Garnier Fructis Keratin Sleek & Stay Serum

Excellent product! This serum exceeded my expectation. My hair has not felt as smooth & frizz free in years, I have tried numerous products and started thinking my straightener was no longer efficient, so I brought a new one and it was the same, straight but not smooth and sleek. I then figured maybe its just my hair now and I can't get that smoothness any longer, even when straightening. I used the serum straight after using the Keratin sleek shampoo, conditioner and mask and applied it to wet hair and let it dry naturally, which showed improvement in frizz already. Straightening my hair seemed a game changer for me. I felt like I had it professionally done and it lasted days. Usually humidity will make it frizz and lose smoothness, but it even with the hot days it stayed smooth for 3 days before I washed it again. I am very impressed with the results. The benefit of saving time for morning styling between washes is an added bonus. This serum is now part of my regular routine.

I’ve been using the Garnier Fructis Keratin Sleek & Stay Serum for the past two weeks. I apply one pump through damp hair before blow-drying. The serum spreads easily, has a light, pleasant scent, and immediately makes my hair feel softer and smoother. My hair stays frizz-free and manageable throughout the day, and even thicker sections are easier to style. It adds shine, makes my hair look polished, and significantly improves overall texture. This serum has become an essential step in my hair routine.

This is the ultimate secret weapon for faking that super glossy, reflective "glass hair" look. Just one teeny-tiny pump on damp hair right before blow-drying? Chef's kiss. 🤌 A little bit on dry hair to instantly tame those random flyaways during the day? An absolute lifesaver! It creates this invisible shield that locks out frizz and humidity, leaving you looking so incredibly sleek and polished. But a serious word of warning for my fine-haired besties: a little goes a loooong way, so don't go crazy!!!

I was really excited to try this product as I use heat a lot to style my hair and I don't see heat activated serums very often on the market. I’ve been using this heat activated serum before blow dry and after straightener and it has definitely helped my hair health. It applies really smoothly and distributes easily. Once heat is applied, my hair feels much softer, sleeker, and healthier. It does a great job at helping control frizz and flyaways, even in humid weather, and my hair feels protected from heat styling damage. I also love that it doesn’t leave my hair feeling greasy or weighed down, which can be an issue with some serums. I think it's awesome that this is both a serum and heat protectant in one. Will definitely keep using this and I can happily recommend it to anyone who regularly uses heat styling tools and likes serums.

I have been trying all of the products from this range (the shampoo, conditioner, and hair mask) and this is definitely the stand out product! It makes such a difference with the amount of frizz in my hair. When I use this my hair is so much smoother and healthy-looking, but it doesn't feel heavy because it is a thin, watery texture. I love that it is a heat protectant as well, because I usually have to use a hair serum and then an additional heat protectant so I love that this combines those two products. Overall, this product has made styling my hair so much easier, and has resulted in much sleeker, softer, shinier hair. This is definetly a product I will be repurchasing!

Keratin Sleek & Stay Serum was easily my favourite product out of the entire Keratin Sleek system. From the first use, it made a noticeable difference to how sleek, smooth, and shiny my hair looked and felt. The heat-activated formula works exceptionally well when blow-drying or styling, helping to seal the hair fibre and dramatically reduce frizz. My hair looked more polished, glossy, and controlled. The serum provides excellent heat protection and helps maintain smoothness for days, even through humidity. Unlike other serums, it absorbs well and leaves hair soft, shiny and silky. This product genuinely delivers on its promise of long-lasting smoothness and shine, and I would repurchase it on its own even without the rest of the system.

This product instantly helps reduce frizz upon application. When used before blow drying and straightening it left my hair looking shiny and healthy. It also helped my hair stay straight for longer than when straightened without any product. I used this product between washes when my hair was exposed to humidity and became frizzy. It is definitely a multi use product and can be used as a heat protectent, hair oil and hair serum. I would recommend this product to people with very dry hair because it can leave hair looking a little greasy on normal to moderately dry hair.

After spending 3 weeks away in a really cold environment, and forgetting to take anything moisturising for my hair, I returned from a recent holiday with extremely dry and frazzled hair. From the first application, I noticed a difference in the texture and feel of my hair - less frizziness, and much smoother. After 2 weeks, my hair is now significantly smoother and softer. I love the beautiful soft fragrance, which lingers well after applying. I am so happy with the decrease in frizziness also. The serum pairs beautifully with the shampoo, conditioner & mask in the range. I would definitely recommend this to anyone with thick, frizzy hair and I this is now my new favourite serum and hair care range.

This hair serum is designed to be used on damp, towel-dried hair and effectively reduces frizz. I like that it also acts as a heat protectant, meaning that I don’t have to worry about a separate product for that. The instructions do state to evenly distribute one pump of the product, however the first time I did this it left a slightly greasy film over my hair where there was more product. After using it a few times, I have found that the best way is to apply less than a pump to part of my hair, and then another half pump to the rest in order to spread it out evenly. Overall though, I would recommend this serum to people without fine hair. I noticed on the days when I used it that my hair became sleek and was less frizzy after blow drying.

I have fine hair with some wave and movement, prone to oiliness. In the past I've found most serums leave my hair greasy and limp, even when used sparingly. Surprisingly, this hasn't been the case with this product. I have been using just one pump and raking it through my mids and ends while still wet, and using the leftover on my palms to smooth over my crown. It's done great things for my fly aways and shine. I'll definitely keep experimenting to see how this goes as a standalone product on non-wash, humid days.

Worth noting before I launch into this review that I used the full 4 steps of the Keratin Sleek range. Step 1: shampoo to gently cleanse hair and scalp Step 2: conditioner to detangle and soften Step 3: mask to smooth and control frizz and add shine Step 4: heat activated serum that coats hair with a waterproof and heat protecting film I’ve got thin and fine hair that has lots of baby hair that likes to pop up all frizzy. When I blow dried and straightened in the past it just didn’t want to stay down. The serum is the last step and I made sure to shake well as per instructions. It’s a small bottle but a little goes a long way. I rubbed it onto my hands then through my hair. I felt good knowing it’s also a heat protectant. It was light and not sticky. After using this range I found it controlled the frizz and made my hair look smoother for longer. It helps that the range smells great! It maybe felt like a bit longer of a time investment at the start with the mask and then blow drying and straightening but then my hair looked better for longer so overall I’d say it saved time. It’s great that the serum is also a heat protectant. Overall it’s affordable and works well so I’m keen to keep using!

This serum has a light oil texture, but it doesn’t leave any heaviness or greasy feeling on my hair. It absorbs well and leaves my hair smooth and polished rather than oily. The instructions recommend using a flat iron with one slow pass per section after applying the serum. I usually wash my hair at night, so using a flat iron before going to bed felt like a bit of a hassle at first. However, once I tried it, I noticed a big difference my hair was much easier to style the next morning and looked smoother overall. After using the full 4-step routine, including this serum, I can genuinely feel that my hair is in much better condition. It helps seal everything in and makes the whole routine feel complete. A great finishing product for smooth, manageable hair.

Hmm the Step 4 Sleek and Stay serum was my least favourite of the range and I found it to be a very disappointing experience. It felt quite sticky and heavy on application and made me hair look weighed down and 'not washed' in spots. Considering how great the shampoo smells, this serum doesn't smell great at all. Very off putting... For the size of the bottle, the price point is more than I'd be happily to pay for this product. Would have been great if there was a spray version instead. I have to admit, there are allot of better quality, nicer scented serums that are exactly at the same price point or slightly a little more. The fact that it's heat activated too means that you need to use heat on your hair to see any real benefit to using it. As someone who lets their hair air dry at times, this was a real downside. Sadly I can't really find anything to rave about when it comes to the serum. After such a great experience with the other steps in the range, I was expecting a great serum to wrap up the routine.

Love the Garnier Fructis Keratin Sleek & Stay Serum and the hair care range. This product has a texture on the thinner side which is quite easy to apply even on the hair. After blow drying, it makes my hair instantly sleek smooth and shiny. It also has a refreshing smell which is subtle and not overwhelming. The serum is great value that a small amount seems to be enough for my thick medium length hair. I would recommend this great add on product which works nicely with the other products in the range.

I really enjoyed using the Garnier Fructis Keratin Sleek Heat Protectant Serum. I am not someone who normally uses a serum but this one really felt great on my hair. I have very frizzy hair and found after using it that my frizz was well controlled, I used the other steps and styled my hair with heat and it looked so shiny, I was even complimented on the shine. A small amount goes a long way and I also would put a little extra in between wash days for a quick refresh. The same refreshing smell is in this product which I love. Definitely recommend this product.

Among the entire range, this product is my least favorite, possibly because I am comparing it to other hair serums I have used before. I followed the instructions carefully by applying it to my hair before blow-drying and ironing. The product has a pleasant scent and a nice texture when first applied, but in my opinion it feels more like a hair oil than a true serum. After drying and styling, my hair did look noticeably shinier and less frizzy, which I appreciated. However, despite the added shine, my hair still felt slightly dry and not as nourished as I expected from a serum. It’s probably not for my thin hair. For it’s price, I think it is still a good serum. I will still recommend this to my family and friends with thick hair.

I received the Garnier Fructis Keratin Sleek & Stay Serum to review as part of the BeautyCrew Review Crew. I absolutely loved the way this protected my hair when using it with straighteners, I wasn't worried so much about holding my hair in the straighteners for too long. It smells lovely and I love how shiny my hair looked after using it. I felt like I had been to the hairdresser, my looked fantastic, even with how humid this summer has been recently. It comes in a very convenient sized container and it is easy to pump out exactly what you need and not be wasteful, I have thick hair that sits just below the shoulders and felt like I didn't need to user much to get great results.

I have medium length, normal hair that tends to get frizzy, and this serum ended up being my favourite product in the whole lineup. I followed the recommended method of using a hair straightener to activate it, and the difference was incredible. My hair looked beautifully shiny, smooth, and polished, to the point where my husband immediately noticed without me even mentioning I had used it. On one occasion I tried it without the heat activation method and it was noticeably less effective, so I definitely recommend following the instructions. The texture felt lightweight and did not leave my hair greasy or weighed down. I was genuinely surprised by how well it performed and how professional my hair looked afterwards. It is one of those products that actually delivers visible results and quickly became a standout in my routine.

I’ve really enjoyed using the Garnier Keratin Sleek & Stay Serum as the final step in my hair routine. A small amount goes a long way, and it instantly helps smooth frizz and tame flyaways without making my hair feel oily or weighed down. It adds a beautiful shine and keeps my hair looking sleek and polished throughout the day. I especially like applying a little to the mid-lengths and ends after styling, as it helps everything stay smooth and neat for longer. The formula feels light and non-greasy, and it doesn’t leave any sticky residue behind. It’s perfect for everyday use and makes a noticeable difference in how soft, shiny, and controlled my hair looks and feels.

This serum was the product I was most looking forward to trying, as I had not tried something like it before. And wow, was my hair amazingly sleek! The serum definitely worked, as the next day was humid and usually my hair becomes very frizzy and incredibly hard to control (most of the time I give up and pin it up), but my hair was straight and sleek with no frizz in sight all day. I did not even need to re-straighten it. I did notice that the serum unfortunately did not last as long as it was advertised, but I honestly did not expect it to last as long as it did because my hair can be unruly. Definitely will recommend and keep in my go-to products.