Skip to content
NEXT IN SKIN What’s next in Korean & Japanese skincare.

Birch sap

1 products

Birch sap is the watery liquid drawn from birch trees in early spring, before the leaves open. On an ingredient list it usually appears as Betula platyphylla japonica juice, and it is used the way rice bran water is: as a replacement for some or all of the plain water in a formula, which lets a brand put a botanical at the very top of the list.What is actually in birch sap is a dilute mixture of minerals such as potassium, magnesium, manganese and zinc, simple sugars, amino acids and small amounts of vitamins and polyphenols. Available research points to mild antioxidant and soothing activity, and a small clinical study of a birch juice spray reported benefits for skin repair. That is a modest evidence base, and the concentration in a finished cosmetic is inherently low, so it is better understood as a pleasant hydrating base rather than an active with a mechanism of its own.Brands describe birch sap as light, clean hydration that does not weigh skin down, and they tend to build watery, fast-absorbing textures around it. That texture claim is the honest part of the story, and it is why birch sap sunscreens have such a following.It suits combination and oily skin that wants hydration without heaviness, and sensitive skin looking for a low-irritation formula. Birch pollen allergy is worth noting: reactions to topical birch sap appear to be uncommon, but if you have a strong birch allergy, patch test first. Anyone after visible correction of spots or lines should treat this as the comfortable base layer, not the treatment.It layers with everything, and it works especially well as the hydrating half of a sunscreen or a light gel over a serum.Ours is in the Round Lab Birch Juice Moisturizing Sun Cream SPF50+ PA++++.