Dry skin from within: which supplements really help?

The short answer: Essential fatty acids—omega-3 and gamma-linolenic acid—have the strongest evidence for dry skin. In controlled studies, moisture loss through the skin fell measurably after around twelve weeks. Supplements do not replace skincare. They work at a different level: the building blocks that make up your skin barrier.

Why creams sometimes are not enough for dry skin

Dry skin is rarely simply a shortage of water. It is almost always a shortage of lipids. The outermost skin layer works like a brick wall: skin cells are the bricks, and the lipids between them are the mortar. When mortar is missing, water evaporates freely—transepidermal water loss increases, leaving skin tight, flaky and sensitive.

A good cream replenishes this mortar from outside and seals the surface. This works while it is applied. What it cannot do is change the body's own lipid production. This is where nutrition comes in: the body cannot make two important building blocks of this lipid layer itself. Linoleic acid and alpha-linolenic acid are essential and must come from food.

Omega-3 and gamma-linolenic acid: where the evidence is strongest

For essential fatty acids, there are randomised, placebo-controlled trials measuring skin parameters—something still uncommon in this field.

Two double-blind, placebo-controlled studies published in the Journal of Cosmetic Dermatology in 2024 investigated omega-3 supplementation in healthy adults with normal to dry skin. After twelve weeks, participants had statistically significantly lower transepidermal water loss and improved skin hydration and elasticity compared with placebo. An interesting additional finding was a linear association between the omega-3 index measured in blood and improvements in barrier measurements. Those with lower levels beforehand benefited most.¹

For gamma-linolenic acid—an omega-6 fatty acid from evening primrose or borage oil—a Japanese study investigated people with dry skin and mild atopic dermatitis. Hydration measurements and barrier function also improved during the study.²

The mechanism is plausible and well described: EPA and DHA compete with arachidonic acid for the same enzyme pathways, shifting the balance from inflammation-promoting towards inflammation-resolving messengers. For skin prone to redness, sensitivity and dryness, this is the key mechanism.³

What a manufacturer may claim—and what it may not

This is where honesty can be uncomfortable, which is precisely why it belongs here. In the EU, the Health Claims Regulation determines which health claims may be made about food supplements. Only claims on the list in Regulation (EU) No 432/2012 are permitted.⁴

There is no authorised skin health claim for omega-3 fatty acids. Approved EPA/DHA claims concern heart function, the brain and vision. That does not make the studies above worthless; it means the evidence has not yet been sufficient for an officially authorised skin claim. Selling a fish-oil supplement with the promise of “beautiful skin” is not legally covered.

Authorised skin claims do exist for a limited group of micronutrients:

The wording matters. “Maintenance of normal skin” means a deficiency is harmful and correcting it helps. It does not mean that more is better. Vitamin A also has an upper limit, and high-dose vitamin A should explicitly be avoided during pregnancy.

What changes are realistic, and when?

In adults, the epidermis renews itself in around four weeks, taking longer with age. Anything working through metabolism needs at least one such cycle before changes become visible. The cited studies lasted twelve weeks—a realistic period for assessment.

• Weeks 1–4: Nothing visible. This is normal and not a reason to stop.
• Weeks 4–8: Often, less tightness is noticed first, particularly after cleansing.
• Weeks 8–12: If changes occur, this is when they tend to show: more even texture and less flaking.
• No change after 12 weeks: Stop and look for the cause elsewhere.

What to look for when buying

The most common mistake is looking at capsule size instead of contents. “1,000 mg fish oil” says nothing about the actual EPA and DHA content—it could be 300 mg or 700 mg.

• EPA and DHA listed separately. Each should have its own milligram amount on the pack. When this breakdown is absent, the content is often lacking too.
• Gamma-linolenic acid rather than “omega-6”. Most people already consume plenty of omega-6. The specific fatty acid from evening primrose or borage oil is what matters, not the whole group.
• Vitamin E in the formula. Unsaturated fatty acids oxidise. Added vitamin E protects the oil in the capsule—a sign that shelf life has been considered.
• Take with a meal. Fat-soluble substances need fat for absorption. Some is lost when taken on an empty stomach.
• One supplement, not five. Combining several products can quickly double up doses, especially of vitamin A and zinc, which have upper limits.

One often overlooked point: if you take blood-thinning medication, discuss higher-dose omega-3 with your doctor first. This interaction is known and relevant in practice.

When supplements are not the answer

Dry skin often has a cause that no capsule can solve. Please seek medical advice if:

• dryness appeared suddenly and is pronounced;
• it comes with fatigue, feeling cold or weight changes, which may involve the thyroid;
• you take medication that dries the skin, such as isotretinoin, some blood-pressure or cholesterol medicines, or diuretics;
• the skin is weeping, intensely itchy or inflamed.

The most common cause of all is showering too hot and too long, or cleansing too harshly. Before taking anything, review cleansing for dry skin. An overly harsh cleanser can damage more than a supplement can rebuild.

How to combine care from inside and outside

Internal and external care are not alternatives; they address different needs. This order makes sense:

1. First, make cleansing gentler. Choose mild, lipid-preserving products from our selection for dry skin.
2. Then support the barrier externally. Use a humectant under a lipid-rich cream. Our article on hyaluronic acid in skincare explains why this order matters.
3. Only then consider supplements. Essential fatty acids such as Skin Omegas+, or Skin Moisture Lock when moisture retention is the priority. Those seeking micronutrients with authorised skin claims can find a combination in Skin Complete.

Explore the full supplement range, including formulations from Advanced Nutrition Programme, a brand that has formulated exclusively for skin for over twenty years. Learn more on our brand page.