Why Hair Gets Frizzy When It's Humid

One of the most common complaints women have with their hair is frizziness, which is particularly a problem in hot, humid weather. Just as there are scientific reasons behind the frizz, there are also effective ways to combat the problem.

History

In 1783, Horace Benedict Saussure discovered that the length of human hair changes according to levels of humidity. He invented a hygrometer, a device to measure humidity in the air, which used strands of human or horse hair with the oils removed attached to levers that magnified a small change in hair length.

Definition

Hair is made up of tiny molecules, mostly of a hard fibrous type of protein called cytokeratin. In between these molecules lie spaces in which humidity can get trapped. One of the reasons hair is curly or frizzy is because hydrogen bonds between the keratin proteins are weak and can be enhanced by the trapped water. The products you buy in a store to straighten your hair work because they keep moisture from penetrating the hair strands.

Considerations

Alan Bauman, a national hair expert who has appeared on the Today Show, Good Morning America and in "Newsweek," says that frizzy hair can also be caused by a combination of damaged hair strands and static, or a high negative charge on the hair. Hair gets damaged from rough brushing or combing, harsh shampoos and chemical processing, as well as high heat from blow dryers and straighteners. Static, on the other hand, is caused by shampoos, when negative charges in the keratin protein in hair and the shampoos repel each other, leading to frizziness.

Prevention/Solution

"Style Hair Magazine" recommends getting plenty of hair friendly nutrition from food and supplements that include omega-3 essential fatty acids, evening primrose oil, lecithin, silica, biotin, pantothenic acid and protein. Other preventative measures include using a hat, bandanna or scarf to shield your hair from the harsh effects of sun and wind; avoiding any type of friction on your hair, as well as alcohol-based hair products; avoiding heat; and getting a regular trim. To treat frizzy hair, use a cool rinse with water or a mixture of vinegar and water and use a hand towel and squeeze the hair up from ends to roots, avoiding rubbing, followed by an anti-humectant hair pomade.

Warning

Although most frizzy hair is the result of humidity or harsh treatment of hair, there are some medical conditions that can cause brittle or kinky hair, such as the various thyroid diseases like hyperthyroidism, hypothyroidism, Hashimoto's thyroiditis and Graves disease; the inherited condition incontinentia pigmenti; the skin and tissue disorder myxedema; and Menkes syndrome, a metabolic disorder in which cells in the body cannot absorb enough copper. Any sudden changes in hair frizziness should be checked out by your doctor.