“Drink more water for better skin” sounds plausible, but the research does not support the dramatic claims often attached to it.

A systematic review published in 2018 found only six eligible studies on fluid intake and skin properties in healthy adults. The authors judged the overall evidence to be weak in both quantity and methodological quality. They found that additional water intake may produce a small increase in hydration of the outer skin layer, especially in people who previously drank relatively little, but they concluded that more research was needed. Akdeniz et al., 2018

More recent research also suggests that moisturizers have a clearer direct effect on skin hydration than simply adding more drinking water. In a 2024 study of 43 healthy women, moisturizer use had a more favorable effect on measured skin hydration than additional water intake. Seol et al., 2024

So the evidence-based answer is modest: normal hydration matters, and extra water may slightly improve measured skin hydration in some low-intake individuals, but drinking more water is not a proven replacement for skin care or treatment of dry skin.

What does “skin hydration” actually mean?

The outermost layer of the skin, the stratum corneum, has to retain enough water to function normally.

A review of skin hydration mechanisms explains that water retention in this layer depends on natural moisturizing factors inside skin cells and on lipids between those cells that help limit transepidermal water loss. Verdier-Sévrain and Bonté, 2007

That is why whole-body hydration and skin-surface hydration are related concepts but not the same thing.

Drinking water adds fluid to the body. A moisturizer acts locally on the skin barrier and can help reduce water loss or improve water retention at the surface.

The distinction matters because dry skin is often a barrier problem, not simply evidence that a person failed to drink enough water.

What did the systematic review find?

The most useful overview is the 2018 systematic literature review by researchers from Charité in Berlin. Akdeniz et al., 2018

The review searched PubMed and Web of Science and included six studies in healthy adults. The authors reported:

a slight increase in stratum corneum and deeper skin hydration after additional water intake;
the effect appeared more noticeable in people with lower prior water consumption;
some studies reported reduced clinical dryness and roughness;
small changes in extensibility and elasticity were reported;
findings for transepidermal water loss, sebum and skin pH were unclear.

The most important sentence in the paper is not the positive one. It is the limitation: the authors considered the evidence weak and called for better research.

That means the review cannot justify claims that drinking extra water reliably transforms the appearance or health of everyone’s skin.

What do individual water studies show?

One 2015 study followed 49 healthy women and examined skin physiology after changes in dietary water intake. The researchers reported improvements in several skin hydration measurements, particularly among women with lower habitual water intake. Palma et al., 2015

Another 2015 study asked 34 healthy women to add 2 litres of water per day for one month. The authors reported increased superficial and deeper epidermal hydration, particularly in participants who had previously consumed less water. They did not find a significant change in transepidermal water loss. Palma et al., 2015, Skin Research and Technology

These studies are useful, but they are small. They do not establish that every person should add 2 litres to their normal intake, and they do not demonstrate broad cosmetic outcomes such as reversal of skin aging.

The 2018 systematic review considered these and other studies and still rated the overall evidence as weak. That broader assessment should carry more weight than any single positive study.

What does newer research say about water versus moisturizer?

A 2024 study compared additional water intake, moisturizer use, both interventions and control conditions in healthy women grouped by their usual water intake. Seol et al., 2024

The researchers measured stratum corneum hydration and transepidermal water loss over four weeks. They concluded that the amount of water consumed might be related to skin barrier function, but moisturizer application had a more favorable effect on skin hydration than additional water intake.

This fits what dermatologists recommend in practice.

The American Academy of Dermatology recommends regular moisturizer for dry skin, especially immediately after washing while the skin is still damp. It also recommends short warm showers rather than long hot ones, gentle fragrance-free products and protection from dry environments.

Those recommendations target the skin barrier directly.

Will drinking more water cure dry skin?

There is not enough evidence to say that it will.

The 2018 systematic review explicitly concluded that research is still needed to determine whether increased fluid intake decreases signs of dry skin. Akdeniz et al., 2018

Dry skin can result from low humidity, frequent washing, hot water, irritating products, age, skin disease and other medical factors. The American Academy of Dermatology notes that persistent or severe dry skin can also be associated with conditions such as atopic dermatitis, psoriasis or kidney disease. AAD

If someone is genuinely dehydrated, restoring normal hydration is important for overall health. That is different from prescribing extra water as a treatment for chronic dry skin.

Does more water prevent wrinkles or skin aging?

The available hydration studies do not establish that drinking extra water prevents or reverses wrinkles.

Some small studies measured biomechanical properties such as elasticity, but the 2018 systematic review judged the body of evidence weak. Akdeniz et al., 2018

That is not enough to convert a change in an instrument measurement into a claim that extra water is an anti-aging treatment.

If a product, post or article promises that a specific number of glasses will remove wrinkles, that claim goes beyond the evidence reviewed here.

What about acne?

The studies in the 2018 systematic review were designed to investigate skin hydration and related physiological measures. They do not establish extra water intake as an acne treatment. Akdeniz et al., 2018

Acne is a medical skin condition with established treatment approaches. Drinking enough for normal hydration is sensible, but it should not replace evidence-based acne care.

How much water should you drink for your skin?

There is no scientifically established “skin hydration dose” of water for healthy adults.

General daily water needs vary with sex, diet, climate, activity, pregnancy, breastfeeding and health. Official recommendations also refer to total water from food and drinks, not just plain water.

Our guide How Much Water Should You Drink a Day? compares EFSA, NHS and US National Academies guidance and explains why their numbers differ.

If you already drink normally and are not dehydrated, current skin research does not show that forcing substantially more water guarantees a visible skin benefit.

What is better supported for dry skin?

For ordinary dry skin, dermatology guidance focuses on protecting and restoring the skin barrier.

The American Academy of Dermatology recommends measures such as:

applying moisturizer when the skin is still damp after washing;
using creams or ointments rather than thin lotions when skin is very dry;
keeping showers and baths short and warm rather than hot;
choosing gentle, fragrance-free products;
using a humidifier when indoor air is very dry;
seeking dermatology advice if dryness persists or becomes severe.

These recommendations are summarized in the AAD’s dry-skin guidance.

When can hydration still matter?

Normal hydration is still part of normal physiology.

If you have been drinking very little, are losing fluid because of heat or illness, or have other signs of dehydration, correcting the underlying fluid deficit is important. See Signs of Dehydration for the broader clinical picture.

What the evidence does not justify is turning skin appearance into a reason to drink excessive volumes.

More water is not automatically better, and very high fluid intake can be harmful in some circumstances.

What you can reasonably conclude

Research suggests that increasing water intake may slightly increase measured skin hydration, especially in people who previously consumed relatively little water.

But the evidence base is small and methodologically weak. It does not show that extra water is a universal treatment for dry skin, acne, wrinkles or skin aging.

For dry skin specifically, direct skin-barrier care such as appropriate moisturizer has stronger practical support and, in a 2024 comparative study, produced a more favorable hydration effect than additional drinking water.

Drink enough for normal health. Do not expect an arbitrary extra litre or two to function like a dermatological treatment.

Sources and further reading

This article provides general information. Persistent, painful, cracked, bleeding or otherwise concerning skin changes should be assessed by a healthcare professional.