The One Leave-In Conditioner You Should NEVER Use Because It Causes Thinning Hair

“Sulfates can strip the hair of its natural oils, break down proteins in the hair, slow down and potentially stop hair growth," she says of the harmful ingredient. 

This doesn't only apply for leave-in conditioners and treatments. Dr. Shah says it's best to ditch every hair product you have that contains sulfates in order to protect your strands and prevent hair fall. 

She also recommends switching out any products that contain irritating preservatives like propylene glycol as they can negatively impact the thickness of your hair as well. 

"Preservatives like propylene glycol can also cause scalp irritation, which can also lead to hair loss,” Dr. Shah explains. She suggests swapping any products with preservatives with products that are rich in protein to give your hair the strength it needs to be healthier and shiner. 

Dr. Roopal V. Kundu, MD, Associate Professor of Dermatology at Northwestern University's Feinberg School of Medicine, on the other hand, says you should invest in hair products that contain silicones for their protective properties. This is especially the case for a leave-in conditioner! 

"Silicone basically coats the hair, which adds a little more protection once you do any kind of stress to the hair," he tells Huffington Post LIFE. "Check a product's list of ingredients and make sure silicone is high up on the list. Look for silicone or dimethicone, a silicone derivatives. Anti-frizz products usually have a silicone type of derivative."