Sun exposure is by far the best way to boost vitamin D levels, particularly because very few foods contain significant amounts. Midday, especially during summer, is the best time to get sunlight. At noon, the sun is at its highest point, and its UVB rays are most intense. That means you need less time in the sun to make sufficient vitamin D ( 5 ).
How exactly does the sun provide us with vitamin D?
Vitals
- Vitamin D is a prohormone that supports several key body processes.
- Our bodies can produce vitamin D when our skin is exposed to the sun.
- Getting vitamin D through sunbathing has pluses and minuses.
- If you’re concerned about your level of vitamin D, a healthcare provider can check it with a simple blood test.
How much vitamin D does the sun really produce?
Vitamin D3 is made in large quantities when you are in the sun during peak UV times. In fact it is estimated that 30 minutes in the sun (ideally in a bathing suit), midday in summer can make up to 20,000 IU of Vitamin D. If you get too much sun, the skin is able to convert the excess Vitamin D to other inactive molecules.
What is the connection between the Sun and vitamin D?
Vitamin D is made in the body when the sun’s ultraviolet B (UVB) rays hit the skin, setting off a reaction that triggers the synthesis of the sunshine vitamin. Vital for calcium absorption, nerve conduction, immune function and the reduction of inflammation, vitamin D is one of the body’s most essential nutrients.
Does the Sun give people vitamin D?
While the sun does not provide vitamin D directly, standing in the sun for a couple of minutes every day helps your body meet some of its needs for the vitamin. Sunlight triggers the first of three...
How long do you have to be in sun for vitamin D?
Regular sun exposure is the most natural way to get enough vitamin D. To maintain healthy blood levels, aim to get 10–30 minutes of midday sunlight, several times per week. People with darker skin may need a little more than this.
Can you still get vitamin D from the sun?
The sun is our best natural source of vitamin D. Spending even a short time in the sun can provide the body with all of the vitamin D it needs for the day. According to the Vitamin D Council, this could be: 15 minutes for a person with light skin.
Do you have to stand directly in the sun to get vitamin D?
It's the UVB rays that trigger the synthesis of vitamin D. Many people can derive the vitamin D that their bodies need through direct exposure to sunlight during the summer months. As little as 10 minutes a day of sun exposure is typically adequate.
Can you get vitamin D from the sun after 4pm?
Vitamin D, also known as the “sunshine vitamin,” is synthesized in the skin following direct exposure to UVB rays. However, the UV index must be over 3 to make vitamin D, which usually occurs around midday between 10am and 2pm.
How can I raise my vitamin D levels quickly?
You can raise your vitamin D levels quickly in three main ways: Getting outside and exposing your skin to sunlight. Taking a vitamin D supplement....Eat foods rich in vitamin DCod liver oil*Trout*Salmon*Mushrooms*Fortified dairy and non-dairy milks.Fortified cereals.Sardines.Eggs.More items...•
Is 5 minutes of sun enough?
This answer is different for everyone. It depends on your skin tone, age, health history, diet, and where you live. In general, scientists think 5 to 15 minutes -- up to 30 if you're dark-skinned -- is about right to get the most out of it without causing any health problems.
Which part of the body absorbs most vitamin D?
The vitamin D that is consumed in food or as a supplement is absorbed in the part of the small intestine immediately downstream from the stomach. Stomach juices, pancreatic secretions, bile from the liver, the integrity of the wall of the intestine — they all have some influence on how much of the vitamin is absorbed.
Can you get vitamin D 5pm?
The best time to soak yourself in the sun to get the maximum vitamin D is between 10 am to 3 pm. At this time, the UVB rays are intense and it is also said that the body is more efficient in making vitamin D at this time.
Why is vitamin D important for health?
The high prevalence of vitamin D insufficiency is a particularly important public health issue because hypovitaminosis D is an independent risk factor for total mortality in the general population. [5] Emerging research supports the possible role of vitamin D against cancer, heart disease, fractures and falls, autoimmune diseases, influenza, type-2 diabetes, and depression. Many health care providers have increased their recommendations for vitamin D supplementation to at least 1000 IU.[6] A meta-analysis published in 2007 showed that vitamin D supplementation was associated with significantly reduced mortality.[7] In this review, we will focus on the biology of vitamin D and summarize the mechanisms that are presumed to underlie the relationship between vitamin D and its clinical implications.
How does vitamin D work?
Vitamin D undergoes two hydroxylations in the body for activation. Calcitriol (1,25-dihydroxyvitamin D3), the active form of vitamin D, has a half-life of about 15 h, while calcidiol (25-hydroxyvitamin D3) has a half-life of about 15 days.[63] Vitamin D binds to receptors located throughout the body. 25(OH)D is transformed by renal or extrarenal 1α-hydroxylase into 1,25-dihydroxyvitamin D (1,25[OH]2D), which circulates at much lower serum concentrations than 25(OH)D, but has a much higher affinity to the VDR.[64] Studies have, however, shown that many other cell types, including those of the vascular wall, express 1α-hydroxylase with subsequent intracellular conversion of 25(OH)D to 1,25(OH)2D, which exerts its effects at the level of the individual cell or tissue before being catabolized to biologically inactive calcitroic acid.[1,65,66] Factors such as fibroblast growth factor 23 and Klotho, which suppress 1α-hydroxylase expression, have also been shown to regulate the renal conversion of 25(OH)D to 1,25(OH)2D.[67] Importantly, extrarenal 1α-hydroxylase expression also underlies various regulatory mechanisms. In this context, extrarenal 1,25(OH)2D productions in macrophages are stimulated by Toll-like receptor as part of the innate immune response against intracellular bacteria.[68] Another example of extrarenal regulation of 1α-hydroxylase is that the increased production of 1,25(OH)2D by keratinocytes in wounds[69] therefore provides a good estimate of vitamin D status, but regulation of 1α-hydroxylase activity should also be considered. Vitamin D crosses the blood–brain barrier and the receptors for vitamin D are found across the brain, but its precise role is still not known.
What is the recommended vitamin D level for VDD?
VDD has been historically defined and recently recommended by the Institute of Medicine (IOM) as a 25(OH)D of less than 0.8 IU. Vitamin D insufficiency has been defined as a 25(OH)D of 21–29 ng/mL.[1,18–23] Children and young- and middle-aged adults are at equally high risk for VDD and insufficiency worldwide. VDD is common in Australia, the Middle East, India, Africa, and South America.[1,24,25] Pregnant and lactating women who take a prenatal vitamin and a calcium supplement with vitamin D remain at high risk for VDD.[26–28]
What is the main source of vitamin D?
The major source of vitamin D for children and adults is exposure to natural sunlight.[ 1,29–32] Thus, the major cause of VDD is inadequate exposure to sunlight.[29,33–35] Wearing a sunscreen with a sun protection factor of 30 reduces vitamin D synthesis in the skin by more than 95%.[36] .
What are the causes of hypovitaminosis D?
This pandemic of hypovitaminosis D can mainly be attributed to lifestyle (for example, reduced outdoor activities) and environmental (for example, air pollution) factors that reduce exposure to sunlight, which is required for ultraviolet-B (UVB)-induced vitamin D production in the skin.
How much vitamin D is in a multivitamin?
Traditional multivitamins contain about 400 IU of vitamin D, but many multivitamins now contain 800 to 1000 IU. A variety of options are available for individual vitamin D supplements, including capsules, chewable tablets, liquids, and drops. Cod liver oil is a good source of vitamin D, but in large doses there is a risk of vitamin A toxicity.[70]
What is the role of Vitamin D receptor in the body?
Vitamin D receptor (VDR) is present in most tissues and cells in the body.[6,14] 1,25(OH)2D has a wide range of biological actions, such as inhibition of cellular proliferation and inducing terminal differentiation, inhibiting angiogenesis, stimulating insulin production, inhibiting renin production, and stimulating macrophage cathelicidin production. [6,14–16] The local production of 1,25(OH)2D may be responsible for regulating up to 200 genes[17] that may facilitate many of the pleiotropic health benefits that have been reported for vitamin D.[3,8,9,14]
How to get enough vitamin D?
Some nutrition experts believe it is possible to get enough vitamin D by eating the right foods – combined with supplements if needed. Fish such as wild-caught salmon, mackerel, tuna and sardines; beef liver, eggs, cod liver oil and mushrooms are good vitamin D sources.
How to reduce vitamin D levels?
You can also take other preventive measures – wearing a hat that shades your face, applying sunscreen and avoiding or minimizing your time in the sun between 10 a.m. and 4 p.m., when UV rays are generally the strongest.
Why isn't my skin producing enough vitamin D?
Even if you jog in the early morning on a bright, sunny day, you may not produce enough vitamin D because there are not sufficient UV rays early in the morning, Lucas said.
What is the best vitamin for bones?
Aside from that, the role of vitamin D – commonly known as the sunshine vitamin – in keeping bones strong is already well-established. Ideally, people should get enough vitamin D from their food. Foods that are high in vitamin D include: Egg yolk. Fortified milk and yogurt. Liver.
Why is it impossible to get vitamin D in the winter?
In the winter, it's virtually impossible to produce vitamin D from the sun if you live 37 degrees above the equator (or north of Atlanta), because the sun never gets high enough in the sky for its ultraviolet B rays to penetrate the atmosphere , according to Harvard Womens' Health Watch.
How often do you get a sunburn?
Suffering a sunburn even once every two years can triple your risk of contracting melanoma, according to Cancer Research UK. The American Cancer Society does not support sun exposure for increasing vitamin D.
What is the benefit of sunlight?
What's more, sunlight has other hidden benefits – like protecting against depression, insomnia and an overactive immune system.
What is vitamin D3?
Vitamin D is the sunshine vitamin that has been produced on this earth for more than 500 million years. During exposure to sunlight 7-dehydrocholesterol in the skin absorbs UV B radiation and is converted to previtamin D3 which in turn isomerizes into vitamin D3. Previtamin D3 and vitamin D3 also absorb UV B radiation and are converted into a variety of photoproducts some of which have unique biologic properties. Sun induced vitamin D synthesis is greatly influenced by season, time of day, latitude, altitude, air pollution, skin pigmentation, sunscreen use, passing through glass and plastic, and aging. Vitamin D is metabolized sequentially in the liver and kidneys into 25-hydroxyvitamin D which is a major circulating form and 1,25-dihydroxyvitamin D which is the biologically active form respectively. 1,25-dihydroxyvitamin D plays an important role in regulating calcium and phosphate metabolism for maintenance of metabolic functions and for skeletal health. Most cells and organs in the body have a vitamin D receptor and many cells and organs are able to produce 1,25-dihydroxyvitamin D. As a result 1,25-dihydroxyvitamin D influences a large number of biologic pathways which may help explain association studies relating vitamin D deficiency and living at higher latitudes with increased risk for many chronic diseases including autoimmune diseases, some cancers, cardiovascular disease, infectious disease, schizophrenia and type 2 diabetes. A three-part strategy of increasing food fortification programs with vitamin D, sensible sun exposure recommendations and encouraging ingestion of a vitamin D supplement when needed should be implemented to prevent global vitamin D deficiency and its negative health consequences.
When did milk start to be vitamin D fortified?
This process was quickly embraced by the dairy processors and in the early 1930s essentially all milk in the United States and in most industrialized countries including Great Britain and other European countries had vitamin D fortified milk. The United States government also established an agency in 1931 whose goal was to promote sensible sun exposure of young children to prevent rickets and improve their bone health (Fig. 8).9,14Within a few years these interventions essentially eradicated rickets.8,17-19
What is the most stable form of previtamin D3?
Previtamin D3when made in a test tube exists in two confomeric forms, a 5,6-sec-cis-s-cis (czc) and a 5,6-sec-trans-s-cis (czt) form. The czt conformer is the most thermodynamically stable form and thus most of the previtamin D3when produced in a test tube exists as this conformer. This conformer however being stable cannot isomerize to vitamin D3. However the less thermodynamically stable conformer czc does undergo a 1–7 antarafacial sigma shift of a hydrogen from C-19 to C-9 causing rearrangement of the double bonds to form vitamin D3. As a result it takes several days in a test tube at room temperature and even at body temperature for the czt conformer to isomerize to the czc conformer which then is converted to vitamin D3(Fig. 12).6,7,26,27
What happens when 7-dehydrocholesterol is exposed to UVB?
When epidermal 7-dehydrocholesterol absorbs solar UVB radiation with energies of 290–315 nm (Fig. 10), it causes an activation of the double bonds causing them to rearrange and open up the B ring to form the seco-steroid (split steroid) previtamin D3(Fig. 11).25
What is the wavelength of sunlight?
During exposure to sunlight solar radiation with wavelengths of 290–315 nm penetrate into the skin and are absorbed by proteins, DNA and RNA as well as 7-dehydrocholesterol.1,2Most of this UVB radiation is absorbed in the epidermis and as a result when exposed to sunlight most of the vitamin D3that is produced in the skin is made in the living cells in the epidermis. This is the reason why after exposure to sunlight vitamin D3remains in the skin even when the skin is washed with soap and water immediately after the exposure to sunlight.
When did the Department of Labor start promoting sensible sun exposure in children?
Figure 8. Brochure of the US. Department of Labor promoting sensible sun exposure in children in 1931.
What is the importance of vitamin D?
Vitamin D, a fat-soluble vitamin , provides a variety of health benefits. It helps your body absorb calcium—one of the main building blocks of bone—and plays an important role in immune and muscle health. † ,1. Learn More: Vitamin D Immune System Benefits. Unfortunately, 95% of Americans do not consume enough Vitamin D from their diet alone, ...
How to take vitamin D?
To avoid the damaging effects of the sun’s rays, many health experts recommend the best way to take Vitamin D is through food and supplements. Not many vitamins get a nickname, but Vitamin D does. Known as the sunshine vitamin, this key nutrient can be obtained by the body through sunlight exposure.
How many people don't get enough vitamin D?
Unfortunately, 95% of Americans do not consume enough Vitamin D from their diet alone, 10 and research suggests that 40% of U.S. adults have a blood level indicating Vitamin D deficiency. 2 This can lead to a loss of bone density (which can contribute to fractures and osteoporosis) and rickets. 3 In addition, people who live in certain geographic locations (latitudes above 37 degrees north or below 37 degrees south of the equator) don't get enough UVB light from the sun most of the year to make enough Vitamin D. 4 Ditto for people who spend most of their time indoors.
What foods contain vitamin D?
The bad news: only a few foods naturally contain Vitamin D, including the following: 7. Fatty fish (think mackerel, salmon, trout, and tuna) and fish liver oils. Beef liver.
How does Vitamin D help your body?
Vitamin D helps your body absorb calcium, aids in supporting healthy teeth and bones, and plays an important role in immune and muscle health †. 40% of the U.S. population have a blood level indicating Vitamin D deficiency. You can get Vitamin D from three main sources: the sun, food, and supplements. To avoid the damaging effects of the sun’s ...
Does clothing help with vitamin D?
Any clothing covering these areas will prevent vitamin D conversion in the skin. You need Vitamin D for healthy teeth and bones. You can get Vitamin D from three sources—sun, food, and supplements. With concerns about protecting the skin, health experts recommend wearing sunscreen.
Does sun exposure cause skin cancer?
However, with concerns about skin cancer, unprotected sun exposure puts you at risk for several conditions that can permanently damage or disfigure your skin. 5 And unfortunately, wearing SPF limits your body’s ability to convert the sun’s rays into Vitamin D in the skin. Vitamin D Source: Food.
How much sun exposure is needed to produce vitamin D?
The truth is, it doesn’t take much sun exposure for the body to produce vitamin D. Even committed proponents of unprotected sun exposure recommend no more than 10 to 15 minutes of exposure to arms, legs, abdomen and back, two to three times a week, followed by good sun protection. That minor amount of exposure produces all ...
How to get vitamin D?
It’s pretty straightforward, actually. You can acquire vitamin D from a combination of diet and supplements. Fatty fish such as salmon, mackerel and tuna are especially good sources. Small amounts are also present in egg yolks, beef liver and cheese. And many common foods such as milk and orange juice are fortified with vitamin D. (Read labels, because foods are fortified only when they say they are.) It is possible, though not easy, to mix and match these foods to get the daily allowance of 600 International Units (IU) recommended by the Institute of Medicine and The Skin Cancer Foundation for the average person between the ages of 1 and 70. (400 IU is recommended for infants under age 1 and 800 IU is recommended for everyone over age 70.) In fact, if you’re willing to be a throwback to the past, just hold your nose and down a tablespoon of cod liver oil, which at 1,360 IU has more than twice the daily recommended intake of vitamin D.
What is a Healthy Level of Vitamin D?
If you’re having blood drawn for your annual checkup, ask your doctor to test your vitamin D level. On your lab report, here’s what your number means.
What is the active form of vitamin D?
When your skin is exposed to sunlight, it manufactures vitamin D. The sun’s ultraviolet B (UVB) rays interact with a protein called 7-DHC in the skin, converting it into vitamin D3, the active form of vitamin D.
How much sun rays does SPF 15 block?
An SPF 15 sunscreen filters out 93 percent of UVB rays, SPF 30 keeps out 97 percent , and SPF 50 filters out 98 percent. This leaves anywhere from 2 to 7 percent of solar UVB reaching your skin, ...
What is the SPF for melanoma?
Controlled studies have shown that regular use of an SPF 15 or higher broad-spectrum sunscreen reduces your chances of developing squamous cell carcinoma by about 40 percent, melanoma by 50 percent and premature skin aging by 24 percent.
How much vitamin D is in salmon?
One Boston University study showed that wild salmon had as much as 988 IU of vitamin D per serving. Farmed salmon had far less D. Ahi tuna is also a good choice.
What is the role of vitamin D in the body?
Vitamin D has other roles in the body, including reduction of inflammation as well as modulation of such processes as cell growth, neuromuscular and immune function, and glucose metabolism [ 1-3 ]. Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D. Many tissues have vitamin D receptors, and some convert 25 (OH)D to 1,25 (OH)2D.
Where does vitamin D come from?
Vitamin D obtained from sun exposure, foods, and supplements is biologically inert and must undergo two hydroxylations in the body for activation. The first hydroxylation, which occurs in the liver, converts vitamin D to 25-hydroxyvitamin D [25 (OH)D], also known as “calcidiol.”.
What vitamin deficiency causes rickets?
Associated with vitamin D deficiency, which can lead to rickets in infants and children and osteomalacia in adults. 30 to <50. 12 to <20. Generally considered inadequate for bone and overall health in healthy individuals. ≥50. ≥20. Generally considered adequate for bone and overall health in healthy individuals. >125.
Why is vitamin D important for muscle growth?
Vitamin D is also needed for the normal development and growth of muscle fibers. In addition, inadequate vitamin D levels can adversely affect muscle strength and lead to muscle weakness and pain (myopathy) [ 1 ].
How many people take vitamin D supplements?
The analysis of 2015–2016 data also showed that 28% of all individuals aged 2 years and older in the United States took a dietary supplement containing vitamin D [ 38 ]. In addition, 26% of participants aged 2–5 years and 14% of those aged 6–11 years took supplements; rates increased with age from 10% of those aged 12–19 years to 49% of men and 59% of women aged 60 and older. Total vitamin D intakes were three times higher with supplement use than with diet alone; the mean intake from foods and beverages alone for individuals aged 2 and older was 4.8 mcg (192 IU) but increased to 19.9 mcg (796 IU) when dietary supplements were included.
What is the serum concentration of 25?
Serum concentration of 25 (OH)D is currently the main indicator of vitamin D status. It reflects vitamin D produced endogenously and that obtained from foods and supplements [ 1 ]. In serum, 25 (OH)D has a fairly long circulating half-life of 15 days [ 1 ]. Serum concentrations of 25 (OH)D are reported in both nanomoles per liter (nmol/L) and nanograms per milliliter (ng/mL). One nmol/L is equal to 0.4 ng/mL, and 1 ng/mL is equal to 2.5 nmol/L.
Is vitamin D a test?
Screening for vitamin D status is becoming a more common part of the routine laboratory bloodwork ordered by primary-care physicians, irrespective of any indications for this practice [ 6, 51-53 ]. No studies have examined whether such screening for vitamin D deficiency results in improved health outcomes [ 54 ]. The U.S. Preventive Services Task Force (USPSTF) found insufficient evidence to assess the benefits and harms of screening for vitamin D deficiency in asymptomatic adults [ 6 ]. It added that no national professional organization recommends population screening for vitamin D deficiency.
Why is sunlight important for health?
Sunlight is good for our immune system, so it helps us to be less sickly and for those who have autoimmune diseases. Healthy lifestyle was mentioned earlier and sunlight actually will help us with them. Having morning walks will also helpful for the earlier you get a bit of sun exposure, the more likely it is that you fall asleep nice and early later on that day. The reason for this is that light influences and gives our body signal about night and day. Sunlight is also helpful in our diet for it keeps us from eating too much, so this is good for people who tend to binge eat.
Why is it bad to be out in the sun?
It is more now than before because the ozone layer which protects the earth from the UV rays is continuously depleting. The reason for this depletion is climate change and the use of chlorofluorocarbons. Because of this, overexposure in the sun can cause skin diseases such as sunburn, heat rash, and skin cancer. Because of this, timing is important. The best time to go out of the sun is before 10 in the morning and after 4 in the afternoon. Midday is when the sun is at its highest peak and the sun most harmful, so you may need to spend less time in the sun during this time. To avoid harmful consequences, always apply sunblock as protection. Bringing an umbrella is also advised.
What is the best vitamin for Alzheimer's?
One of the vitamins that we need is vitamin D. It affects greatly on our body and one of them is lowering our blood pressure. Scientists also discovered that sunlight could help induce more cell growth in the part of your brain responsible for memories (known as the hippocampus), so it helps our brain function and lessens the symptoms of Alzheimer’s Disease. Another factor is that lack of vitamin D increases the risk of cancer particularly breast and colon cancer.
Where is the sun not producing vitamin D?
Here are date ranges for a few cities and states showing when the sun is not at a high enough angle in the sky to produce Vitamin D at any time during the day: Los Angeles, California and Atlanta, Georgia: Both are at about 34 degrees latitude north of the equator.
What is the best time to produce vitamin D?
The time of day (midday has the highest potential to stimulate Vitamin D production), altitude (higher altitudes increase production potential), and cloud cover and pollution (both decrease production potential) also impact the time it takes to produce Vitamin D.
Why do UVB rays travel through the atmosphere?
Yet UVB is reflected and blocked by the atmosphere. The more atmosphere UVB rays have to travel through, the more UVB rays are prevented from reaching the surface of the earth; and the lower the sun is in the sky, the more atmosphere these UVB rays travel through. If the sun is low enough, UVB rays are completely blocked by the atmosphere before they even reach you, and Vitamin D production is not possible.
How to protect against sun damage?
The one thing you are able to do to help promote your defenses against the effects of sun exposure, without blocking your production of Vitamin D, is to eat a lot of foods with natural antioxidants in them–like colorful vegetables and fruits .
What is the highest level of vitamin D?
It is only when the sun is 50 degrees or higher that the amount of Vitamin D produced starts to become significant. And the higher the sun is above 50 degrees, the higher the rate of your Vitamin D production.
How high should the sun be above the horizon?
In order for the sun to stimulate your Vitamin D production, the sun needs to be at a minimum of about 50 degrees, or greater, above the horizon (90% would be directly overhead).
What happens when the sun is directly overhead?
If the sun is directly overhead, for instance, you would lie flat on the ground, and when the sun is at an angle you would lie at the angle that allows you to directly face the sun. It also doesn’t matter what part of your skin is producing your Vitamin D.