Summertime means soaring temperatures and high humidity. The latter is something that many people (myself included) avoid at all costs. Not only does it make my skin feel sticky and sweaty, but it also does a number on my hair. It's not about how it looks. In fact, I love my big curls and breezy flyaways that result from humid weather. It accentuates my hair's natural shape like no heat tool or hair product can. So while I love the way humidity makes my hair look, I hate how humidity makes my hair feel. The air's extra moisture seems to roughen up my hair's cuticle, making it brittle and dry. Even though I take good care of it and its everyday damage is minimal, all it takes is one humid day for me to feel like I need a deep-conditioning mask asap. That's why I hoard smoothing hair serums.
Just like skin serums, hair serums nourish and hydrate. They seal the cuticle, making each strand of hair look sleek, shiny, and healthy. They're also incredibly low-maintenance. Most of them can be applied on dry hair whenever it bests suits you, which is why they're so convenient for summer. Keep scrolling to see the 12 smoothing serums that will leave your hair looking (and feeling) amazing no matter the air's moisture content.
This is one of my personal favorite hair serums. I use it like I would a leave-in conditioner. Once my hair is dry, I slide a dollop through my hair, concentrating the bulk of the product on my dry (oftentimes split) ends. It immediately smoothes and moisturizes the cuticle and makes my hair feel much more manageable—especially since it helps detangle any knots. It's all thanks to the lipids, baobab polysaccharides, and hibiscus extract found inside.
This Sephora-approved clean beauty product is also a Byrdie editor favorite. It combines ingredients from coconuts, olives, almonds, and other natural sources to make a creamy vegan hair serum. It smoothes, increases shine, and nourishes hair to protect against damage. Take it from us, as it makes even the most brittle and straw-like ends feel silky.
Just like a facial CC cream, Alterna's hair version is multifunctional. In this case, that means it works as a styling cream and as a leave-in conditioner. It even works as a heat protectant, defending hair up to 450 degrees. It has 40,000 "loves" on Sephora's website, with reviews like this: "This is a unique and one-of-a-kind cream. I have thin, wavy, and frizzy hair. I use a few pumps on damp hair and air-dry my hair, and then I use a few more pumps on my dried hair. It gives my hair shine, control, and takes care of the frizz. This can be used again the next day without weighing the hair down. Keeps it soft and shiny. Will be stocking up soon."
This styling cream is both a smoothing serum and an anti-breakage product. It has coconut oil, shea butter, moringa oil, hibiscus, jojoba, and silk extracts to transform the texture and health of the hair. It's specially formulated for damaged, rough, and weak hair and promises to stop shedding and breakage almost immediately.
This Redken pick does everything that you want an anti-humidity product to do. It defends against moisture, smoothes the hair cuticle, and adds shine. Plus, it's much less expensive than other high-end serums that claim to do the same thing. Reviewers agree. "This one of my favorite finds. My hair is thick, curly, and I have a lot of it. I dye my hair and wash more often than I should, so my hair dries out. This smooths out my frizz, adds shine, and doesn't weigh my hair down like oils and other products."
What's unique about this Bumble and Bumble pick is that it combines the hold of a gel with the hydration of an oil for extra-shiny, sleek hair. That doesn't mean it makes your hair straight, though. In fact, it does the opposite, defining your curls and giving them extra bounce and movement. (Make sure you check out 11 other products for curly hair.)
This French smoothing serum from Leonor Greyl is one of my all-time favorite hair products. Almost every single day I swipe two pumps of this through my strands for extra softness, shine, and manageability before heading out the door. It's all thanks to jojoba, wheat germ, and hazel seed oils, which respectively hydrate, strengthen, and smooth the hair. It's kind of a classic as far as hair serums go, and it's a longtime Byrdie editor favorite.
L'Oreal's Elvive styling line is a drugstore force to be reckoned with, and this smoothing hair serum is no exception. Its star ingredient is argan oil, which locks in shine and sleekness for days. When we say "days", we mean it. The brand promises smooth hair for 72 full hours.
Now for an Italian hair smoothing serum. High-end brand Rossano Ferretti prides itself on using ingredients that are normally only found in skincare products to give your hair some extra TLC (think hyaluronic acid). It's formulated with pure coconut oil, nourishing butters, and a combination of other seed and kernel oils—all of which add smoothness and shine to roughened hair. One Sephora reviewer writes, "I love this product! The smell is amazing and it makes my hair look great when I apply it and comb through right after washing. I wish it weren't so expensive, but this is the product from the smaller set that I can't live without. Try it, especially if you have layers or curls and air-dry."
100% Pure is a fan-favorite clean beauty brand. This serum, like so many of its other products, is formulated without toxins, parabens, or petrochemicals. It's vegetarian-friendly and rich in vitamins E and B5, both of which smooth and hydrate the hair strand.
You might recognize the Marajo brand from its main ambassador: Victoria's Secret model Alessandra Ambrosio. It's a good fit. After all, Ambrosio has amazing hair, and she's from Brazil, which is also the home of the brand. This serum can be used on both wet and dry hair to provide it with smoothness, softness, and supermodel-level shine.
I was lucky enough to see a sample of this come across my desk recently. I immediately opened it (because what is patience?) and fell in love with it after running the first pump through my mid-lengths and ends. The silky oil sinks into my strands without making them look greasy or weighed-down the way others are wont to do. My fine, thin hair literally drinks it up, and now I can't imagine ever going without it. It's that good.
Now that you're up-to-date on some of the most beloved smoothing hair serums on the market, make sure you check out 17 vegan hair products you need for summer.