A lack of oil in the hair will always result in dry hair. This lack of oil is commonly caused by heated styling. When trying to eliminate dry hair, you will need to eliminate the heat. Just as with dirty dishes, washing with hot water will cut oil in no time flat. The same goes for hair, washing dry hair in warm water is much more beneficial because it allows the hair to retain its natural oils.
Blow drying is also an action to avoid. As with hot water washing, hot air drying breaks down the natural oils in hair, leaving hair dry and brittle. Air drying is the only way to prevent this break down of the essential oils needed to keep hair moisturized. Stop blow drying and the health of your dry hair will improve nearly immediately.
Chemicals are the second most important item to keep out of dry hair. While heat can damage hair tremendously, chemicals can do even more damage. Dry hair caused by chemical damage will take much longer to treat. The only real solution after dry hair has been over treated with perms and hair coloring is time. Time for the hair to grow back out from the roots.
Dry hair can be treated with a saturation of conditioners. Conditioning during showers (even when you do not shampoo), conditioning before bed and conditioning when just sitting at home watching television are all needed to help rehydrate dry hair. The conditioners you use on dry hair need to be very thick in nature. Hair dresses and mayonnaise style treatments are perfect for sealing the moisture and oils into the hair shaft. The more you condition, the more moisture will be retained.
Dry hair can occur thanks to a multitude of reasons. From climate to body changes, but one thing remains constant no matter the cause of the dry hair, heat and chemicals will not help to better dry, brittle hair.