When hypopigmentation (not to be confused with hyperpigmentation) occurs, it causes patches of skin that are lighter than the rest. This can either be caused by a lack of melanocytes or lack of activity in the melanocytes. If your skin has no pigmentation at all it is referred to as de-pigmentation. The reduced pigment can cover the whole body or be localised to specific areas. Hypopigmentation or de-pigmentation is caused by genetics, burn injuries, chemical products, infections or diseases such as vitiligo.
This condition presents itself as small, irregularly placed patches on the skin. De-pigmentation is caused by the melanocytes being damaged, but it is still unclear as to why this is. More than half of all patients with vitiligo develop it before they turn 20. The condition is often hereditary. Vitiligo is often associated with alopecia areata (partial hair loss) hyperthyroidism (an overactive thyroid) and other metabolic disorders. Stress, severe sun damage or trauma to the skin can worsen the condition.
The most common places for vitiligo to show up on the body are in the face around the eyes, forehead, cheeks and chin. The skin issue tends to be permanent even if around ⅓ of people experience some form of pigment return to the affected areas. There is no effective treatment for this condition.
Stretch marks occur when the elastic tissue is stretched to the point of causing a break down of the tissue itself. They can occur during puberty, pregnancy or from sudden weight gain and is also common amongst bodybuilders. They most commonly appear on the hips, thighs, bottom, chest, over arms etc. When they are new they are red or violet/red but gradually fade to become white.
There is no successful treatment against striae but it is possible to help to prevent them by keeping your skin soft and elastic by massaging in body lotions and nourishing oils regularly into your skin.