Do Hair Growth Supplements Work? Expert Review And Analysis

Reading time: 10 min.

Medically reviewed by
Dr Peter Barron (GMC) — Updated on February 27, 2026

Are you considering hair growth supplements to help combat hair shedding or thinning? If you’re experiencing these symptoms, you’re not alone. There are many types of hair loss, and the most common is androgenetic alopecia, which affects around 50% of men and women by the age of 50 [1].

Hair growth supplements are often marketed as a solution for those experiencing hair loss or seeking healthier hair. These products — packed with vitamins for hair growth, minerals, and other nutrients — claim to support hair health and promote growth. However, the effectiveness of these supplements remains debatable, as scientific evidence supporting their benefits is limited and often inconclusive.

A full, healthy head of hair can have a big impact on your appearance and self-confidence, and we’re here to guide you through the best options available. Whether you’re considering supplements as a standalone therapy or as a complement to other hair loss treatments, we have the information you need to make an informed decision. In this article, we’ll explore:

Why hair growth supplements are so popular
Possible ways these products may work
Common ingredients in hair growth supplements

Table of Contents

What are hair growth supplements?
Possible ways hair growth supplements may work
Why are hair growth supplements so popular?
Common ingredients in hair growth supplements
Getting evidence-based treatment for hair loss

What are hair growth supplements?

Hair growth supplements (such as Hair Gain Capsules) are products that aim to boost hair health and stimulate growth. They typically contain a mixture of vitamins, minerals, and natural extracts. These supplements can come in many different forms, including:

Tablets and capsules
Hair gummies
Powders
Liquids
Topical solutions
Sprays

The industry is booming, but hair specialists remain sceptical. While some people report positive results, more research is needed to determine whether hair growth supplements live up to their bold claims.

Possible ways hair growth supplements may work

Hair growth supplements are marketed to improve hair breakage, thinning and shedding. However, when placed under the microscope, these claims are rarely backed by sufficient evidence.

Supplements do not fall under the reviewing scope of the Food and Drug Administration (FDA). The Food and Drug Administration (FDA) does not approve dietary supplements for any purpose [2]. While the FDA acknowledges that some supplements can improve your general health, they emphasise that nutritional supplements can also have health risks, interact with medications, or interfere with lab tests [2].

While the FDA regulates dietary supplements, it does not generally review them before they are sold to consumers. In many cases, companies can produce and sell dietary supplements without even notifying the FDA [2].

While some vitamin and mineral deficiencies have proven links to hair loss [3], little evidence suggests supplements can help your lost hair regrow. Here are some of the ways that supplements may possibly improve hair growth.

Correcting nutrient deficiencies

Nutrient deficiencies can damage your hair structure and prevent healthy hair growth, and some vitamin deficiencies can cause hair loss. For example, inadequate protein intake can lead to acute telogen effluvium [4], and niacin (vitamin B3) deficiency can cause diffuse thinning [1]. However, most nutrient deficiencies are uncommon in the developed world and experts advise dietary changes, such as eating a balanced diet for healthy hair, are likely to be more effective than supplements.

When discussing supplements, Teresa Fung, an adjunct professor of nutrition at the Harvard T.H. Chan School of Public Health, says:

“If you’re generally healthy and eat a varied diet, there’s just no need. A vitamin pill does not contain all the beneficial stuff in food. It’s not a shortcut” [5].

There are also potential links between nutrient deficiencies and male or female pattern hair loss, chronic telogen effluvium, and alopecia areata [1]. Hair growth supplements aim to address low levels of these nutrients so your body can produce strong, healthy hair. However, there is little evidence to suggest these supplements actually help your hair regrow.

Improving hair follicle health

Vitamins and minerals play an important, although not entirely clear, role in normal hair follicle functioning [3]. For example, folate and vitamin B12 are important for making nucleic acids, which are essential for cell growth and division [3].

Boosting blood circulation

Certain ingredients found in hair growth supplements, such as ginseng [6], may improve blood circulation. Improved blood flow to the scalp means that hair follicles receive more oxygen and nutrients, which may, in theory, promote healthier hair growth and reduce thinning [7].

Multiple studies claim that ginseng promotes hair growth, but on inspection, most have been conducted on mice or isolated human hair follicles in laboratory conditions. Further research on humans is needed to confirm this claim.

Ashwagandha is sometimes known as Indian ginseng, but it’s not true ginseng. Research is conflicted as to whether ashwagandha helps with hair health, so make sure the supplements you’re using are suitable.

Optimising hormone levels

Some hair growth supplements include ingredients like saw palmetto for hair loss, which has been used to successfully treat androgenetic alopecia [8]. Dihydrotestosterone (DHT) binds to androgen receptors in men’s hair follicles, leading to hair loss when there are excessively high levels of DHT in their bodies.

Research suggests saw palmetto can help prevent the conversion of testosterone into DHT [9], reducing hair shedding and promoting hair regrowth and scalp appearance in people with male pattern baldness [9].

Protecting against free radicals

Vitamins C and E are natural antioxidants [10] that protect hair follicles from damage caused by free radicals [11]. These nutrients help reduce and neutralise free radicals, which contribute to the ageing process [11].

In hair, this manifests as greying, reduced growth and shedding, so maintaining healthy levels of these nutrients may help to improve hair health. However, there is currently a lack of evidence to show that supplementing with vitamin C for hair or vitamin E for hair improves the condition of your locks.

Supporting keratinisation

Vitamins C and E play an important role in keratinisation [10]. Keratinisation is the process of filling hair cells with keratin — a tough, protective protein. Certain nutrients, including vitamins E and C, are vital to support this process [10].

Keratinisation helps form a barrier to protect your hair from the environment, strengthening it, preventing dry, brittle hair and reducing hair loss. But, again, further research is needed to prove that supplementing with these vitamins can help your hair.

Improving general health

Finally, hair growth supplements often contain vitamins and minerals that support your general health. A healthy body is more likely to produce healthy hair, so these supplements may indirectly contribute to better hair growth by improving your general well-being.

Why are hair growth supplements so popular?

The hair supplement industry has exploded in recent years. Research shows the use of supplements for hair, skin, and nails nearly doubled from 2011-2012 to 2017-2020 [12].

However, there is limited evidence to support the use of these supplements, and they have numerous safety concerns, including a lack of warning labels, nutrient overdosing, and quality issues [12]. So, why does the hair supplement trend continue to grow?

Marketing and celebrity endorsements

Celebrities and social media influencers promote hair growth supplements, which may be a driving force for their popularity [12]. Many supplements promise thicker, longer hair, often backed by high-profile endorsements. This creates the perception that these products are a miracle solution despite the lack of solid research supporting their use.

Teens and young adults increasingly use Instagram for health information [13]. One study evaluated 100 Instagram posts about skin, hair, and nail supplements and found that only 1% of posts contained a visible supplement facts label [13].

Emotional stress

Hair loss can be an emotionally distressing experience [14], leading many people to seek quick fixes. In addition, stress can cause hair loss or worsen existing symptoms. An easy, pill-based solution can be attractive, even if the benefits are uncertain. The stress of hair loss combined with the wish for an easy cure may make people more likely to believe supplement companies’ claims.

Possible placebo effect

Some people report positive results after taking hair growth supplements, but these results may be due to the placebo effect rather than the ingredients. When people believe they are taking something that will help, they may perceive an improvement, even if the supplement has no real impact.

Interestingly, research suggests a placebo treatment can improve symptoms such as pain, depression, and anxiety, even when the person knows they are taking a placebo [15]. This shows the power of the placebo effect.

Natural appeal

There is a growing preference for natural and holistic approaches to health, and supplements fit neatly into this trend. The idea of boosting hair growth with vitamins and minerals seems appealing and harmless, even if it lacks scientific evidence.

Common ingredients in hair growth supplements

Healthy hair growth relies on a variety of vitamins and minerals to keep your hair and scalp in top condition. These are found naturally in your body, and avoiding deficiencies can help to prevent hair loss.

Further studies are required to determine whether these nutrients improve hair health when taken as a supplement. Here are some of the most important vitamins, minerals, and fats for your hair:

Vitamin A

Vitamin A is essential for cell growth, including hair cells [16], but it’s important to maintain balanced levels. Too much vitamin A can cause hair loss and reduced sebum production [16], an oily substance that keeps your scalp moisturised and hair healthy. More research is needed to determine whether vitamin A supplementation can improve hair growth in people with a deficiency.

Vitamin C

Vitamin C is a powerful antioxidant that helps protect hair follicles from damage by free radicals. It also supports the production of collagen [17], a protein that strengthens hair, and improves the absorption of iron [18], which is vital for healthy hair growth. Again, there is limited research on whether vitamin C supplementation can improve hair growth.

Recommended

Does Collagen Help Hair Growth?

Vitamin D

Vitamin D plays a role in creating new hair follicles [19] and maintaining healthy hair cycles [20]. Vitamin D deficiency has been linked to several types of alopecia, including telogen effluvium, androgenetic alopecia, alopecia areata, trichotillomania, and scarring alopecia. Sufficient vitamin D levels prevent hair loss from these conditions and encourage hair growth.

Vitamin D is one of the few vitamins for which deficiency is common, especially in countries like the UK, where sunlight is limited in the winter. One study analysed data from 397,737 people in the UK Biobank. It found the majority of participants had either vitamin D deficiency (21.1%) or vitamin D insufficiency (34.4%) [21]. However, there is a lack of conclusive evidence to support supplementing with vitamin D as a treatment for hair loss [20].

Vitamin E

As an antioxidant, vitamin E supports healthy hair growth by reducing oxidative stress [22]. Oxidative stress happens when your body has more free radicals than antioxidants can manage, causing damage to cells throughout your body, including your hair cells.

In theory, you can reduce this damage by maintaining healthy levels of antioxidants, such as vitamins E and C. However, further research is needed to determine whether vitamin E or C supplements can improve hair growth or reverse hair loss.

Biotin (Vitamin B7)

Biotin is one of the most well-known vitamins for hair health. This nutrient supports the production of keratin [23], the main protein that makes up hair, skin, and nails. Adequate biotin levels can improve hair strength and reduce breakage [7],. which is why the best biotin for hair growth continues to gain popularity.

However, research only supports supplementing with biotin if you have a known deficiency [24]. In addition, biotin supplements can influence results from thyroid and reproductive, cardiac, and immunosuppressive medical tests [25]. This can be dangerous if it leads to incorrect medical treatment.

Iron

Iron is vital for hair growth as it helps make red blood cells, which carry oxygen to hair follicles. Iron deficiency, which can lead to anaemia and hair loss, is the most common micronutrient deficiency worldwide [26]. Over 20% of women experience it during their reproductive lives [26].

However, iron supplements may cause gastrointestinal side effects [26]. Research also cautions against unsupervised iron supplementation, which can cause toxicity and potentially severe side effects [1]. There is limited research into iron supplementation to boost hair growth. Learn how long it takes for iron tablets to stop hair loss.

Many other ingredients are often found in hair growth supplements and probiotics for hair. These include:

Niacin (Vitamin B3)
Folic Acid for hair growth (Vitamin B9)
Pantothenic Acid (Vitamin B5)
Zinc for hair loss
Selenium for your hair
Magnesium to prevent hair loss
Omega-3 for your hair
Collagen
Keratin
Saw Palmetto
Horsetail Extract
Ginseng
MSM for hair growth (methylsulfonylmethane)
Silica

Getting evidence-based treatment for hair loss

If you’re experiencing the first signs of hair thinning and balding, the best way to get evidence-based advice and treatment is to consult a trichologist. Hair doctors at the Wimpole Clinic have a variety of diagnostic trichology tests at their fingertips and can recommend science-backed solutions for your hair loss.

Suggested treatments for your symptoms may include natural remedies for hair loss, medications such as minoxidil or finasteride, low-level laser therapy for hair loss, and red light therapy for hair growth. You may also be a candidate for a hair transplant, which can provide a long-term solution because a hair transplant is permanent. Book a consultation at one of our clinic locations to get a diagnosis and learn more about treatment options.