The scientific term for Split ends is "Trichoptilosis". Split ends are inevitable for anyone with hair. It occurs when there is any kind of damage to the cuticle. Damaged or missing cuticles leaves your fragile cortex exposed (located between the hair cuticle and medulla. It's thickest hair layer and also contains most of the hair's pigment). Without the proper amount of protection from your cuticle layers, your hair strand will begin to split into two or more sections.
Split ends are not necessarily just a split in a strand. On a microspic level, it's really a very rough tear in your strand similar to what it looks like when you break a wooden branch. That's why when you have a lot of cuticle damage to your ends, it appears more frizzy and bushy (as seen in the illustration above).
Most splits start out as single splits and can evolve to a triple, feather, tree, double y, long or deep split. The progression is inevitable, but we can be take certain measures to help keep them in check.
The Four Most Common Types of Split Ends
A hair strand split in two on the ends is the most common and is part of the natural process of regular wear and tear that your hair goes through. Usually the more complicated splits start out as single splits. Your hair never really splits into two equal parts; one branch of the split is usually a lot thinner than the other.
Some have said that splitting ends left untreated will continue to split up the entire shaft, but that is not exactly the case. Tapering occurs when one of the branches, usually the thinner one breaks off. So what's left behind is a thinner hair strand starting from where the branch broke off down to the end of the hair shaft. Depending on the angle of the split, the tear can reach fairly high up the hair shaft, but the majority of the split peels away or break off from where they originate. And where the split has already broken or peeled off, the ends are thin, see through type ends.
I think we were all led to believe that we must trim or cut our hair when we have split ends to avoid the split from traveling up the hair shaft. When a split occurs, it never really happens down the middle. One branch is often thinner than the other as I just mentioned and because of that, the thinner branch usually peels away or breaks off. You can pamper and take care of your ends to substantially slow down the process of forming new splits.
Incomplete splits or holes occur mid-shaft. This usually occurs when we wear our hair in tight ponytails or what have you. If worn too tight the area of your hair that is in contact with the hair tie becomes weak and experiences a lot of cuticle damage. Because it occurs mid-shaft, the split will usually start off as an incomplete or a hole. The thinnest branch will break off leaving a very thin weak section mid-shaft and a new deep split occurs (see the progression in the illustration).
Another type of split end is a kind of small break in the shaft known as 'trichorrexis nodosa'. These are the areas where the hair's cortex has swollen and exploded within the shaft as a result of heat styling, excessive brushing or use of chemical treatments. You can tell these type of splits by the noticeable white dots most commonly on the ends of the hair shaft.
Split ends may occur for a variety of reasons. A few of the most common reasons for split ends are color treating your hair, using relaxers, frequently applying heat to your hair without the use of heat protection, hygral fatigue and rough handling. Split ends however, are a normal part of wear and tear. The less abuse, the less damage there will be and vice versa, the more abuse the more damage there will be.
How to Slow Down the Process
There is no way to really prevent split ends. Unless you know how, please share. Unless your hair is not touched or moved, split ends are going to occur. One of the things you can do is improve trimming methods. Make sure the shears you use is sharp as possible. This makes your cuts a lot smoother. Only use your shears for your hair and not something else to avoid making them dull.
Also, obviously reducing heat and chemical use on the hair will help lessen split ends. The more cuticle damage you have, the more split ends. If you do decide to use heat, make sure to use a heat protectant.
Deep conditioning and protein treatments are great for split end prevention. Protein treatment strengthens your cuticles. Stronger hair cuticles will make split ends less likely to occur. While moisturizing deep conditioners help restore your hair's moisture balance, it will also result in more elastic hair.
Other methods to prevent split ends, LCO method layering in order of the product's density or water amount makes it easier for the water molecules to absorb into your hair. With the LOC method, the cream sits on top of the oil, the oil is blocking your hair's ability to absorb moisture and nutrients from the cream. What the popular LOC method does is that it creates a shiny illusion. It's not the hair that's shiny, it's the cream that's sitting on top of the oil that was not able to absorb into your hair.
The most any product can really do is to mend damaged cuticles. So if you already have split ends, use protein treatments to strengthen and slow down the process of forming new splits. Also, trimming is important, but if your goal is to gain length you shouldn't trim your hair too often. With proper care you can limit trims to twice a year rather than 4-6 times a year.
Sources: Science of Natural Haircare, CurlyNikki.com.