Do vitamins actually help your hair grow faster?

Short answer? They can, depending on the cause of your hair loss. Let us explain. “Vitamins and supplements can help with hair growth,” says Steve Daveluy, MD. That doesn’t mean it’s guaranteed, but “some help by making sure our hair follicles have all the nutrients they need to carry out the task of building and growing our hairs,” he says. “Others help by promoting the hair growth activities, similar to the way a medication may work.”

Elsewhere, others include ingredients that directly counteract certain triggers for hair loss, like hormonal imbalances, says Danilo Del Campo, MD, a board-certified dermatologist. For example, saw palmetto may target dihydrotestosterone (DHT), a hormone associated with hair loss, he says.

A lot of different vitamins – including B vitamins, vitamin D, and vitamin E – can improve hair retention and prevent shedding, according to Michele Green, MD, a board-certified cosmetic dermatologist. That said, in developed countries, it’s pretty rare to have hair loss caused by a vitamin deficiency, since you can often get all you need through a well-balanced diet. The exception is people on strict diets, like those who are vegan, she says.

That’s where the nuances come in. How much a vitamin or supplement helps with fast hair growth depends strongly on the underlying cause of your hair loss, Dr Green says. To that end, Dr. Daveluy recommends understanding your root causes of hair loss before turning to a vitamin or supplement. That way, you can take a targeted approach.

For people with actual vitamin deficiencies, taking supplements can yield strong results. But for those without nutritional deficiencies, or whose hair loss is due to non-nutrition related factors like genetics (or a separate medical condition), the benefits of hair growth vitamins and supplements “might be more modest,” Dr Del Campo says.

Also worth noting: while vitamins and supplements can help bolster your strands, they often are not effective enough on their own to fully grow and retain hair, Dr Green says. Some people, she explains, may need to add in other hair care treatment options alongside an over-the-counter vitamin or supplement to really decrease hair follicle miniaturisation and elevate hair growth and retention. This is where topical or oral medications, like Propecia and Minoxidil, may come into play. Dr Green suggests consulting with a board-certified dermatologist to get personalised recommendations.

Which vitamin deficiency causes hair loss?

Hair is protein, and in order to make protein, your body needs all the amino acids as well as vitamins, which are important coenzymes in protein synthesis, says Joyce Davis, MD, a board-certified cosmetic dermatologist.

Specifically, vitamin D helps stabilise the hair follicle, so not having enough of it can impact hair health. Vitamin D deficiency is really common, so for people worried about their hair health, Dr Davis recommends a vitamin D3 supplement as “pretty much essential.”

Iron deficiency and B12 deficiency can also impact your hair, Dr Davis adds, and so can too low levels of zinc, adds Dr Del Campo. On the flip side, having too much vitamin A as well as excess amounts of the mineral selenium can cause hair loss as well, according to Dr. Del Campo.

How to work out what vitamins and supplements you might need

“In terms of what supplements to take, it varies from person-to-person,” says Anabel. “Everyone’s diet is slightly different, as are health and gut absorption factors,” she adds. But we’ve rounded up some of the most common requirements below…

If you’re menstruating

“People who menstruate are likely to benefit from a supplement containing iron, vitamin C (which helps with iron absorption), L-lysine (which helps the body to store iron) and Vitamin B12,” says Anabel.

If your experience excessive hair shedding

“Iron and ferritin (stored iron) deficiency are one of the most common causes of excessive daily hair shedding in women,” says Anabel.

If you’re looking for something more general

“Vitamin D3 is another supplement ingredient everyone, including men, should look out for as Vitamin D deficiency is incredibly common, and it can impact hair growth cycling; every hair follicle has a Vitamin D receptor,” explains Anabel. However if you’re looking for one catch-all supplement, “for most people a general multi-vitamin is fine,” says Kate.

What to do before you take any vitamins or supplements

“Before taking supplements, it’s important to make sure you have a balanced diet, and if you’ve noticed hair loss or brittle hair, ask your GP, dermatologist, or trichologist to arrange a blood test to check for common nutritional deficiencies,” advises Kate Holden, consultant trichologist at Noughty Haircare.

Also, make sure the combination of vitamins you take don’t counteract or interrupt each other. “Some vitamins and minerals have an impact on each other so it’s important to be aware of this if you are targeting a specific vitamin or mineral,” says Kate. “For example, vitamin C can help to increase iron absorption, whereas zinc can inhibit iron absorption. Fat soluble vitamins are best absorbed with a meal containing fat, too, so timing can be important,” she says. Always check the instructions that come with your supplements, do your research and if you’re in any doubt, consult your GP.

What vitamins are good for thinning hair?

Water soluble vitamins

“Vitamin C and the B vitamins make up the water-soluble vitamins,” says Kate. “These are vitamins that we don’t store in the body, and any excess is washed out [when you pee]. This means that we need to consume them regularly, and that they are less likely to cause issues if taken in high doses. They aren’t inert though, and taking very high doses can lead to harmful side effects,” she warns. Plus if you take too much and you just pee it out, you’re wasting your money, so check the correct dosage for you.

Vitamin B

“B vitamins play a critical role in hair and skin health, as well as being necessary for the nervous system and in reducing the effect of stress on the body. B2 (riboflavin), B3 (niacin), B9 (folic acid) and B12 (cobalamin) are of particular importance as deficiency can result in anaemia leading to hair loss,” says Kate.

Vitamin B7 (Biotin)

Biotin helps the body metabolise proteins, fats and carbohydrates, converting food to energy,” explains Anabel. “It is important to note that Biotin deficiency is rare, and taking a pure Biotin supplement is not going to stop a hair loss issue, unless it’s due to a biotin deficiency,” she adds. Kate agrees noting “there’s limited evidence that supplementing above the recommended dietary allowance has any effect on improved hair and nail growth.” For those experiencing health problems or needing blood tests, biotin can interfere with some results (specifically thyroid tests and tests used to detect heart attacks) which is why it’s a good idea to tell your health provider you’re using it. But for most people, “as it is a water soluble vitamin, it shouldn’t cause any harm if you’d like to incorporate it into your routine,” says Kate. Foods rich in biotin include eggs, fish, meat, seeds, nuts, sweet potato, broccoli and cauliflower.

Vitamin B12 (cobalamin)

“Vitamin B12 helps your body metabolise amino acids (which are the building blocks of hair), and helps keep your red blood cells healthy, allowing them to supply adequate oxygen to your tissues, including your hair follicles,” explains Anabel.

Vitamin C

There are few studies that prove significant correlation between vitamin C and hair growth, however “vitamin C helps form red blood cells [which carry oxygen around the body] and this is needed for the absorption of iron,” explains Kate. Vitamin C also helps “maintain healthy skin and bones and helps with wound healing. It is also associated with protein metabolism, the synthesis of collagen and has antioxidant properties,” adds Kate. It also “contributes to collagen formation,” says Anabel.

“Vitamin C is the most easily destroyed of all vitamins, so we need to have a regular intake of vitamin C throughout the day. If you are trying to increase your iron or protein levels, vitamin C is really important,” Kate advises. Oranges and citrus fruits are rich in vitamin C.

Fat soluble vitamins

“Fat soluble vitamins are stored in our body tissue, which means that you need to be more careful with them as they can build up to a dangerous level. The fat soluble vitamins are A, D, E and K,” says Kate.

Vitamin D

“Vitamin D is thought to play a role in hair growth cycling, specifically in initiating the hair growth phase. Vitamin D deficiency is common in the UK, particularly during September to April as there isn’t enough ultraviolet light for us to produce our own, so it is recommended to supplement for vitamin D from autumn to spring,” says Kate. Alongside oral capsules, you can also boost your vitamin D intake through eating oily fish, red meat and egg yolks.

Vitamin E

“Vitamin E is an antioxidant that maintains skin health and supports our immune system. We know that oxidative stress, poor skin health and illness can have negative impacts on our hair, so vitamin E helps to support hair growth by ensuring a good environment for our hair follicles to thrive.” explains Kate.

Minerals

Iron

“Iron is essential for healthy hair, and iron deficiency is one of the most common causes of hair loss worldwide,” says Kate. “Women and people who are vegan or vegetarian are more likely to be iron deficient. Hair specialists and doctors will often check your iron levels as a priority if you have noticed hair loss and are in an at-risk group,” she adds. Good sources of iron include red meat, nuts and beans.

Zinc

Zinc is a crucial component in helping our bodies process protein and fats (the building blocks for healthy hair growth). You can keep zinc levels topped up every day through eating foods such as beef, lamb, crab, peanuts, wheat germ, milk and cheese.

Copper

“Copper contributes to the maintenance of normal hair colour,” says Anabel. In general, deficiencies in minerals like “iodine, zinc and copper can cause premature greying, poor hair growth and brittle hair,” says Kate.

Proteins

They might not technically be vitamins, but when it comes to hair growth it’s really important to flag the role of proteins. “It is possible to get all of the protein your body needs by eating a balanced diet,” says hair restoration surgeon and hair loss expert, Dr Bessam Farjo. “However, in today’s fast world, it probably does no harm to take certain supplements to be sure, especially if you believe you’re not eating a good balance,” he says. When we eat proteins, our bodies convert them into amino acids so that they can be useful to different parts of the body.

“I recommend taking a daily amino acid (protein) supplement,” concurs Anabel. “Hair is made of protein, and amino acids provide your strands with the building blocks that keep them strong. Our Philip Kingsley Density Amino Acid Protein Booster is made with pea protein, and contains an optimized blend of essential and non-essential proteins needed for optimal hair growth,” she adds.

L-Cysteine

“L-Cysteine is a sulphur-rich amino acid, found abundantly in keratin (the protein that makes up hair, skin and nails). Cysteine is instrumental in the formation of disulphide bonds – chemical bonds that hold your hair together,” says Anabel. Cysteine can be found in broccoli, Brussel sprouts, milk and yogurt.

Glycine

“Glycine is an amino acid that’s also vital to keratin formation and it contributes to collagen formation and hair strength,” says Dr Farjo. Glycine can be found in dairy products, spinach, beans, cabbage and bananas.

L-Methionine

L-Methionine is another sulphur-based essential amino acid. “Sulphur-rich amino acids are most important for your hair,” says Anabel.

What are the side effects of hair growth vitamins?

Some reassuring news: typically, there aren’t any side effects of taking vitamins or supplements for hair growth–so long as you consume them as directed, Dr Green says.

This means following dosing instructions so that you don’t ingest too much of a certain vitamin, which can lead to toxicity. Like we mentioned, having extra vitamin A and selenium can spur hair loss (literally the opposite effect you’re going for), and downing high doses of vitamin E can increase your chances of issues like hemorrhagic strokes, according to Dr Del Campo.

Additionally, some supplements, like saw palmetto, may interact with certain medications and cause harmful outcomes, he adds. As mentioned, biotin (vitamin B7)–which is involved in keratin production and widely advertised as a solution to hair loss–can interfere with some blood tests, including a thyroid test and one used to detect heart attacks, Dr Daveluy says. Experts are split on whether it’s actually effective in bolstering hair health. Dr Daveluy says if you do introduce a biotin supplement, be sure to tell all your health care providers.

When considering hair growth vitamins, Dr Del Campo urges people to first consult with a board-certified dermatologist and then to follow recommended dosages. It’s also important to do your own research to understand whether a product is safe and effective. “The best vitamins or supplements for hair growth will undergo clinical studies or market research to confirm whether they have been shown to increase hair growth,” Dr Green says.

A version of this article appeared on GLAMOUR US.