Indian women—who have beautiful luxuriant hair—are known to make it even more glossy by applying a paste of mashed bananas and avocado oil on the hair as a mask. This tip comes to us straight out of a beauty column in an Indian newspaper. While good health and good nutrition usually show up in nice-looking hair, there are not really a lot of specific supplements to boost hair health. The best one we know is black currant oil, which helps thinning hair, split ends, and is good for fingernails. You can get this at health food stores and vitamin outlets, but be prepared to take it for a few weeks before you notice any improvement.