Head lice infestations are a common concern. These tiny insects and their eggs, known as nits, can be hard to spot, leading to misconceptions. One common misunderstanding is that nits are black. In reality, nits are not black; they appear in lighter shades, ranging from translucent to various tones of brown.
What Nits Actually Look Like
Viable nits, which are head lice eggs, are small, about the size of a pinhead. They are oval or teardrop-shaped. Their color can vary, appearing translucent, yellowish, tan, or light brown. As they mature, living nits may darken to brown.
Nits are laid by female lice and are firmly glued to individual hair shafts, very close to the scalp. This close proximity provides the necessary warmth for them to incubate and hatch. The strong, cement-like substance makes them difficult to remove. After hatching, the empty nit shell remains attached to the hair shaft, appearing white or clear.
Distinguishing Nits from Other Things
Nits are often mistaken for other substances in hair, such as dandruff, dry skin flakes, or hair product residue. A key difference is their adherence: nits are firmly attached and will not easily flake off or be brushed away. In contrast, dandruff flakes are loose and easily removed.
Hair product residue or other debris may resemble nits, but these slide along the hair shaft or can be flicked off easily. Nits, due to their strong adhesive, require effort to pull off the hair. Their consistent oval or teardrop shape also helps differentiate them from irregularly shaped flakes or product buildup. If a speck can be easily moved or flicked away, it is likely not a nit.
The Head Lice Lifecycle
The head lice lifecycle consists of three main stages: the egg (nit), the nymph, and the adult louse. Female adult lice lay nits near the base of the hair shaft, where the temperature is optimal for their development.
Nits hatch into nymphs within 6 to 9 days. A nymph is an immature louse that resembles an adult louse but is smaller, about the size of a pinhead. Nymphs mature into adult lice approximately 7 to 12 days after hatching. Adult lice can live for up to 30 days on a person’s head and can lay several eggs per day, continuing the cycle. Empty nit casings, the remaining shells after hatching, stay attached to the hair as it grows, indicating past infestation.