Research-Based

Best Vitamin D3 Supplements

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By Thomas Youngerman

Reviewed by Juliana Tamayo, MS, RDN - Last Updated

Best Vitamin D3 Supplements

Forty-two percent of American adults are Vitamin D deficient. If you have concerns, you may be among them; this article is a must-read. We have prepared a review of Vitamin D, what it is, where it comes from, and a discussion of deficiency. We’ll then discuss vitamin D3, its supplementation, its benefits, recommended dosages, and if D3 supplementation is right for you. Finally, we’ll give you our unbiased recommendation of several stellar Vitamin D3 products from some of the most respected brands in the natural products’ space and illustrate how you might stack D3 with calcium for even better results.

Vitamin D is an essential nutrient your body requires primarily to build strong bones and for overall good health. A fat-soluble vitamin that functions like a steroid hormone in the body, vitamin D comes in two forms – D2 and D3. D3 can also be produced in your skin when exposed to sunlight. So, what are the best vitamin D3 supplements?

Vitamin D3

Vitamin D – The Sunshine Vitamin

Vitamin D is a fat-soluble vitamin that promotes the absorption of calcium, magnesium, and phosphorus, regulates bone growth, and plays a vital role in immune function. It is often referred to as the “sunshine vitamin” as your body produces Vitamin D naturally when exposed to sunlight. You can also access Vitamin D through diet and supplements to ensure adequate levels in your blood.

In addition to healthy growth and the development of bones and teeth, D is believed to play a role in resisting certain diseases. Studies show that those who are D deficient are at higher risk of heart disease, prostate cancer, dementia, and schizophrenia, in addition to the more frequently cited soft or fragile bones (osteoporosis). D is also responsible for modulating cell growth, neuromuscular and immune function, and the reduction of chronic inflammation.

There is newly published research out of the University of Southampton England, stating there is “an indisputable relationship between vitamin D and the immune system.” Avoiding a vitamin D deficiency provides clear benefits for immune health.

Vitamin D is a family of nutrients; D1, D2, and D3, that share similarities in chemical structure. Usually, when we refer to Vitamin D, we are speaking of one of the two primary forms Vitamin D2 (ergocalciferol) or Vitamin D3 (cholecalciferol), collectively known as calciferol. Research suggests that vitamin D3 is more effective than vitamin D2 at raising blood levels of vitamin D.Vitamin D3 from Sunlight

Vitamin D3 Comes From Animals, Vitamin D2 From Plants

These two forms of Vitamin D differ depending on their food sources. Vitamin D3 is only found in animal-sourced foods, whereas D2 mainly comes from plant sources and fortified foods.

Sources of Vitamin D3 include oily fishes and fish oils, liver, egg yolk, butter, and dietary supplements. Whereas Vitamin D2 is sourced from mushrooms, foods fortified with D by manufacturers, and again, nutritional supplements.

And, as we’ve discussed, your skin also produces vitamin D3 when it’s exposed to sunlight – UVB rays trigger the manufacture of D3 from the compound 7-dehydrocholesterol in your skin.

What Is Vitamin D Deficiency?

In 2014, the U.S. Preventive Services Task Force, a federally funded panel of health experts, said there was no universal agreement on how to define vitamin D deficiency or what level was ideal. However, there are general guidelines, and there are symptoms of D deficiency, including:

  • General tiredness or a sense of generally not feeling well
  • Aches and pains
  • Severe bone or muscle pain and weakness
  • Stress fractures in your legs, pelvis, or hips

Those who live in densely populated metropolitan areas, spend more time indoors, or have dark skin are at risk for lower D levels. Darker skin equates to higher levels of melanin, so less Vitamin D is absorbed when in the sun.

If you are experiencing any of the above symptoms, your doctor can perform a simple blood test to determine Vitamin D deficiency. For those diagnosed with a deficiency, your doctor may suggest X-rays to determine bone strength and will likely recommend you take daily vitamin D supplements. D3 deficient

What Are Vitamin D3 Supplements?

Vitamin D dietary supplements come as either Vitamin D2 or Vitamin D3, usually in a soft gel or liquid delivery. Less than twenty years ago, fewer than one percent of adults used a D supplement, today nearly one in five use Vitamin D every day. The increase is attributable to an expanded awareness of D deficiency, women with osteoporosis, and our aging population. As we age, there is a reduction of Vitamin D production in our skin, resulting in up to a fifty percent decrease in the formation of Vitamin D3.

Vitamin D3 Supplementation

Although we may not know the ideal level of Vitamin D, there are some well-established guidelines. The National Institute of Health recommends adults should consume between 400-800 international units (or 10 to 20 mcg) of vitamin D daily.  Please see the below chart.

Table 2: Recommended Dietary Allowances (RDAs) for Vitamin D [1]
Age Male Female Pregnancy Lactation
0–12 months* 400 IU
(10 mcg)
400 IU
(10 mcg)
1–13 years 600 IU
(15 mcg)
600 IU
(15 mcg)
14–18 years 600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
19–50 years 600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
600 IU
(15 mcg)
51–70 years 600 IU
(15 mcg)
600 IU
(15 mcg)
>70 years 800 IU
(20 mcg)
800 IU
(20 mcg)

* Adequate Intake (AI)

Reprinted from the National Institute of Health

Other experts in the field believe this is far too conservative and suggest supplementing with at least an additional one thousand IU’s. Vitamin D requirements depend on age, race, weight, and sun exposure. Current research indicates that consuming 1,000–4,000 IU (25–100 mcg) of vitamin D daily should be ideal for most people to attain healthy vitamin D blood levels. However, we recommend you don’t consume more than 5,000 IU of vitamin D without your doctor’s permission.

Benefits Of Vitamin D3 Supplements

Since studies indicate those deficient in Vitamin D are at higher risk of heart disease, prostate cancer, dementia, and schizophrenia, some claim supplementation with D3 could protect against those diseases.  More recent research challenges those assumptions and reveals how little is known about this essential nutrient. What we know, for a fact, is that vitamin D helps our bodies absorb calcium for bone health and well-being and reduces chronic inflammation.

Other purported benefits of supplementing with Vitamin D3 are improved cognition and enhanced immune health. Some manufacturers will also attribute reduced risks of cancer, heart disease, diabetes, and multiple sclerosis to their structure-function claims. People deficient in vitamin D3 may also experience increased testosterone levels after supplementation.

Vitamin D3 Forms

Vitamin D supplements are either Vitamin B2 or B3 and come in Soft gel capsule or liquid form. Since D3 is used more effectively in the body, most experts concur that D3 supplementation (cholecalciferol) is recommended over D2 (ergocalciferol).

Vitamin D3 Forms

Alternatives To D3 Supplements

We get Vitamin D from sunlight, nutrition, and supplementation. To prevent deficiency symptoms, the two prevalent alternatives to vitamin D3 supplementation are ample time in the sun and dietary sources. D-rich foods include fatty fish, fish oils, egg yolk, butter, and liver. However, it is difficult to get adequate amounts of Vitamin D3 from diet alone.

Does Vitamin D3 Work?

While low Vitamin D levels have been linked to many health problems, research on supplementation’s effectiveness is inconclusive. Researchers know that vitamin D helps our bodies absorb calcium, which helps keep bones healthy. So, it’s natural to assume that vitamin D supplements may help strengthen our bones and protect against fractures and falls.

Will Vitamin D3 Work for Me?

We suggest that if you meet the criteria for those at a higher risk of being vitamin D3 deficient, you live in a densely populated, metropolitan area, spend more time indoors, or have dark skin, supplementation is a good idea. Or, if you are experiencing any of the symptoms of D3 deficiency, we recommend you see your medical professional, who most likely will prescribe supplementation.

And, if you are a part of the Baby Boomer generation, realize your vitamin D3 levels have declined precipitously, and supplementing is a necessity.

Best Vitamin D3 Supplements

When picking the best Vitamin D3 supplements, we adhered to the following criteria:

  • We ensured the products are manufactured in a certified cGMP facility (Good Manufacturing Practices)
  • We looked for companies and brands that have independent third-party testing for quality-assurance
  • We recommended products that use the appropriate 100% natural D3 form
  • We believe the appropriate dosage is 5,000 IU and our selections reflect that attitude
  • Price/Value – we feel a quality Vitamin D3 supplement should never cost more than $15 per month’s supply

Nordic Naturals D3 Capsules

Nordic Naturals D3 Capsules 5000iu

The winner of Clean Eating magazine’s Clean Choice Award. This 125 mcg (5000 IU) capsule is ideal for adults who don’t get adequate sun exposure. Supports healthy bones, mood, and immune system function. Nordic Naturals D3 comes in an easy-to-swallow, mini soft gel size.

Package contains 120 soft gels, basically a four-month supply, for $23.95 on the Nordic Naturals website.

Solgar Vitamin D3

Solgar Vitamin D3

Solgar has been in the dietary supplement industry for over 70 years as a trusted source for supplements that are free of harmful additives and common allergens. Solgar’s Vitamin D3 5000 IU is perfect for adults that want to supplement a wholesome diet and lifestyle that includes the outdoors.

These soft gels are free of gluten, wheat, dairy, soy, yeast, sugar, sodium, and artificial flavors, sweeteners, preservatives, and colors.

Two hundred and forty capsules per container, $26.99 on Amazon.com.

Country Life Vitamin D3

Country Life Vitamin D3

If you’re searching for a great, gluten-free Vitamin D3 supplement, Country Life Vitamin D3 is one of our top picks. This Certified Gluten-Free supplement is also free of yeast, corn, wheat, soy, milk, salt, sugar, preservatives, and artificial ingredients. Each Non-GMO soft gel contains 5000 IU of vitamin D3 from lanolin.

Two hundred soft gels retail for $17.99 on Amazon.com.

Stacking D3 With Other Supplements

Many people stack D3 with other vitamins or minerals, depending on their situation. During flu season, an excellent stack is to combine D3 with Vitamin C and Zinc. This combination is known to boost immunity against respiratory infections.

Another way to stack D3 is with calcium. Here is a blended approach:

Caltrate, Vitamin D, And Calcium

Caltrate Vitamin D and Calcium

Calcium and vitamin D both support bone health. Combining the two ingredients in one tablet seems a sound strategy. Beyond bone support, this combination may also help promote healthy nerves, hormones, and teeth.

Two hundred tablets of this Caltrate Calcium and Vitamin D3 supplement costs $15.67 on Amazon.

To Summarize

Vitamin D3 represents one of the best values in the dietary nutrition space. The soft gel form is convenient, and the pills are small and easy to swallow. If you meet the criteria for those at higher risk, exhibit any D deficiency symptoms, or are over the age of sixty, we think vitamin D3 is one supplement that should be in your arsenal. Now that you know the best vitamin D3 supplements, pick the one that’s right for you!

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Thomas Youngerman

Thomas Youngerman is an entrepreneur and author in the health and wellness space with extensive experience in the supplement industry. He has owned multiple sports nutrition stores and served as the Category Manager and Director of Business Development for a regional chain of nutrition stores. Thomas created a successful line of men’s healthy aging supplements that was distributed in GNC, The Vitamin Shoppe, and Kroger, and later sold to a West Coast corporation. Thomas was previously a certified nutrition coach. He has a strong understanding of nutrition, supplement formulations, DSHEA, cGMP, and FDA regulations.