oral glutamine supplements become a necessity. L-glutamine benefits majorly athletes, bodybuilders and sports person. They consume glutamine in various forms and experience positive results in their performance, endurance and concentration.
Glutamine is a very safe and essential amino acid. If you are under stress or going through rigorous physical activity, then you should consult your dietician to incorporate an adequate amount of glutamine in your diet.