Vitamin D Types, Benefits, Food Sources and Best Supplements

Vitamin D has been getting a lot of buzz in recent months as people look to strengthen their immune systems against COVID-19, and its variants. A meta analysis of 23 studies, done by the International Journal of Clinical Practice, concluded that those with a Vitamin D deficiency are 3 times more likely to be infected with SARS-CoV-2 and develop complications from it. 

Why is Vitamin D so important?

Vitamin D is a fat-soluble vitamin (a hormone, in fact) that is essential to multiple body functions such as the absorption of calcium, magnesium, and phosphate. Getting adequate amounts of vitamin D can help protect against conditions such as heart disease high blood pressure, diabetes and immune disorders. Additionally, it may help prevent certain cancers, as well as regulate the parathyroid glands which typically 'pulls' calcium from the skeleton in order to keep blood calcium levels normal, causing bones to weaken and shrink.

According to recent research, it is thought that 41% of US adults are deficient in vitamin D and 93% aren't meeting the recommended daily intake of 400 IU. A vitamin D deficiency can be very problematic as it can cause depression, bone loss, fatigue, muscle cramps, bone & joint pain, and a weakened immune system.

What's the best way to get Vitamin D?

We all know that the main source of Vitamin D is the sun. However, there are some variables that affect how some of us absorb and convert sunlight into vitamin D. There is also the issue of having to wear sunscreen, which hinders the production of this essential vitamin.

But before you start questioning the use of your daily sunscreen, it is important to understand its tremendous benefits in preventing premature aging and skin cancers. While it is hard to find sunscreen alternatives, vitamin D, on the other hand, can be easily supplemented. Additionally, regardless of sunscreen use, skin color and age greatly impact our ability to get adequate levels of Vitamin D from sun exposure alone. Young people, as well as those with fair skin, are better able to convert sunlight into vitamin D than the rest of the population. Adults over 50 and those with darker skin tones have a much more difficult time absorbing sunlight and converting it into vitamin D.

A recent study done on 83 middle-aged women, supplementing with Vitamin D and Magnesium for 8 weeks, showed beneficial impact on muscle function, muscle strength, and possibly inflammation.

What are the best food sources of Vitamin D?

I am a big believer that diet should be the main source of nutrients. However, it's nearly impossible to get the necessary levels of vitamin D through diet alone. I have compiled a list of foods that contain vitamin D, but according to research, supplementation remains necessary, especially if you're vegan or lactose intolerant. Here are the top dietary vitamin D sources: 

 Food Serving Size Vitamin D Content in IUs (International units)
Cod Liver Oil 1 tbs 1360
Swordfish (cooked) 3 ounces 566
Salmon (Sockeye, cooked) 3 ounces 447
Tuna (canned in water) 3 ounces 154
Milk (Fortified) 1 cup 120
Yogurt (fortified with 20% Vitamin-D) 6 ounces 80
Sardines (canned in oil) 2 sardines 46
Egg Yolk 1 large 41


What to look for when considering Vitamin D Supplementation?

There are two types of vitamin D; D2 (prescription) and D3 (over the counter). Although you may be inclined to think that the prescription is the better one, research shows that D3 absorbs much more easily than its prescription counterpart.

What are the Main Sources of Vitamin D3 in Supplements?

There are two main sources:

Animal: Lanolin is the main source, which comes from sheep's wool (it is both; high quality & inexpensive)

Vegan: mainly derived from Algae or Lichen.

What are the Best Vitamin D Supplements?

When it comes to supplements, I cannot stress this enough; quality matters! Being a non-pharmaceutical product (non-prescription), supplements fall under 'conventional' food products, hence remain unregulated by the FDA. This means that companies can launch supplements without review or approval by the Food and Drug Administration. That is why it is paramount that you do your research and select reputable brands.

Being a skincare expert, I personally prefer taking Vitamin D3 in conjunction with Vitamin K2. The latter has been shown to help direct calcium from arteries (which can be problematic), to the bones where it is needed most. This can result in bone loss prevention. Aside from the obvious health benefit, Vitamin K2 can be a great contributor to maintaining a youthful appearance as it helps maintaining facial bone structure leading to less skin sagging and signs of aging.

Here are my top picks:

SR Plant-based Vegan Vitamin D3 (5000 IU) + K2 (1000mcg) with Organic Virgin Coconut Oil 

vegan certified and non-GMO combo supplement by Sports Research. It combines 5,000 IU of vegan vitamin D3 from lichen with 100 mcg of vitamin K2 derived from chickpeas.





High Potency Vitamin D for Immune & Bone Support

Non-vegan: This is non-GMO verified, gluten & soy- free, from lanolin, made with a kosher gelatin and vegetable glycerin capsule. Offers 5000IUs per one capsule serving and a one year supply.             





MegaFood, Vitamin D3 2000 IU 

Vegetarian. Contains a food and herb blend of organic brown rice, organic parsley leaf, organic broccoli, organic carrot and organic beet root. Non-GMO Project Verified, tested for 125+ herbicides and pesticides, free of gluten, dairy, soy; Certified B Corp; Certified Glyphosate Residue Free; Certified Kosher.




NOW Supplements, Vitamin D-3 5,000 IU, Natural Mint Flavor

Chewable option. Quality GMP Assured, Kosher, Soy Free, Gluten Free. Vitamin D3 derived from Lanolin.





 In conclusion, Vitamin D is a key player in maintaining overall health benefiting, bones, joints, hair, nails and skin. It is nearly impossible to get adequate amounts from sun exposure and diet, especially for vegans. Supplementation is deemed necessary to maintain proper immune function.

 Be well. Be safe. Be beautiful!


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As a blogger, my content may include affiliate links from advertisers. I may earn a small commission from actions readers take on these links such as a purchase, or subscribe. All my recommendations are based on my own research and personal trust in the products that I share. I am not a doctor or nutritionist. Please consult with your practitioner prior to using any products recommended.