It’s late spring…
… and we survived a long winter time now to get out in the sun to improve our health, right? Well, it all depends on your point of view. If your exposure to the ‘sun gives you skin cancer’ then, no. However, if you’re in it for natural vitamin D, then yes. Who to believe?
Good health begs the question – to keep our personal immunity level up, should we get into the sun, or stay the hell out of it?
We love our dermatologists, they want nothing but the best for us and they view sunlight as evil, it is the cause of skin cancer. If they have their way, we would all be living in dark caves with zero chance of skin cancer.
However, there’s mounting evidence that sunshine is good for us and may prevent cancers, even skin cancer. What?
Swedish Study of Sunbathers
A Swedish study published in 2016 actually found that women sunbathers lived longer than those who avoided the sun. It found that among nearly 30,000 women in Sweden, who were each monitored for about 20 years, those who spent more time in the sun actually lived longer and had less heart disease and had fewer non-cancer deaths than those who reported less sun exposure.
Although the sunbathers did have an increased risk of skin cancer, their skin cancers had “better prognosis” than those non-sunbathers who were in the control group and also contracted skin cancer, seems counter intuitive.
Further, these sunbathing women had less morbidity and mortality by “all causes: than the control group. They also lived longer by up to 2 years. What’s going on here? What’s with the sun?
The result of the tests found correlation but not necessarily causation. The reason why more sun exposure might prolong life or prevent heart disease deaths could not be unequivocally concluded from this study.
The World Health Organization has compiled a number of other trend line studies. Some studies have shown a higher incident of mortality in winter than in summer. Also lower blood pressure in summer than in winter.
The assumption is that it’s because the sun’s ultraviolet light triggers chemical reactions in the skin that lead to the production of vitamin D. People up north just get less sun during winter. It’s therefore highly probably that vitamin D is responsible for the health benefits.
Just what is vitamin D anyway?
Scientists know that vitamin D is highly necessary for proper gene expression. It’s a steroid hormone the affects the expression of a 900 – 1,000 different genes. You can’t stay healthy without it.
Therefore Vitamin D is considered “conditionally essential” — if you’re not exposed to the sun, you must get your vitamin D from other means.
Some researchers claim that vitamin D is technically not even a vitamin, its primary metabolic product, calcitriol, is a hormone
There are actually 5 forms of vitamin D: vitamins D1 – D5
Two major forms are:
D2: “ergocalciferol”
D3: “cholecalciferol”
Vitamin D2 is not produced by human body, it’s vitamin D3 that is manufactured by our skin and which gives the major health benefits.
Human skin converts sunshine to active vitamin D through a multistep process into a form your body can best use. The first transformation occurs in the liver. Here, your body converts vitamin D3 to a chemical known as 25-hydroxy vitamin D, also called calcidiol.
Then the kidneys conduct a 2nd step converting 25-hydroxy vitamin D into 1,25 dihydroxyvitamin D (1,25 (OH)2D), known as calcitriol. This plays a crucial role in the maintenance of blood calcium and phosphorus levels and in normal skeletal mineralization.
Benefits of Vitamin D
It All Began with Rickets
We don’t hear of that insidious disease, rickets, anymore. But back in the 17th century it affected a lot of children. But then an inverse relationship between sunshine and rickets was discovered. The more sun exposure, the less chance of children contracting rickets. Doctors deduced that it was the natural vitamin D that prevented rickets.
That is why milk became fortified with vitamin D. According to the U.S. National Institutes of Health almost all of the U.S. milk supply is fortified with 400 IU of vitamin D per quart. Rickets today is under control in most countries with some form of vitamin D solution.
Protects from Osteoporosis
Most women are fully aware of the need to supplement with calcium to promote strong bone growth, but that’s only half the equation, they also need vitamin D to aid in the absorption of the calcium and thus stave off osteoporosis. We can can’t absorb calcium or phosphorous without vitamin D.
Reduced Cancer
In June of 2018 the National Institute of Health conducted a 5 year study and found that participants who were vitamin D deficient had a 31% higher chance of developing colorectal cancer than those with sufficient levels of vitamin D.
Reduced Heart Disease
Those with the lowest vitamin D levels have more than double the risk of dying from heart disease and other causes over an eight-year period compared to those with the highest vitamin D levels.
Reduced Depression
Fewer symptoms of depression may be reported after spending time in the sun. In particular, it regulates Tryptophan hydroxylase which is an enzyme involved in the synthesis of the neurotransmitter serotonin, the “feel good” hormone which may explain why many people are happy on sunny days. Sunlight can boost mood and promote feelings of calm. Even without depression, spending time in the sunshine will likely boost mood.
Strengthens the Immune System
But vitamin D does much more than protect bone and muscle development. It helps brain nerve cells carry messages, and helps the immune system fight off invading bacteria and viruses.
Studies have shown that vitamin D deficiency impairs the immune system, and some older studies found that vitamin D supplements may reduce the risk of respiratory virus infections and immune system overreaction.
Anti-aging Affects
Telomeres are the end caps of chromosomes. Every time cells divide telomeres shorten slightly, in our later years that’s a lot of cell divisions. Telomere length is a biomarker for aging. The anti-inflammatory properties of Vitamin D mitigate the shortening of telomeres. The longer the telomere, the longer the life expectancy.
Unfortunately, aging affects the natural vitamin D production in skin. 75% less vitamin D is produced by the skin of a 70-year-old vs a 20-year-old. Something to keep in mind if you want to keep those telomeres at a healthy length.
Low vitamin D can lead to higher incidences of:
- Infections and cancers
- Rheumatoid arthritis
- Diabetes
- Multiple sclerosis
- Hypertension
- Heart disease
Most Americans are low in vitamin D
In northern latitudes, Americans are not exposed to enough sunshine to manufacture enough vitamin D for half the year. We’re stuck indoors and wear heavy clothes when we do go outside.
For those of you above latitude 32° north or higher take heed (around Atlanta, Georgia and northward), you will not get enough sun, and therefore vitamin D, in winter.
Also, during those summer sunshine months there is an overuse of sunscreen. Sunscreens are very effective in blocking UVB radiation and therefore preventing natural vitamin D production.
Take the Weight Off
Being overweight will affect your vitamin D availability. Vitamin D is fat soluble and carrying too much body fat will affect its bioavailability because it’s being stored in the fat and not released into the bloodstream.
Dark Skin Shields UVB
Darker skinned people will naturally block sunlight and UVB. So, if they want to absorb more vitamin D naturally from sunshine, they need to spend more time in the sun than white counterparts.
Caucasians that have deep tans are actually putting up a barrier to absorbing natural vitamin D. So, it’s a double whammy, not only are they aging their skin, but they’re putting a barrier up between them and the benefits of sunshine.
Know your Numbers
The only real way to know if you have healthy levels of vitamin D in your system is to get tested. If you have an annual physical with blood tests, be sure to discuss having your vitamin D levels tested by your doctor.
The medical community uses a scale of nanograms (ng) per milliliter (ml). Vitamin D tests generally assess the total volume of 25-Hydroxyvitamin D (25OHD), which is the form of Vitamin D circulating in blood.
Optimum levels are between 30-80 ng/ml.
<10.0 ng/ml.: Deficient
10.0 – 30.0 ng/ml.: Insufficient
30.1 – 100 ng/ml.: Sufficient
>100 ng/ml.: Toxic
Optimal Sunbathing
The UV index is linear scale running from 0 to 11+. You really need a UV index reading of at least 3 for your skin to make vitamin D.
So, the challenge is to get that goldilocks level of sun exposure for good health but not burn your skin or damage your eyes.
Never get sunburned, that’s what can lead to melanoma.
Allow about 20 minutes or so of unprotected sun exposure to your arms, legs, abdomen and back. After that, follow up with good sun protection, like a 30-SPF or higher sunblock. The mission is to generate natural vitamin D and not to damage the skin.
The irony of tanning. If you have a dark tan, it actually reduces your skin’s ability to product vitamin D. The lighter you are, the more efficient at producing vitamin D.
If your shadow is longer than your body height, you can’t make any vitamin D, high noon will be too intense, aim for the window of 10:00am – 11:00am or 2:00pm to 3:00pm.
UVB does not penetrate through glass or plastic, you have to be outside, unobstructed.
Foods high in vitamin D
During winter, when you’re no longer exposed to beneficial sunshine, you’ll need other means to get necessary vitamin D. One way is through diet.
Fatty cold water fish contain vitamin D. Eat the small fish and not the mercury ridden large ones like tuna. Wild Alaska salmon is ideal. Farm raised salmon are lower in vitamin D. Other fish like mackerel and sardines are also good.
Other food sources of vitamin D are:
- Beef live
- Whole eggs
- UV exposed mushrooms. (Yes, mushrooms exposed to the sun also manufacture and store vitamin D).
Need to supplement in winter during the winter
Vitamin D is rare in most foods and many people simply cannot get enough of it from these food sources alone. So, if you cannot expose your skin to sunshine, you must supplement.
The NIH guidelines for vitamin D supplementation is 600 IU for adults and 800 IU for seniors over 70 years of age.
However, most medical experts feel these levels are too low for maximum benefit. They suggest 4,000 IU per day.
Can you take too much vitamin D?
Yes, supplementing too much vitamin D is possible but not common. Toxic doses of vitamin D can result in exceedingly high serum levels of calcium, known as hypercalcemia and have been reported at doses higher than 50,000 IU.
Data compiled from several different vitamin D supplementation studies reveal that vitamin D toxicity is obtained at doses much higher than 10,000 IU. So, 4,000 IU is safe and offers major benefits.
How Does Your Body Make It?
Vitamin D3 is made by cholesterol in the skin when 7-dehydrocholesterol reacts with ultraviolet-B radiation (UVB) at wavelengths between 290-315 nm. Supplements are typically made through UVB irradiation of 7-dehydrocholesterol in lanolin of sheep.
Most of you are familiar that sunlight is composed of wavelength bands, we can only see the middle light bands, but the lower frequency comprises ultraviolet and the higher frequency comprises infrared.
But the UV frequency also has three parts:
-
Sunlight is comprised of a spectrum, it is the UVB that makes our vitamin D. UVA
- UVB
- UVC
The UVC frequencies are almost completely absorbed by the earth’s atmosphere and don’t reach the earth and are therefore inconsequential.
UVB is the radiation that both generates beneficial vitamin D in the skin and if excessive can cause skin damage and skin cancer. However, in mornings and late afternoon, due to the angle of the sun, the radiation passes through more ozone. It’s the ozone layer which reduces the intensity of the UVB radiation to where it causes less damage.
UVA, on the other hand, penetrates the ozone layer all day long and reaches our skin. But it’s not the radiation that produces vitamin D.
There are theories that it’s not necessarily the vitamin D converted from UVB that gives us all of our anti-aging and health benefits but the benefits of the UVA radiation. UVA causes the skin to produce Nitric Oxide which some medical experts feel has positive healthy benefits.
In Summary
Vitamin D is a key component of overall good health.
Sunlight is not a villain. We need its exposure on our skin on a regular basis. In fact, the very reason why some humans have white skin at all is because early in our existence some homo sapiens left Africa and migrated to norther Europe. In time they lost pigments in the skin so as to generate beneficial vitamin D with so little sunlight. It’s all natural and highly necessary to our optimal health.
Today, in modern times, those of us living in the north during winter, must therefore get our necessary vitamin D through diet and supplementation.