A man had severe, day-long migraines for 12 years and nothing worked. His doctors say they vanished after they prescribed leafy greens and cutting out red meat.

• A scientific paper described a man plagued by migraines that abruptly went away.
• The 60-year-old stopped having debilitating headaches after swapping diets, it said.

A 60-year-old man who suffered 12 years of severe migraines stopped experiencing them within three months of switching to a diet rich in leafy greens.

The patient, who had severe migraines for over 12 years, has been headache-free for over seven years, according to a case study published Thursday by BMJ Case Reports.

The authors of the study said the man exhibited the longest documented case of a chronic migraine being resolved after a change in diet.

Based on just one case study, it is impossible to conclude that a change in diet could cure chronic migraines. There were also other factors that could have influenced this patient's symptoms, including his being HIV positive.

Patients sometimes track "trigger" foods to try to minimize headache intensity. But so far there is no conclusive link between migraines and particular foods, according to the Migraine Research Foundation.

The patient, who was unnamed, had more frequent migraines in the six months leading up to a clinic visit, per the study. He reported having six to eight migraines a month.

In a short testimonial included in the case report, he said that the migraines were "debilitating," with some lasting up to 72 hours.

The migraines would get so bad that he "could end up in bed in the fetal position," he said. When the migraines didn't come, he would spend days in recovery, which made his job as a photographer "almost impossible," he said.

After the migraines stopped, he said: "I am no longer a prisoner in my own body. I have my life back."

The patient was advised to follow these recommendations:

• eating at least five ounces of raw or cooked dark green leafy vegetables like spinach, kale, and watercress every day.
• drinking one 32-ounce daily green smoothie daily.
• limiting intake of whole grains, starchy vegetables, oils, and animal protein, particularly dairy and red meat.

Although the scientists didn't have the ability to control whether he followed the diet to the letter, the patient kept a food diary.

After the switch, the patient even stopped taking his migraine medication, per the study.

The patient had tried other lifestyle interventions and medication, including eliminating chocolate, cheese, nuts, caffeine, and dried fruit, which he had identified as potential "triggers," the study said.

None of these interventions had worked, per the study

According to the American Migraine Foundation, studies have shown that migraines are a genetic disorder, but that lifestyle, diet, and environmental cues can play "a large part" in how often a patient gets a migraine.

The foundation warned patients to "be careful" when trying extremely strict diets that could lead to nutrient deficiencies.

The authors of the case study offer a potential mechanism for the effect: The leafy greens are rich in beta-carotene and other nutrients which they said in the study can have anti-inflammatory properties.

Although the man already ate a balanced diet, the inclusion of leafy greens increased his serum level of beta-carotene, the study reported.

It is unclear whether their theory for what might have caused the change is correct. Other factors could explain the change in symptoms beyond the diet. For instance, the man is HIV positive which has been linked to a heightened risk of migraines, the authors said in the study.

The man's allergies also improved after he changed in diet, which could be related, per the study authors.

According to David M Dunaief, a New York expert in nutritional medicine and lifestyle interventions who was an author of the study, "several" other patients, whose names were not disclosed, saw their migraines become less frequent within three months of changing their diet.