Melasma is not contagious and cannot be spread by touching, so there's no need to worry about infecting your friends and family. However, you can develop more patches of melasma for multiple reasons, particularly if you continue to expose your skin to the sun without protection.
In order to prevent the spreading of melasma, you should limit your time in the sun. The sun's rays are at their strongest between 10 a.m. and 4 p.m. -- even on cloudy days -- so try to avoid sun exposure during these hours. If you have to be out in the sun, wear light but protective clothing that covers your arms and legs, and try a wide-brimmed hat to protect your face. You should use sunscreen that has a sun protection factor (SPF) of at least 15, and protects against both UVA and UVB rays [source: DermNet New Zealand]. Remember to reapply sunscreen every two hours, especially after swimming or activities that make you perspire.
As mentioned before, skin products that irritate the skin can make your melasma worse and cause the patches to increase or enlarge. So be cautious of what you include in your skin care regimen.
Another way to prevent and stop the spreading of melasma is to eat foods that are high in folic acid. Some studies link hyperpigmentation to a deficiency of this important nutrient [source: What to Expect.com]. Foods that are high in folic acid include green leafy vegetables, citrus fruits such as oranges and anything with whole wheat or whole grains. Drinking a glass of orange juice in the morning, for example, could be a great defense against the spread of this skin condition.
Foods that are high in folic acid are also the foods that doctors recommend to pregnant women for preventing melasma and the spread of melasma. To find out more about the connection between melasma and pregnancy, read on.