People who suffer from migraines or other tension disorders are at greater risk of developing the thyroid condition known as hypothyroidism, a new study finds.

Hypothyroidism is a disorder that occurs when the body can’t make sufficient thyroid hormone causing individuals to suffer from mood swings, weight gain, hair loss, fatigue, constipation and, in women, irregular menstrual cycles.

University of Cincinnati researchers looked at 8,412 people enrolled in a medical monitoring project designed to examine health outcomes of residents living in Fernald, Ohio, which is located near a former uranium processing plant. They were followed for 12 years.

They found that people who suffered from migraines were at highest risk, but that that people with other headache disorders, including tension and cluster headaches, were also more likely to develop the thyroid condition.

People with migraines had an increased risk of 41 percent while others with tension headaches were at a 21 percent higher risk of developing hypothyroidism, compared to those who did not suffer from such headache disorders, the study says.

Previous research has shown that people who have headache disorders do have a higher risk of developing thyroid conditions, but this study was larger than others, and the people were followed for a longer period of years, the researchers say.

This study also found that female gender, increasing age, obesity and hypothyroid-inducing medications were associated with new onset hypothyroidism, which is consistent with previous research. The study also found that smoking was protective against hypothyroidism, which other research has found.

Radiation is a known risk factor for developing hypothyroidism, but no association of uranium exposure and thyroid disease was found in the Fernald study, the researchers added.

The researchers say the study, which appears in Headache: The Journal of Head and Face Pain, demonstrates that people who have headache disorders should be monitored for hypothyroidism.