The Complicated Answer Behind Whether Hair-Growth Vitamins Actually Work

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Strong, shiny, and beautiful hair is seen by many as a sign of youth and vitality. It is also a cultural symbol of health and wellness the world over. With this symbolic weight, it isn't any wonder that the hair-growth vitamin market is part of a 3.5 billion dollar industry.

Hair-growth supplement companies aggressively market the incredible growth and strengthening properties of their products. These seemingly magic pills are touted as the cure to a number of hair problems, from excessive thinning to weak and brittle strands. Many claim to treat hair loss as well. But do they actually work? The answer lies somewhere in the gray area between 'yes' and 'not really.' While hair-growth vitamins may be helpful for individuals suffering from particular vitamin deficiencies, an estimated 99 percent of these products don't actually work for the average person. This makes it unlikely for a relatively healthy person to see an improvement in volume, texture, or length even after a few months of a hair-growth vitamin regimen. "Not all types of hair loss are the same, and the treatment will be different depending on the type," dermatologist Dr. Erin Hodges tells Tryon Medical Partners. "Everyone will get the most common type of hair loss at some point. It just depends when and to what extent.

So, before you click on that too-good-to-be-true Instagram ad and start adding vitamins to your cart, read on to determine if you might benefit from hair-growth vitamins or not.

It seems safe to reason that if hair-growth vitamins worked as well as they claim to, we would all be sporting luscious, Rapunzel-like locks. Regrettably, that isn't the case. There are currently no clinical studies that have determined the effectiveness of hair-growth supplements for average, healthy people. This is mainly because hair health is largely determined by a person's age, hormones, and genetics rather than the addition of vitamins to the body.

Due to the lack of conclusive data to support the claims of hair-growth vitamins, many skin and medical experts disregard their efficacy. "I don't believe in any of the hair supplements that are out there," board-certified dermatologist Dr. Rick Mizuguchi tells Byrdie. Dr. Pieter Cohen, dietary supplement expert and associate professor of medicine at Harvard Medical School, agrees, telling Consumer Reports, "I'm not aware of any robust data suggesting that any supplements can treat natural, aging-related hair loss or nail damage, or give you healthier skin." However, some anecdotal evidence suggests that ingestible hair-growth vitamins are useful for people suffering from thinning hair, bald spots, or excessive breakage, and many men and women swear by them, claiming they saved their hair. 

If you choose to take hair-growth vitamins, they are generally thought to be safe, but it will take time for them to work, if they do at all. If you have no underlying hormone or medical conditions, and you take the supplements consistently, you may see improvements within two to six months.

Hair loss has many causes, with iron deficiency being one of them. Roughly 10 million people in the United States are iron deficient, meaning their bodies do not produce enough iron and therefore do not produce enough hemoglobin. This affects the amount of oxygen that gets carried to the cells of the body, including those that stimulate hair growth. Hair loss with an iron deficiency often results in male or female pattern baldness, with increased hair shedding being the first sign that low iron levels are affecting hair health. Luckily, iron deficiency and the hair loss it causes are reversible.

"Iron is really important for hair growth and hair health," dermatologist Melissa Piliang, MD tells Cleveland Clinic. "When we see patients who are experiencing hair loss, we often perform labs to screen for iron deficiency. It's not uncommon for us to find iron to be low in women."

Iron supplements are safe and effective at addressing low iron levels, and therefore reversing your hair loss, but they may cause constipation, nausea, and stomach cramps. Therefore, eating a diet with iron-rich foods is an often preferred way to increase your iron levels. "Many women avoid red meat, which is our best source of iron," Dr. Piliang explains. "If you're a meat eater, the best way to address this problem is to get two 4-ounce portions of red meat per week. This small amount should be enough to maintain healthy levels of iron for most women."

Vitamin D deficiencies are common in the U.S., with roughly 41% of adults failing to consume an adequate amount via sun exposure or diet. While an adequate amount of vitamin D is vital for the functioning of a proper immune system and bone health, a lack of it is also linked to weak hair, shedding, and conditions like alopecia. "Vitamin D is metabolized in the skin by keratinocytes, skin cells that produce keratin," Dr. Green tells Forbes Health. "When the body does not have enough vitamin D, the keratinocytes in hair follicles have trouble facilitating hair growth, resulting in shedding and hair loss." If you are lacking in vitamin D, supplementation between 5,000 to 10,000 IU per day, in addition to vitamin D-rich foods, can help strengthen and grow your hair.

Vitamin E is a fat-soluble vitamin that acts as an antioxidant. It combats free radicals that damage hair follicle cells and is therefore thought to support a healthy scalp and hair. "Depending on its purity and source, vitamin E can be great for reducing free radicals, improving collagen, and reducing oxidative stress in the scalp which in turn enhances hair growth," certified trichologist William Gaunitz tells mbg lifestyle. However, some small studies suggest that vitamin E supplements may have negative health effects. "They can interfere with other medications you are taking," Dr. Kiran Sethi tells Vogue India. "Plus, studies with Vitamin E for hair, skin, and nails have not proven benefits."

It is normally recommended that pregnant women take prenatal vitamins to lower the risk of nutrient deficiencies, birth complications, and congenital disorders like spina bifida. These multivitamins are packed with vitamins A, C, and E, plus zinc, iron, iodine, and B vitamins, all of which are needed to make your skin, nails, and hair happy. While these vitamins are needed to support new life, some believe they produce the positive side effects of pregnancy such as glowing skin and beautiful hair. However, these are more likely the result of hormone changes. "The prevailing wisdom is that hair grows so nicely during pregnancy because women are making a lot of the estrogen hormone," Dr. Mary Jane Minkin, clinical professor of obstetrics and gynecology at Yale Medical School, tells Women's Health.

Some women think that taking prenatal vitamins, even if they aren't pregnant, can help them achieve the flowing locks of their dreams. Unfortunately, this "solution" is likely to cause more problems than it solves. "It has long been believed that prenatal vitamins lead to longer, healthier, and thicker hair in women, even if they are not pregnant," Anna Chacon, MD, FAAD tells Vegamour. "... In general, prenatal vitamins won't help significantly unless you are deficient in those specific vitamins which provide nutrition to the hair follicle."

But what happens if you don't have a vitamin deficiency and you're still experiencing hair changes? If you can't outrun your genetics, and taking a hair-growth vitamin is probably not going to prove effective, how do you go about growing strong, healthy hair? This answer, thankfully, is simple: eat a balanced, nutritious diet.

What you eat and your body's overall nutrition are the most important factors in growing strong hair. While vitamins and supplements can assist with any gaps that a nutritious diet may leave, eating nutrient-dense food rich in iron, vitamins B, C, and D are more likely to get you the results you want. A hair-healthy diet can include foods like berries, leafy green vegetables, Greek yogurt, eggs, fatty fish, tofu, chickpeas, and whole grains.

"Eating for optimal health and healthy hair go hand-in-hand," nutrition and wellness expert Samantha Cassetty, MD, RD tells Shape. "In both cases, getting sufficient protein while also focusing on wholesome plant foods will help ensure that you get the nutrients, antioxidants, and anti-inflammatory compounds tied to healthier hair."