The 14 Best Hair Vitamins, According to Thousands of Customer Reviews

If you've ever dealt with dry, brittle, frizzy, or broken hair then you know how frustrating it can be to sift through every deep conditioner and cream on the market in the hopes of finding one that will finally work. But what if the problem isn't actually on the surface of your hair?

According to Lisa Moskovitz, RD, CDN, and CEO of New York Nutrition Group, "What you put inside your body can influence what you see on the outside of your body." Aka, the vitamins and minerals you get from food — or the lack thereof — can contribute to hair loss and breakage.

"Key nutrients to highlight for hair health include iron, zinc, selenium, protein (amino acids), anti-inflammatory fats like olive oil and avocado, as well as antioxidants," she tells InStyle. "All of these health-promoting vitamins, minerals, and food groups can promote healthy hair and help strengthen hair, improve hair growth, and prevent hair loss."

This is where hair supplements come in. "Supplements can help fill in the gaps in your diet to prevent nutritional deficiencies that can weaken hair and interfere with the natural hair growth cycle," says Moskovitz.

However, she strongly suggests seeing a nutritionist or doctor to pinpoint deficiencies before taking any tablets. "Unless you have a known deficiency, a supplement may not be warranted and can possibly do more harm. For example, vitamin A in excess can actually contribute to hair havoc." Moskovitz recommends having a blood test performed which can "detect iron deficiencies, thyroid abnormalities, hormonal imbalances, and other nutrient deficiencies that can contribute to hair loss, brittle hair, or hair that just looks unhealthy," she says. "Using that data, you can determine what might be the best option based on your individual history and areas of concern."

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Once you know which vitamins to look for, it’s time to get shopping. To help you find the best supplement to fit your needs, we turned to real reviews from customers who have bought and used these hair vitamins for themselves. Keep reading to see which 14 vitamins for hair they say will give you the locks of your dreams.