Trimming is important because:
1. It helps your hair look good and well looked after; It smartens you up. Unsightly hair ends are not attractive.
2. It gets rid of damaged hair. Damaged hair and split ends are more likely to get tangled with healthy hair; this extra friction encourages more hair damage and increased breakage.
3. It encourages growth. I'll be the first to admit that I don't understand how this works 100% but many people testify that taking care of hair ends helped their hair grow. I think this is likely due to better length retention.
If the ends are damaged and are allowed break off at will the hair that's left also has a damaged end which in turn is susceptible to further breakage.
With a pair of scissors you can cut the damage off clean leaving only healthy hair that doesn't tangle and cause friction.
So there you have it; as for how often you should trim, that's an individual choice but two to three times a year seems to be common in many naturals' regimen.
In addition, remember that "dusting" may mean that you can get away with trimming your hair less often. "Dusting" involves trimming so little hair that it looks like dust. This technique helps to stop split ends from happening at all. You can dust every 6 to 8 weeks. Just snip off a tiny, inconsequential amount to keep the ends healthy.
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