Hair growth and thickness can sometimes be boosted by improving the range of vitamins and minerals in your diet. Vitamins A, B, C, D and E all play a role in the development of your hair and contribute to growth, antioxidant protection and reduced oxidative stress. Collagen is also a common ingredient in hair care supplements as this contributes to a healthy scalp, helping to maintain your hair growth longer. Some vitamins have been related to hair growth, while others contribute more to hair thickness, so it’s always important to take a closer look at each product and how they can improve your specific hair needs before you buy.