Health benefits of vitamin D and exposure to sunlight

sunshine vitamin

The sun is essential to our health, strength, peace of mind, and even our survival. Our bodies have evolved to harness the power of the sun to produce hormones that act as pain relievers, anti-inflammatory agents, appetite regulators and other factors that keep every aspect of our bodies functioning properly. 

Vitamin D3 is one of the most well-known hormones produced by sunlight. Although called a vitamin, vitamin D actually acts as a hormone within the body. Vitamin D production occurs naturally in the body when UVB light hits the skin and converts specialized cholesterol into vitamin D3. Vitamin D3 converts to vitamin D3 in the skin and passes into the bloodstream over several days. After reaching the liver, vitamin D requires two conversions in metabolism to become calcitriol, which is the active form of vitamin D. Calcitriol binds to vitamin D receptors in nearly every cell throughout the body. This process is regulated by the body and bioavailability is managed by several internal control mechanisms that enhance efficiency when vitamin D levels are low and reduce it when levels are high to prevent toxicity.

lack of sunlight 

The spectrum of sunlight spans over 2,000 nanometers, but surprisingly a small portion of that spectrum provides most of the benefits we receive from it. We call this little slice of sunlight, the “spectrum of life.” Without this specific wavelength, our immune system malfunctions, we become susceptible to disease, our bones become weak and we begin to break down on almost every level. 

During the past 150 years, humans have rapidly transitioned from an agricultural society to an industrial society to the information age. For the first time in human history, we do not receive the abundance of natural sunlight that we are used to when we work and play outside. Indoor activities that often revolve around a computer screen dominate the modern lifestyle of work and recreation. When humans were hunters and hunters, we had no problem getting time in the sun, but our current lifestyle doesn’t allow us enough sun exposure to stay healthy. 

Even when we go out, we now cover ourselves with protective clothing or sunscreen in an effort to prevent sunburn, skin cancer, and premature skin aging. These measures inhibit the production of vitamin D3 and other beneficial light products. Studies have shown that vitamin D deficiency is a global concern, with approximately 77% of the world’s population having low levels of vitamin D. It creates and thus combats many diseases on a global scale that are directly affected by lack of exposure to sunlight. 

Is sunlight good for you?

A large body of research demonstrates the importance of sunlight to support health. Studies have shown a relationship between lack of sunlight and the occurrence of several chronic health problems: 

• Several studies have shown a lower incidence of multiple sclerosis and type 1 diabetes with increased exposure to sunlight.

• Heart disease is the leading cause of death in the United States and increased sun exposure is associated with decreased cardiovascular risk factors such as high blood pressure.

• Cardiovascular complications and related death occur significantly more in winter than in summer.

• Cancer is the second leading cause of death in the United States, and several studies have found that increased exposure to sunlight is associated with a lower incidence and mortality from multiple forms of cancer.

Autoimmune, neuromuscular and skeletal diseases, cardiovascular disease, hypertension, and common cancers have all been linked to a lack of exposure to sunlight and vitamin D. 

A 20-year study of 29,518 people found that those who avoided sun exposure were twice as likely to die from all causes. This research corroborates several previous studies from around the world demonstrating that reduced sun exposure is a risk factor for all-cause mortality. 

Not only is lack of sunlight associated with a fatal disease, but it is also associated with many diseases that dramatically reduce quality of life. Depression, symptoms of bipolar disorder, suicide rate, and decreased cognitive performance are associated with winter, increased distance from the equator, and decreased exposure to sunlight. Sunlight prevents rickets, and as we age, it becomes even more important for healthy bone health to prevent osteoporosis and bone fractures. All these studies point to the importance of sunlight to humans and the extent to which the sun contributes to our health and happiness. 

Positive effects of the sun

When human skin is exposed to sunlight, it produces many hormones and peptides that contribute to overall health and wellness. Substances made from chemical reactions with sunlight are called photovoltaic products. While vitamin D is the most universally recognized health benefit that humans receive from exposure to sunlight, it is just one of many important photosynthesis products. 

Some healthy photovoltaic products all made in the same ultraviolet B (UVB) wavelength range include: 

Vitamin D3  has a wide-ranging effect on the soft and hard tissues of the body. It affects the musculoskeletal, cardiovascular, nervous and immune systems. 

Calcitonin Gene-Related Peptide (CGRP) –  Reduces high blood pressure, reduces inflammation and regulates the immune system. 

Neuropeptide Substance P (SP) –  Promotes healthy blood flow and regulates the immune system. 

Adrenocorticotropic hormone (ACTH) –  reduces inflammation and regulates the immune system. 

Melanocyte-stimulating hormone (MSH) –  reduces inflammation and increases sexual desire. 

Calcitriol-  regulates cellular function and is involved in all major body systems. 

Beta Endorphin (BE) –  Increases relaxation, acts as a natural pain reliever and promotes feelings of well-being. 

All of these substances contribute to the feeling of relaxation and happiness that we experience when we are regularly exposed to the sun. Like other animals, humans have developed an internal reward system to promote biologically beneficial activities that increase the chance of survival. The reward system uses beta-endorphins to make us feel good, reduce pain, and encourage behavior that increases our survival potential. Nature promotes sun-seeking behaviour, so we continue to have these UV-combined photovoltaic products that keep us healthy. 

Is sunbathing good for you?

While there are many health benefits of sunlight, the sun also has the potential to cause damage. Moderate exposure to sunlight is needed to achieve many of the health benefits that the sun provides, but it can be difficult to manage. Excessive exposure to the sun can lead to sunburn and is linked to skin cancer. 

Light can be divided into many different wavelength ranges. Different wavelengths of light lead to different physiological processes occurring in the body. The light in the UV spectrum can be further divided into UVA, UVB, and UVC. UVA light has the longest wavelength at 320-400 nm. UVB light has a wavelength between 280-320 nanometers. About 95% of UVB light is absorbed by the ozone layer. UVC light has a wavelength between 100 and 280 nm which is very harmful to human skin. Fortunately, the Earth’s atmosphere absorbs the UV spectrum almost completely. 

The majority of skin-related benefits from sunlight stem from the UV spectrum. It is this light spectrum that stimulates the production of vitamin D in the skin.

While sunbathing can stimulate the production of vitamin D and other important hormones, it also exposes you to UVA rays that can cause skin damage. Tanning occurs when UVA rays stimulate melanocytes to produce melanin, the brown pigment that leads to tanning. These UVA rays damage the deeper layers of the skin which can lead to premature skin aging and skin cancer.

How much sunlight do you need per day?

People with fair skin types need 10-20 minutes of sun exposure several days a week without sunscreen in order to maintain high vitamin D levels and support health. People with darker skin types will need more time in the sun per day in order to get the same effect and should approach 30 minutes. Exposure to the sun to stimulate vitamin D production should not cause sunburn. If you suffer from a sunburn, it is a sign that you have spent too much time in the sun and have reached the point of causing skin damage. 

How much sun exposure is needed for vitamin D?

When it comes to making vitamin D from the sun, one of the most frequently asked questions is, “How much vitamin D do you get from the sun?” The answer will be slightly different from person to person. Skin tone, starting vitamin D level, and other factors affect how much vitamin D a person will get from exposure to sunlight. Studies have shown that full-body sun exposure that causes a slight pink color after 24 hours has the ability to stimulate between 15,000 and 20,000 IU of vitamin D production in the body. This indicates that the human body has the ability to produce large amounts of vitamin D from light with minimal time spent in the sun. Using light to make vitamin D allows your body to self-regulate vitamin D production and make what it needs to stay healthy, without the risk of overdose or toxicity.

It can be difficult naturally to get enough sun exposure and absorb vitamin D to support health. In order to get Vitamin D from the sun, we must expose our skin to direct sunlight when the weather and geographic conditions are absolutely perfect. Many factors limit our ability to produce vitamin D from sunlight, including latitude, season, time of day, cloud cover, altitude, use of sunscreen, and pollution. In northern climates, vitamin D cannot be obtained from the sun in winter. Between November and March, the angle of the sun prevents the majority of ultraviolet B (UVB) light from passing through the atmosphere, and thus from reaching our skin to stimulate vitamin D production.

Advantages and disadvantages of sunlight

If modern humans continue to live indoors and stay out of the sun to avoid premature aging and skin cancer, we must find a way to replace the essential energy of the sun if we are to continue to thrive. Recently, interest has been given to vitamin D supplementation as a possible solution because it is the only photosynthetic product that can be delivered in pill form. But vitamin D is not actually a vitamin at all. It is a pro-steroid hormone. Very few foods contain measurable amounts of vitamin D. The human body is designed to make its own vitamin D through the skin when exposed to sunlight, rather than absorbing this important hormone through the digestive system. 

It is important to avoid excessive doses of oral vitamin D. If vitamin D intake is too high, it can cause elevated blood calcium levels, vitamin D toxicity, and potentially dangerous consequences. Unlike oral supplements, you cannot overdose on the vitamin D3 that your skin produces. If you have enough vitamin D, your body will produce less. Using light to make vitamin D allows your body to self-regulate vitamin D production and make what it needs to stay healthy, without the risk of overdose or toxicity. 

There are many benefits of vitamin D from the sun that we don’t get in supplemental sources of vitamin D, research shows that while high levels of vitamin D from the sun are helpful in preventing disease, vitamin D supplementation It does not offer the same benefit. [The discrepancy in the benefit received from sunlight-induced vitamin D versus supplemental vitamin D can be explained by one simple fact: the association between high blood levels of vitamin D and disease prevention in epidemiological research actually measures sun exposure and no supplemental vitamin D. Population studies have repeatedly demonstrated that exposure to sunlight is a greater contributor to vitamin D concentration than oral administration. Higher serum concentrations are indicative of increased skin contact with the sun’s life spectrum.

 Assuming that the body’s vitamin D level from birth control pills represents the same health benefits as light-derived vitamin D leads to incorrect research conclusions. It does not take into account the benefits of the sun on the human body outside of vitamin D production. It is important to understand that there are other vital elements that contribute to the health of our system in addition to Vitamin D. While the contributions of each of these photovoltaic products to our systemic health continue to be explored by researchers, one thing is clear: Humans need sun exposure to stay healthy and we don’t get enough in our modern society.

 While the sun may be the best source of vitamin D, excessive sun exposure can cause skin damage. It is difficult to determine exactly how much sun is required to gain an advantage with minimal risk on an individual basis given the many influence factors.