Overweight and obese people are at higher-than-average risk of migraines, suggests a new study.
Researchers looking at so-called episodic migraines - headaches that occur less than every other day - found they were almost twice as common among obese people as among normal-weight adults.
"This suggests patients and doctors need to be aware that obesity is associated with an increased risk of episodic migraine and not wait until a patient has chronic migraine to address healthy lifestyle choices, such as diet and exercise, and to choose medications that impact weight with care," lead researcher Dr. Lee Peterlin, from Johns Hopkins University School of Medicine in Baltimore, told Reuters Health in an email.
However, the researchers couldn't be sure which came first - the extra weight or the headaches. And one migraine researcher not involved in the study said he would be cautious interpreting its findings.
"If this helps of course to make people believe they should lose weight, that's great, but does it mean that reduction in weight will reduce migraine attacks, or treat migraines? That's a question they haven't addressed," Dr. Tobias Kurth, of the French national research institute INSERM and the University of Bordeaux, said.
About 10 to 15 percent of people have episodic migraines, according to Peterlin.
Previous studies have linked obesity to chronic migraines, which by definition occur at least every other day. But there's less evidence on whether weight also plays a role in less frequent migraines, researchers said.
To try to answer that question, Peterlin and her colleagues analyzed data on 3,862 people who participated in a national U.S. survey in the early 2000s, including 188 who reported having migraines an average of three or four times each month.
About 32 percent of people with episodic migraines were obese, based on their self-reported height and weight, compared to 26 percent of non-migraine sufferers.
After accounting for other differences between people with and without migraines, such as their age and smoking rates, the researchers found that being obese was linked to an 81 percent higher chance of having episodic migraines, they reported Wednesday in Neurology.
The obesity-migraine link was stronger among women and people under 50 years old but less clear for men and older adults, who have lower migraine rates in general.
Peterlin said there are a few possible explanations for the association, including that the same systems in the body that are activated during a migraine help regulate how much people eat. Also, people who get regular migraines may be less active because of the pain or take medications that influence weight gain, she said.
Kurth, who wasn't involved in the new study, agreed lifestyle factors may play a role in both obesity and migraines. But he cautioned against drawing a direct link between weight and episodic migraines in the absence of more research.
"I'm just very careful, because I'm missing the big picture," he told Reuters Health.
"If obesity would cause migraine, which is the suggestion of this study, we would expect to see an increase … in the prevalence of migraine, because we have such an epidemic of obesity in the United States," he said. "And this is just not true."
However, Peterlin said, rates of the two conditions wouldn't necessarily be expected to go hand and hand on a larger scale - and that some studies have suggested episodic migraines are in fact becoming more common.