According to Healthline.com there are 8 vitamins and nutrients that help build healthy nails.

1. Biotin ~Biotin-rich foods and supplements may help strengthen your brittle fingernails. A few small studies support biotin supplement use to that effect.One study in 35 people with brittle fingernails found that 2.5 mg of biotin per day for six weeks to seven months improved symptoms in 63% of participants. Biotin is most concentrated in organ meats such as liver, but can also be found in egg yolk, dairy products, yeast, salmon, avocado, sweet potato, nuts, seeds and even cauliflower.
2. Other B Vitamins ~ Other B vitamins are also important for nail health. Vitamin B12 plays a role in iron absorption, as well as the development of red blood cells. Both iron and B12 are necessary for keeping nails strong and healthy. A deficiency in vitamin B12 can result in entirely blue nails, bluish-black pigments with wavy longitudinal dark streaks and brownish pigmentation (5Trusted Source, 6Trusted Source). Likewise, folate, or vitamin B9, is important for nail growth and health by contributing to red blood cell formation and the development of new cells.
3. Iron ~ Iron composes the center of red blood cells, which carry oxygen to your organs and every cell in your body — including your nails. Your body absorbs the iron found in animal foods, such as beef, chicken, fish and eggs, better than that in plant foods like dark green leafy vegetables, peanuts, seeds, beans and other fortified food. However, eating a food rich in vitamin C together with a plant-based iron food source improves absorption. For example, eating oranges and strawberries alongside a spinach salad with beans and seeds improves your iron absorption.
4. Magnesium ~ Magnesium is a mineral involved in over 300 reactions in your body, including protein synthesis, which is required for nail growth. Whole grains, specifically whole wheat, are a rich source of magnesium. Dark green leafy vegetables, as well as quinoa, almonds, cashews, peanuts, edamame and black beans, are good sources, too.
5. Protein ~ Nails are primarily made of a fibrous structural protein called keratin. This is what gives nails their strength and resilience. It also protects your nails from damage or stress. Eating enough protein through your diet is essential for boosting keratin production and thus creating strong nails. Protein can be found in animal foods like meat, poultry, fish, eggs and dairy, as well as plant foods, such as soy, legumes, beans, lentils, nuts, seeds and whole grains.
6. Omega 3 Fatty Acids ~ Omega-3 fatty acids can help lubricate and moisturize your nails, giving them a shiny appearance. Fatty fish like salmon, trout, mackerel, tuna and sardines top the charts with omega-3s, but they can also be found in walnuts, soy, eggs, chia seeds, flaxseeds and fish and flaxseed oil.
7. Vitamin C ~ Vitamin C is essential for the production of collagen, a protein that gives shape, strength and integrity to many tissues and is the building block of fingernails, hair and teeth.
8. Zinc ~ Zinc is required for many reactions in your body, including the growth and division of cells. Nails are made up of a type of cell that grows and divides rapidly. Because of this fast production, a steady supply of zinc is needed to promote the healthy growth of nails. Animal proteins like beef, poultry, fish and eggs are rich sources of zinc. However, soy, chickpeas, black beans, nuts (such as almonds and cashews) and seeds also contain it.