If you look at the ingredient list of a hair serum or scalp treatment nowadays, you'll see niacinamide more and more often. The ingredient gained popularity in skincare products in recent years and has now found its way into hair products.
But what does niacinamide actually do?
What is niacinamide?
Niacinamide is a form of vitamin B3, also known as nicotinamide. It is a water-soluble vitamin naturally found in foods such as meat, fish, nuts, and legumes. Your body can also produce it from tryptophan, an amino acid.
In skincare, niacinamide has been known for years for its wide range of effects: it strengthens the skin barrier, reduces redness, regulates sebum production, and has anti-inflammatory properties. For hair products, the mechanisms are the same, but applied to the scalp.
What does niacinamide do for your scalp?
The scalp is actually just skin. That sounds logical, but it's often overlooked in the hair care world. Sebaceous glands, hair follicles, the skin barrier – all these structures react to ingredients that also work in facial skincare.
Niacinamide has several specific effects on the scalp:
Strengthening the skin barrier
Niacinamide increases the production of ceramides in the skin. Ceramides are lipids that hold skin cells together and prevent moisture evaporation. A healthy barrier on the scalp means less irritation, less flaking, and a better environment for hair follicles.
Regulation of sebum production
An oily scalp and excessive sebum production can clog hair follicles and trigger inflammation. Niacinamide helps normalize sebum production, which for some people contributes to less follicular clogging.
Reduction of oxidative stress
Free radicals, caused by UV radiation, pollution, and stress, damage cells on the scalp and can weaken hair follicles. Niacinamide has antioxidant properties and protects cells from oxidative damage.
Influence on cellular aging
A study published in PMC showed that niacinamide lowers the protein expression of p16 and p21, two markers of cellular aging. Aged cells in the dermal papilla, the part of the hair follicle that drives growth, can slow down hair growth. Niacinamide appears to inhibit that aging.
Lowering DKK-1
DKK-1 is a protein that keeps the hair follicle in the resting phase and inhibits growth. Research shows that niacinamide lowers the expression of DKK-1 in human dermal papilla cells, which is theoretically beneficial for hair growth.
Does it really work for hair loss?
Here's where it gets honest. Because there's a nuance you won't find in many product descriptions.
A review article in the International Journal of Dermatology (2020) concluded that, based on existing evidence, topical niacinamide does not directly stimulate hair growth. The effects seen in laboratory settings do not automatically translate to clinically measurable hair growth in humans.
What we do have: a small-scale pilot study in which women with hair loss showed a statistically significant improvement in hair density and hair volume after six months of using a niacinamide preparation, measured by blind photo evaluation.
One small study, mainly on women. That's not ironclad evidence.
The honest conclusion: niacinamide is not an ingredient that on its own stops hair loss or significantly stimulates hair growth. But it does contribute to a healthier scalp, and that is not an insignificant factor.
The scalp as the foundation for hair growth
This is something that is often underestimated in discussions about hair loss. The focus is almost always on stopping DHT, activating hair follicles, or stimulating blood circulation. These things are important. But the condition of the scalp itself also plays a role.
An inflamed, dry, or oily scalp provides a poorer environment for hair growth. Ingredients that keep the scalp healthy, including niacinamide, are therefore useful as part of a broader approach.
They are not the components that solve everything, but they support the effectiveness of more active ingredients like Redensyl, Procapil, or caffeine.
Niacinamide in combination with other ingredients
Niacinamide works well with active hair growth ingredients:
Caffeine directly stimulates the hair follicle and inhibits DHT at a cellular level. Niacinamide supports the scalp on which caffeine acts.
Redensyl and Procapil activate hair follicle cells and extend the growth phase. Niacinamide reduces cellular aging and inflammation that can inhibit that activation.
Rosemary has proven anti-inflammatory effects on the scalp, similar to the role of but through different mechanisms.
Combination products that contain niacinamide alongside proven active ingredients are more useful than products that rely solely on niacinamide. The Hairborn Growth Serum combines a range of active ingredients with supporting components for a complete approach to hair loss.
How do you use niacinamide for your scalp?
If you use a serum or treatment with niacinamide, there are a few practical points to consider:
Apply it to a clean scalp. Dirt and sebum reduce the absorption of active ingredients. Preferably use it directly after washing.
Massage it in well. Not only for better absorption, but also for blood circulation in the scalp.
Use it consistently. One-time or sporadic use is of little help. Give it at least 8 to 12 weeks before forming an opinion.
Combine with a complete approach. Nutrition, sleep, and stress management also affect your scalp. Niacinamide is not a substitute for a healthy foundation.
Side effects
Niacinamide is generally well tolerated. Side effects are rare. Some people may experience mild irritation or redness at high concentrations during the first applications. This usually disappears on its own.
Do not confuse niacinamide with niacin (nicotinic acid). Niacin can cause a so-called flushing reaction, a temporary redness and sensation of warmth of the skin. Niacinamide does not cause this effect.
Conclusion
Niacinamide is not a miracle cure for hair loss. But it's not a useless ingredient either.
It strengthens the skin barrier, regulates sebum, inhibits cellular aging in the hair follicle, and reduces inflammation on the scalp. These are valuable contributions, especially as part of a serum that also contains active hair growth ingredients.
Anyone who buys niacinamide as a standalone solution with the expectation of visible hair growth in eight weeks will be disappointed. Anyone who sees it as a supportive part of a consistent routine is much closer to reality.