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How Does The Sun Give You Vitamin D

What Is Vitamin D

How Does Our Skin Turn Sunlight Into Vitamin D?

Vitamin D is not one chemical but many. The natural type is produced in the skin from a universally present form of cholesterol, 7-dehydrocholesterol. Sunlight is the key: Its ultraviolet B energy converts the precursor to vitamin D3. In contrast, most dietary supplements are manufactured by exposing a plant sterol to ultraviolet energy, thus producing vitamin D2. Because their function is almost identical, D2 and D3 are lumped together under the name vitamin D but neither will function until the body works its magic .

How your body makes vitamin D

The sun’s energy turns a chemical in your skin into vitamin D3, which is carried to your liver and then your kidneys to transform it to active vitamin D.

The first stop is in the liver, where vitamin D picks up extra oxygen and hydrogen molecules to become 25-hydroxyvitamin D, or 25D. This is the chemical that doctors usually measure to diagnose vitamin D deficiencies. But although 25D is used for diagnosis, it can’t function until it travels to the kidney. There it acquires a final pair of oxygen and hydrogen molecules to become 1,25 dihydroxy vitamin D scientists know this active form of the vitamin as 1,252D, or calcitriol, but for ordinary folks the name vitamin D is accurate enough.

How Much Sun Do We Need For Healthy Bones

The best source of vitamin D is UVB radiation from the sun. UV radiation levels vary depending on location, time of year, time of day, cloud coverage and the environment.

For most people, adequate vitamin D levels are reached through regular incidental exposure to the sun. When the UV Index is 3 or above , most people maintain adequate vitamin D levels just by spending a few minutes outdoors on most days of the week.

In late autumn and winter in some southern parts of Australia, when the UV Index falls below 3, spend time outdoors in the middle of the day with some skin uncovered. Being physically active also helps boost vitamin D levels.

Who Should Take Vitamin D Supplements

Vitamin D is one of the most common nutrient deficiencies. According to the US National Center for Health Statistics, an estimated 70% of US citizens may be considered vitamin D deficient. In addition, according to the Journal of Clinical Endocrinology and Metabolism, elderly populations are particularly at risk of vitamin D deficiency, in part because aging depletes our bodies natural ability to naturally produce and absorb vitamin D.

Vitamin D supplements are ideal for people that are looking to maintain or increase their current vitamin D level. If you are deficient in vitamin D, a supplement will likely be the quickest and most effective way to increase your vitamin D levels.

When selecting a vitamin D supplement, you should search for a high quality product with transparent labeling. There are two types of vitamin D: D2 and D3 . If your doctor does not have a preference, you may want to begin with D3 because it is the naturally occurring form and it may raise your vitamin D level more effectively. If you have minor to moderate deficiency, a daily dose between 6001,000 IU will likely work well to negate your deficiency.

Did you know that natural supplement forms of D3 come from two sources? Vegetarian D3 is most commonly derived from sheep lanolin and vegan D3 can be derived from algae. These options make it easy to find a high quality supplement that works well for you.

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How Much Vitamin D Do I Need

From about late March/early April to the end of September, the majority of people should be able to make all the vitamin D they need from sunlight on their skin.

Children from the age of 1 year and adults need 10 micrograms of vitamin D a day. This includes pregnant and breastfeeding women, and people at risk of vitamin D deficiency.

Babies up to the age of 1 year need 8.5 to 10 micrograms of vitamin D a day.

A microgram is 1,000 times smaller than a milligram . The word microgram is sometimes written with the Greek symbol followed by the letter g .

Sometimes the amount of vitamin D is expressed as International Units . 1 microgram of vitamin D is equal to 40 IU. So 10 micrograms of vitamin D is equal to 400 IU.

Vitamin D And Sunlight

When is the best time to get vitamin D from the Sun?

Vitamin D is a nutrient in your body that may come from many sources. Vitamin D is a fat-soluble vitamin that exists in one of two forms: D2 and D3 . The benefits of Vitamin D are widely known. Vitamin Ds influence on bone growth and strength may be the most notable benefit. As mentioned above, there are various sources of vitamin D, including food, sunlight, and dietary supplements. For many people, it is most ideal to get vitamin D from a combination of these sources. Depending on where you reside, however, it may be challenging to get vitamin D from the sun. Many locations experience hundreds of days of cloud cover each year. Therefore, your food and supplement intake will be a very important consideration.

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When Do I Need Sun Protection

Sun protection is recommended when the UV Index is 3 or above, or when spending extended periods of time outdoors. Sunscreen should be incorporated into your daily morning routine on these days.

UV radiation levels in northern areas of Australia are generally higher than in southern areas, so in some parts of the country, sun protection is needed all year round, whenever the UV Index is 3 or higher. In these areas, it is safe to go outside without sun protection early morning and late afternoon when the UV Index falls below 3.

In some southern areas of Australia, there are times of the year when sun protection may not be necessary, generally late autumn and winter. If you live in an area where the UV Index falls below 3 during these months, you do not require sun protection, unless you are at high altitudes or near highly reflective surfaces like snow, work outdoors, or are outside for extended periods.

To check UV levels and the times sun protection is required, look at the UV Index in the weather section of your daily newspaper, on the Bureau of Meteorology website or download Cancer Councils free SunSmart app to your mobile device. When UV levels are below 3 no UV Alert is issued.

Several studies have shown that sunscreen use has minimal impact on Vitamin D levels over time.

How Long Do I Need To Be In The Sun To Get Vitamin D

There is no evidence that states the ideal amount of time for a person to be exposed to the sun. A persons reaction to sunlight can differ based on skin tone, genetics, and many more factors. A daily recommendation of 30 minutes is often adequate for most adults. This length of time enables you to reap the benefits of sunlight exposure without putting yourself at great risk for future health conditions. There is some evidence that midday sunlight exposure is most ideal since the sun is at its highest point. Therefore, you can spend less time in the sun but enjoy greater benefits since the sun is strongest midday.

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/10harmful Effects Of Too Much Sunlight

Though sunlight is a great source of vitamin D, too much sun can be dangerous for your skin. Here are some consequences of getting exposed to too much sunlight.

Sunburns – This is one of the most common side effects of too much sunlight. Symptoms of sunburn include redness, swelling, pain, tenderness or blisters on the skin.

Eye damage – Too much exposure to UVB rays can damage the retina, which can increase the risk of cataracts.

Ageing skin – Spending too much time in the sun can cause your skin to age faster. Some people develop wrinkles and their skin becomes loose and leathery.

Heatstroke – Heatstroke also called sunstroke is a condition in which the body’s core temperature rises due to too much sun exposure.

Skin cancer – Too much UVB light is a major cause of types of skin cancers.

You Might Benefit From Vitamin D In The Darker Months

The Sun’s Benefits Are Way More than Vitamin D

Posted July 31, 2017

Sun-bathers know how relaxing it can be to lie around drinking up light. Our bodies make Vitamin D from sunlight, which is linked to mood.

Some people never go outside without a sunscreen or keep themselves entirely covered up. Actually, your body produces the first step in making Vitamin D well before your skin turns pink. Theres no need to get tanned or burned.To get your daily dose of sunlight, go outside with at least your face exposed for about 10 to 20 minutes during mid-day. People with darker skin need the most light and may need more time.

Although you can be deficient in Vitamin D at any age, your risk increases as the years go by, and your body becomes less efficient at making Vitamin D and using it. Food alone wont fill a deficiency: Milk, oily fish and egg yolks all contain Vitamin D, but not enough. It could take dozens of glasses of milk to match the Vitamin D generated by ten minutes of summer sun on bare skin.

There’s plenty of evidence that lack of sunlight can drag your mood down. People who live in northern climates are more likely to seek out information about depression online during the winter, one study found. Low blood levels of vitamin D are linked to more signs of depression. In other research, people who attempted suicide had much lower vitamin D levels than other depressed people who werent suicidal or a group of healthy controls. Vitamin D lowers one kind of inflammation, which has been linked to suicide.

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How To Get Enough Vitamin D

So, what are some keys to getting vitamin D in a way thats healthy for your skin? Well, here are a few important things to keep in mind:

Know Your Skin: Its important for you to be aware of how sensitive your skin is. Different people can go for different amounts of time in the sun without getting harmed by UV rays, but it depends on a number of factors.

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People with darker skin tend to be less affected by UV radiation, but if you have lighter skin, you may only be able to stay in the sun for a short while without sunscreen. Be aware of your bodys limits, and remember to use sun protection if you plan to be outside for more than 10-30 minutes, depending on your individual sensitivity.

Midday Is Best: The best time to get healthy sunlight is during midday, around noon. This is the time of day when you can safely give yourself 10-30 minutes of unprotected exposure to sunlight, again depending on the sensitivity of your skin.

To boost your vitamin D levels, try stepping out into the sun for a few minutes each day around noon. Why not a stroll after lunch?

Know When to Use Sunscreen: Sunscreen may interfere with your bodys ability to produce vitamin D from sunlight, so its a good idea to give yourself a few minutes of sun exposure without it. But this is why its important to know your own body.

Supplements : Vitamin D


Vitamin D is involved in many of your bodys functions. There are two forms in the diet, D2 and D3. It can also be produced in your skin when exposed to sunlight.

Vitamin D deficiency is a problem all over the world.

However, its pervasive in young women, infants, older adults, and people who have dark skin .

About 42% of the U.S. population is vitamin D deficient. However, this rate rises to 82% in Black people and 70% in Hispanics, which systemic problems likely play a role in .

If you have access to strong sun all year, then occasional sun exposure may be enough to fulfill your vitamin D requirements.

However, if you live far north or south of the equator, your vitamin D levels may fluctuate depending on the season. The levels may go down during the winter months due to a lack of sufficient sunlight .

In that case, you may need to rely on your diet for vitamin D as well as on vitamin D thats stored in body fat (

  • intensify bone loss
  • increase the risk of fractures

In children, a severe vitamin D deficiency can cause delays in growth and rickets, a disease where the bones become soft.

Furthermore, vitamin D deficiency is linked with several cancers, type 1 diabetes, multiple sclerosis, high blood pressure, and thyroid problems .


Vitamin D deficiency is prevalent worldwide but occurs at higher rates in specific populations. A deficiency in vitamin D is linked to various health problems.

How much vitamin D you need depends on many factors. These include:

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Breaking The Old Rules

Vitamin D is one of the 13 vitamins discovered in the early 20th century by doctors studying nutritional deficiency diseases. Ever since, scientists have defined vitamins as organic chemicals that must be obtained from dietary sources because they are not produced by the body’s tissues. Vitamins play a crucial role in our body’s metabolism, but only tiny amounts are needed to fill that role.

Although vitamin D is firmly enshrined as one of the four fat-soluble vitamins, it is not technically a vitamin. True, it’s essential for health, and only minuscule amounts are required. But it breaks the other rules for vitamins because it’s produced in the human body, it’s absent from all natural foods except fish and egg yolks, and even when it’s obtained from foods, it must be transformed by the body before it can do any good.

As our habits change, most of us cannot rely on our bodies to produce vitamin D the old-fashioned way. Instead, we increasingly depend on artificially fortified foods and pills to provide this vital nutrient. Coming full circle in the modern world, this substance may actually come to fit the technical definition of a vitamin.

Other Sources Of Vitamin D

Vitamin D: The sunshine hormone

The sun, some meals, and vitamin D supplements are all good sources of vitamin D.

The recommended daily consumption of vitamin D from food or supplements in the United States is as follows:

  • Children and teenagers: 600 international units or 15 micrograms .
  • Adults up to the age of 70 years old: 600 IU or 15 mcg.
  • Adults aged 71 years old and over: 800 IU or 20 mcg.
  • During pregnancy and breastfeeding: 600 IU or 15 mcg.

Vitamin D can also be present in a few foods such as:

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So Can We Synthesise Vitamin D From Behind A Window

Well, no thats where the problem lies. In fact, vitamin D biosynthesis is initiated in the skin when UVB rays react with 7-dehydrocholesterol to produce pre-vitamin D3, which is then isomerised into cholecalciferol .

Now, windows let UVA rays through but they block UVB. So while the sun is still able to damage the skin through a pane of glass by generating oxidative stress which accelerates skin ageing, it cannot provide any benefits. We can neither synthesise vitamin D nor get a suntan from behind a window .

Whats more, the ratio between UVA and UVB from the sun varies throughout the year . When we who live in the northern hemisphere go outside in the winter months, we receive very little UVB, but a lot of UVA. Conversely, the UVB percentage increases in summer though UVB has its bad side too. It poses a risk to our skin and health in general, so its important to be careful about directly exposing your skin to the sun. To give itself some protection from UVB, the body also makes melanin which produces a kind of barrier in the form of a suntan.

Plan Your Sun Exposure If Possible

Now that I know that there are only certain times that I can get Vitamin D from the sun, Im going to try to get most of my sun exposure during those times.

Does that mean Im going to avoid the sun like the plague during the times when I cant get Vitamin D? No, Im not going to go crazy about it. Sometimes its just not possible or practical to stay out of the sun during the times when its less than 50 degrees above the horizon.

I also think theres something to be said for just the feeling of warmth and light you get when youre out in the sun, even if youre not getting any beneficial Vitamin D from it. It does mean, though, that Im not going to purposely sit outside with the intent of sunbathing unless Ive checked first to make sure that its even possible for me to get any Vitamin D at all.

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New Light On The Sunshine Vitamin

It used to be simple: just get a “healthy” tan and your body will make all the vitamin D it needs. Desk jobs and sunscreen have changed all that, just as research is underlining the importance of vitamin D and suggesting its possible role in preventing many health problems. That makes vitamin D a dilemma of modern life that has a modern solution: eating fish and drinking some low-fat fortified milk, along with judicious doses of vitamin D supplements.


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