Vitamin D, Am I Getting Enough?

Vitamin D, Am I Getting Enough?

During the colder winter months, it becomes difficult and sometime impossible to go outside. Besides losing quality time with nature, not being outside deprives us of some essential nutrients; like vitamin D. In western society vitamin D deficiency is common, yet supplementation of vitamin D is slacking. So the question becomes, what is vitamin D and am I getting enough of it ?In this blog we’ll answer these questions and more.

What Is The Role ?

As we mentioned before vitamin D is an essential nutrient, but it is present in very few foods. Vitamin D is associated with bone health due to its ability to promote calcium absorption. However this is not all vitamin D does. It also plays a role in cell growth, immune function, and the reduction of inflammation; among other functions(1,2,3). It is a fat-soluble vitamin, meaning it is absorbed along with fats in your diet and can be stored in the body’s fatty tissue. Because of this generally a smaller amount is needed to maintain good health. But there are a couple of factors that can undermine how it is absorbed. 

vitamin d absorb

What Effects My Absorption Ability

  1. Where You Live
    1. If you live closer to the equator, you likely have higher absorption of the vitamin through the sun’s UVB light. Consequently, areas further from the equator, like New York, receive less UVB light exposure. During the fall to winter months, the days become shorter and so does the emission of UVB rays.(4)
  2. Melanin
    1. Melanin is the substance in your skin that makes it dark. UVB rays penetrate the skin in order to kick-starts the body’s vitamin D production. These two substances compete, and as a result darker-skinned people generally require more UVB light to produce the same amount of vitamin D as lighter skinned people.
  3. Temperature
    1. Warm skin is a better coefficient for vitamin D production than cooler skin. So hotter days will likely produce more vitamin D than colder ones.
  4. Age
    1. As you age the substance in your skin that converts UVB rays decreases. Due to this, older people may not produce vitamin D as efficiently as younger people.
  5. Co-factors
    1. Making sure you have sufficient vitamin D co-factors( vitamin K2, magnesium, boron, and zinc) is essential for optimal production of the vitamin and overall health. For example, magnesium is essential in the metabolism of vitamin D. However when you take large doses of vitamin D, you can induce severe depletion of magnesium (5).

vitamin d recommended

How Much is Recommended ?

Recommendations from the US Institute of Medicine suggest that an average daily intake of 400–800 IU, or 10–20 micrograms, is adequate for 97.5% of individuals (6,7). However this value may change depending your exposure to sunlight, as well as some of the factors above. In some people levels of 1000–4000 IU, or 25–100 micrograms, is considered sufficient(8). The bottom line is that if you feel you may not be getting adequate amount of any vitamin, you should see your doctor and request to get a blood test.

The Institute of Medicine (IOM) and the Nordic Nutrition Council base their recommendations on the following blood levels (9, 10):

  • Sufficient: 25(OH)D greater than 20 ng/ml (50 nmol/l).
  • Insufficient: 25(OH)D less than 20 ng/ml (50 nmol/l).
  • Deficient: 25(OH)D less than 12 ng/ml (25 nmol/l).

Vitamin D sun

Is Getting Vitamin D From The Sun Enough?

D vitamins exists in two forms. Vitamin D2 is obtained from the UV irradiation of the yeast sterol ergosterol and is found naturally in sun-exposed mushrooms. UVB light from the sun strikes the skin, and humans synthesize vitamin D3, so it is considered the most “natural” form(11).

Despite this, you may not be receiving enough of the vitamin from the sun. If you live an area further from the equator and spend most of you day indoors, you may want look in supplementing your vitamin D intake with foods and supplements.

Although the sun is considered the most natural source for the vitamin, Dermatologist advise against tanning and usage of tanning bed on basis of vitamin D. To protect your skin make sure to use sunblock when outdoors during strong sunlight and for prolonged lengths of time (12).

vitamin d-food

What Are Food Sources?

Eating plenty of vitamin-D-rich foods is a great way to make sure you get enough of this important nutrient. Especially if you spend most of your day indoors.

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Vitamin D Supplements

optimen vitamin d

If you haven’t been prescribed by your doctor to take vitamin D as a standalone supplement but don’t feel you have an adequate amount of vitamin D, you can consider taking a multi vitamin.

  • Opti Men By Optimum Nutrition has 1,500 IU per 3 tablets
  • Opti-Women By Optimum Nutrition has 600 IU per 2 tablets
  • Animal Pak By Universal Nutrition has 680 IU per 2 packs
  • Daily Formula By Universal Nutrition has 400 IU per Tablet

vitamin d3

When selecting a vitamin D standalone, its important to know which IU your doctor recommends for you. More IUs is not necessarily better.

  • Now Foods Vitamin D ranges from 400 IU to 10,000 IU
  • Healthy Origins Vitamin D offers a 10,000 IU supplement at 360 softgels per bottle
  • 21st Century  Vitamin D offers a 5,000 IU supplement as 360 tablets per bottle
  • Kirkland Vitamin D offers a 2,000 IU supplement at 600 softgels per bottle


Can I Have Too Much ?

As we mentioned above, the recommended dosage has fluctuated over the years. But according to Yale Medicine, 600 IU per day should enough for healthy individuals. For people above the age of 70, 800 IU should be sufficient (12).

Too much of this vitamin can result in vitamin D toxicity, also called hypervitaminosis D. Toxicity is usually caused by megadoses of vitamin D supplements — not by diet or sun exposure. The main consequence of this toxicity is a buildup of calcium in your blood (hypercalcemia), which can cause nausea and vomiting, weakness, and frequent urination. Symptoms might progress to bone pain and kidney problems, such as the formation of calcium stones.

Treatment includes stopping vitamin D intake and restricting dietary calcium (13).


Please Note

†The intention of the information above is for reference only. While we attempt to keep our information accurate, we cannot guarantee it is an accurate representation of the latest formulation of the product. If you have any concerns, please visit the vendors web site. The information above are the views of the product’s manufacturer, not the views of Same Day Supplements. The Food and Drug Administration has not evaluated these statements. The intention of this product is not to diagnose, treat, cure or prevent any disease or illness.