If you’ve attempted to find a solution for broken nails, split ends, and dull skin, there’s a good chance you’ve stumbled across biotin as a holy-grail product. Highly marketed as a “miracle” vitamin, it’s on the shelves at pretty much every beauty and health retailer. But no matter how many glowing reviews a product receives, it’s always a good idea to get the opinion of a health expert. I did just that by reaching out to a doctor who focuses primarily on holistic health. Read on to find out which biotin supplements are doctor recommended and which ones are taking over the internet with glowing reviews

Biotin (also known as B7 or vitamin H and sometimes even referred to as coenzyme R) is one of the water-soluble B-vitamins within B-complexes and sometimes multivitamins. It’s found in a variety of food sources including egg yolks, salmon, mushrooms, and spinach but also produced in our bodies. It’s not an essential vitamin, but because it’s water-soluble, our bodies cannot hold large amounts of biotin internally, and it can’t stay in the body long, so it’s best to supplement it daily.

“Biotin increases the strength of hair strands, as it simulates keratin production, which can increase the rate of hair follicle growth,” explains Lana Butner, a naturopathic doctor serving NYC and the surrounding areas. “B7 increases the strength of nail matrices, decreasing the occurrence of brittle nails and frequency of your fingernails splitting.” To see a major impact on the hair and nails, Butner recommends supplementing for at least four to six months (5000 micrograms per day). It’s also helpful for individuals with diabetic symptoms, such as neuropathic pain. 

For some users, the vitamin is not without its drawbacks. “Biotin can have some interactions with various thyroid markers on bloodwork, making thyroid stimulating hormone (TSH) appear falsely decreased and free T4 and free T3 falsely elevated,” shares Butner. However, other than thyroid interaction on bloodwork, supplementing with biotin is relatively benign. Butner favors biotin supplements with 5000 micrograms up to 10,000 micrograms per capsule. Some of her favorites include Pure Encapsulations Biotin 8mg, Vital Nutrients Biotin 10mg, and the Allergy Research Group HiBiotin.

A five-star review of this product on Amazon reads, “I have been taking for a few weeks and I really can tell the difference with my skin and complexion. I also feel healthier and notice when I do not take it.”

“I swear by this. My hair would never seem to grow until I tried this product,” one five-star review for Nature’s Bounty Biotin supplement reads. “The 10,000 is what your hair needs in order to see the difference in growth. The quality and price cannot be beat.”

“One of the things I like about these tablets is that they are easy to swallow and do not have any unpleasant taste. I also appreciate that they are vegetarian and free from common allergens such as gluten, soy, and dairy,” a reviewer writes. “After taking these tablets for a few weeks, I have noticed that my hair feels thicker and healthier, and my nails are stronger and less prone to breaking. My skin also feels smoother and more radiant.”

“I was taking this product last year and discontinued using. I could see a noticeable difference and quickly purchased over amazon and began using it again,” says one glowing review. “It leaves my skin almost impeccable and with an aura/glow about it that is difficult to describe. I absolutely love biotin and will never stop using it again.”

A five-star review for Sports Research’s Extra Strength Vegan Biotin says, “I have tried every vitamin and topical hair care product for hair growth you can think of, and this has been the only thing that I’ve actually seen results. My hair normally only grew an inch or two each year. Since using this my hair has grown about 4 inches within a year!”

One reviewer writes of Thorne’s Biotin-8, “After going through chemo twice since 2015, my fingernails have never recovered and have been badly cracked and painful for more than 7 years. Have tried various products to try to strengthen them but nothing worked like this!”

“After taking for just over a month, I do see some improvement in my skin and nails. I will definitely keep taking this going forward.After taking for just over a month, I do see some improvement in my skin and nails. I will definitely keep taking this going forward,” one reviewer writes.

Highlighting the product’s great taste and results, one five-star review reads, “I have been taking these for several years now and my hair started growing again and I am very happy with the results. My hair started growing right away and I think it’s because of the combination of biotin and other vitamins that help your hair grow.”

“Love that these are so tasty! And they’re vegan! I’ve only been using these for about 10 days so I haven’t noticed any crazy improvements in my hair but overall I like these gummies and I’m excited to keep using them,” writes a reviewer.

A gushing review for the product reads, “I have struggled with finding ways to get my hair to grow and maintain its great texture. Well now, all of that has changed because I finally got supplements that help me and I can add into my daily routine. Primal Harvest’s Hair Growth Complex for healthier, thicker, fuller hair.”

“So far this is a great product as well. Great improvement with my hair, nails and skin,” reads a five-star review on the brand’s official website. “Another product I would recommend to my family and friends. Love it as well.”

A reviewer writers, “Since taking Growth Phase my hair has completely stopped shedding! It’s a true miracle, I really couldn’t believe it but I started to see the results from the 3rd week of taking it daily.”

Next up, A Rich Body Cream Unlocks Smooth, Youthful Skin—10 I’ve Vetted and Recommend