You are currently viewing Top Three Supplements for Promoting Hair Growth, as Recommended by a Functional Medicine Practitioner.

Top Three Supplements for Promoting Hair Growth, as Recommended by a Functional Medicine Practitioner.

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  • Post last modified:September 26, 2023

Hair Health Hotline

Hair Health Hotline provides direct access to dermatologists, trichologists, hairstylists, and other beauty professionals. Each story in this series addresses a common concern related to hair or scalp and offers scientifically supported solutions to care for your strands.

Many individuals swear by an “inside out” approach to beauty, focusing not only on the creams they apply externally but also on their dietary intake. The idea is that maintaining the right balance of nutrients and consuming them in proper amounts will ensure the proper functioning of all bodily systems (such as digestion, metabolism, and immunity), ultimately reflecting in the health and appearance of your hair, skin, and nails.

If you have ever compared the numerous supplements available in the market, you are aware of the long and overwhelming list of nutrients reportedly involved in hair growth. To help you navigate through this information overload, Elizabeth Boham, M.D., M.S., R.D., a functional medicine physician and medical director of the UltraWellness Center, breaks down the most beneficial supplements for hair growth.

Q: My hair is not as thick and full as it used to be. Is there a supplement for hair growth that can assist?

A: If your diet lacks specific nutrients and this is causing your hair to thin, taking supplements that address your deficiencies may help restore healthy growth.

However, it is important to avoid randomly selecting any daily multivitamin off the shelf. Experts recommend adopting a more targeted approach. Before starting any supplementation, make sure to consult your healthcare provider for the necessary blood tests or other evaluations required to identify the ideal hair growth supplement for you.

How Nutritional Deficiencies Can Impact Hair Growth

If you are experiencing hair loss or thinning, your diet may be partially or entirely responsible. According to Dr. Boham, “Often, multiple factors contribute to a person’s health and hair growth, and nutrition is a common element.” When individuals seek assistance for hair loss, nutritional deficiencies are frequently identified during testing. Dr. Boham explains, “I would estimate that at least half the time, nutrition deficiencies are contributing to hair loss.” This is where supplements come into play.

Courtesy of Elizabeth W. Boham

Best Supplements for Hair Growth and Thickness

Dr. Boham identifies iron, protein, and biotin as three key nutrients that commonly influence hair growth. These nutrients can affect the number of hair strands, their thickness, or both. “A deficiency in biotin and amino acids particularly impacts hair thickness, brittleness, and overall quality,” she explains.

  • Iron and amino acids have a tendency to influence the quantity of hair, the magnitude of hair loss.

Iron for Hair Growth

Firstly, iron is a crucial mineral that your body requires to produce specific proteins and hormones. “Iron is the nutrient that most commonly affects hair growth and causes the most significant change,” says Dr. Boham. While experts don’t completely understand the role that iron plays in hair wellness, one hypothesis is that when your body has a low iron supply, it redirects iron stored in your hair follicles elsewhere, resulting in weaker hair.

Individuals who menstruate — particularly those with a heavy flow — often experience low iron levels during menstruation, and some individuals simply don’t absorb iron effectively, says Dr. Boham. Moreover, if you follow a vegetarian or vegan diet, it’s more challenging (though not impossible) to maintain adequate iron levels since your body doesn’t absorb iron from plant sources like beans, legumes, and spinach as readily as it does iron from animal proteins.

Protein for Hair Growth

Protein doesn’t just have a role in post-workout recovery; it also provides structure to your hair. Both protein and amino acids (the building blocks of protein) can serve as beneficial supplements for hair growth in individuals who don’t consume enough dietary protein, according to Dr. Boham.

“Protein deficiency is more prevalent in individuals who are restricting their diet for various reasons, are vegetarians or vegans, are older and consuming fewer calories, or have digestive issues such as SIBO (small intestinal bacterial overgrowth),” says Dr. Boham. When hair loss is attributed to these factors, “I often provide amino acid supplementation to facilitate hair regrowth, and it yields excellent results,” she states.

Biotin for Hair Strength

If you’ve ever explored “hair, skin, and nail” supplements, then you likely anticipated this recommendation. Biotin, also known as vitamin B7, is vital for maintaining metabolic health, nervous system functions, and the strength of your hair, skin, and nails.

It is widely recognized that biotin impacts the condition of hair,” states Dr. Boham. “Individuals with insufficient levels of biotin will experience coarser hair, fragile hair, and hair damage.

However, biotin insufficiencies are less prevalent than the promotional campaigns for supplementation may lead you to believe. “Biotin is not as common of a insufficiency as iron or the amino acids,” says Dr. Boham. Anecdotally some people have reported enhanced hair growth from taking biotin in the absence of an insufficiency, but biotin doesn’t necessarily benefit those who aren’t lacking in the vitamin, she explains.

Strive to Obtain Essential Nutrients From Food

Ideally, you’ll obtain enough of these and other nutrients your body requires through food, eliminating the need for hair growth supplements, says Dr. Boham. “Diet is always optimal,” since you’re less likely to experience toxicity (taking in too much of any given nutrient) that way, she says. “But if you’re working with [a healthcare provider] who can test your levels and know exactly what you need, supplementation can truly be effective when diet alone doesn’t work,” she says. Know that “it’s really good to have a targeted approach to supplementation so you know what you’re taking and for what reason.” Consider consulting a nutritionist or medical professional who “can do an assessment of your diet and nutritional status because that can help you know exactly what to take,” and how much, says Dr. Boham.

How Much Hair Growth Supplement Should You Add?

That said, it’s generally safe to include more protein to your diet if you take inventory of your eating habits and realize you’re failing to meet the daily recommended amount. Generally, one gram of protein per day per kilogram of your bodyweight suffices, says Dr. Boham. The Academy of Nutrition and Dietetics recommends 5.5 to 6.5 ounces of protein per day for most adults “There are numerous different protein supplements out there from collagen to pea protein and individuals will notice a difference,” she says. “And the amino acid supplements are the breakdown products of the protein. If it’s a blend of amino acids most people tolerate it pretty well.”

With iron, though, you don’t want to intervene on your own, says Dr. Boham. It’s crucial to have your iron levels checked through bloodwork to find out where you stand since excess iron can cause tissue damage and organ failure.

Consider a Specific Approach

Choosing a supplement for hair growth with a mixture or combination of ingredients may not be as helpful as a more targeted approach, according to Dr. Boham, so you may want to decide against a daily multi-vitamin if hair regrowth or health is your specific goal.

For hair growth (and overall health), iron, protein, and biotin are your allies. If you are not getting enough of one of them through your diet, supplements may play a significant role in your plan for hair regrowth.

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