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Understand Glutathione and its Importance in Our Health

Discover the compound that plays a key role in detoxification and free radical protection.

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Glutathione is one of the body’s most important antioxidants. It’s contained in some foods but—because it’s so essential—your body is also able to make it.

What is Glutathione?

Glutathione is made of three amino acids (the smallest unit of protein): glutamic acid, glycine and cysteine. It’s found in varying levels in most body cells, though the highest concentration is found in the liver.

What Does Glutathione Do?

Glutathione has a range of critical functions in the body. In different cells, it:

  • Quenches free radicals

Glutathione is an important antioxidant in the cellular mitochondria—the energy-production factories of the cell.

In fact, cellular mitochondrion glutathione is our main defence against free radicals produced as a by-product of cellular respiration. This means glutathione is essential for our continued production of energy from oxygen and fuel.

Together with compounds called ascorbates, glutathione also participates in the regeneration of vitamin E, which enhances the cooperation of antioxidants.

  • Assists detoxification

Glutathione is involved in both Phase I and Phase II of liver detoxification.

In Phase I, it’s a key neutraliser of the free radicals produced when the liver breaks down toxins. Consequently, glutathione is especially important in organs exposed to toxins, such as the liver, kidney, lungs and intestines.

In Phase II, the liver enzyme glutathione S-transferase takes sulphur and glutathione and combines (conjugates) it with the toxic substance, making it water soluble. This water-soluble form, called a mercaptate, is then excreted in the urine. In order to function, glutathione S-transferase needs plenty of glutathione.

  • Regulates the internal redox environment of cells

Glutathione plays an integral role in the transfer of electrons, otherwise known as redox reactions. These essential reactions control several cellular processes, ultimately sustaining energy and life.

Other functions of glutathione including assisting with amino acid transport, and contributing to the synthesis of the signalling molecules prostaglandins and leukotrienes.

What Causes Low Glutathione?

There’s a general decline in glutathione levels as we age.

When we are exposed to high levels of toxins, glutathione is used up faster than it can be produced or absorbed from the diet. This can also lead to low levels.

A key example of a heavy toxic load is the combination of pesticides and alcohol. The alcohol increases the production of Phase I activated intermediates from the pesticides, but the depletion of glutathione means these toxins hang around longer.

This means more free radicals are released, causing more damage to the liver, brain and nervous system.


What are the Effects of Low Glutathione?

Low glutathione levels are associated with a variety of chronic conditions, such as:

What’s more, without sufficient glutathione to help detoxify substances, we can become more susceptible to toxin-induced diseases. These include:

We can also be at greater risk of heavy metal burden, especially if our Phase I detoxification system is highly active.

How to Increase Glutathione

Glutathione is available through two routes: dietary intake and synthesis by the body. The latter can be supported by certain supplements.

  • Dietary intake

Food sources of glutathione include:

  • Fresh fruit and vegetables
  • Cooked fish
  • Cooked meat

The food form is absorbed well by the intestines and doesn’t appear to be affected by digestive processes. As well as supporting Phase II detoxification, dietary glutathione can also detoxify substances in the intestine before they can be absorbed into the bloodstream.

  • Supplements

Glutathione levels can also be supported by supplementation. As mentioned, glutathione is made from three amino acids, but the rate-limiting amino acid is cysteine. This means if we don’t have enough cysteine, glutathione production stops.

As a supplement, n-acetylcysteine is therefore an effective precursor for glutathione. It’s deacetylated (broken down) in the gut to free cysteine, effectively raising intracellular glutathione in healthy individuals.

  • Intravenous glutathione

One problem that arises is that oral use of glutathione doesn’t seem to be very well absorbed, even with the liposomal products. It’s our estimation that liposomal glutathione orally may be 15-20% absorbed at best.

This then leaves two other options: intravenous glutathione and suppository forms. We provide intravenous glutathione at our clinic for the most competitive rates in London.


For more information on glutathione intravenous administration, please get in touch or call us on 0203 332 0030.

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