Horizontal ridges on nails, often called Beau's lines, are often the sign of a health problem, according to MedlinePlus. These ridges occur after an illness or injury to the nail and sometimes result from chemotherapy or... More »

Vertical ridges observed on fingertips are predominately caused by growing older. The medical term onychorrhexis is used to describe long, tiny, raised lines that run up and down the length of the nail. More »

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Fingernail ridges can be easily removed by buffing the fingernails with a four-sided nail file. Nails naturally develop vertical ridges as people age and applying vitamin E oil helps to moisturize the nails and prevent f... More »

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Fingernails and toenails marked by horizontal waves or ridges are typically the result of the medical condition known as Beau's lines, according to Skinsight. An abrupt interruption of nail keratin synthesis causes the w... More »

Vertical, or longitudinal, ridges on the nails are normal and do not indicate a health problem. Ridges that run horizontally along the fingernails usually indicate an overall health issue. These lines may be referred to ... More »

According to Dr. Standley, flat nails can indicate Raynaud's Disease, a condition characterized by cold fingers and toes. Flat nails can also be caused by an iron, protein or vitamin B12 deficiency, psoriasis or diabetes... More »

Thyroid issues do not cause ridges on the nails, but these issues might cause the nails to become brittle or split from the nail bed, according to MedlinePlus. Conditions such as anemia, injury and arsenic poisoning may ... More »