Is drinking lots of water important for skin health?

Is drinking lots of water important for skin health?

One of the most common things I hear from patients is that they drink lots of water every day but they still suffer from dry or irritated skin or acne. They say this to me in a frustrated way – ‘but I drink TONS of water everyday, doc! Why is my face still so dry?’ And I get it: drinking lots of water every day is not so fun, especially if it means you can’t go more than 30 minutes without having to find a bathroom.

To me, the old adage ‘drink more water to get plump hydrated skin’ is nothing but an old wives tale. Our bodies are extremely good at regulating fluid balance – it’s called homeostasis. That’s why if you drink more water than you need, you just pee it out. It’s true that water plays an absolutely crucial role in life because all biological processes require it to survive. The amount of water in your body is dependent on your age; infants are 75% water while an elderly person is only 55%. One of the most important functions of our skin is to protect us from ‘drying out’ – it helps keep the water inside our bodies where it is needed. The stratum corneum is the outermost layer of the epidermis and it provides a tight barrier measuring 15-30 microns to stop water from leaving our bodies. The epidermis itself is 40-140 microns thick and contains approximately 70% water.

Adequate skin hydration is of course critical for maintaining skin health and therefore moisturisers are an important part of basic skin care in order to protect the stratum corneum from the daily insults of the environment such as sun, humidity, wind and detergents. Other strategies to help maintain skin hydration or treat dry skin have also been proposed and this includes the idea of drinking six to eight glasses of water per day. However, we know that the diffusion of water molecules through the stratum corneum is a passive physical process and the ability of the epidermis to hold water is mainly determined by properties of the skin itself, the link between oral intake of water and skin hydration is unclear.

A review article published in 2018 looked at this question to summarise the evidence about a possible association between fluid intake and skin hydration. They found 6 studies which looked at this question. The authors of the review article concluded that the empirical evidence supporting the idea that additional water intake (about what is normally required for life) increases skin hydration reducing skin dryness is weak and, in addition, the clinical relevance is unclear.

What’s my conclusion? Drinking water or fluids in excess of ‘normal’ intake is unnecessary; it doesn’t add to skin hydration or treat acne or just generally lead to ‘healthier’ skin. So if you are drinking water just for the sake of your skin, you don’t need to. But if you like drinking lots of water and find it does make a difference, it is definitely not harmful to your skin.

REFERENCES:

Verdier-Sevrain S, Bonte, F. Skin hydration: a review on its molecular mechanisms. Journal of Cosmetic Dermatology. 2007; 6: 75-82.

Akdeniz M, Tomova-Simitchieva T, Dobos G, Blume-Peytavi U, Kottner J. Does dietary fluid intake affect skin hydration in healthy humans? A systematic literature review. Skin Res Technol. 208; 24: 459-465.