Estrogen causes increased production of melanin stimulating hormone or MSH. Usually, increased production of MSH increases pigmentation evenly, but in some cases, the melanin is secreted in clumps. The spot may fade over time, as would a tan or any other increase in pigmentation, but there are some things that you can do to naturally speed the process.

If you are an older woman using hormone replacement therapy to relieve menopausal symptoms, estrogen could again be the cause. But, in most cases what causes age spots is exposure to the sun. Usually a sun burn is involved, but not always. It really depends on how much exposure you get on a regular basis, how light your complexion is and how many times the area has been burned in the past.

Dermatologists refer to them as lentigos. They occur most frequently on the backs of the hands and the face. Men that are bald frequently see them on their heads, unless they are careful to wear a hat. Actually, wearing a wide-brimmed hat is one of the best things that you can do to protect your skin from sun exposure.

Many experts say that sun exposure is the cause of most of the signs of aging. But, the problem is actually the molecular damage that is triggered by overexposure to the sun.

The body looks at UV radiation as a threat. The immune system kicks into high gear. It only has so many defenses against outside threats. One is free radicals.

Free radical damage is probably what causes age spots, but no one is sure. It hasn't been a subject of great study. Researchers are more concerned about cancer, for obvious reasons. Although free radicals can eventually damage the cellular membranes and cause DNA and collagen degeneration, they also kill intracellular bacteria. When the threat of UV radiation is felt, free radical production increases, even though the threat is not bacteria.

The body is a complex piece of machinery, but it is also simple. It responds to any unknown substance in the same way. Increase free radical molecules, secrete inflammatory molecules and send in antioxidants. Free radicals and inflammatory molecules cause damage. Antioxidants prevent it.

We do know that what causes age spots is melanin clumping. It's just that no one is sure why it clumps like that. Melanin is normally produced as another defense mechanism. Melanin rich cells in the epidermis turn UV radiation into heat, which is non-threatening and does not trigger immune system responses.

Melanin is responsible for the skin's complexion. People with darker complexions rarely develop skin cancer. So, in effect, melanin provides protection against skin cancer. Before you make an effort to inhibit melanin production, you should seriously consider what that melanin is doing for you.

Now, that you know a little more about what causes age spots, you might want to learn about how to prevent them and what you can do to fade them, without risking your skin's health.