A growing body of research has shown that headaches, especially tension headaches, can be linked to a deficiency of vitamin D in men. The latest study linking the headaches and low levels of vitamin D has been the largest study yet, and was conducted at University of Eastern Finland. Approximately 2,600 men between the ages of 42 and 60 took part in the study, and were researched over a period of 5 years. Around 68% of the men fell into the category of low vitamin D with 50 nanomoles per liter or lower, which is the threshold for deficiency. Out of these, 250 men suffered from chronic headache at least once a week, and those reporting more frequent headaches had lower vitamin D levels when compared to the rest of the sample. The study also divided the sample into 4 groups based on their vitamin D levels. The group with the lowest levels had a twofold risk of developing chronic headaches when compared to the group with the highest levels of vitamin D. It was also seen that the headaches occurred more frequently in the winter over the summer, which could be due to reduced exposure to sunlight that is needed for the body to produce vitamin D. This study doesn’t establish a cause-and-effect relationship between headaches and vitamin D deficiency, but rather draws an association between the two.
In the past, a similar study was published by two researchers from India in the journal Headaches. The study had a small sample – about 8 men, who suffered from chronic tension type headaches. All the subjects had very low levels of vitamin D and had little to no relief after taking medications to control the pain. All 8 patients were given supplements for vitamin D and calcium, and began to gain relief from their headaches in a few weeks. The researchers believed that the vitamin D, and not the calcium, was responsible for the relief in the headaches. It takes around a week for the calcium levels to return to normal in their body, and around 5 to 6 weeks for the vitamin D levels to return to normal, and headache relief came about only after 4 weeks or more.
Another study published in the The Journal of Headache and Pain found that the prevalence of headaches, both migraine and tension type, increased in the areas that moved away from the equator. Since moving closer to the southern and northern hemispheres causes less intense and a shorter duration of sunlight, it also causes lower absorption of the sunlight to produce Vitamin D. This can be tied to the findings of the study at University of Finland, where there was increased frequency of the headaches in the subjects during winters.
Finally, a study conducted at Cincinnati Children’s Hospital found that children and young adults suffering from chronic migraine headaches had deficiencies in vitamin D, riboflavin and coenzyme Q 10, which is a vitamin-like substance that was needed to produce energy for cell-growth and maintenance. However, the study couldn’t link the vitamin deficiency to headache relief because the subjects were given both vitamin supplements and medications to target the migraines, and there was no conclusive link between the increase in vitamins and lower headache frequencies. The study did find that boys and young men were more likely than girls to have vitamin D deficiency.
All these studies have helped to draw the correlation between vitamin D deficiency and chronic headaches, but more studies, especially large and randomized controlled trials, are needed to conclusively draw a strong relationship between the two. Moreover, most of the studies have showed the impact of vitamin D deficiency on male subjects, but there have been no studies exploring the same thing with women.