oy nails are really weak and I have no idea about what may be causing the problem. Any ideas?
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There could be many reasons why your nails are so weak. The most common is washing up! Avoid leaving your hands in hot water as much as possible and always remember to wear rubber gloves when doing the dishes.
A great investment is emery boards, you can buy packs of 5-10 so you can always have one handy, keep them spread out all over the house, in your car and your handbag.
Another essential is a good nail strengthener. You can pick them up at any local chemist or supermarket, apply one to two coats every couple of days and your set.