Causes of onychorrhexis include aging and health conditions, such as bulimia, anorexia or cancer, or their treatments, according to Nails Magazine. Psoriasis, eczema and other skin conditions may also cause onychorrhexis.
Other health conditions or diseases that may cause onychorrhexis include hypothyroidism, Raynaud's phenomenon, malnutrition or Sjogren-Larsson syndrome and other endocrine disorders that cause dry skin, states Medicine Online. Onychorrhexis is often the result of dryness in the nail. Some individuals are genetically predisposed to having dry nails, and this may worsen as the individual ages. Dry air and long, hot baths or showers also cause dry nails and eventually onychorrhexis.
Certain environmental factors or work hazards may increase an individual's chances of developing onychorrhexis, as noted by Medicine Online. These factors include windburn, sunburn, washing the hands frequently, prolonged exposure to cold, dry weather and excessive exposure to harsh chemicals, such as repeated use of nail polish remover. Repeatedly injuring the tips of nails may also cause them to become brittle.
There is no treatment for onychorrhexis, but moisturizing with a cosmetic or therapeutic cream, wearing protective gloves, avoiding exposure to certain chemicals and avoiding prolonged exposure to water may help prevent nails from becoming brittle, according to Medicine Online.