Oman today_ The growth and appearance of nails can be influenced by age, medical conditions, and environmental factors. For example, in hyperthyroidism, nail growth tends to increase, whereas in hypothyroidism or febrile illnesses, nail growth slows down. In children, the nail plate is thinner and may sometimes appear spoon-shaped, especially on the big toes. Thumb-sucking in children under five can lead to horizontal cracks at the nail tip and inflammation along the nail edges. Additionally, in newborns, nails may slightly embed into the surrounding skin, which is a normal and temporary finding. Horizontal lines or shapes resembling a breastbone may also appear on nails during the first months of life.
As people age, nail growth slows down. Reduced blood circulation and repeated trauma, especially to toenails, can make the nail surface pale and dull. In older adults, white nails or longitudinal ridges are often observed. In individuals over 50, mild longitudinal lines on nails are generally considered normal.
The nail surface can also show various changes. Longitudinal grooves may run along the entire length of the nail or only part of it, and their depth can be superficial or complete. These lines can be hereditary or caused by skin conditions, rheumatoid arthritis, vascular problems, aging, warts, or nail tumors. Transverse grooves can also be superficial or deep, with internal or external causes, such as manicures, trauma, local inflammation, or systemic conditions like drug reactions or lung infections. These lines usually indicate a temporary disturbance in nail growth. Pitting, which appears as small depressions on the nail surface, can be deep or shallow, regular or irregular, and may result from trauma, psoriasis, or localized hair loss.
Some nails become rough and coarse, potentially affecting all nails. This is most commonly associated with localized hair loss, psoriasis, or lichen planus. In children, this condition can occur as well and usually resolves spontaneously. Irregular or layered fractures at the free edge of the nail mostly respond to topical care and moisturizers and are not strongly linked to systemic diseases. An increase in nail pits or lines may be seen in rheumatoid arthritis, with oral itraconazole use, or as part of aging. It is important to note that nails naturally have lines and points, and determining whether these changes are pathological requires evaluation by a medical professional.
Nail color can also change. Sometimes, pigments come from external sources and appear on the nail surface, such as discoloration from smoking. Identifying pigments beneath the nail can be more challenging and may be due to microbial infections, such as Pseudomonas. Internal color changes are also significant; in fair-skinned individuals, longitudinal lines caused by melanin deposition should be evaluated, while in dark-skinned individuals, this is usually normal. Pigment deposition can also result from heavy metals or medications, such as gray discoloration from silver. White nails, or leukonychia, are common and can result from anemia, vascular disorders, damage to the nail matrix, hereditary factors, or systemic diseases. In some cases, white lines or spots may be related to infections, chemotherapy, toxins, trauma (e.g., manicure), or localized hair loss.