The 9 Best Vitamin D Supplements, According to a Dietitian

Vitamin D deficiency can be common—here's what to consider for a supplement.

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The 9 Best Vitamin D Supplements, According to a Dietitian

Verywell Health / Kristin Kempa

Vitamin D is an essential fat-soluble vitamin that plays an important role in bone health, immune health, muscle function, hormones, and carbohydrate metabolism. It may also play a role in depression, though more research is needed. Vitamin D deficiency has been linked to a number of health concerns including type 2 diabetes, certain cancers, and autoimmune diseases, though more research is needed to understand the relationship. 

Sun exposure is the main source of vitamin D for most people. However, time of year, time of day, your age, and the color of your skin all affect how much vitamin D you’re able to produce from sun exposure. In most parts of the U.S. it is not possible to get enough sun exposure during the fall, winter, and early spring months to produce adequate levels of vitamin D. It’s estimated that at least 30% of the U.S population is vitamin D deficient, and many more are considered vitamin D insufficient (blood vitamin D levels < 30nmol/L).

Vitamin D is available in some foods such as fortified milk, sockeye salmon, mushrooms, and soy products, as well as from supplements. Supplements are helpful to increase blood levels of vitamin D and are often recommended to both correct deficiency as well as to maintain adequate levels throughout the winter months.  “No matter what time of year, older adults, people with darker skin, and anyone who has difficulty absorbing fat could benefit from a vitamin D supplement because of decreased production from sunlight or a limited ability to absorb the vitamin,” says Kelsey Kunik, RDN, nutrition advisor at Fin vs Fin.

When choosing a vitamin D supplement, you’ll want to look for D3, which is the most absorbable form. Along with the D3 form, we considered dose and third-party or in-house testing for potency and purity for our top vitamin D recommendations.

Editor's Note

Our team of registered dietitians reviews and evaluates every single supplement we recommend according to our dietary supplement methodology. From there, a registered dietitian on our Medical Expert Board reviews each article for scientific accuracy.

Always speak with a healthcare professional before adding a supplement to your routine, to ensure that the supplement is appropriate for your individual needs and which dosage to take.

Best Overall

Theralogix Thera-D 2,000

Theralogix Thera-D 2,000


  • NSF Contents Certified 

  • Vegetarian, certified gluten-free

  • Small and easy to swallow

  • Inexpensive

  • May be higher dose than some people need

  • May interact with certain medications

Theralogix Thera-D 2,000 IU tops our list because of its simple ingredients, easy to swallow capsule, and third-party certification by NSF—one of our most trusted third-party testing organizations. It's also one of our most budget-friendly picks for a vitamin D supplement. Each tablet contains 2,000 IU (50 micrograms) of vitamin D3. Research shows this amount may be needed to maintain adequate vitamin D levels, especially among older adults who are at higher risk for deficiency. For example, The Endocrine Society notes that in order to maintain blood levels >30 nmol/L, most people may need to supplement with 1,500 to 2,000 IU per day.

However, this is significantly higher than the recommended daily allowance of 600 IU and may be more than some people need—especially younger people that are able to produce some vitamin D from sun exposure.

The small tablet is gluten-free, vegetarian, and die-free. It does contain a very small amount of calcium, which is safe for most people, and may further support bone health. Calcium supplements may interact with some medications including certain antibiotics, so it’s recommended you take them separately from medication and always check with your healthcare provider to ensure they are safe for you.

Price at time of publication: $28 ($0.16 per serving)

Key Specs:
Tablet | Type: D3 | Dose: 2,000 IU (50 mcg) | Third-Party Certified: Yes | Servings Per Container: 180 

Best Moderate Dose

Now FoodsD-3, 1000IU

Now FoodsD-3, 1000IU


  • Gluten-free and vegan 

  • Tested for potency and purity 

  • Free of common food allergens

  • Dose may be too low to correct deficiency

Now Foods D-3, 1,000 IU is a good choice for those looking for a more moderate dose of vitamin D. Now Foods is known for their quality supplements at an affordable price, and their D-3 supplement is no exception. The company does extensive in-house testing for purity and potency, ensuring that what’s on the label is actually what’s in the bottle, and that there aren’t any harmful contaminants like heavy metals. This supplement is also free of common allergens, and is gluten-free and vegan. 

The dose of 1,000 IU exceeds the current RDA for adults of 600 IU, although it’s been called into question whether the RDA recommendation is high enough. The exact amount needed to raise blood levels to 30 nmol/L (considered sufficient), may depend on age, body fat, and current blood levels. So, 1,000 IU may be an adequate dose for some but not enough for others. Ultimately, it’s best to work with your healthcare provider to monitor your current levels and amount needed in a supplement. 

Price at time of publication: $7 ($0.19 per serving)

Key Specs:
Softgel | Type: D3 | Dose: 1,000 IU (25 mcg) | Third-Party Certified: No | Servings Per Container: 360

Best Multivitamin

Thorne Research Basic Nutrients 2/Day

Thorne Research Basic Nutrients 2/Day


  • NSF Certified for Sport

  • Research backed dose of vitamin D for maintenance

  • Contains other nutrients to support bone health

  • Gluten-free

  • Some nutrients may interact with certain medications

If you’re looking to supplement vitamin D as part of a multivitamin, we recommend Thorne Basic Nutrients 2/day. This choice tops our list for a multivitamin with vitamin D because it’s NSF Certified for Sport and contains active forms of most nutrients including D3, which is better absorbed by the body. In addition to 2,000 IU (50 micrograms) of vitamin D, it has other nutrients involved in bone health. For example, it contains vitamin K, which works with vitamin D to support bone density. It also contains 2 milligrams of boron, which may further support bone health.

If you take any other supplements or medications, it’s essential to work with a healthcare provider to make sure that you aren’t exceeding tolerable upper limits of any nutrients and that this multivitamin doesn’t interact with any medications you’re currently taking. 

Price at time of publication: $36 ($0.60 per serving)

Key Specs:
Capsule | Type: D3 | Dose: 2,000 IU (50 mcg) | Third-Party Certified: Yes | Servings Per Container: 60

Best Gummy

Nordic Naturals Vitamin D3 Gummies Sport

Nordic Naturals Vitamin D3 Gummies Sport


  • NSF Certified for Sport

  • Lower in added sugar

  • Free of gluten and dairy

  • No artificial colors or flavors

  • Dose may be too low to correct deficiency

If you prefer a chewable option, we recommend Nordic Naturals Vitamin D3 Sport Gummies. Each gummy has 1,000 IU of vitamin D3 and only has two grams of sugar—relatively low for a gummy vitamin. They’re also gluten-free, Non-GMO verified, and vegetarian. We also like that the color comes from fruit and vegetable juice instead of artificial sources.

Importantly, Nordic Naturals Vitamin D3 Sport Gummies are NSF Certified for Sport, a rigorous third-party certification that tests for purity, potency, and any substances banned by sport. Third-party testing is important for all supplements but especially for gummies. For example, has discovered gummies are more likely than other forms of supplements to contain unreliable amounts of supplement ingredient amounts.

As noted, the 1,000 IU level of D3 may be enough for some to correct a deficiency, but some may need a higher dose.

Price at time of publication: $20 ($0.33 per serving)

Key Specs:
Gummy | Type: D3 | Dose: 1,000 IU (25 mcg) | Third-Party Certified: Yes | Servings Per Container: 60

Best Prenatal

FullWell Prenatal Multivitamin

FullWell Prenatal Multivitamin


  • Third-party tested for potency and purity

  • Formulated by a dietitian

  • Active form of all nutrients to support pregnancy

  • Eight capsule serving size

  • Expensive

Vitamin D is an essential nutrient for pregnancy, not only to maintain the pregnant woman’s stores but also to support the baby's growing bones. Low vitamin D status in late pregnancy has also been linked to higher risk of preterm birth. Low vitamin D in pregnancy has also been shown to play a role in gestational diabetes and preeclampsia, but more research is needed.

Our top pick for a prenatal with vitamin D is Full Well’s prenatal because it has 4,000 IU of vitamin D3—667% of the Daily Value. The current recommendation for vitamin D during pregnancy is 600 IU; however, newer research suggests that may be far too low for many women. One review of several randomized control trials found that 4,000 IU was not only effective at achieving optimal levels for pregnancy but was also safe. Pregnant people are encouraged to discuss supplement use with their healthcare provider before starting a high dose of vitamin D.

We also like this prenatal contains vitamin K, which works alongside vitamin D to support bone health. We appreciate all nutrients in this prenatal are in the most absorbable form. In addition, Fullwell’s prenatal is a top choice of ours for their commitment to purity, potency, and transparency. They test both ingredients and the final product with extensive third-party testing. 

Because it’s such a comprehensive supplement, one dose is eight capsules, which can be a lot for pregnant people to take. The company recommends splitting it into two doses of four capsules twice per day to make it easier to get all eight capsules in.

Price at time of publication: $50 ($1.67 per serving)

Key Specs:
Capsule | Type: D3 | Dose: 4,000 IU (100 mcg) | Third-Party Certified: Yes | Servings Per Container: 30

Best Vegan

HUM Here Comes the Sun Vitamin D3 Immune System Support Supplement

HUM Here Comes the Sun Vitamin D3 Immune System Support Supplement


  • Third-party tested for potency and purity

  • Free of gluten and common food allergens

  • Dose may be higher than some people need

For those that follow a vegan diet, HUM Nutrition Here Comes the Sun is a good choice for vitamin D. Each vegan capsule contains 2,000 IU of vitamin D3 and has been third-party tested for purity and potency. While 2,000 IU is higher than the RDA (600 IU), it’s well below the tolerable upper intake level (4,000 IU), and higher amounts may be helpful in achieving optimal vitamin D status for many people. However, alway check with your healthcare provider to determine if this dose is appropriate for you. 

The softgels, which contain olive oil, glycerin, tapioca and water, are also gluten-free, and free from all major allergens. 

Price at time of publication: $12 ($0.40 per serving)

Key Specs:
Softgel | Type: D3 | Dose: 2,000 IU (50 mcg) | Third-Party Certified: Yes | Servings Per Container: 30

Best For Kids

D Drops Booster Liquid Vitamin D

D Drops Booster Liquid Vitamin D


  • NSF Contents Certified

  • No added sugar

  • Can easily be added to food or drinks

  • Only one drop needed

  • Bottle doesn’t always dispense drops easily

When choosing a supplement for kids, something easy to eat or drink is a top priority for most parents. This is why we love D Drops Booster Liquid Vitamin D. Just one small drop provides 600 IU of vitamin D, which is 100 percent of the RDA for kids over the age of one. It can be added to any food or drink, making it super easy for kids to consume. The only drawback is that the dispenser doesn’t always dispense drops easily or evenly, so you may have to tap the bottle slightly to get it to come out. 

We also appreciate that D Drops don’t contain any added sugar or alternative sweeteners (they’re essentially flavorless) and are NSF Contents Certified. So, you can rest assured that you’re giving your little one just what’s on the label and nothing more.

Price at time of publication: $10 ($0.10 per serving)

Key Specs:
Liquid | Type: D3 | Dose: 600 IU (15 mcg) | Third-Party Certified: Yes | Servings Per Container: 100

Best Liquid

Source Naturals Vitamin D-3 Liquid Drops

Source Naturals Vitamin D-3 Liquid Drops 2000 iu Supports Bone &amp; Immune Health - 4 Fluid oz


  • Adjustable dose

  • Third-party tested for purity and potency

  • No added sugar

  • Budget-friendly

  • Large number of drops per serving

For those that prefer a liquid vitamin, we recommend Source Naturals Vitamin D3 Liquid. It’s been third-party tested, doesn’t contain any added sugar, and it’s budget-friendly. 

One serving, which is nine drops, provides 2,000 IU of vitamin D3, which is at the top end of the dose recommended by the Endocrine Society for anyone who is deficient. However, if you need more or less, you can easily adjust the dose by taking more or fewer drops. The flavorless liquid can be added to any drink, which makes it easy to take. 

Price at time of publication: $15 ($0.02 per serving)

Key Specs:
Liquid | Type: D3 | Dose: 2,000 IU (50 mcg) | Third-Party Certified: Yes | Servings Per Container: 695

Best High Dose

Momentous Vitamin D

Momentous Vitamin D

Live Momentous 

  • NSF Certified for Sport and Informed Sport Certified

  • Research backed dose for correcting deficiency

  • High dose may not be best for those without deficiency

Momentous Vitamin D is NSF Certified for Sport and Informed Sport Certified meaning it has strong third-party testing for ingredient accuracy and free of contaminants. We also like it contains a research-supported level of vitamin D for correcting a deficiency. The Endocrine Society suggests anyone who is deficient in vitamin D (<20 nmol/L) take a high dose of vitamin D for eight weeks to bring levels to the sufficient range, and then you can continue on with a maintenance dose of 2,000 IU or less.

Because vitamin D is fat soluble, and excessive vitamin D can lead to hypercalcemia (too much calcium), most people should not take high doses of vitamin D for the long term. Always check with your healthcare provider to ensure this dose is safe for you, and how long you should take a high dose.

Price at time of publication: $16 ($0.27 per serving)

Key Specs:
Capsule | Type: D3 | Dose: 5,000 IU (125 mcg) | Third-Party Certified: Yes | Servings Per Container: 60

Are Vitamin D Supplements Beneficial? 

Vitamin D supplements are an effective way to help many people increase and maintain adequate levels of vitamin D. Because food sources of vitamin D are limited, and—in many parts of the world—it’s not possible to make adequate vitamin D in your body from sun exposure, a large majority of the population can benefit from vitamin D supplements. If you have a known deficiency, supplements are beneficial. 

However, the following groups of people may find them especially helpful: 

  • Older adults. Older adults are at higher risk for vitamin D deficiency because the ability of skin to synthesize vitamin D declines as we age. They may also spend less time outdoors.
  • People with darker skin. Skin with more pigment (color) produces less vitamin D than lighter skin. People of African American descent are known to be at higher risk of vitamin D deficiency than those with white skin.
  • People who have difficulty absorbing fat. If you have a medical condition that lessens your ability to absorb fat such as liver disease, crohn’s disease, ulcerative colitis, and cystic fibrosis, or have had your gallbladder removed, you may be at higher risk for deficiency.
  • People who have had bariatric surgery. Bariatric surgery reduces your ability to absorb all nutrients, including vitamin D. In addition, it’s been shown that fat cells can hold onto vitamin D and not release it into the bloodstream effectively, leading to deficiency. The Endocrine Society recommends a dose of 3,000 IU or more daily for anyone who has had bariatric surgery.
  • People who have a high body fat percentage. People in larger bodies, particularly those with high fat mass, are at higher risk for vitamin D deficiency because fat cells may not efficiently release vitamin D into the bloodstream.
  • Pregnant people. Vitamin D plays an essential role in the skeletal development of a baby, and may play a role in other pregnancy outcomes. It’s essential that pregnant people maintain adequate levels of vitamin D.
  • People trying to conceive. Research suggests that adequate vitamin D levels may play a role in fertility, and vitamin D deficiency or insufficiency may lower your chance of conceiving.
  • Post menopausal women. Post menopausal women are at higher risk for osteoporosis, and getting adequate vitamin D can help maintain bone density.
  • People with osteoporosis. It’s recommended that people with osteoporosis take 800 IU of vitamin D daily to support bone density and reduce risk of fractures.
  • People with PCOS. It’s estimated that up to 85 percent of people with PCOS are vitamin D deficient. A supplement may help with symptoms and risk of other conditions.
  • Breastfed babies. Breast milk contains very little vitamin D, and babies who are exclusively breastfed should take a supplement. Some research indicates that when breastfeeding mothers take high doses (6,400 IU) of vitamin D, there may be adequate levels of vitamin D in breastmilk. Speak with your healthcare provider to determine the best approach for you and your baby. 
  • People with chronic kidney disease or liver disease. These illnesses can affect your body’s ability to convert vitamin D into a usable form.

Who May Not Benefit From Vitamin D Supplements 

Vitamin D supplements are considered safe for most people. However, the following people may not benefit from a supplement, or the risks may outweigh the benefits. 

  • People with adequate vitamin D levels. If you are able to maintain blood vitamin D levels of 30nmol/L throughout the year via food and sunshine, there is little to no benefit to supplements. And excessive vitamin D may lead to harmful side effects. 
  • People with high blood calcium levels. Caroline Thomason, RD, CDCES advises those with high blood calcium to talk with their doctors before they take a Vitamin D supplement. This is because vitamin D enhances calcium absorption, which can lead to excessive calcium, explains Sharon Puello MA, RD, CDN, CDCES.
  • People prone to kidney stones. Vitamin D supplements may elevate risk for kidney stones because they increase absorption of calcium. More research is needed to clarify the relationship between vitamin D supplements and kidney stones, so talk with your healthcare provider about the risks and benefits of supplements for you.
  • People taking certain medications. Vitamin D supplements may interact with some medications including diuretics, statins, and steroids. Always speak with your healthcare provider to determine if supplements are recommended for you.

How We Select Supplements 

Our team works hard to be transparent about why we recommend certain supplements; you can read more about our dietary supplement methodology here

We support supplements that are evidence-based and rooted in science. We value certain product attributes that we find to be associated with the highest quality products. We prioritize products that are third-party tested and certified by one of three independent, third-party certifiers: USP, NSF, or 

It's important to note that the FDA does not review dietary supplements for safety and effectiveness before they go to market. Our team of experts has created a detailed, science-backed methodology to choose the supplements we recommend.

Other health experts we interviewed for insight on choosing the best vitamin D supplement include:

  • Kelsey Kunik, RDN, dietitian, nutrition advisor at Fin vs Fin, and sustainable food blogger
  • Caroline Thomason, RD, CDCES, dietitian and diabetes educator
  • Sharon Puello, MA, RD, CDN, CDCES, dietitian and diabetes educator

What to Look For in Vitamin D Supplements

Third-Party Testing

Supplements that are third-party tested are sent to a lab where they are tested to ensure they contain what they say they contain and are not contaminated with specific high-risk, common contaminants. However, it’s important to note:

  • Third-party testing does not test to see if a product is effective or safe for everyone, and it does not ensure the supplement will not interact with other supplements or medications.
  • Not all third-party testing is created equal. It is not uncommon for supplement companies to pay labs for certificates after conducting minimal to no testing. 
  • The third-party certifications we can trust are, NSF, and USP. However, these certifications are difficult to obtain and/or expensive for manufacturers, so many companies choose not to get their products tested by one of these three organizations. 
  • Sometimes products tested by these three companies are more expensive to try to offset the cost they pay for certification.
  • Just because a supplement is not tested by one of these three companies, it does not mean it’s a bad product. We recommend doing some research on the reputability of the manufacturer and calling up the manufacturer and their testing lab to determine their protocols and decide if you feel comfortable consuming the supplement.


In supplements, vitamin D comes in two forms: D2 (ergocalciferol) and D3 (cholecalciferol). Both can raise blood levels of vitamin D, but D3, which is what your body makes from sunlight, is better absorbed by the body. That’s why all our recommended supplements are in the D3 form.

Vitamin D supplements are available as capsules, tablets, softgels, gummies, and liquid. The best form is the one that you will take consistently. 

Ingredients & Potential Interactions

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included, relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you are taking.

Vitamin D may be paired with other nutrients for bone health or heart health including calcium, vitamin K, magnesium, and more. It is also found in multivitamins including prenatal vitamins, which contain a variety of vitamins and minerals. Each of these nutrients may interact with medications or other supplements, so always check with your healthcare provider to see if a combination supplement is safe for you.


The recommended dietary allowance (RDA) is 600 IU for kids over the age of one and adults under the age of 70 (it jumps to 800 IU for 70 year olds and older). However, recent research suggests that may not be enough to correct a deficiency, or may not even be enough for some people to maintain adequate vitamin D levels. 

One analysis suggests that you may need up to 5,000 IU per day to correct a deficiency, and then at least 2,000 IU per day to maintain adequate blood levels once sufficient levels have been achieved. The Endocrine Society echoes this information in their recommendations. More research is needed in this area, and the exact amount you need will depend on your lifestyle, skin type, age, sun exposure, and current status. 

Work with your healthcare professional to determine the best dose for you.

How Much is Too Much?

Vitamin D is a fat soluble vitamin, meaning your body stores any vitamin D not currently in use. Excess vitamin D can be toxic, so over supplementing is a health concern. The effects are long term and include hypercalcemia (too much calcium absorption), which can lead to kidney failure. Excessively high blood levels of vitamin D have also been linked to increased risk of cardiovascular disease and certain cancers.

The tolerable upper intake level (UL) is 4,000 IU per day, though it’s noted that toxicity is rarely seen at levels lower than 10,000 IU per day. Studies with doses of 5,000 IU per day given temporarily to correct a deficiency suggest that it is safe in the short-term.

If you’re taking a higher dose of vitamin D, it’s essential to work with your healthcare provider to monitor your blood levels and ensure you’re not taking too much.

Frequently Asked Questions

  • How do I know if I am deficient in Vitamin D?

    Signs of deficiency may include bone pain, fatigue, muscle twitching, and weakness. However many people do not experience symptoms and are deficient. Your healthcare provider can check your vitamin D levels with a simple blood test. A blood level lower than 30 nMOL/L is considered deficient.

  • How much sun would I need to have enough Vitamin D without a supplement?

    The amount of sun exposure you need varies by individual and where you live. It’s important to note, that in much of the world, it is nearly impossible to get adequate sun exposure for vitamin D production during late fall, winter, and early spring.

    “During the spring and summer months, you may only need 10-15 minutes of sun exposure while wearing a short-sleeved shirt to produce 1,000 IU of vitamin D, which researchers believe is enough to help support skeletal health in most people,” says Kunik. The time of day matters, too. In the earlier and later parts of the day when the sun is lower in the sky, you may need more time in the sun to get adequate levels.  

    Your individual skin tone plays a role in how much sun you need as well. Those with lighter skin need less time in, while those with darker skin tones, may need hours of sun exposure to produce a significant amount of vitamin D, explains Puello. 

    There is a theory that sunscreen may block the ability of your skin to produce vitamin D from sunlight. Research doesn’t support this, but more research is needed, especially larger trials using higher SPF levels. That said, the risk of skin cancer and damage to your skin still outweighs concerns about vitamin D levels.

  • What are side effects of vitamin D supplements?

    Side effects of vitamin D supplements are typically seen with very high doses (regular intake greater than 4,000 IU per day), or for those that have high serum levels, and don’t need a supplement. Too much vitamin D can lead to hypercalcemia, which can lead to nausea, vomiting, muscle weakness, neuropsychiatric disturbances, pain, loss of appetite, dehydration, polyuria, excessive thirst, and kidney stones.

  • What is the difference between vitamin D, D2 and D3?

    D2 and D3 are two different forms of vitamin D. “Vitamin D3 is the most bioavailable form which means that the body is able to more readily use it,” says Thomason.

     Vitamin D2 is a synthetic form and your body needs to convert it to a form that it can use. Because of this, it’s recommended that you take D3 in supplement form. However, prescription vitamin D, which is given at much higher doses, is usually vitamin D2 (ergocalciferol).

  • How much vitamin D should I take?

    The amount of vitamin D you need is highly individualized. Start by having your blood levels checked by your healthcare provider and work with them to determine the best dose for you for the best results.

Why Trust Verywell Health

Sarah Anzlovar, MS, RDN, LDN, is a registered dietitian with her master's degree in nutrition communication from the Tufts Friedman School of Nutrition Science and Policy. She owns a private practice in the suburbs of Boston, where she helps her clients ditch diets and learn to eat foods that help them feel their best and achieve optimal health. Sarah is also a freelance writer, where she lends her expertise in translating the research on a wide variety of nutrition topics into relatable and approachable recommendations for consumers.

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