What a product! I purchased a bottle for my lady. She is Romanian with beautiful black hair. I am the researcher in our relationship. She does the hard stuff and puts up with me. Her hair was damaged, thinning, and shedding. This product delivered as advertised!!! I am a big advocate for supplementation due to the average diet and low nutrient quality of processed, mass produced produce we ingest. Additionally, the chemically treated water we bathe and shower in requires us to be diligent in our body's ability to remain healthy. I am not paranoid, just practical. Our bodies are very resilient as long as we give it the tools to protect, rebuild and regenerate.I have her taking a high-quality multivitamin along with vitamin K2, magnesium glycinate, and one or two other supplements. When she expressed concern about her hair I delved into research mode and consumed tons of information. Biotin is often mentioned. However, I believe in a comprehensive approach to issues. This product not only contains biotin, but it also includes other co-factors needed for strong, healthy hair.After reading the ingredients the level and type of Vitamin A caught my attention. You see, this isn't the veggie based caratoid pre-cursor "A" that your body converts to the utilized version. This is the converted Retinyl Palmitate form of A, which is fat-soluble and stores in your liver for a long time. If you take too much, over time it can build up to toxic levels resulting in serious problems including permanent liver damage. I often stress more is not better as applied to supplementation.The upper limit of Palmitate A is 10,000 IU a day. Two of these pills contain 8000 IU. When I consider this is likely NOT the only source of A we ingest each day, I feel this dose is a bit high for long-term consumption. When I say long-term I am talking nine months or more of daily 8,000 IU intake on top of our other daily sources. I don't think 60 to 90 days or even six months would be an issue for any healthy individual.Photo 1 = Day 0 || Photo 2 = Day 26 || Photo 3 = Day 49 (approx. 2 weeks prior to this review)My Romanian princess took one bottle at the recommended does of two capsules per day. Within three weeks her hair was noticeable thicker, shinier, softer, and stronger. Also, in just three weeks her shedding all but stopped when she brushed or washed her hair. Within 30 days there was no mistaking the marked improvements resulting from this product and there is no more shedding. Please consider I have always had her on a quality multivitamin as well. So it may be a combination of everything she had been taking with this product being the missing link to healthier hair.After her first bottle I had her reduce the dose to one capsule per day and bought her a separate biotin (2500 mcg) to take with it for a total of 5000 mcg of biotin. We may experiment with taking two capsules every other bottle and only taking one capsule with added biotin every other bottle. Once we are where she wants her hair to be, we will look into dropping down to one capsule a few days per week (or every day) for maintenance along with her other supplements. Her hair looks amazing and it has grown just over an inch (it was already fairly long). Her nails are also growing much quicker (she tells me). She and I are very pleased with the results.TIP 1: Biotin can cause breakouts. I theorize sudden high doses of biotin over stimulate sebaceous glands, causing them to become mildly inflamed and/or over active. Just a theory. Whatever the case I have the solution, which is very simple. Start off with a low-dose of biotin for a few weeks. Don't just introduce thousands of mcg's to your system overnight. Allow your body to adjust to this increased supply after all of these years. Depending on the person you may get away with 1000 mcg, but even that may trigger a few deep painful bumps in some. You can purchase a bottle of 300 mcg instead. Take one per day for a week or so. Then double the dose by taking two per day for ten days to two weeks (600 mcg). Then triple the dose by taking three per day for two weeks (900 mcg). Don't rush it. Now your body is ready for the higher dosage.TIP 2: Personally, I don't see a need to take 10,000 mcg of stand-alone biotin. Instead, after you acclimate your body via TIP 1 (above) take two of these pills a day for one or two entire bottle(s), then drop down to one of these per day BUT also take up to 2500 mcg of stand-alone biotin with one of these either together or separately. Doing so reduces the chance of too much "A Palminate" yet provides you with up to 5000 mcg of biotin along with the other much needed co-factors for long healthy hair. Biotin alone requires massive doses to be productive. This comprehensive approach will yield better results. If you wish to be extremely cautious, you may consider taking only one capsule of this product per day (versus two) for the first week or two to see how it effects you.TIP 3: Don't forget your protein. Your hair will thank you for it. I am 6'1" at approx 210 ilbs. I eat two organic eggs each day for breakfast. I also consume a powdered protein smoothie about three days per week. Most people consume protein on a regular basis. So you are likely fine.TIP 4: How are your iodine levels? 100 - 300 mcg three or four days per week might be helpful for your hair. Do NOT go overboard with iodine. Also, watch your source as some brands contain heavy metals, which are bad for you. Pure Encapsulations is one of a few brands I trust at the time of this review.TIP 5: Consider installing a shower filter to remove some of the chemical cleansers out of the water you bathe in. I can recommend a couple that I read about in a nutrient book called "It's Not The Cans". They are very effective.TIP 6: If you are unsure about a seller, buy directly from the manufacturer, ZHOU.TIP 7: Always check the expiration date when buying from third party sellers.I really hope this product works as well for you as it is working for us. I am a real person with zero ties to this product, seller, or manufacturer.