The Effects of Sunlight on Human Immunity

Researchers continue to unravel the sweeping and essential impacts sunlight has on our ability to fight disease
August 24, 2020 Updated: August 24, 2020

Many believe that sunlight exposure has mainly harmful effects, yet recent evidence suggests that sunlight can improve immune function in multiple ways.

Beyond sunlight’s ability to help your skin generate vitamin D, which lets your body modulate the innate and adaptive immune responses, researchers have demonstrated that sunlight can improve the motility of infection-fighting immune cells and discourage the spread of pathogens in hospital environments.

Recent studies have indicated that sunlight exposure may have immunomodulatory effects and protect against infections, including acute respiratory infections such as influenza.

Additionally, studies have shown that high levels of solar ultraviolet radiation (UVR) exposure are associated with lowered rates of allergiesautoimmune diseases, and cancers. While these results are often attributed to increases in vitamin D, researchers have now demonstrated that sunlight exposure can improve immune function by improving the motility of killer T-cells.

In addition to these findings, researchers also point out that infectious outbreaks, including influenza, tend to happen more often during winter months when many people have little to no sunlight and UVR exposure.

Additional research from Columbia University suggests that UV light can kill even drug-resistant bacteria without inducing skin damage. Researchers believe there are two main facets that explain sunlight exposure’s effect on immune function: an increase in vitamin D levels and energized T-cells.

Increased Levels of Vitamin D

Sunlight exposure is widely known to increase vitamin D levels in your body. Skin cells absorb UVB radiation during skin exposure and convert it to vitamin D, which is metabolized in your liver and kidneys and used throughout your body to regulate calcium, increase beta-endorphins, and stimulate the immune system.

A deficiency of this important vitamin is linked to an increased risk of cancer, heart disease, obesity, depression, cognitive impairment, and bacterial and viral infections. Unlike other essential vitamins, since vitamin D is synthesized in your skin following UVB exposure, sunlight exposure is vital for improving vitamin D levels and subsequently improving immune function. If regular sunlight exposure isn’t possible due to your climate or lifestyle, vitamin D supplementation may be useful.

Energization of Infection-Fighting T-Cells

Sunlight, particularly blue light and UV light contained in solar rays, energizes T-cells by triggering the production of hydrogen peroxide in these cells, which enhances their motility in the skin and improves their infection-fighting capabilities.

Researchers theorize that the photosensitivity of T-cells may help to explain sunlight’s positive effect on immune function and suggest blue-light therapy as a possible therapy for immuno-compromised patients.

In addition to these immune-boosting effects, researchers have found that sunlight may reduce the risk of infection in health care environments, as the majority of airborne microbes that cause infection cannot tolerate sunlight and are especially susceptible to direct (rather than diffused) sunlight.

Sunlight helps to regulate biological rhythms, which researchers believe may enhance immune function. Additionally, they suggest that hospitals and health care facilities be designed to allow sunlight to reach occupants, as even sunlight through glass may discourage the survival and spread of pathogens.

Additional Benefits of Sunlight Exposure

Sunlight’s role helping the body produce vitamin D is critical because high levels of vitamin D have been found to improve inflammatory response, lower blood pressure, increase cognitive function, and lower the risk for certain cancers. Researchers estimate that sunlight exposure accounts for 90 percent of most individual’s vitamin D levels, so if you’re not getting much sunlight exposure, you’re likely deficient.

Sunlight has other impacts as well.

Skin Disorders

Various skin disorders, including eczema, psoriasis, acne, and pityriasis rosea, improve through regular sunlight exposure.

Melatonin Production

Sun exposure improves melatonin production, a pineal hormone responsible for triggering your body’s circadian rhythms and improving the quality of sleep. Melatonin also plays a key role in inflammation and infection and suppresses UVR-induced skin damage.

Weight Loss

Animal studies have found that ongoing, low-level exposure to UV radiation can reduce weight gain and improve cardiovascular health in subjects fed a high-fat diet, perhaps by reducing certain aspects of metabolic dysfunction.

Provides Emotional Health Benefits

Ongoing, low-level exposure to sunlight is associated with improved mental health. In various studies, participants with depression and seasonal affective disorder experienced improved moods after sunlight therapy. Additionally, researchers have demonstrated that increased levels of vitamin D can improve depression and other mental disorders.

Improves Cognitive Function

Recent studies have found a correlation between high levels of vitamin D and improved cognitive function.

Additionally, researchers have demonstrated that long-term, high levels of sun exposure are associated with better cognitive functioning, possibly because of the protective effect vitamin D has on brain cells and an increased production of serotonin and melatonin and improved circadian rhythms.

The potential for sunlight exposure therapy is vast, and it’s an affordable, natural, and easily attainable way to improve immune function while boasting a wide range of additional benefits. To learn more about sunlight exposure’s researched effects on cancer, psoriasis, cardiovascular disease, prenatal nutrition, mental disorders, skin care, and more, please visit the sunlight exposure research database at GreenMedInfo.com.

For hyperlinks to the studies mentioned in this article, please visit TheEpochTimes.com/c-wellness

The GMI Research Group is dedicated to investigating the most important health and environmental issues of the day. Special emphasis will be placed on environmental health. Our focused and deep research will explore the many ways in which the present condition of the human body directly reflects the true state of the ambient environment. This work is reproduced and distributed with the permission of GreenMedInfo LLC. Sign up for the newsletter.