Have you ever wondered why influenza has such a defined season?
Historically, the flu and other respiratory illnesses thrive during the darker months of the year, when days are shorter and exposure to sunlight is limited. However, recent research is reviving what doctors of the past already suspected: sunlight not only boosts our mood but also plays a crucial role in preventing and mitigating influenza.
The Role of Sunlight in Immune Health
Sunlight exposure activates the production of vitamin D, a vital nutrient for strengthening immune cells like macrophages and T-cells, which are essential for fighting viral infections. While vitamin D supplements are helpful, studies indicate that direct sunlight exposure has a broader impact on community health by promoting collective immunity (1).
Recent studies, such as the one published by David Slusky and Richard Zeckhauser in the NBER Working Paper Series, demonstrate that a 10% increase in sunlight exposure during the months leading up to an influenza outbreak can significantly reduce the incidence of the disease (2).
Beyond vitamin D, sunlight also generates other protective effects. According to experts, near infrared radiation (NIR) and ultraviolet (UV) light directly help neutralize viruses and strengthen the body’s immune responses.
Why Influenza Surges in Winter
During colder months, people tend to spend more time indoors, reducing their sunlight exposure and increasing close contact, which facilitates the spread of viruses. Additionally, lower relative humidity levels during winter allow the influenza virus to survive longer in the environment.
Interestingly, in Australia, the influenza season peaks in July, precisely when days are shortest in the southern hemisphere. Coincidence?
The Historical Benefits of Sunlight in Medicine
The therapeutic use of sunlight is not new. Nineteenth-century doctors used to bring their patients outdoors to accelerate recovery from respiratory illnesses; this knowledge, now backed by modern research, underscores the importance of integrating sunlight exposure into our health strategies.
Unfortunately, this practice has largely been abandoned, as it is not something currently taught in medical schools.
Sunlight: Trump’s Controversial Proposal During the Pandemic
During his first term, on April 23, 2020, President Donald Trump suggested during a White House briefing that sunlight might help COVID-19 patients recover faster. In his words, Trump stated:
“There’s been a rumor that, you know, a very nice rumor, that you go outside in the sun or you have heat and it does have an effect on other viruses”
He then asked Dr. Deborah Birx, the Coronavirus Task Force Coordinator, whether she had heard of this type of therapy involving sunlight for viruses. Dr. Birx responded, “Not as a treatment.”
Trump later requested Dr. Birx to investigate whether there was any way to apply light and heat as a treatment for the virus, saying: “I would like you to speak to the medical doctors to see if there’s any way that you can apply light and heat to cure, you know, if you could. And maybe you can, maybe you can’t.”
As expected, this idea did not progress further, as medical experts lacked knowledge or training on the potential use of sunlight as an antiviral therapy. As noted earlier, today’s medical education does not include training in these unconventional approaches.
An Improvised and Poorly Supported Proposal
Trump, known for speaking freely and expressing his ideas without much filtering, raised these questions in a tone that reflected curiosity and openness to alternatives; However, this approach to addressing medical topics drew immediate criticism; Media outlets and health experts quickly ridiculed his comments, accusing him of spreading misinformation and mocking the idea of sunlight as a possible treatment for COVID-19. This backlash was further amplified when Trump mentioned using zinc supplements as a measure to strengthen the immune response against the virus.
Interestingly, Trump did not present his statements as absolute facts but as ideas worth exploring. Yet, the closed-minded stance of many experts and commentators, combined with their unwillingness to consider alternatives, sealed the fate of this discussion; Instead of critically analyzing his proposal, the predominant response was mockery and outright dismissal.
Where Did This Idea Originate?
The question remains: where did this notion come from in Trump’s thinking? It is possible that one of the medical professionals who have cared for his health and that of his family over the years shared this information with him.
As is known, there are health professionals who, beyond traditional approaches, actively investigate alternative therapies or practices that fall outside conventional medical norms; This could include knowledge of the beneficial effects of sunlight, partially supported by research showing how sun exposure can influence the immune system and overall health.
The Problem with Ignoring the Unconventional
This highlights a persistent divide between innovative ideas and traditional medical knowledge; As previously mentioned, modern medical education rarely includes training on therapies like phototherapy or the impact of sunlight on viruses such as influenza, despite historical practices and recent research suggesting potential benefits.
In Trump’s case, his improvised style and the lack of immediate scientific backing led to his ideas being dismissed without deeper analysis; However, this incident leaves an important lesson: while traditional knowledge is invaluable, unconventional ideas, when approached rigorously and without prejudice, can open new avenues in the quest for effective public health solutions.
Even at the prestigious Harvard University, after reviewing the existing medical literature, researchers concluded: “We found that sunlight strongly protects against influenza.” (3) This statement not only provides scientific support for what the U.S. president already intuited but also opens the door to reflect on the potential benefits of sunlight in combating other diseases like COVID-19, even though no specific studies exist yet.
What becomes clear is that the positive effects of sunlight are not just a simple rumor but a reality founded on solid research; It was worth exploring its potential as a natural ally against respiratory illnesses.
Practical Recommendations for Harnessing Sunlight
- Regular Sun Exposure: Spend 15 to 30 minutes daily in direct sunlight on your arms and face, especially during peak hours (10:00 AM to 3:00 PM); Adjust this time and schedule based on your skin tone and geographic location.
- Alternatives in Winter: During shorter days, consider using UV light lamps designed for light therapy or consuming vitamin D-rich foods such as fish and egg yolks.
- Hygiene and Open Spaces: Whenever possible, engage in outdoor activities to combine the benefits of sunlight with a reduced likelihood of close contact with sick individuals.
Conclusion
The sun, a natural and free source of health, has the potential to be a crucial ally against influenza and other respiratory illnesses. While scientific advancements have provided modern solutions like vaccines and antivirals, we must not underestimate the power of such an accessible and effective tool as sunlight; Let us reclaim this ancestral knowledge and make sunlight an essential component of our daily health practices.
