What is glutamine?

Glutamine, or L-glutamine, is the most abundant amino acid in the blood and muscles. It plays a role in protein synthesis, immune protection, maintaining intestinal wall integrity and the body's acid-base balance.

It is also used to make the body's own glucosamine, which is involved in cartilage and tendon repair.

Glutamine is not considered an essential amino acid because the body is able to synthesise it from different foods according to its needs.

Moderate, regular exercise increases the level of glutamine in the blood, but extreme stress can significantly reduce it (severe burns, major trauma, surgery, etc.).

The body is at risk of becoming a target for various infections.

This seems to be particularly the case with the so-called "overtraining syndrome".

Athletes, beware of overtraining for good glutamine production

This is a form of exhaustion and weakening of the immune system that affects athletes, for example after a marathon or any other activity that is particularly demanding in terms of physical endurance.

After very intense exercise, muscle glutamine reserves are depleted.

If there is insufficient recovery time to replenish them, a deficiency can occur, making the athlete more susceptible to infection.

Overtraining syndrome does not only affect athletes. 

Symptoms of overtraining can occur in a person who is on a relatively light training programme, but is under significant stress in their daily life.

Symptoms of overtraining include frequent colds, unexplained fatigue or less restful sleep.

They are at odds with the improvement in vitality you would expect from an exercise programme.

Indications

Effectiveness uncertain

Prevention of overtraining syndrome in athletes

Ineffective

Improving physical performance.

Glutamine dosage

Although the results of trials are not always consistent, those that have shown positive results have found that taking 5-10g of glutamine before or immediately after intense exercise helps to prevent a decline in immune defences.

Glutamine source foods

Meat, fish, dairy products, cereals and pulses are good sources of glutamine. It is also found in raw spinach, parsley and miso.

It is estimated that a normal diet in our modern society provides 5 to 10 g of glutamine per day.

Glutamine deficiency

Although the body normally produces all the glutamine it needs, a deficiency can occur during extreme physiological stress caused by a serious accident, severe burns, surgery, serious illness, etc.

In such cases, immune resistance can be compromised, as can the integrity of the intestinal lining, which can lead to the onset of various infections.

Overtraining has also been observed to cause glutamine deficiency.

Interactions

With plants or supplements: not known.

With medication: In theory, taking a glutamine supplement may counteract the effects of anti-epileptic drugs (anticonvulsants).