CLAIM: Magnetic fluctuations caused by solar flares, known as "geomagnetic storms", cause health problems in humans.
Several studies have come out in an field known as "heliobiology":
Abdullrahman HM, Marwa AM. The Effects of Solar Activity and Geomagnetic Disturbance on Human Health. 2020 - 2(4) OAJBS.ID.000203.
Heliobiology is a new branch of science that deals with the influences on human health caused by solar activity and investigates the possible mechanisms to explain the reported associations. In the last decades, many researchers have considered geomagnetic storms, cosmic rays, and solar flares to be hazardous to human health.
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Solar activity may contribute to the development of and be a trigger of the exacerbation of nervous and mental disorders, such schizophrenia, Alzheimer's disease, and multiple sclerosis [38].
Alabdulgader A, McCraty R, Atkinson M, Dobyns Y, Vainoras A, Ragulskis M, Stolc V. Long-Term Study of Heart Rate Variability Responses to Changes in the Solar and Geomagnetic Environment. Sci Rep. 2018 Feb 8;8(1):2663. doi: 10.1038/s41598-018-20932-x. PMID: 29422633; PMCID: PMC5805718
BMC's On Health blog, September 2019
This release of high energy magnetic varies according to the 11-year solar cycles, and is more intense during solar maxima periods. These periods are also characterized by a high number of geomagnetic storms (GMD) that have been linked to numerous health outcomes, including cardiovascular diseases (CVD), neurological system diseases, behavioral diseases, and total deaths.)
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Our results may be explained through the direct impact of environmental electric and magnetic fields produced during GMD on the human autonomic nervous system. Interactions between GMD and the autonomic nervous system are likely to induce a cascade of reactions in the body's electrophysiology that culminate in the collapse of organ functions and death.''
New Scientist, April 2008 Geomagnetic storms and suicides.
Geo-Magnetic Storm Wikipedia page
There is a large but controversial body of scientific literature on connections between geomagnetic storms and human health. This began with Russian papers, and the subject was subsequently studied by Western scientists. Theories for the cause include the involvement of cryptochrome, melatonin, the pineal gland, and the circadian rhythm.
Solar storms may cause up to 5500 heart-related deaths in a given year, New Scientist, June 2022.
What are the evidences of solar activity influence on coronary heart disease?, 40th COSPAR Scientific Assembly. Held 2-10 August 2014, in Moscow, Russia, Abstract id. F5.5-14-14.
It was shown statistically that during geomagnetic disturbances the frequency of myocardial infarction and brain stroke cases increased on the average by a factor of two in comparison with quiet geomagnetic conditions.
Some sources cast doubt on the claims in these studies:
Solar Flares: Effects on Humans, Aug 2023.
Dr. Gary doubted the connections between solar flares and human health. "The change in the magnetic field we're talking about is really small. If you think of the magnetic field that causes your compass needle to point north, we're talking about a 10th of a percent of that fluctuation," explained Dr. Gary.
Question - is there any legitimacy to these claims?