The more we move away from a way of life adapted to the environmental conditions we live, involving alternation of light and dark, heat and cold, and seasonal changes, the more essential supplementation becomes. However, supplementation will never be as effective as a way of life integrated into natural cycles.
"After finishing my medical studies," says Alexander Wunsch , a German physician who specializes in holistic medicine and phototherapy, "I was very disappointed to discover that everything in therapy revolves around pharmaceuticals. But I was looking for a physiological way to restore the human body as naturally as possible. So first, I tried to look at nature and understand what was going on there, and then I wanted to see if it made sense to replicate what I found in nature or if another solution was required. By the way, the better you sync with the environment, the more energy your body will be able to save. As a result, you will be able to function at an optimal level of energy, which is the essence of the whole issue of the circadian cycle (day-night) and chronobiology". (Chronobiology is a field of biology that studies the biological rhythms determined by the solar cycle.)
But, he adds, you must be prepared to respond to this environmental action, "which is essential for any form of life. As a result, if a plant, bacterium, or simple cell is not ready to receive the light that will appear in an hour, its metabolism will lag. The inability to adapt to the temporal rhythms of the environment determines a change in reaction. And being late is never a good thing."
The internal clock
"For example, if you're late for the train station and you're out of breath to catch it," Wunsch continues, "you'll need a lot more energy to catch it than if you left early." When you are late, you use a lot of energy because instead of sitting comfortably in your seat, waiting for the train to leave, you rush to get on at the last minute. Returning to the plant, if she knows from her internal clock that the sun will rise in an hour, her metabolism will change because continuously alternating energy flow forces plants and other living beings to automatically react to the change in environmental characteristics.
For example, when it comes to temperature, we have much higher temperatures during the day when the sun shines, whereas there is a lack of heat at night. As a result, the body will cool down during the day and warm up at night; we are active during the day and rest at night; we consume food during the day and digest it at night. During the day, we are under the influence of stress, and at night, we inhibit stress hormones from allowing the immune cells to function. Everything in life is like a pendulum - an excellent representation of any parameter in our metabolism: food digestion, movement-rest, and so on. And you can see this in all hormones, in all aspects of life - everything is subject to this basic principle of alternating light with darkness, activity with rest, and so on. However, if you avoid this rhythm and fall out of sync, your body will lose a lot of energy.
The sun is our primary source of energy, which "causes a flow and distribution of energy since the Earth revolves around its axis, this rotation creating the day-night cycle," Wunsch explains. "We should all be aware that if the sun did not shine, nothing on this planet would be alive in 2-3 days." We eat transformed light when we eat, and this is scientifically proven. "I believe that, while we cannot estimate the impact of light on our biological system as a whole, it begins at the level of a simple cell and progresses to the level of consciousness, our mental functions."
According to Dr. Wunsch, the human body is adapted to the light conditions of the environment: stronger natural light, unfiltered during the day, dim light in the evening, and then darkness. However, the current pace of life has resulted in a reversal of these natural conditions, resulting in low natural light during the day and excessive artificial light in the evening and at night. For example, people used to work outside in direct sunlight; nowadays, most of us spend our time in the office, in the car, and at home, with minimal contact with the sun's rays.
For example, in a study  on ultraviolet radiation and vitamin D levels, researcher Ola Engelsen of the Norwegian Institute for Air Research discovered that there was a significant tendency to reduce time spent outdoors, "either due to the conditions of or leisure preferences." For example, in the United States, children spend only about half an hour outside on weekends and only a few minutes during the rest of the day.
The sun is the great healer.
The healing power of sunlight and its use in medical treatment dates back to antiquity, with heliotherapy being one of the oldest healing methods used for thousands of years to fight disease and boost immunity. The ancient people also used the sun's rays to sterilize and dry food and photochemically activate pharmaceutical preparations.
The great historian Herodotus described the use of solariums - some treatment areas based on sunlight - in 450 BC, saying that "sun exposure is highly recommended for those who need to regain their health." Likewise, Hippocrates (460–370 BC), known as the "Father of Medicine," emphasized the importance of light and heat emitted by light in strengthening the bone structure and treating various ailments such as rickets and obesity, and metabolic disorders. The link between light and health was evident to the Greeks: Asclepius, the god of medicine and healing, was the son of Apollo, the god of the sun. And the Romans, the Greeks' cultural descendants, adopted this medical approach. As a result, their civil code included provisions relating to the "right to light," which guaranteed citizens access to sunlight in their homes, which frequently had a solarium. Soranus of Ephesus, a Greek who practiced in Rome and was one of the most outstanding physicians of the second century AD, advocated exposing newborns to jaundice in the sun, thus supporting modern treatments for neonatal jaundice using blue light . According to the Greek physician Antyllus in the second century AD, the ancients also sunbathed to strengthen their "weak and flabby muscles" and train gladiators.
Heliotherapy was widely used in modern times, particularly in the first half of the twentieth century, in Europe and North America, particularly in treating cutaneous tuberculosis. Niels Finsen received the Nobel Prize in Medicine in 1903 for this treatment. Much of his research was conducted before discovering Vitamin D and its synthesis in the skin by ultraviolet radiation, the primary factor in the reported recovery from the disease a century ago . Furthermore, during the 1918-1919 Spanish flu pandemic (H1N1), heliotherapy was used in open-air hospitals (Boston, Massachusetts), where the combination of fresh air, sunlight, and high standards of hygiene significantly reduced both patient deaths and infections among medical staff . However, the "drug era" began with the discovery of antibiotics, and heliotherapy fell out of favor, becoming almost forgotten today. Avoiding prolonged hospitalization is a significant benefit of antibiotics, but this is only a matter of efficacy, not therapeutic efficacy.
Skin cancer and the sun
Current medicine not only ignores but even actively avoids Heliotherapy, as concluded a 2015 study on the role of sunlight and Vitamin D in public health, conducted by Alexander Wunsch et al. : "The World Health Organization's International Agency for Research on Cancer (WHO) recommends avoiding outdoor activities at noon and wearing full-body clothing, as well as using sunscreen on frequently exposed skin areas daily." Furthermore, the American Cancer Society recommends covering our skin with clothing or sunscreen and avoiding exposure between 10 a.m. and 16 a.m.
Although all of these recommendations aim to lower the risk of skin cancer and acknowledge the importance of Vitamin D for health, they insist on avoiding the sun between 10.00 and 15.00, when Vitamin D can be synthesized in the skin, and suggest that all Vitamin D needs can be met through diet and supplements.
According to the researchers mentioned above, these recommendations "ignore the fact that we have a long culture of harnessing the sun and ultraviolet radiation for therapeutic purposes." Furthermore, it ignores the fact that we have evolved physiologically to protect our skin from the sun, as well as the fact that increased exposure to the sun, adapted to latitude, has been linked to the prevention of various types of cancer, type 1 diabetes, multiple sclerosis, and other diseases," including autoimmune diseases , hypertension , and influenza .
A study  conducted on the population of Seattle, where the rate of melanoma diseases is very high, shows that the cause of the disease is a lack of sun exposure, favored by the climate, and excessive use of sunscreens with chemical filters. Instead, Dr. Wunsch advises using mineral or natural oil-based protective creams, as has been done since antiquity. "Would you eat sunscreen?" Then why put it on your skin? "The skin absorbs everything you put on it as if it were swallowed," says Clare Badrick, an osteopathy and naturopathy specialist.
As a result, optimal health requires exposure to the entire solar spectrum. People are physiologically adapted to produce Vitamin D in response to sun exposure, particularly ultraviolet B radiation, while other wavelengths of the solar spectrum provide additional benefits. We obtain Vitamin D in part through diet and, more recently, supplements, but we must not overlook our body's natural ability to produce it.
(to be continued)
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