Heavy migraines can be debilitating, but a new study shows that a low-carb diet could be the answer to avoiding crushing headaches that come with them.

Researchers in Italy tested volunteers on a high-fat, low-carb 'ketogenic diet' – which forces the body to burn fats rather than carbohydrates – and found it "significantly reduced" the number of headaches within the first month.

By cutting down on carbs, this diet prompts the body to produce ketone bodies for its fuel – water-soluble molecules that are less demanding and less inflammatory than the glucose that's normally created – and the scientists think this could be why there's a big reduction in migraines.

"Our hypothesis is that the combination of ketone bodies and changed glucose response could lead to the outstanding therapeutic effect we have observed in our patients," lead researcher Cherubino di Lorenzo from the University of Rome told Danielle Bengsch at ResearchGate.

A total of 96 women were involved in the six-month study, all of whom suffered from migraines and were already seeing a dietician to help lose weight.

Of the group, 45 followed a very-low-calorie ketogenic diet for a month, then switched to a standard low-calorie one. The others kept to a standard diet for the whole time.

Both groups saw a drop in the frequency of their headaches, but it was much greater for those on the ketogenic diet. When these women switched to the standard low-calorie diet, the number of migraines increased – though they were still happening less often than before the study started.

After just one month, those on a ketogenic diet were averaging 0.91 days with a headache per month, compared with 5.11 days before treatment started. Attacks happened less often, and were shorter, too.

This ketogenic diet isn't new – it's previously been used to treat epilepsy in children and to help with weight loss. Di Lorenzo and his team were alerted to its potential migraine-busting properties after they noticed it reducing headaches in twin sisters in a separate study.

In addition to changing the body's fuel production process, the ketogenic diet and forces the body to work more efficiently, with less oxidative stress on cells (brought on by free radicals). It also cuts down on sterile inflammation – a potentially harmful type of inflammation that's been linked to migraines.

Experts describe the ketogenic diet as a little bit like kicking the body into a mild starvation mode, and getting it to reassign its resources to suit. That means it allows much faster access to the body's fat reserves.

There are potential side effects to consider, such as fatigue and nausea.

Despite the link between ketone bodies and reduced migraines in this study, the researchers say more research is needed, as there could be other factors at play in the chemical reactions that the diet induces in the body.

"We have hypothesised that several interacting mechanisms may be at work in the clinical and neurophysiological actions of the ketogenic diet," the researchers explain in the European Journal of Neurology.

Of course, while we wait for more studies to appear, any kind of relief would be welcome for the billion or so people who experience migraines worldwide. And Di Lorenzo says that for overweight migraine sufferers, it's worth exploring – but always consult your doctor first.