One common sign of brittle nails is peeling layers at the tips. Others may notice excessive splitting, rough edges, thinning, or nails that bend more easily than before. These symptoms can develop gradually, making them easy to dismiss until they become severe enough to interfere with everyday activities.
Among the most common causes of brittle nails are nutritional deficiencies. The body requires vitamins and minerals to build and maintain healthy nail tissue. When these nutrients are lacking, nails may become one of the first visible places where problems appear.
Iron deficiency is frequently associated with nail changes. Iron helps transport oxygen throughout the body, supporting healthy cell growth. When iron levels fall too low, nails may become thin, weak, or develop unusual shapes. In some cases, they may even begin to curve upward.
Biotin, a B vitamin often linked to nail health, also plays a significant role. Although not everyone with brittle nails is deficient in biotin, studies suggest that adequate intake may help improve nail thickness and reduce breakage. Foods such as eggs, nuts, seeds, and legumes are natural sources of this nutrient.
Zinc is another important mineral. It supports tissue growth and repair throughout the body. When zinc intake is insufficient, nail growth may slow, and the nail surface may become more fragile. Similarly, deficiencies in vitamin B12, vitamin D, magnesium, and protein can contribute to weakened nail structure.
Protein deserves special attention because keratin itself is a protein. People following highly restrictive diets or consuming insufficient protein may notice changes in both hair and nails. Since the body prioritizes essential organs over cosmetic structures, nails often suffer when nutritional resources become limited.