Vitamin D is a critical nutrient for both physical and mental health. Functions as diverse as your immune system, bone strength, athletic performance, and your cognitive capabilities are all damaged by low levels of vitamin D. Worse, vitamin D deficiency is very common among people who don’t live near the equator.
Vitamin D is known for helping the body absorb calcium, but it does far more than that—in fact its functions are so widespread that, if it were discovered today, it would probably be categorized as a hormone, not as a vitamin. Because of the wide prevalence of vitamin D deficiency, taking a vitamin D supplement is a very smart call.
Here, we’ve ranked the top vitamin D supplements on the market. After the rankings, we’ll break down how vitamin D works and how it can benefit you.
1. Essential Elements D3
Essential Elements gives us the best vitamin D3 supplement on the market. Not only does it contain a generous dose of vitamin D3 (as Cholecalciferol) – that helps to boost bone health, testosterone and heart health – it encapsulates the entire product in heart-healthy organic avocado oil for better absorption and bioavailability.
Essential Elements D3 is completely free of common allergens and contains zero fillers, dyes, additives or preservatives. Every bottle comes packed with a 1 year supply, making it the purest and most convenient vitamin D supplement on the market.
Alpha XR’s #1 choice.
2. TransparentLabs RawSeries Vitamin D3
RawSeries Vitamin D3 delivers 5,000 IU of active vitamin D. No artificial sweeteners. No artificial coloring. Gluten-free and non-GMO. No artificial preservatives.
Each capsule packs your daily vitamin D in a gelatin softgel (vegans be aware) with safflower, glycerin, water, and sunflower oil. The plant-based oil carriers ensure you’ll get full absorption. And with 120 capsules in each bottle, you’re good for a full 3 months.
3. Solar Essence Vitamin D3 + K2
Nuzena’s formula offers a healthy dosage of Vitamin D3, while their formula also includes vitamin K2, calcium and bioperine.
One thing we are pleased to see is the inclusion of Bioperine, a natural stimulant that aids the absorption of nutrients and benefits the body’s metabolism.
We were impressed by Nuzena, who offer a wide range of products that cater for all dietary needs. Providing natural formulas, which are non-GMO, gluten free, vegan-friendly and also produced in FDA registered facilities ensuring quality certification.
Solar Essence Vitamin D3 by Nuzena takes a solid top-3 spot for the best Vitamin D3 supplement.
4. Nordic Naturals Vitamin D3
Although Nordic Naturals is more famous for their fish oil products, they’ve branched out to vitamin D as well. It makes perfect sense, considering that vitamin D is rather scarce in Scandinavia.
Nordic Naturals D3 provides a concentrated vitamin D source alongside some of its trademark healthy oils. Each softgel provides 5000 IU of vitamin D3, dissolved in olive oil and the omega-9 fatty acid oleic acid. The softgels are flavored with natural orange extract and preserved with rosemary extract, which removes the need for a synthetic preservative to keep the supplement fresh.
5. Sports Research Vegan D3
Sports Research Vegan D3 is one of the few vitamin D supplements on the market that’s derived from plant sources. As you might guess, the capsule is made from plant cellulose. If plant sources are important to you, this should be your supplement of choice.
6. Carlson Labs D3
Carlson Labs delivers a pretty simple supplement, using safflower and corn oil to dissolve the fat-soluble vitamin D3 it contains in a gelatin-based capsule that delivers a moderate dose of 2000 IU of the vitamin.
Only the most persnickety buyer could fault Carlson Labs for using a less healthy option than olive oil. The only reason oil is present in the first place is because vitamin D3 is not soluble in water; it must be dissolved in fat instead.
7. Nutrigold Vitamin D3
Nutrigold has a strong tradition of quality ingredients for a low cost with a purist, minimalist design philosophy, and that holds true here, too. One attractive perk that speaks to Nutrigold’s commitment to purity is that, unlike some of its competitors, this supplement is not manufactured on equipment shared with allergens like soy, milk, wheat, or fish. If you have allergies to any of these ingredients, getting Nutrigold Vitamin D3 is a good call.
8. NatureWise Vitamin D3
As the number one best-seller on Alpha XR, NatureWise Vitamin D3 has some serious clout. It’s also a very serious supplement-it delivers 5000 IU of the vitamin per capsule.
This is a lot higher than the recommended daily intake (600 IU, updated from 400 IU in 2010). Still, many scientists and nutritionists advocate for much higher values, noting that exposure to direct sunlight can elicit the same blood vitamin D response as several thousand IUs per day.
If you are a believer in a higher daily intake of vitamin D, which might be a good idea for residents of northern climates in the wintertime, and especially so for those residents with darker skin, this is a great choice.
This product appeals to the minimalist, too, as the only ingredients aside from vitamin d are olive oil and the constituents of the capsule (gelatin and glycerin).
All but serious avoiders of animal products can be encouraged to see this ingredient list.
Since each bottle provides 360 capsules, and each capsule contains 5000 IU of vitamin D, it’s among the best in terms of value: the amount of vitamin D you’ll get per dollar is tremendously high.
9. Doctor’s Best Vitamin D3
The Doctor’s Best brand has a reputation for high-quality supplements with low cost and good purity. Its vitamin D offering lives up to this standard fairly well.
It comes in two different dosages, 2000 IU and 5000 IU. These give you flexibility when it comes to dosing, both from person to person (a large man needs more vitamin D than a slim woman) and throughout different times of the year.
You may want to do a lower dosage in the summer and a higher dose in the winter, for example.
It should come as no surprise that the only other ingredients are virgin olive oil, gelatin, and water. One downside to Doctor’s Best Vitamin D3 is that no independent lab testing is available to assay its purity, so you’ll have to rely on the overall reliability of the brand based on its other offerings.
Fortunately, Doctor’s Best has one of the best track records among the widely distributed low-cost brands, so odds are the dosing is accurate and there are no impurities present.
10. Now Foods Vitamin D3
As one of the mainstays of inexpensive and simple vitamins, Now Foods brand is a common sighting at local big-box retailers and pharmacies.
It’s a very simple supplement; each softgel contains 1000 IU of vitamin D dissolved in olive oil and delivered in a gelatin capsule.
Problems start to arise when we look at how Now Foods Vitamin D3 fares on independent lab testing of its contents.
Analytical tests show that the supplement actually contains 30% more vitamin D than its label states: each softgel actually delivers 1300 IU of vitamin D.
While this might sound like a good deal from a value perspective, it is not exactly a ringing endorsement of the quality control capacities at Now Foods.
This is a problem its other supplements have struggled with, too. Sometimes it’s worth it for a cheap supplement with no extra ingredients.
You’ll have to decide what’s important to you; if you want precision, look elsewhere, but Now Foods Vitamin D3 is not a bad deal as far as cost per serving of vitamin D goes.
11. Thorne Research Vitamin D-1000
On the surface, Thorne Research Vitamin D-1000 looks pretty standard. It’s a vegetarian cellulose-based vitamin D supplement that delivers 1000 IU per day.
However, it’s got one interesting and unusual ingredient: the amino acid leucine.
The choice of this particular amino acid might seem a bit puzzling at first, but Thorne Research might be ahead of the curve: a 2015 study on elderly patients found that adding leucine (as well as whey protein) to the vitamin D supplementation regimen of people at risk for sarcopenia–the loss of muscle mass associated with aging–found that leucine helped prevent this muscle loss (1).
It’s not clear how or why this works, but it might be a good idea to go for Thorne Research’s vitamin D offering if you are getting older and want to think about your muscle mass retention.
Best vitamin D overall: Essential Elements D3
With its super-clean supplement design, heart-healthy avocado oil, and potent 5000 IU dosage, Essential Elements D3 is a clear all-around best.
Best vitamin D for the winter: Nordic Naturals Vitamin D3
If you only take vitamin D during the winter (because of a lack of sun exposure), you might as well take something that goes down easy. Thanks to natural orange flavor and rosemary, Nordic Naturals D3 doesn’t have an oily aftertaste, making it seamless to integrate into your supplementation routine in the winter.
Best vitamin D for boosting your immune system: Essential Elements D3
Many American adults are deficient in vitamin D, and getting your vitamin D levels back up to the healthy range should be your top priority if you want to boost your immune system. That’s why the high dose of vitamin D3 provided by Essential Elements D3 is the best pick for boosting immunity.
Best vitamin D for depression: Transparent Labs Vitamin D3
Vitamin D-based treatments for depression rely on high doses of very pure supplements, making Transparent Labs’ ultra-clean supplement design an ideal choice.
Best vitamin D for older adults: Solar Essence D3 + K2
Solar Essence delivers a solid 5000 IUs of vitamin D3, and in addition, it delivers 80% of your vitamin K2 needs for the day, which is a micronutrient that’s often lacking in older adults, making it an easy winner in this category.
Best vitamin D for vegetarians and vegans: Sports Research Vegan D3
Finding true vegan vitamin D3 is tough, but Sports Research has managed to come up with a powerful vitamin D3 supplement that is coconut-oil based. It’s definitely the best choice if you want to avoid animal ingredients in your vitamin D3 supplement.
Who should buy vitamin D?
Nearly everyone who doesn’t live in the tropics should consider taking a vitamin D supplement at least some of the year.
The critical role of vitamin D in health, combined with the high prevalence of clinical and subclinical vitamin D deficiency across many parts of the world, should be evidence enough to seriously consider taking a vitamin D supplement.
Since the human body cannot synthesize vitamin D naturally without exposure to sunlight, if your skin doesn’t see the sun much, you are very likely to develop vitamin D deficiency.
People at risk for vitamin D deficiency can broadly be divided into three categories. First among these is people who live in northern climates, who have long, dark winters with cold temperatures.
Research shows that the prevalence of low vitamin D levels increases the further you move away from the equator, which makes sense given that you’re not likely to get much sun on your skin when it’s cold out, or when it’s only sunny for six or seven hours out of the day.
Even people who live in warm climates can be prone to vitamin D deficiency if they spend most of their time indoors and cover up with sunscreen when they are outdoors.
The second category of people at risk for vitamin D deficiency is people with darker skin. Having more melanin in your skin helps protect your body against damage from sunlight, but it also makes it harder for your body to synthesize vitamin D.
In fact, vitamin D levels are one hypothesized reason why people whose ancestors lived far from the equator have lighter skin.
In any case, if you have darker skin, and particularly if you have darker skin and you live somewhere with a cold climate, your risk of vitamin D deficiency is particularly high.
The final group that should consider vitamin D supplementation more strongly is older adults. The elderly are at a notably higher risk of vitamin D deficiency, though it’s unclear whether this is merely the result of spending more time indoors than their younger counterparts, or the result of changing hormonal biology as you get older.
Regardless, given the potential associations between low vitamin D levels and a huge range of health problems that afflict the elderly, a vitamin D supplement is a smart idea.
How we ranked
Since vitamin D is such a popular supplement, we started with dozens of potential candidates for our rankings. Our first priority was dosage: each capsule (not each serving) had to offer at least 1000 IUs of vitamin D.
As things currently stand, professional medical association recommendations are 600 IUs per day for adults, and 800 IUs per day for the elderly (1).
Many scientists have called for these recommendations to be increased, as evidence accumulates that higher levels may be necessary for optimal health.
Indeed, many clinical trials on the efficacy of vitamin D use higher than this 800 IU per day threshold. If any vitamin D supplement is considered “best,” it had better contain more than the minimum recommended amount.
Beyond the reported dose on the label, we also referred to independently verified metrics of the actual dosage delivered by the capsules. We dropped any supplements whose reported dose differed wildly from its actual dose, especially if it was delivering less vitamin D than advertised.
We also required that vitamin D supplements deliver their vitamin D in some type of lipid (fat) solution. Vitamin D is fat-soluble, so unlike water-soluble vitamins like vitamin C, its absorption could theoretically be adversely affected if it isn’t already dissolved in some kind of fat.
Finally, among the remaining supplements, we favored those without added sugar, binders, and fillers, as well as those which may include some additional benefits, such as the omega 3 fatty acids found in Nordic Naturals Vitamin D, and the leucine found in Thorne Research Vitamin D.
Vitamin D helps your body absorb calcium. For that reason alone, it’s crucial that we get enough of this important vitamin in our diets. After all, calcium (along with phosphate) is the essential building block of bones.
If you don’t get enough calcium in your diet, or if you aren’t absorbing the calcium you do consume, bone production and bone tissue are severely impacted.
A large number of people are deficient in vitamin D. It’s estimated that worldwide, around a billion people don’t get enough vitamin D (2). There are very few food sources of vitamin D, but beef liver, cheese, mushrooms, and egg yolks provide tiny amounts. Fatty fish provide even more, but the best way to get your vitamin D is to drink fortified milk, get at least 15 minutes of full sunshine on a large part of your body every day, or take supplements.
In fact, it’s very difficult to get all the vitamin D from food sources. Likewise, if you live in a northern part of the world it can be hard to get your vitamin D from sunshine, too. Not only that, but certain segments of the population have trouble getting enough of the vitamin from the sun, too: people with dark skin.
Finally, the elderly need more vitamin D than the rest of us. For all these reasons, vitamin D supplements are among the most widely necessary supplements on the planet.
Some evidence suggests that higher levels of vitamin D are protective against cancer. Thirty years ago, it was discovered that people living in northern areas had higher rates of colon cancer (3).
That led to the theory that lower vitamin D levels might increase colon cancer risk. Dozens of studies have been performed since then that strongly support the theory, but that doesn’t necessarily mean vitamin D supplements will lower the risk.
High levels of vitamin D may also prevent heart attacks. A 20-year study (4) found that men with vitamin D deficiencies had double the risk of having a heart attack. While more research is needed, this association may be related to the fact that vitamin D has been linked to your overall levels of inflammation.
Vitamin D has been established as safe at doses of at least 4000 IU per day, but there is a risk of adverse effects if you take extremely high doses for a long time.
What’s ‘excessive’? Even doses of 10,000 IU per day is not known to cause significant side effects in the general population (5). These side effects at very high doses can be serious, and include dysregulated blood levels of calcium.
People with thyroid conditions seem to be at a higher risk for vitamin D toxicity, because of the relationship between vitamin D and thyroid hormones.
For people who do not have thyroid problems, though, typical doses of vitamin D found in over the counter supplements pose little or no risk.
Current recommendations from medical governing bodies recommend that adults take 600 IUs of vitamin D per day and the elderly take 800 IUs of vitamin D per day (6).
However, the current recommendations have generated substantial controversy. One scathing review of the most recent recommendations pointed out that with 600 IUs of vitamin D per day as your only input of vitamin D, your blood levels of the metabolically active form of vitamin D would only be one-third of the minimum biologically healthy level (7).
Second, the recommendations for vitamin D intake as it stands are based solely on evidence for its role in bone health, not its role in preventing chronic diseases or improving physical performance.
What’s a typical dosage among adherents to the ‘more vitamin D is necessary’ hypothesis? Usually a few thousand IUs per day, though researchers note that people who are overweight and obese need higher doses (as with most supplements) to get the same effect as a lean person, simply because of their greater body mass.
In terms of dosage safety, up to 4000 IUs of vitamin D is known to be safe, based on experimental research. Higher doses are not known to be dangerous, but have not had their safety firmly established in controlled research settings.
Q: How is a vitamin D deficiency treated?
A: The treatment plan for a vitamin D deficiency depends on how low your blood levels of vitamin D are. For severely low blood levels, direct medical supervision is usually necessary.
This is diagnosed with a blood test for the 25-hydroxy form of vitamin D, which is the biologically active form. If your levels of 25-hydroxy vitamin D are extremely low, you might be given a massive initial dose to boost your levels of vitamin D rapidly, then sustain these levels with regular high-dose supplementation going forward.
Moderate to mild vitamin D deficiency is usually treated with a daily vitamin D supplement, typically that provides a few thousand IUs per day of vitamin D. If you are deficient in vitamin D, just taking the recommended 600-800 IUs per day for healthy adults is often not enough to actually raise your vitamin D levels.
Q: Can low vitamin D lead to weight gain?
A: There is strong evidence that vitamin D is related to being overweight or obese, but whether vitamin D deficiency will cause you to gain weight is less clear.
One study published in 2013 makes the opposite case: being overweight or obese disrupts hormone metabolism, which manifests as vitamin D deficiency (8).
This paper, which used genetic markers for vitamin D metabolism to study the causal effects of vitamin D on obesity, and vice versa, argues that obesity causes vitamin D deficiency, not the other way around.
From the perspective of preventing the negative health effects of vitamin D deficiency, the distinction is less important, as in either case people who are already overweight or obese may require vitamin D supplementation.
Q: What causes vitamin D deficiency?
A: The most proximal cause of vitamin D deficiency is a lack of exposure to enough sunlight for your body to synthesize vitamin D, or a lack of vitamin D in your diet.
Dietary vitamin D is very rare; it’s only found in significant amounts in fortified foods, and some mushrooms (which, incidentally, synthesize it the same way we do—by exposure to sunlight). So, if you are not getting outside and exposing your skin to direct sunlight, that’s the most likely cause of vitamin D deficiency.
Being overweight or obese seems to amplify the problem of vitamin D deficiency through disruptions in the body’s hormonal system, so even given the same amount of sun exposure, an overweight or obese person is more likely to develop vitamin D deficiency.
Q: Does vitamin D supplementation work?
A: Yes, as long as the dosage is high enough, vitamin D supplementation is a very successful strategy for raising levels of the biologically active form of vitamin D, which is the 25-hydroxy form (technically, 25-hydroxycholecalciferol).
Doctors have noted that it is difficult to effectively raise vitamin D levels with the moderate doses (600-800 IUs per day) recommended for healthy adults, so in cases of clinical vitamin D deficiency, doctors often use substantially higher doses, especially initially, to kick-start an increase in vitamin D levels in the blood.
Q: What does vitamin D do?
A: While named a “vitamin,” vitamin D is technically a hormone. It plays a critical role in skeletal health, and deficiencies in vitamin D (which go hand in hand with calcium deficiencies) are associated with a marked increase in risk for osteoporosis.
It also play a key role in metabolising other nutrients like magnesium too. Discoveries of its biological roles are still continuing to this day; it seems to play a link in both cognitive function and athletic performance as well.
Q: Is low vitamin D linked to depression?
A: Yes, one of the most under-reported threads on the science of vitamin D is its link to mental health. According to research that examined data from over 30,000 people, people with low levels of vitamin D have a more than two-fold increased risk of depression, compared to people who have high levels of vitamin D (9).
Among people with fibromyalgia, deficiency in vitamin D is also linked to anxiety as well as depression (10). While there are not as many randomized clinical trials of vitamin D for depression as there are for bone health and fracture prevention, the role of vitamin D in mental health should not be overlooked.
Vitamin D plays a critical role in the development and maintenance of good bone health, and evidence is accumulating that demonstrates a role in promoting heart health, longevity, and athletic performance, to name just a few other benefits.
It’s naturally synthesized by your body via exposure to sunlight, but in the modern world, many people are vitamin D deficient.
Groups at particularly high risk for vitamin D deficiency include people with darker skin, people who live in northern climates, and the elderly.
Current recommendations for minimum intake are 600-800 IUs per day, but many experts advocate doses of at least 1000-2000 IUs per day. Dosing of up to 4000 IUs per day is known to be safe.
Given the good safety profile of vitamin D and the wide range of detrimental effects associated with deficiency, you should seriously consider a vitamin D supplement if you don’t expose your skin to the sun on a regular basis throughout the year.
For Alpha XR’s #1 recommended vitamin D3 supplement, click here.