Despite endless hours - and dollars - spent on their hair, every woman has had a bad hair day or two. Having great hair plays a key role in a woman's self-confidence and self-esteem. Yet according to the American Academy of Dermatology, 30 million women -one in four - experience thinning or hair loss at some stage of their lives, most commonly during menopause or post-pregnancy. The causes can range from stress to poor nutrition to environmental changes and even daily shampooing and styling, according to Dolisos America Inc., a nutritional and pharmaceutical products company. Considering the societal pressure on women to look their best, hair loss or thinning can have a devastating effect on self-esteem and may even lead to depression. Dolisos offers some ideas on how to be kind to your hair and nourish it from the inside out: * Check your roots. Hair loss in women can be attributed to a history of female pattern baldness. Investigating possible genetic causes of your hair loss can help you decide the best course of action to take. * Feed your follicles. It's important to eat a balanced diet to nourish not only your body but your hair as well. Treat your tresses to foods rich in protein (fish), zinc (shellfish), iron (wheat bran), and vitamin C (many vegetables and fruits). * Drink water. Consuming at least a liter of water a day helps the body expel toxins and provides optimum conditions for cell growth. * Consider over-the-counter hair repair. Certain supplements like Eluhair are designed to nourish the hair and promote its growth. Two Eluhair capsules taken daily may help combat the effects of temporary hair loss due to hormonal imbalance, unbalanced diet or stress.