Split ends are the point where a hair strand frays and divides, and once a strand splits there is no product that truly fuses it back together. That is the honest starting point, and it shapes everything else about how to handle them.
Why products can't mend a split
Serums and bond-building treatments can temporarily glue a split shut so it looks smoother and feels softer, but the repair washes out. If you leave a split end alone, it tends to travel further up the strand, causing more damage over time.
- Trim regularly: a small cut every couple of months stops splits from climbing.
- Smooth temporarily: a sealing serum on the ends improves the look between trims.
Prevention is the real fix
Since you cannot reverse splits, the goal is to slow new ones. Heat, rough brushing, tight elastics, and friction from cotton pillowcases all create them. Reducing those does more than any repair product.
Brush and dry kindly
Detangle from the ends upward with a wide-tooth comb, especially on wet hair when strands are weakest. Pat hair dry rather than rubbing it rough with a towel.
Trim to stop the spread, treat the ends gently to slow new damage, and accept that the only permanent fix for a split end is scissors.