Hair loss can have many causes—from mounting stress, to genetics, child birth, and more—but in addition to a well-rounded diet, the best hair growth vitamins contain ingredients, like Omega-fatty acids and vitamins, to help fortify weak or damaged hair. And while fortified shampoos or scalp oils may stimulate hair at the surface, ingesting a vitamin provides your body with the right nutrient balance for optimal growth. “Our scalps and strands have independent biological makeup and daily stressors, requiring an individualized approach,” board-certified dermatologist Chesahna Kindred previously told Bazaar.

What are the best hair growth nutrients?

• MSM. Since your hair and nails are primarily made of keratin, the compound MSM (or methylsulfonylmethane) is an especially ideal ingredient to help improve the appearance and feel of hair, as it helps your body maintain it.

• Essential fatty acids. “To help with dry skin and scalp, essential fatty acids found in avocado and oily fish, like salmon, are helpful. In vitamin form you are looking for Omega-3 rather than 6 or 9,” says Grow Gorgeous partner trichologist Stephanie Sey.
• Vitamins A, C, D, and E. In addition to MSM and Omega-3 acids, ingredients like vitamins A, C and E, saw palmetto, ashwagandha, hydrolyzed collagen, biotin, keratin, and magnesium can also be helpful in the regrowth process. While some vitamins can be useful to those in need of extra nutrients to encourage scalp health and hair growth, professionals advise that your body will naturally eliminate excess nutrients it doesn’t actually need.

“Vitamins usually only work if there is a deficiency in the first instance,” Sey says. “If the body is balanced, then those surplus vitamins are not useful, and in the case of water soluble vitamins like biotin the excess comes out in your urine. Ideally, it is best to get your vitamins from your food. if I had to recommend a key ingredient for overall hair health, I would say Vitamin D,” she advises. “Most people are deficient, and it’s important for many vital functions within the body.”

Why does hair start thinning?

Sey tells BAZAAR.com that androgenetic (also known as male or female pattern) and telogen effluvium hair conditions are most commonly experienced, though loss often starts with general thinning. “Telogen effluvium is when you shed larger amounts of hair because your body has been shocked into moving your hair from the anagen or ‘growth phase’ to the ‘telogen’ resting phase, which causes excessive hair shedding,” she explains. “Usually the shock can be cause by high grade fever, childbirth, surgery, or emotional distress.”

Although the right growth vitamins can help mitigate hair loss with continued use, professionals advise speaking with an expert to find out the true root cause to prevent more thinning in the long run. “While someone might care about restoring their hair to its former luster and thickness, the cause of thinning ultimately determines the best method of treatment,” says certified aesthetics, hair transplant, and restoration treatment physician at Eternal Hair and Esthetics Ednan Sheikh. If you’re unsure what’s causing your hair thinning, Sheikh advises consulting an expert to determine the origin of hair loss, and collaborate on a solution that works best for your needs.

To help you narrow down a new favorite, we’ve rounded up the best hair growth vitamins and formulas shoppers and experts and swear by for increased thickness and growth.

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