Niacin plays a major role in maintaining our health—so why have we never heard of it? Well, maybe you have. Niacin, aka vitamin B3, is a water-soluble nutritional element involved in neurotransmission and fatty acid synthesis, oxidation and reduction reactions, and one-carbon metabolism. Though niacin is a key player in keeping the body healthy, our bodies do not naturally produce it. That being said, niacin deficiency is typically rare, as we find it in many foods including red meat, poultry, and fish, as well as nuts, mushrooms, and avocado.
Niacin serves another purpose: assisting in healthy hair growth. It improves blood circulation, and therefore brings oxygen to the hair follicles, resulting in hair development. It's often recommended to those who have alopecia, with the goal of fuller, thicker hair.
We turned to dermatologist Brendan Camp, MD, and trichologist Shab Reslan to help further break down the benefits of niacin for hair.
Meet the Expert
- Brendan Camp, MD, is a double board-certified dermatologist specializing in medical and cosmetic dermatology at MDCS Dermatology in New York City.
- Shab Reslan is a certified trichologist and hairstylist based in New York City, specializing in hair growth and scalp health.
Scroll on to find out what our experts had to say about niacin for hair.
Niacin For Hair
Type of ingredient: Hydrator and anti-inflammatory
Main benefits: Increases blood flow to hair follicles to promote growth, improves the health of follicular cells, and keeps hair lustrous by maintaining sheen, body, and strength.
Who should use it: Generally speaking, anyone can use niacin in their diet as human bodies do not naturally produce it. Niacin for hair growth is typically used by those who are experiencing alopecia.
How often can you use it: According to Reslan, the recommended daily dose is 16 mg. She also notes that overdosing on some kinds of vitamin B can lead to complications such as inflammation of the skin and acne.
Works well with: As an antioxidant, vitamin B3 is fairly stable compared with other antioxidants on the market, Camp shares.
Don’t use with: Niacin should not be used with blood thinners, aspirin, blood pressure medications, cholesterol-lowering medications, and diabetes medications. Consult a doctor before adding niacin to your routine.
Benefits of Niacin for Hair
Niacin as a supplement can have multiple benefits for both the hair and scalp when properly dosed.
- Promotes blood circulation: Niacin is responsible for converting food into energy. "It’s necessary for healthy blood circulation which is crucial for optimal hair growth as it increases the delivery of oxygen and nutrients to the hair follicle," Reslan explains. Niacin's nutritional elements are also critical for maintaining cellular metabolism and cellular homeostasis.
- Supports scalp health: Reslan also shares that when used as a supplement, niacin can support a healthy scalp by balancing moisture and creating a protective layer that will enable healthy hair growth.
- Promotes hair growth: Niacin deficiency can impair the hair growth process, Reslan explains. This results in poor hair quality, but on the contrary, niacin can help promote hair growth and enable the process.
- Reduces scalp inflammation: "Nicotinamide has anti-inflammatory and hydrating benefits," Camp says. These properties help to calm and soothe the skin and scalp, reducing irritation and inflammation.
- Promotes thicker hair: "By improving the health of follicular cells, nicotinamide may help keep hair lustrous by maintaining its sheen, body, and strength," Camp says.
Hair Type Considerations
In general, niacin can be used with all hair types and textures. However, those battling alopecia issues have more of a reason to reach for niacin as a supplement than those who have healthy, full hair.
"Anyone can use niacin, but it will have the largest impact on those deficient in vitamin B3," Camp explains. "Because B3 is an essential nutrient the body can’t produce, it must be obtained from outside sources."
Breaking down specific hair types, those with dry hair, brittle, or damaged hair can benefit from the strengthening properties niacin provides, as well as the sheen. Thin hair can also benefit from niacin, as it promotes growth and strength. Additionally, because it is anti-inflammatory with hydrating properties, those with an inflamed scalp may also find it helpful.
How to Use Niacin for Hair
Intaking niacin can be as easy as eating a proper meal with meat and leafy greens or ingesting a daily vitamin. That being said, the ingredient is also found in daily hair products for those who need an extra boost.
Weighing the pros and cons of niacin, the experts recommend using supplements beyond daily food intake only when necessary. While niacin displays flashy benefits including healthier, thicker hair, it can also lead to negative side effects when taken at a higher dose. "Niacin should not be used in excess because the body does not store it and using too much or too high of a concentration of the product can cause skin irritation," Camp says.
You should consult with your doctor before adding niacin to your daily routine, and patch test any topical niacin products (as well as diet test any ingestible) when it comes to niacin supplements and treatments.
The Best Hair Products With Niacin
Camp shares that niacin can be found as an active ingredient in shampoos. "For shampoos with an active ingredient, it might be helpful to allow the lather to sit on the scalp skin for two to three minutes prior to rinsing to allow enough time for the product to enter the skin," he says. "Remember that you are treating the scalp skin, and not necessarily the hair shaft. If leaving the shampoo on your scalp for too long causes irritation, however, it should be rinsed off shortly after applying it." He recommends the Sunday Riley Clean Rinse Clarifying Scalp Serum with Niacinamide.
Nacin can also be found in scalp serums, Camp shares. He recommends the Bye-Bye Breakage Strengthening + Thickening Scalp Serum by Ouidad. Using only one to two drops in each section of the hair, it is recommended you massage the product into the scalp and leave it on, with no rinse out after.
Camp says that leave-in treatments are also a solid topical niacin option. He recommends Dove's Dry Scalp Care Leave-On Treatment, which helps soothe scalp dryness and smooth the hair. In spray form, this leave-in treatment is easy-to-use and should be placed on damp hair and massaged into the scalp.
Does niacin have side effects?
A common side effect of niacin is flushing. This flushing can be in the form of redness or in warmth of the skin. It can sometimes be accompanied by tingling or itching. The onset of flushing can occur rapidly but typically only lasts around an hour.
Are niacin and biotin the same?
No. While niacin (vitamin B3) and biotin (vitamin B7) may have similar objectives for hair strengthening and growth, they are not the same. They are, however, both soluble B-vitamins found naturally in some foods.
Does niacin help your scalp?
Niacin can support a healthy scalp by balancing moisture and creating a protective layer that will enable healthy hair growth, according to Reslan.
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