When hair is healthy, the third outer layer of the hair, the cuticle, shines. But when the cuticle is damaged or "broken," the scales on the cuticles separate and become dry, making the hair look dull. Fortunately, you can repair split ends and even prevent it from happening in the first place if you first understand the causes of split ends.

Causes of Split Ends

Broken hair is damaged hair, and many of the things you do to make your hair beautiful - from using harsh chemicals and styling products to the over-manipulation of the hair- can actually break the hair's outer cuticle, causing your hair to look brassy and dull. The following is a list of things that causes split ends; some will be easy to eliminate, others won't be so easy. If you find yourself unable to eliminate all of them from your routine, you're not alone. Just make sure you read the section about repairing damaged hair.

• Brushing your hair. The old wife's tale states that you should brush your hair 100 times every day for healthy hair, but brushing can damage your hair, breaking or weakening the outer cuticle. To avoid brushing, use a wide-tooth comb to pick through knots. If you can't avoid brushing completely, make sure you use a natural bristle brush and never, ever brush your hair when it's wet, as that is when hair is most vulnerable.
• Using harsh chemicals including permanents, dyes and relaxers. It's commonly thought that relaxers will heal broken hair, but the use of relaxers actually causes split ends. That's because the use of chemical relaxers and permanents manipulate your hair's chemical structure, causing the cuticle scales to stretch and break.
  Hair dyes are notoriously very hard on the hair and cause drying, damage, breakage and all of the above. If you do any of the above to your hair, you should use deep conditioners and/or a weekly hair repair treatment to prevent further split ends.
• Over-styling the hair. Over-styling is a big cause of split ends as it includes damage and caused by heat stylers, styling products and over-manipulation. To prevent split ends, limit your use of hair dryers and straighteners; this can include attaching a diffuser to your hair dryer, drying for only half the time, and/or styling with a straightener every other day or every third day as opposed to every day.

To prevent split ends caused by styling products, choose products with natural ingredients, as they won't damage the cuticles or dull their appearance. To prevent breakage caused by over-manipulation, don't wrap your hair in a towel, tight twist, bun or ponytail, and don't "play" with your hair.

How to Repair Split Ends

You can repair split ends with both hair repair products and home remedies. Home remedies for split ends include a variety of home conditioners, the use of including mayonnaise, mashed bananas and even beer. The benefit of using hair repair products is the ease of use. Read our top hair repair product reviews.