Drinking water to reduce acne?

Acne is a chronic inflammatory disease of the pilosebaceous follicles, characterised by the emergence of inflammatory spots (papules, pustules, cysts) and/or comedones (blackheads, whiteheads), which can be located on any part of the body (torso, back, face, etc.).

These skin lesions are caused by an excessive production of sebum (hyperseborrhea) or a change in its quality (dysseborrhea), an hyperkeratinization, and the abnormal multiplication of Cutibacterium acnes which is usually well tolerated.

Today, various tips and tricks are frequently shared on forums and social media on how to prevent or combat acne lesions. Drinking plenty of water is among these. But does this behaviour actually have an effect on acne?

Increasing water intake internally enhances skin hydration.

A study conducted over 30 days with 49 women has shown that an additional dietary intake of water (2 litres per day) appears to increase skin hydration and reduce skin dryness. However, the evidence supporting this observation is weak and the clinical relevance is not yet clear.

Indeed, it has been observed that dry skin can lead to an overproduction of sebum. When the skin's water content is reduced, the skin must "compensate" for this lack of external hydration by increasing sebum secretion in order to replenish the skin's natural protective barrier.

However, the increase in sebum excretion is a causal event associated with the development of acne. Furthermore, if the sebum interferes with the process of follicular keratinisation, the pores can become "blocked", contributing to the formation of spots.

Water consumption would promote detoxification.

The body possesses an efficient detoxification system naturally, and water is a crucial element for the proper functioning of this system. Moreover, it has been demonstrated that drinking water can alter the skin's microbiome.

The sweat glands, primarily the exocrine glands, which are responsible for perspiration, are present on virtually all skin surfaces and continuously bathe the skin's surface with their secretions, which are primarily composed of water and salt.

The primary role of exocrine sweat is thermoregulation through the release of latent heat due to the evaporation of water. However, the exocrine glands also function to excrete water and electrolytes, and to acidify the skin, which prevents the colonisation and growth of microorganisms, and the elimination of toxins.

For this mechanism to function properly, an adequate intake of water through diet is essential. Proper toxin elimination could prevent the pores from becoming blocked, which could help to prevent skin breakouts. However, research on this subject is limited.

Drinking water could have an impact on the immune system.

A study has highlighted a significant decrease in immune function, through a reduction in the levels of neutrophils, macrophages, natural killer cells ("Natural Killers"), and other immune cells following a marathon-type exertion.

Such an effort is typically associated with intense water loss through perspiration. It is therefore hypothesised that a person's hydration status affects the immune system, and that a lack of water intake has a negative impact on immunity.

It is important to understand that the state of hydration is not the only factor contributing to this phenomenon. Energy balance, thermal stress, and stress hormones also significantly contribute to it.

We hypothesise that acne-associated bacteria, such as Cutibacterium acnes, would therefore be targeted by our strengthened immune system, reducing the risk of developing acne. However, further research is still required to confirm the direct action of drinking water on protection against the bacteria responsible for acne.

Water consumption could regulate blood sugar levels.

A study observed that a low water intake could be associated with a higher risk of hyperglycaemia, suggesting that a higher intake could prevent the onset of hyperglycaemia. Concurrently, SMITH R. N. and his team demonstrated in a study that 12 weeks of low glycaemic index diet significantly reduced the number of acne lesions compared to a diet with a normal to high glycaemic index (high carbohydrate intake).

Research thus suggests that frequent consumption of high glycaemic index carbohydrates may also expose us to acute hyperinsulinaemia, that is, a blood insulin level higher than normal. However, this is implicated in the pathophysiology of acne, due to its association with an increase in the bioavailability of androgens, hormones involved in the stimulation of sebum secretion, and free concentrations of IGF-1, which increase the production of skin cells that can then cause pore obstruction through hyperkeratinisation and thus the appearance of acne spots.