Split Ends, and the Honest Truth About Sealing Them Until Your Next Cut

The medical term for split ends is trichoptilosis, and it happens when the shingle-like cuticle wears away at the oldest part of the strand and the inner cortex frays like a cut rope. Dermatologists class it as hair weathering, caused by styling, sun, wind, humidity, salt water, chlorine and friction. Hair is not living tissue, so a split cannot be permanently fused; McGill University's science office says a haircut is the only effective way to remove split ends and that products only mend them for a while. That is the honest frame for everything below. Kérastase, which launched in Paris salons in 1964 and which L'Oréal credits with the first care serum, makes the serum that seals and smooths. Olaplex began in 2014 when Dean Christal got his first sample from a scientist's garage in Santa Barbara, and its 5L leave-in moisturizes the lengths. Moroccanoil's mending serum is the quick fix before you go out, and Ceremonia, from Babba Rivera, makes silicone-free guava hair care. Book a regular trim every eight to twelve weeks and use these in between.

Bond treatments work inside the strand, which can make hair stronger against new splits even if they cannot fix old ones. Living Proof came out of Dr. Robert Langer's MIT lab in 2005, adapting a polymer first developed for gene therapy, and its triple bond leave-in strengthens and smooths. Oribe's Hair Alchemy leave-in is from the brand Oribe Canales started in 2008. L'Oréal Professionnel dates to 1909, when the chemist Eugène Schueller invented what the company calls the first harmless hair dye, and the Absolut Repair leave-in is its bond-building answer. Amika, whose name means friend in Esperanto, makes Midnight Mender to wear overnight and reduce hair breakage.

Jonathan Van Ness built JVN around hemisqualane, a silicone alternative made by fermenting sugarcane, and the Revive mask adds shine to damaged hair fast. Bumble and bumble's bond-building shampoo and conditioner are the everyday pair, and Indē Wild, which Diipa Büller-Khosla started from the Ayurvedic rituals she grew up with, makes the Champi shampoo to cleanse without stripping. Her mother is both a dermatologist and an Ayurvedic practitioner. What I would skip is anything promising to glue splits back together for good. Nothing can do that, and the claim usually means a coating that washes away. Treat products as maintenance and the scissors as the fix.

Sleep on silk, detangle from the ends up and keep your tools on the lowest heat that works. Use a heat protectant every time. Get the cut before the splits travel up the strand. Then use a leave-in daily so the new ends stay smooth for longer. Swap rough cotton towels for a soft T-shirt or microfiber wrap to cut friction. If you want to keep browsing, I also put together Hair Cutting Scissors, From Bronze Blades to a Home Cut Kit and Hair Oil for the Ends and for the Scalp.