A growing body of evidence has suggested that selenium is important for the brain, as the turnover rate of neurotransmitters is altered in selenium deficiency.
While the benefits of selenium supplementation on some neurodegenerative diseases such as epileptic seizure and cognitive disorder have been established, its effect on migraine remains unclear.
To investigate the effect of selenium supplementation on oxidative stress and migraine symptoms, researchers in Iran conducted a double-blinded randomised clinical trial last year.
A total of 72 participants, who were aged between 18 and 65 years and clinically diagnosed with migraine, were randomly assigned to the intervention and placebo group.
The selenium group received tablets each containing 200μg of selenomethionine prepared by Tehran-based pharmaceutical company Pourateb, while the placebo group received tablets each containing 200μg of starch prepared by Isfahan University of Medical Sciences in Iran, which supported this study through a grant.
The participants took one tablet per day for 12 weeks.
It was found that selenium supplementation resulted in a significant reduction in nitric oxide (NO) levels (p = 0.03), and a significant increase in serum total antioxidant capacity (TAC) (p = 0.01), compared to the placebo group.
The selenium group also had a significant protective effect against malondialdehyde (MDA) levels, compared to placebo (p = 0.03).
Furthermore, selenium intake was associated with a lower frequency (p < 0.001) and lower severity (p = 0.01) of headache.
Based on Headache Impact Test-6 (HIT-6) scores, the selenium group showed a significant beneficial effect on quality of life, in comparison with the placebo group (p = 0.01).
There were no significant differences in blood pressure and anthropometric indices between both groups.
“In our study, selenium supplementation improved markers of oxidative stress, including NO, MDA and TAC levels, in patients with migraine. However, no favourable effect was observed on total oxidant status (TOS) levels.
“Our findings are in line with a previous study, in which lower selenium levels in people with migraine were positively associated with MDA levels and the incidence of migraine attacks,” the researchers wrote.
Impact of oxidative stress
According to the researchers, migraine is a neurological disorder with a prevalence of 14 to 15% worldwide and 15.1% in Iran.
The inefficacy and potential side effects of existing pharmacotherapies have called for safe alternative approaches for the management of migraine and improvement of sufferers’ quality of life.
Selenium is an essential component of selenoproteins and antioxidant enzymes, which have drawn particular interest for their key role in neurological health.
At the same time, increasing evidence indicate that oxidative stress is involved in the pathogenesis of migraine.
For instance, NO level is increased in the platelets, urine, and plasma of patients with migraine, playing a part in trigeminovascular inflammation and accelerating pain in the central nervous system.
Elevated levels of lipid peroxidation metabolites such as MDA have also been observed in migraine patients during headache attacks.
In addition, low activity of glutathione peroxidase, a selenium-dependent enzyme family whose main role is to protect against oxidative damage, is documented in people with migraine.
Therefore, improvements in the frequency and severity of headaches following selenium supplementation can be explained by the alleviation of neurogenic inflammation and oxidative stress.
Although this study did not find any significant effect of selenium on headache duration, previous studies have shown that it has a late response to interventions.
“A longer period of selenium treatment and with higher doses may affect the duration of headaches in migraine sufferers. It is also possible that reporting bias is higher in headache duration than headache frequency.”
It should be noted that the study has several limitations, including the small sample size as well as the lack of measurements or data on serum levels of selenium, inflammatory biomarkers, other oxidative stress indicators, and the extent of selenium deficiency in participants.
Further large-scale studies to conduct subgroup analyses based on factors such as sex and types of migraine, and to adjust for more confounders like medications, supplements and physical activity, are required to confirm the present findings.
Source: Frontiers in Nutrition
https://doi.org/10.3389/fnut.2024.1369373
“The effect of selenium supplementation on oxidative stress, clinical and physiological symptoms in patients with migraine: a double-blinded randomized clinical trial”
Authors: Arghavan Balali, et al
