Iron

Iron is found in the core of red blood cells, which transport oxygen to all of your organs and cells, including your nails. Without iron, oxygen does not reach your cells in sufficient quantities. Because healthy nails require oxygen, an iron shortage or anemia can cause vertical ridges in your nails as well as concave or "spoon" nails. The RDA for iron varies greatly based on age and gender. Men should take 8 mg per day, while women aged 19-50 should take 18 mg per day. Women's iron requirements decrease to 8 mg per day around the age of 50 or when they enter menopause.

Iron from animal meals, such as beef, poultry, fish, and eggs, is better absorbed by your body than iron from plant foods, such as dark green leafy vegetables, peanuts, seeds, beans, and other fortified foods. However, combining a vitamin C-rich diet with a plant-based iron food source enhances absorption. Consuming oranges and strawberries alongside a spinach salad with beans and seeds, for example, boosts iron absorption.