White hair and oxidative stress: what role does the enzyme play?

White hair and catalase – a natural avenue to explore

White hair is often perceived as a visible sign of aging. However, its premature appearance in some young adults raises questions. Among the mechanisms studied, the action of an enzyme called catalase draws attention. Linked to oxidative stress and the accumulation of hydrogen peroxide, this enzyme is believed to play a role in the preservation of hair pigmentation. This article explores natural approaches to understand and support this mechanism.

Cheveux blancs

White hair: a natural phenomenon, but sometimes premature

The whitening of hair, or canities, is caused by a progressive decrease in melanin production. This generally occurs from the age of 40–45, but:

  • In some people, it begins as early as 20 or 30 years old;
  • The origin may be genetic, but also linked to the environment or metabolism;
  • The loss of colour often starts at the temples or the roots.

Therefore, premature canities can signal an internal imbalance that should not be overlooked.

The role of oxidative stress in hair aging

Oxidative stress is caused by an excess of free radicals, often generated by:

  • Exposure to pollution or UV rays;
  • An unbalanced diet;
  • Smoking or alcohol;
  • Chronic stress.

These free radicals attack cells, including those responsible for hair pigmentation. As a result, melanocytes are damaged and melanin decreases. This creates a favourable environment for the appearance of premature white hair.

Stress

Catalase: an essential natural enzyme

The catalase enzyme is present in the majority of human cells.

Its function?

To break down hydrogen peroxide (H₂O₂) into water and oxygen. This is crucial because:

  • H₂O₂ is a powerful oxidant naturally produced by the body;
  • In excess, it can damage pigment cells;
  • Catalase acts as a natural “cleaner” of this compound.

This endogenous enzyme could indirectly help maintain a cellular environment compatible with hair pigmentation.

Catalase and hydrogen peroxide: a key balance for preserving pigmentation

Under normal conditions, a balance is maintained between the production of H₂O₂ and its elimination. However:

  • A catalase deficiency can lead to a local accumulation of hydrogen peroxide;
  • This accumulation could inhibit tyrosinase, an enzyme essential for melanin production;
  • This would result in a loss of hair colour.

Maintaining this balance is therefore important for hair vitality.

Decrease in catalase with age: a hypothesis for hair graying

The production of catalase naturally decreases with age. This phenomenon is influenced by:

  • Cellular ageing;
  • A diet low in antioxidants;
  • Chronic inflammatory conditions.

Possible consequences:

  • Less catalase → more H₂O₂ → localised oxidative stress;
  • Progressive alteration of follicles → white hair.

It therefore becomes relevant to adopt strategies that support enzymatic production.

Endogenous antioxidant enzymes and nutrition: complementary mechanisms

In addition to catalase, other endogenous enzymes contribute to oxidative balance:

  • Superoxide dismutase (SOD): converts superoxides into hydrogen peroxide;
  • Glutathione peroxidase: neutralises peroxides;
  • Thioredoxin
Riche en zinc

Their proper functioning is supported by:

  • A diet rich in minerals such as zinc, selenium, and copper, which contribute to the protection of cells against oxidative stress and the normal functioning of enzymes;
  • The presence of B vitamins, particularly B2, B6, and B12, which are involved in normal energy metabolism, cellular function, and play a role in methylation reactions, essential for the production of many enzymes in the body;
  • Plant-derived polyphenols.

Thus, a varied diet indirectly supports the enzymatic defence mechanisms.

Diet and supplements: naturally supporting endogenous catalase?

Certain natural sources can support the proper functioning of catalase:

Beneficial foods:

  • Green leafy vegetables (spinach, kale);
  • Broccoli and cabbages (rich in sulphur and antioxidants);
  • Sunflower seeds, almonds, Brazil nuts;
  • Liver, egg yolk, oily fish.

Potentially useful supplements:

  • Zinc, copper, and manganese, which contribute to the normal functioning of enzymes and are involved in biological processes that neutralise free radicals;
  • Vitamin B12, which plays a role in cell division and methylation reactions, supporting the synthesis of certain enzymes;

⚠️ These supplements do not replace a balanced diet but can be incorporated on the informed advice of a healthcare professional.

Premature gray hair: risk factors and prevention

Here are the main identified risk factors:

  • Genetics (often the main cause);
  • Nutritional deficiencies: iron, B12, copper;
  • Accelerated cellular oxidation;
  • Smoking, which reduces tissue oxygenation;
  • Chronic stress, which increases free radicals.

For natural prevention:

  • Eat a colourful and varied diet;
  • Engage in regular physical activity;
  • Limit alcohol, refined sugar, and processed foods;
  • Include plant-based sources rich in antioxidants.

Catalase and gray hair: what we know today

The connection between catalase and hair whitening remains an interesting area of research. Currently, we observe:

  • Growing interest in antioxidant enzymes in hair care;
  • Integration of catalase in certain cosmetic products or supplements;
  • Necessary caution regarding commercial claims.

The most coherent approach remains that of overall support for oxidative balance, avoiding reliance on a single active ingredient.

The link between catalase and hair whitening remains an interesting line of research. Currently, we observe:

  • Growing interest in antioxidant enzymes in hair care;
  • Incorporation of catalase in certain cosmetic products or supplements;
  • Necessary caution in the face of commercial promises.

The most coherent approach remains that of overall support of oxidative balance, avoiding reliance on a single active ingredient.

Conclusion: A promising enzyme in a comprehensive approach

Catalase, naturally produced by the body, although neither miraculous nor isolated, is part of a natural enzymatic orchestration that can indirectly influence hair vitality.

By adopting a varied and balanced diet, maintaining lifestyle habits that support cellular well-being, and respecting natural biological rhythms, it is possible to better support the internal processes linked to the appearance of white hair. Observing, understanding, and supporting the body naturally: a long-term approach more powerful than any immediate promise.

Scientific bibliography (selection)

  • Wood JM et al. "Senile hair graying: H₂O₂-mediated oxidative stress affects human hair color." FASEB J. 2009.
  • Seiberg M. "Age-induced hair greying – the multiple effects of oxidative stress." Exp Dermatol. 2013.
  • Trüeb RM. "Oxidative Stress in Ageing of Hair." Int J Trichology. 2009.
  • Nandi A. et al. "Role of Catalase in Oxidative Stress and Age-Associated Disease." Curr Med Chem. 2019.
  • Herdiana Y. "Gray Hair: From Preventive to Treatment." J Cosmet Dermatol. 2025.