Witch hazel is made from the bark, twigs, and leaves of the American witch hazel shrub (Hamamelis virginiana), a plant native to eastern North America. The product you find on store shelves is typically a steam-distilled extract of these plant parts, mixed with about 14% alcohol and 86% distilled witch hazel water. What gives it that signature skin-tightening effect is a group of plant compounds called tannins, which bind to proteins in your skin and cause tissues to contract.
The Plant Behind the Bottle
American witch hazel grows throughout the northeastern and southeastern United States, stretching from southern Canada down to northern Florida and as far west as Minnesota, Missouri, and eastern Texas. Isolated populations also exist in south-central Texas and east-central Mexico. It’s a small, understory tree that thrives in the shade of larger hardwoods, and it’s unusual for flowering in late autumn when most other trees have gone dormant.
The parts that matter for making witch hazel extract are the bark, twigs, and leaves. The bark is especially rich in the active compounds that give witch hazel its astringent and anti-inflammatory properties. Specifically, the cambium layer just beneath the bark produces the “vaporized essence” that becomes the extract you recognize.
How It’s Processed
Commercial witch hazel is made through steam distillation. Branches and bark segments are loaded into stainless steel vats and steamed for roughly 36 hours. During that time, the steam pulls volatile compounds out of the plant material. The resulting liquid is then scrubbed, reheated back to vapor, condensed, and filtered to produce a clear distillate.
After distillation, alcohol is added as a preservative. The standard commercial formulation is 86% distilled witch hazel and 14% alcohol by volume. This is the classic drugstore product that’s been sold for well over a century. The FDA recognizes witch hazel as an over-the-counter astringent skin protectant, approved for relieving minor skin irritations from insect bites, minor cuts, and scrapes.
Key Compounds in Witch Hazel
The compounds responsible for witch hazel’s effects fall into two main categories: tannins and smaller molecules sometimes called pseudotannins.
Tannins are the heavy hitters. These are medium-to-large molecules (typically 500 to 3,000 grams per mole in molecular weight) that bind to and precipitate proteins. When they contact your skin, they cause surface tissues to tighten and pores to temporarily shrink. Witch hazel contains both hydrolysable tannins, which are built from gallic acid units, and condensed tannins, also known as proanthocyanidins, which are built from a different class of plant building blocks called flavans. One particularly well-studied hydrolysable tannin in witch hazel is pentagalloylglucose, a molecule made of five gallic acid units attached to a sugar core.
The smaller molecules in witch hazel include gallic acid and hamamelitannin. These fall below the 500 gram-per-mole threshold that defines true tannins, so they don’t bind proteins as aggressively. But they have their own biological activity. Research published in PLOS ONE found that these low-molecular-weight compounds can inhibit neuraminidase, an enzyme that certain viruses use to spread between cells. Hamamelitannin is somewhat unique to witch hazel and is one of the compounds that distinguishes it from other tannin-rich plants like green tea.
What’s in the Store-Bought Version
If you flip over a bottle of witch hazel at the drugstore, the ingredient list is short but worth understanding. A typical product contains water, witch hazel leaf water (the distillate), and alcohol at 14% by volume. Beyond that, you’ll often see a few preservatives: benzyl alcohol, methylchloroisothiazolinone, and methylisothiazolinone. These are standard cosmetic preservatives added to prevent bacterial and fungal growth in the bottle.
Here’s the catch with distillation: the process strips out most of the tannins. Tannins are not volatile, so they don’t evaporate with steam the way lighter compounds do. That means the classic distilled witch hazel water on store shelves contains far fewer tannins than the raw bark itself. If tannin content matters to you, look for products labeled as witch hazel “extract” rather than “distillate.” Extracts are made by soaking the plant material in a solvent (usually alcohol or water) rather than steaming it, which preserves more of the tannin content.
Some modern formulations also add ingredients like aloe vera, glycerin, or vitamin E, while “alcohol-free” versions substitute other preservatives for the ethanol. These variations change the feel and gentleness of the product but don’t fundamentally alter the witch hazel component itself.
Distillate vs. Extract: Why It Matters
The distinction between distilled witch hazel and a bark extract is more significant than most labels let on. Distilled witch hazel water is mild, mostly delivering lighter volatile compounds and whatever astringent effect comes from the alcohol content. A true bark or leaf extract retains the full spectrum of tannins, gallic acid, and hamamelitannin that give witch hazel its documented biological activity. Many skincare products now use the extract specifically because it delivers more of these active compounds to the skin.
If you’re using witch hazel as a gentle toner or for basic skin refreshing, the standard distillate works fine. If you’re applying it for specific concerns like inflammation or irritation, an extract-based product will contain more of the compounds that actually produce those effects.