How to get vitamin D from sunlight - NHS
Vitamin D's primary function is to help the body absorb calcium, though it may also protect against prostate Second, the sunlight connection. (8) completed a number of epidemiologic studies and noted that there was a strong negative correlation between latitude, sun exposure, and poor vitamin D. Your Vitamin D levels depend on your exposure to sunlight and UV rays. However there are The difference between UVA and UVB. While there are many.
Both bone diseases are now rare in the United States, but another is on the rise "" osteoporosis, the "thin bone" disease that leads to fractures and spinal deformities. Low levels of vitamin D lead to low bone calcium stores, increasing the risk of fractures. If vitamin D did nothing more than protect bones, it would still be essential.
But researchers have begun to accumulate evidence that it may do much more. In fact, many of the body's tissues contain vitamin D receptors, proteins that bind to vitamin D. In the intestines, the receptors capture vitamin D, enabling efficient calcium absorption. But similar receptors are also present in many other organs, from the prostate to the heart, blood vessels, muscles, and endocrine glands.
And work in progress suggests that good things happen when vitamin D binds to these receptors. The main requirement is to have enough vitamin D "" but many Americans don't. Vitamin D deficiencies Vitamin D deficiencies were rare when most men rolled up their sleeves to work in sunny fields. But as work shifted from farms to offices, that changed.
Deficiencies are also common in patients with intestinal disorders that limit absorption of fat and those with kidney or liver diseases that reduce the conversion of vitamin D to its active form, calcitriol 1,25 OH 2D. In addition, certain medications reduce the availability or activity of vitamin D.
And even in healthy people, advancing age is linked to an increased risk of vitamin D deficiency. A number of factors can play a role. Limited exposure to sunlight heads the list. Except during the short summer months, people who live at latitudes above 37 degrees north or below 37 degrees south of the equator don't get enough UVB energy from the sun to make all the vitamin D they need. The same is true for people who spend most of their time indoors and for those of us who avoid sunshine and use sunscreens to protect our skin from the harmful effects of ultraviolet radiation see box below.
It's an example of an unforeseen consequence of wise behavior, but you can enjoy sun protection and strong bones, too, by taking vitamin supplements. Sunscreens Like politicians, doctors often have to compromise; when it comes to sunshine, most pols promise blue skies, while most docs turn out to be the shady guys "" or, at least, sunscreen advocates.
UVB provides the energy your skin needs to make vitamin D, but that energy can burn the skin and increase the cell damage that leads to cancer. UVA also contributes to skin damage and premature aging. To protect yourself, avoid the summer sunshine, especially between 10 a. Whenever possible, wear a large-brimmed hat and a tightly woven, dark-colored long-sleeve shirt and long pants when you go out in the sun. But summer garb is usually lightweight and exposes a lot of skin.
That's where a sunscreen comes in. Look for a product with an SPF of at least 15; fair-skinned people would be wise to shoot for 30 or higher. But since SPFs apply only to UVB, look for a "broad spectrum" sunscreen that also protects against UVA; most contain titanium dioxide, zinc oxide, or avobenzone also known as Parsol Above all, apply your sunscreen early, often, and liberally.
These many factors explain why vitamin D deficiencies are shockingly common in the United States.How to Safely Get Vitamin D From Sunlight
And low levels of vitamin D are common even in apparently healthy young adults; in one study, more than a third of people between the ages of 18 and 29 were deficient.
Numbers can never tell the whole story, but in this case, "D-ficiencies" add up to a wide range of health concerns. Osteoporosis and fractures It's a paradox: Skeletal health is the best-known contribution of vitamin D, but it has also become the most controversial. Although doctors agree that vitamin D deficiency increases the risk of osteoporosis and fractures, they disagree about the benefits and optimal dosage of supplements.
Without enough vitamin D, the intestines cannot efficiently absorb calcium. But because blood calcium is critical for neuromuscular and cardiac function, the body does not allow levels to fall. Instead, it pours out parathyroid hormone, which mobilizes calcium from bone. Blood calcium levels remain normal, so your heart and nerves keep working nicely.
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But your bones bear the brunt: As bone calcium density falls, bones become weak and fracture-prone. Most studies show that a lack of vitamin D increases the risk of osteoporosis and the likelihood of hip and other nonspinal fractures. But there is considerable disagreement about how much supplements reduce the risk of fractures.
Some studies include only women, others both men and women; some include only frail, elderly, or institutionalized subjects, others physically active people; some use vitamin D alone, others a combination of D and varying doses of calcium; and some administer international units IU of vitamin D a day, others up to IU a day. In contrast, supplements of IU a day, the conventional dose, had no benefit. Most authorities agree that high doses of vitamin D supplements appear to protect against fractures and low doses do not.
But two trials that found no benefit from IU a day were completed after the meta-analysis, ensuring that the proper dose will remain a bone of contention. Prostate cancer Some men mistakenly dismiss osteoporosis as a women's worry, but none fail to recognize the importance of prostate cancer. Vitamin D has an important role in regulating cell growth.
Laboratory experiments suggest that it helps prevent the unrestrained cell multiplication that characterizes cancer by reducing cell division, restricting tumor blood supply angiogenesisincreasing the death of cancer cells apoptosisand limiting the spread of cancer cells metastasis.
Like many human tissues, the prostate has an abundant supply of vitamin D receptors.
Does the Sun Give People Vitamin D? | Healthy Eating | SF Gate
And, like some other tissues, it also contains enzymes that convert biologically inactive 25 OH D into the active form of the vitamin, 1,25 OH 2D. These enzymes are much more active in normal prostate cells than in prostate cancer cells.
Do the results from these experiments translate into clinically important effects? Several lines of evidence are relevant. First, the calcium connection.
InHarvard's Health Professionals Follow-up Study of 47, men reported that a high consumption of calcium, either from food or supplements, was associated with an increased risk of advanced prostate cancer; the risk was greatest in men taking more than 2, mg of calcium a day.
Since then, other studies have confirmed a link between very high levels of dietary calcium and increased risk, but they have exonerated modest calcium consumption. The Harvard scientists speculate that the problem is not calcium itself but a relative lack of active vitamin D.
That's because high levels of calcium can reduce the body's production of the active form of the vitamin. Second, the sunlight connection. Of course, sunlight is just one of the many differences between these groups of men, and various genetic, dietary, lifestyle, and health care disparities could account for the prostate cancer gap.
Indeed, early studies failed to demonstrate a clear association between blood levels of 25 OH D and prostate cancer. And certain genetic variations in the vitamin D receptor appeared to enhance the protective effect of the vitamin.
Can vitamin D reduce your risk of prostate cancer? It's too early to say "" but it's a possibility that requires additional study.
Other malignancies The risk of colon cancer, breast cancer, and other malignancies appears to rise in populations at latitudes far from the equator. Sun exposure and vitamin D levels may be part of the explanation. As in the case of prostate cancer, the details vary from study to study. After taking her course of antibiotics to treat her existing infection, she began going for walks in the park with me every day that the weather permitted.
Her mood improved after the first day of this, and she saw what she had been missing all along.
What is the Connection Between Vitamin D and Sunlight?
When the ground is covered in snow, it is just too cold to be going out without most of their bodies covered. So, they have to settle for vitamin D from food sources during these icy months. They eat fortified milk with their fortified cereal, and they also drink the milk at other times of the day. He told me that they make it a point to eat tuna once a week, since it is a good source of vitamin D.
They also eat eggs several times a week. As far as he knows, none of them have suffered symptoms of a vitamin D deficiency.
The food source trick must be working. In the summer, they absorb plenty of sun. They appreciate the warmth so much while they can, because they know it won't be around for very long. I'll be taking my baby daughter out for a walk this afternoon to see if it works for kids, too!
Vitamin D: The “sunshine” vitamin
I've also heard that vitamin D is stored in the body's fat cells. So if you normally get a lot of sun, you might not need to take a supplement on rainy days.
It's not like vitamin C, which apparently you have to take every single day as the body can't store it. But that also means you have to be careful not to get too much vitamin D.
Vitamin D and your health: Breaking old rules, raising new hopes
Most people don't get nearly enough, but if you eat a lo of fortified foods, take both a calcium supplement and a multivitamin, and spend a lot of time outside, you could get too much and get really sick. ElizaBennett Post 1 Getting more sun is the most natural way to treat a lack of vitamin D, and it has other benefits as well - studies show that getting more sun during the day helps people sleep better at night, for instance.
If the weather is warm enough to leave your arms and legs uncovered, let those soak up the vitamin D while you protect more sensitive areas.