Her recommendations include both using a pre-treatment — like Philip Kingsley’s Elasticizer — and increased daily moisture. “Pre-treat the hair fiber by applying a protein treatment to dry, dirty hair before your shampoo, like a detoxifying oil or mask,” she says.Then, comb all of the product through and wrap it up in a low bun while you sleep. “This allows the hair to absorb the needed protein that will aid in strengthening the hair fiber, as well as providing the foundation for all of the moisturizing elements from the shampoo and conditioner, to properly adhere to the hair for maximum efficacy,” says Hill.Another route that can help: Products that create bonds with the proteins in the hair, to reinforce the cuticle during the process. “This protects the cuticle from too much stress which leads to damage,” explains Wilson. Try Olaplex No. 3 Hair Perfector, an at-home bond-building treatment.Keeping your hair hydrated is equally important. “Make sure to add daily moisture in small amounts, applied liberally to the damaged area and conservatively throughout,” Hill explains. “Moisture on the ends of the hair fiber will not weigh it down or make it greasy if it’s used properly and designed for your specific hair type and texture. For example, finer hair textures may consider using water-based leave-in conditioning sprays.” Giovanni Direct Leave-In Weightless Moisture Conditioner is a good option.Heat DamageA dependence on hot tools for your daily routine can reveal itself in multiple ways. “Heat opens the cuticles, allowing the hair to dry and shape when you are blow-drying or curling your hair,” Nation explains. “Too much can damage it, though — so using a heat protectant is necessary every time.” New York City-based trichologist Sophia Emmanuel adds that, “your heat-protecting product should protect styling up to 450 degrees.”Other ways to prevent heat damage, according to Emmanuel, is to use a heat setting appropriate for your hair texture, avoid applying heat on dirty hair, and try not to use heat every day. “A product for thermal protection would have ingredients that are either activated by heat to protect strands or can provide a protective covering around hair strands to prevent direct heat from inflicting damage,” explains Wilson.Thinning or Hair LossLots of different things can cause thinning and hair loss, including damage to the hair. Are thinning and hair loss one and the same? According to the pros, not exactly. “When a patient refers to thinning, they’re usually noticing less hair, thinner ponytails, a visibly wider part, and more of their scalp showing. When referring to hair loss they usually report noticeable increase of shedding,” explains Francesca Fusco, a board-certified dermatologist and assistant clinical professor of dermatology at Mount Sinai in New York City.