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Known as the “sunshine vitamin,” vitamin D is among the few rockstar nutrients that have garnered national attention and research funding within the last 10 years. Studies continue to show its effectiveness for promoting normal blood sugar, immune health, and positive mood. Sales of vitamin D supplements have skyrocketed thanks to the surge of coverage in the media concerning this miracle nutrient. Despite this, vitamin D remains elusive to many.
Inadequate intake of vitamin D has become a problematic issue for people all over the world and roughly half suffer from vitamin D deficiency. Perhaps you’ve looked into supplementing your own vitamin D needs but were stonewalled by the options specifically, vitamin D3 vs. vitamin D2. The confusion between the two is very common let’s see if we can clear it up.
What Are The Main Differences Between Vitamin D And D3
The term vitamin D is kind of a misnomer because you will not find anything labeled simply as vitamin D in a pharmacy vitamin aisle. Rather, your choices will be vitamin D2 or vitamin D3 . Generally, when one mentions vitamin D, the implied selection is vitamin D2. For the purpose of this article, when vitamin D is mentioned, it will refer to vitamin D2. The names can be confusing, because many times, patients go into the pharmacy looking for vitamin D and are surprised that there is a D2 and a D3.
Vitamin D comes from plant sources, such as wild mushrooms, as well as fortified foods, such as milk or cereal products. Its strength is typically measured in international units, which is abbreviated as IU on labeling. The 50,000 IU capsules are prescription only, while lower strengths are available over-the-counter. Vitamin D is less expensive to produce and therefore is the form most commonly found in fortified food products.
Vitamin D3 mainly comes from animal sources such as fish oil, fatty fish, liver, and egg yolks. When your skin is exposed to sunlight, it produces vitamin D3. For this reason, it is sometimes referred to as the sunshine vitamin. Its strength is also measured in international units. All forms of vitamin D3 are available over-the-counter.
|Main differences between vitamin D and D3
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What To Look For
The main source of vitamin D comes from exposure to the sun. The American Academy of Dermatology advises that we obtain vitamin D from foods and supplements rather than UV exposure, because of the risk of skin cancer.
However, other expert bodies and research on vitamin D suggest that spending 5 to 30 minutes exposed to the sunlight , at least twice weekly, if not every day, with the face, arms, hands, and legs exposed without sunscreen can produce sufficient vitamin D synthesis.
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D: K2the Birth Of A Superhero Combo
Speaking of teamwork, vitamin D3s natural partner is vitamin K2. The genius of this combo begins with proper respect for D3s function of powerfully enhancing calcium absorption. Recent research has shown that excessive calcium intake alone can be harmful to the body. The additional calcium must be correctly utilized or it can show up in the wrong places and cause disease.
This is how very high doses of cholecalciferol kills rodents: excessive calcium uptake, deposition, and interference with normal cardiac and renal function. By conscientiously using vitamin K2 in conjunction with D3, this issue of metastatic calcium is thoroughly avoided.
Vitamin K2 activates several important proteins in the body. Henrick Dam, a Danish researcher, discovered vitamin K in 1939 . Because the Danish word for blood clotting was koagulation, Dam named the molecule vitamin K. Vitamin K is essential for the functioning of eight proteins involved in blood clotting.
A major medical misunderstanding surrounds vitamin K. Most doctors believe that vitamin K causes coagulation. It is true that babies born deficient in K need injections of it to restore coagulation. It is also well known that Coumadin, another rodenticide, poisons vitamin K coagulation function which does cause thinning of the blood. At really high doses this can kill a rat. At properly controlled doses, it can dissolve a threatening blood clot in a human patient.
Assists In Immune System Function
During cold and flu season, Vitamin D helps our immune system keep up with the demand! White blood cells, our bodies defense against sickness, have a vitamin D receptor on their surface which helps to keep our system in complete balance. This balance is vital to a healthy immune system that is ready to fight when needed. According to Centre Spring MD, studies have shown that vitamin D deficiency is associated with increased susceptibility to infection, and can impair the maturation of healthy white blood cells, which help the body to fight illness.
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Vitamin D Recommended Daily Intake
The recommended dose for vitamin D varies by age. Experts recommend a daily dose of:
400 IU for infants under 12 months
600 IU for people between ages 1 and 70
800 IU for people who are 71 years and older
As you can see, these doses are far less than the 50,000 IU concentrated supplements often recommended for people with low levels of vitamin D.
What Are The Health Benefits Of Vitamin D
There are a few purported benefits of vitamin D that are either unconfirmed or that do not have enough supporting evidence. These include using vitamin D to prevent and treat diabetes, hypertension, and multiple sclerosis. There has also been conflicting evidence as to whether vitamin D supplementation can improve life expectancy. One analysis initially found that vitamin D supplementation was associated with an improved life expectancy, but a second review of the data did not find this association . More studies need to be conducted to better determine whether vitamin D supplementation actually confers any sort of longevity benefit.Many studies have looked into the efficacy of vitamin D supplementation for the treatment of depression. One review found that, amongst the studies that did not have flaws, vitamin D supplementation is associated with improvement of depression .Vitamin D also has the following health benefits, which is why it was chosen to be an ingredient in the Roman Dailies:
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What Are The Benefits Of Liquid Vitamin D
Vitamin D has several different varieties vitamin D-3 is the type made naturally by human skin when its exposed to the sun. Vitamin D-3 can be found in egg yolks, fish, beef, dairy and some fortified foods. It is also found in supplement form, and it is used for a variety of health promoting purposes. Although you can buy vitamin D-3 supplements in tablet, capsule and liquid form, the liquid has some advantages over the pill.
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Vitamin D Metabolites As Immune Modulators In Autoimmune Diseases: Animal Models And Human Data
Later these animal models were translated to humans as the European Diabetes Centers EURODIAB study showed a significant decrease in T1D onset in children receiving vitamin D supplementation . The first major birth-cohort study was done in Finland and resulted in a staggering 80% reduction in T1D onset in 10,336 children receiving vitamin D supplementation before the age of 1 year, irrespective of the dose of supplementation . Likewise, in MS, low neonatal 25-D3 concentrations are associated with an increased risk of disease incidence . Based on cohort data of more than 7 million persons, it was proven in MS that vitamin D supplementation resulted in significant lower disease incidence .
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What Is Vitamin D And How Do I Get It
Vitamin D is an important ingredient in many different cellular processes in the body. It is well-known for keeping our bones strong, but it also plays a role in other functions, including:
Calcium and glucose metabolism
There are two natural sources of vitamin D:
1) Food: There are only a small number of foods that naturally contain vitamin D. Some of the best sources include:
It is more common to find foods that are artificially fortified with vitamin D, like cereals and milk.
2) Sunlight: Our body can actually make its own vitamin D! When we are exposed to ultraviolet light from the sun, our skin uses the sunlight to make the vitamin from scratch.
Most people have adequate levels of vitamin D through these two sources. After all, it takes only 5 to 30 minutes of sun exposure a day for your body to make enough of it. But some people choose to take supplements to keep their vitamin D levels at a normal level especially if they have or are at risk for low levels of it.
How Much You Need And How Best To Actually Get It
According to the FDA, the Recommended Dietary Allowance for vitamin D is 600 IU for adults. Those over 70 require more, so the RDA for them is 800 IU. However, it can be hard to meet this dose in winter. Vitamin D3 isnt found in many foods, but some dairy products, cereals, and grains are fortified with vitamin D3 to help people increase their intake, says Craig Elbert, CEO of Care/of in New York City.
Fatty fish such as salmon, tuna, and sardines as well as eggs and shiitake mushrooms are other dietary sources of vitamin D3, but its important to note that the metabolism of vitamin D3 from our foods may be dependent on adequate iron status, says Texas nutrition expert Pam Machemehl-Helmly, founder and chief science officer of Wellnicity. Test your blood levels for vitamin D and iron to know your status.
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The Final Verdict On Vitamin D
No bones about it, the endocrinologists we interviewed agree with our dermatologist.
“Just being outdoors, you get a fair amount of sun exposure and some sun-related generation of vitamin D, says Dr. Insogna. Because skin cancer, particularly melanoma, can be such a devastating disease, it’s best to use sunblock when outdoors in strong sunlight for any prolonged length of time. Because this may limit the amount of vitamin D you get from sun exposure, make sure your diet includes sources of vitamin D from foods or supplements, he says.
Both your skin and your bones will thank you.
Dealing With Vitamin D2 Deficiency Beyond Supplements
Fortunately, vitamin D2 deficiency can easily be prevented and treated through adequate supplementation.
However, beyond this, the following lifestyle factors can also help.
1. Diet Changes
A diet change is a solid step towards battling any nutrient deficiency, especially for people who dont have any malabsorption issues.
Choosing the right ingredients to incorporate into your meal planning and food choices is key.
The best way to absorb and incorporate more vitamin D2 into a persons diet, though, is to switch to a plant-rich diet.
Fruits and vegetables offer the most potential as potent sources of vitamin D2.
In an effort to prevent the prevalence of vitamin D deficiency, it should also be noted that the Food and Drug Administration fortify certain food products with vitamin D.
2. Sun Exposure
Making time to go out in the sun, especially in the mornings, can also mark a significant change in a persons vitamin D levels.
In particular, our skin is equipped to produce vitamin D when it is exposed to the ultraviolet B radiation that the sun emits. There are different factors to consider, though.
For instance, specific locations that are closer to the equator will definitely get to enjoy more sun exposure. Air pollution and cloud cover can also prevent one from getting quality UVB rays.
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What Is Vitamin D
Vitamin D is a fat-soluble vitamin that promotes the absorption of calcium, regulates bone growth and plays a role in immune function.
Your skin produces vitamin D when its exposed to sunlight. However, if you spend most of your time indoors or live at a high latitude, youll need to get this vitamin from your diet.
Good dietary sources include fatty fish, fish oils, egg yolk, butter and liver.
However, it may be difficult to get adequate amounts of this vitamin from your diet alone, as rich natural sources are rare. For these reasons, its common for people to not get enough.
Luckily, many food manufacturers add it to their products, especially milk, margarine and breakfast cereals. Supplements are also popular.
To prevent deficiency symptoms, make sure to eat vitamin D-rich foods regularly, get some sunlight or take supplements.
Since vitamin D is fat-soluble, it is better to choose oil-based supplements or take them with food that contains some fat (
Since vitamin D2 is cheaper to produce, its the most common form in fortified foods.
Summary Vitamin D3 is only found in animals, while vitamin D2 comes from plant-sourced foods.
Vitamin D Boosts Weight Loss
Consider adding vitamin D supplements to your diet if youre trying to lose weight or prevent heart disease. You can find a great selection of vitamin D supplements on .
In one study, people taking a daily calcium and vitamin D supplement were able to lose more weight than subjects taking a placebo supplement. The scientists said the extra calcium and vitamin D had an appetite-suppressing effect.
In another study, overweight people who took a daily vitamin D supplement improved their heart disease risk markers.
Many factors can affect your ability to get sufficient amounts of vitamin D through the sun alone. These factors include:
- Being in an area with high pollution
- Using sunscreen
- Spending more time indoors
- Living in big cities where buildings block sunlight
- Having darker skin.
These factors contribute to vitamin D deficiency in an increasing number of people. Thats why its important to get some of your vitamin D from sources besides sunlight.
The symptoms of a vitamin D deficiency in adults include:
- severe bone or muscle pain or weakness that may cause difficulty climbing stairs or getting up from the floor or a low chair, or cause you to walk with a waddling gait
- stress fractures, especially in your legs, pelvis, and hips
Doctors can diagnose a vitamin D deficiency by performing a simple blood test. If you have a deficiency, your doctor may order X-rays to check the strength of your bones.
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How Is Vitamin D Deficiency Treated
The goals of treatment and prevention are the sameto reach, and then maintain, an adequate level of vitamin D in the body. While you might consider eating more foods that contain vitamin D and getting a little bit of sunlight, you will likely be told to take vitamin D supplements.
Vitamin D comes in two forms: D2 and D3. D2, also called ergocalciferol, comes from plants. D3, also called cholecalciferol, comes from animals. You need a prescription to get D2. D3, however, is available over the counter. It is more easily absorbed than D2 and lasts longer in the body dose-for-dose. Work with your doctor to find out if you need to take a vitamin supplement and how much to take if it is needed.
Conditions Treated By Vitamin D And D3
Vitamin D2 as a prescription is used to treat hypoparathyroidism , vitamin D resistant rickets, and hypophosphatemia . It is commonly used for vitamin D insufficiency in both its prescription and over-the-counter formulations. The FDA does not approve treatment claims for over-the-counter vitamin supplements, therefore, even though this use is very common, it is considered off-label.
All forms of vitamin D3 supplements are available over-the-counter, and therefore are not FDA approved to make treatment claims. However, vitamin D3 is commonly used off-label to treat hypoparathyroidism and vitamin D deficiency, as well as for osteoporosis prevention.
In March of 2020, the World Health Organization declared a global pandemic in the wake of the spread of SARS-CoV-2, more commonly known as COVID-19. Due to a lack of clear treatment guidelines and a waiting period for the vaccine to be available, the focus shifted to boosting our natural immune system. Vitamin D became a key player in our fight against COVID-19.
Preliminary studies have shown that Vitamin D reduced ICU admissions in COVID-19 patients and improved overall outcomes.
Various uses of vitamin D supplementation are listed in the table below. You should always seek medical advice before beginning vitamin D supplementation.
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How Often Do You Need To Get Your Vitamin D Levels Checked
Doctors do not usually order routine checks of vitamin D levels, but they might need to check your levels if you have certain medical conditions or risk factors for vitamin D deficiency. Sometimes vitamin D levels can be checked as a cause of symptoms such as long-lasting body aches, a history of falls or bone fractures without significant trauma.
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