5 Best Vitamin D Supplements, When and How to Take with Dosages

By Leo Tat @AuthorityDiet

It's known as the ​"sunshine vitamin.​" Vitamin D is an essential nutrient which your body produces when you are exposed to sunlight.

Indeed, if you do not get a lot of sunlight, there is a good chance you are also not getting enough vitamin D. For this reason, vitamin D supplements are commonly recommended by physicians.

In this article, I am going to tell you everything you need to know in order to shop for the highest quality vitamin D supplements.

But first, let's talk a little bit more about vitamin D itself. In particular, I want to discuss the many benefits of this nutrient for your health.

I also will tell you more about why vitamin D deficiency is so common, and how you should go about taking vitamin D supplements to add more nutritional goodness to your diet.

Health Benefits of Taking Vitamin D Supplements

First of all, why does your body need vitamin D, and how can taking more vitamin D improve your well-being?

Here are some of the scientifically-backed benefits which researchers have discovered:

  • Reduce your chances of developing multiple sclerosis (MS), and even slow its progression if you do have it (6, 7).
  • Fight against the flu (8).
  • Treat respiratory ailments such as asthma and improve immune health (9, 10).
  • Reduce your overall chances of dying from a range of maladies (11, 12).
  • Possibly prevent the development of cancer (13).
  • Reduce anxiety and depression (14, 15).
  • Lose weight if you take vitamin D along with calcium while eating a healthy diet and working out (16).
  • Reduce the risk of type 1 diabetes in childhood (17).
  • Also reduce your risk of developing type II diabetes in adulthood (18).
  • Reduce fractures and falls in the elderly (19).
  • Possibly help treat leukemia (20).
  • Boost your brain health, potentially helping to prevent the development of diseases such as cognitive decline and dementia (21).
  • Take vitamin D along with sodium fluoride and calcium to treat osteoporosis (22).
  • Reduce the chances that you will develop stress fractures, musculoskeletal pains, and illness as an athlete (23).
  • Potentially improve protein synthesis, gene expression, and electrolyte metabolism, increasing performance during workouts and building muscle strength (24).

Look into some of these studies. I think you will be impressed by just how much vitamin D can do for you.

When you are short on it, your body does not have the resources it needs for you to stay healthy. By taking higher dosages, you can treat specific conditions.

In fact, I recommend that you take a few minutes to peruse my full article on this topic, 16 Benefits of Vitamin D. There I go into all of these health benefits in detail and share even more studies with you.

​Who Needs to Take Vitamin D Supplements?

​"But I eat a healthy diet. I am already getting all the nutrition I need from my food, right? Do I really need a vitamin D supplement?​"

Actually, not a lot of foods are rich in vitamin D at all. Here is a list of those which are:

The brevity of this list is one of the reasons why vitamin D deficiency is common.

You pretty much need regular, adequate exposure to direct sunlight to get enough vitamin D. Diet alone simply is not going to cut it.

As to the matter of sun exposure, there are quite a few people who do not get enough. For example:

  • If you live in a cloudy area such as the Pacific Northwest, you probably do not get enough vitamin D through sunlight for most of the year.
  • Work 9-5 without a window and no chance to go outside? You are being deprived of vital sunlight.
  • Live at a latitude where the sun only rises for a few hours of the day during the winter months? This is another reason you might be getting insufficient vitamin D.
  • Genetics plays a role as well. The average risk for vitamin D deficiency is 41.6%, but it rises to 69.2% if you are Hispanic, and 82.1% if you are black (25).
  • The elderly have a heightened risk for vitamin D deficiency (26).
  • Those who have iron deficiency issues may also have vitamin D deficiency. Why? You need that iron to absorb vitamin D effectively.

I cannot underline enough that vitamin D deficiency is very real. If you want an anecdote about the pervasiveness of vitamin D deficiency, I can tell you one from my own life.

​My friend used to live in Southern California, where obviously there was plenty of sunlight. ​He then moved up to the Pacific Northwest.

Since doing so, ​he have been told repeatedly by doctors​ that everyone living in this part of the world needs to take a vitamin D supplement in order to get sufficient vitamin D.

Those who fail to do this also fail to get enough vitamin D. As a result, they eventually start developing symptoms of deficiency.

Vitamin D deficiency can have serious consequences:

  • A higher risk for developing osteoporosis (27).
  • There is a link between heart attacks and vitamin D (28).
  • You have a heightened risk for MS, dementia, cancer, diabetes, and heart disease (29).

So you can see that vitamin D deficiency is serious business. If you are in an at-risk category, it is particularly important to take a supplement.

Even if you do live in an area with plenty of sunlight and you have a need to increase your vitamin D intake, a supplement is a better option than sun exposure.

Sun exposure can and does help, but if you overdo it, you could suffer the harmful effects of UV rays.

Not in an at-risk group? You can still benefit from taking vitamin D.

You already are aware of the numerous health benefits. Build off of your existing foundation of good health by giving your body even more nutrition.

With a vitamin D supplement, you will be protecting your health over the years to come.

​Vitamin D Dosage

So how much vitamin D do you actually need to take?

These are the guidelines released by the National Institute of Health:

  • Birth to 12 months - 400 IU
  • Children 1-13 years - 600 IU
  • Teens 14-18 years - 600 IU
  • Adults 19-70 years - 600 IU
  • Adults 71 years and older - 800 IU
  • Pregnant and breastfeeding women - 600 IU

​How Much Vitamin D Can You Take?

You will notice that a lot of vitamin D supplements include a fairly high dosage.

This leads to the next obvious question. How much vitamin D is too much?

If you wanted to go by the recommendations from the National Institute of Health, these would be the upper limits:

  • Infants: 1,000-1,500 IU
  • Children aged 1-8: 2,500-3,000 IU
  • Children ages 9 and up as well as all adults: 4,000 IU

You do not have to use these as the upper limits, however.

The Food and Nutrition Board which came up with these limits has also recorded the following:

    10,000 IU/day is the No Observed Adverse Effects Level (NOAEL) for adults.

That means exactly what it sounds like it does. At 10,000 IU/day, there are no research studies indicating any adverse side effects.

So if you want to take 10,000 IU of vitamin D per day, you can do so safely without any concerns.

And actually, depending on the reasons why you are taking vitamin D supplements, you may have to do this if you want to achieve the desired effect.

You will want to take a look at this study ( 30).

Basically, a 25(OH)D serum level above 30 ng/mL is necessary to treat a range of different health conditions.

The researchers conducting the study wanted to find out how much vitamin D participants actually would have to take to reach this serum level.

They ended up prescribing 25,000 IU of vitamin D in multiples to the participants.

Even this high dosage did not yield the desired serum level for everyone who participated in the study.

So naturally a much lower serum level - like the 4,000 IU recommended upper limit - would not be sufficient.

For this reason, the scientists reached the conclusion, ​"if a 25(OH)D level of 30 ng/mL or more is targeted in future studies, higher doses than the IOM Upper Limit should be used.​"

So you should strongly consider taking more than 4,000 IU. Consider taking up to 10,000 IU, especially if you do have a condition which will not respond to a lower treatment level.

​How Much Vitamin D Is Too Much?

Since 10,000 IU is the NOAEL, you can play it safe by sticking with that as your upper limit.

But as some studies indicate, you may still be fine if you exceed that.

Vitamin D toxicity, also known as " hypervitaminosis D​" does exist, so it is possible to take too much. It is however far from common.

Usually vitamin D toxicity requires overexposure across an extended span of time. During this time, symptoms may not manifest right away. After a few months however, they can become quite obvious.

At what levels of intake have researchers observed hypervitaminosis D?

So far, toxicity has been observed at levels ranging from 40,000-100,000 IU ( 31, 32, 33, 34, 35).

So that is a lot of vitamin D. If you are taking closer to 10,000 IU, you are far from that range.

​Are There Vitamin D Side Effects?

If you do take too much vitamin D (unlikely, given that you are taking a reasonable dosage as just discussed), you could experience side effects like:

  • Weakness
  • Fatigue
  • Headache
  • Dry mouth
  • Low appetite
  • Nausea and/or vomiting
  • A metallic taste in your mouth

If you are taking vitamin D in the proper amount, you should not have any of these side effects.

​Protect Your Nutrient Stores

Even though vitamin D supplementation has no side effects at safe doses, high amounts of vitamin D may upset your nutritional balance.

A higher intake of vitamin D can result in vitamin K stores being depleted ( 36, 37).

This is a problem, because calcium can become deregulated if you are low on vitamin K.

If this happens, you can experience problems such as calcification and declining bone health.

To protect against this issue, raise your intake of the following nutrients when you increase your vitamin D:

Vitamin A provides a level of protection for your vitamin K stores, while magnesium protects bone health.

Research supports this particular combination as effective ( 38, 39, 40).

Is There Anyone Who Should Be Cautious About Taking Vitamin D Supplements?

Vitamin D is safe for most users.

But you should observe the following precautions:

  • If you are pregnant or breastfeeding, you should limit your intake to 4,000 IU.
  • If you have kidney disease, calcification is a particular concern, so talk to your doctor before you start vitamin D supplements.
  • If you already have elevated calcium levels in your blood, this condition could be exacerbated through vitamin D supplementation.
  • If you have atherosclerosis, which is a condition where your arteries are hardened, it may be aggravated further through vitamin D supplementation.
  • If you have sarcoidosis, watch out for kidney stones or other complications which may ensue if your calcium levels go up.
  • Histoplasmosis is another condition which may be sensitive to higher levels of calcium in the blood. Once again, proceed with caution.
  • If you have an overactive parathyroid gland, you should be wary of the effects of calcification.
  • Those with lymphoma should take special care to make sure that their calcium levels are controlled when taking vitamin D.
  • Tuberculosis is one more condition which requires careful monitoring of calcium levels. So be careful when taking vitamin D.

If you are in any doubt, you can always consult with your health practitioner.

​How to Shop For a Quality Vitamin D Supplement

Now you know all about the importance of vitamin D supplements, and you understand safe dosages, side effects, health benefits, and more.

Let's talk about what you should look for in a high quality vitamin D supplement:

A dosage that makes sense.

Some users may need to take 10,000 IU of vitamin D each day, while others may only need 4,000 IU. Still others may opt for higher doses. Shop for a dose which is a fit for your condition.

Easy to digest.

As with any other supplement, you should shop for a product which you can swallow and digest with ease. Check user reviews to see if others had difficulty or found the tablets easy to digest.

Free of binders and fillers.

There are a lot of supplements out there which have additives like sugar. This is unnecessary. Try and find a vitamin D supplement which is free of these pointless, unhealthy fillers.

The best value.

Account both for the number of capsules and how much vitamin D is in each when you calculate whether or not the price is worth it for a given product.

Vitamin D with added nutrients if needed.

If you have a sensitive condition, you may want to shop for vitamin D which includes vitamin K, vitamin A and magnesium (or you can just take a multivitamin which contains those nutrients).

How and When To Take Vitamin D

First, choose a dose that meets the needs of your condition. For example:

  • For osteoporosis: 400-1,000 IU per day
  • To prevent falls: 800-1,000 IU per day
  • To prevent MS: 400 IU per day or more
  • To prevent cancer: 1,400-1,500 mg per day
  • For muscle pain from statins: 400 IU per day
  • To prevent influenza: 1,200 IU per day

Is there a right way to take vitamin D?

You may have heard that you should take vitamin D with a meal due to vitamin D being a 'fat-soluble vitamin.'

This study ( 41) did find that taking vitamin D with monounsaturated fats (such as you would find in olive oil) improved absorption.

Nevertheless, the results were not very dramatic. Taking vitamin D with fat was not much more effective than taking it without it.

Plus, some animal research studies have shown just the opposite effect.

There are also studies ( 42) which show that vitamin D in an oil carrier seems to produce a more pronounced serum response than vitamin D which is contained in ethanol or in a powder form.

So far, though, this is another difference which is not particularly noteworthy since it is so minimal. So as of right now, no, there does not appear to be a ​"best" way to take vitamin D.

You can take the supplement with or without fat, and in any form you feel comfortable with. Absorption rates probably will not be greatly impacted.

More research is needed before we can be sure what the exact effect of different vehicles (powder, oil, etc.) is, and whether fat increases or decreases absorption.

​Forms of Vitamin D Supplements

As just mentioned, vitamin D supplements do come in a few different forms:

  • Liquid tinctures: These come with eyedroppers so that you can measure out the dosage.
  • Tablets: This is self-explanatory. You can buy vitamin D in a basic tablet form which you take with water.
  • Capsules: Vitamin D capsules usually contain the vitamin D in a liquid form. Generally these are soft and go down easily.
  • Powder: Vitamin D is available in a loose powder form as well, which again allows you to measure out the dosage as you wish.

You already know that none of these forms is really superior for absorption going by current studies.

So how do you decide which form to buy?

Each form has some pros and cons. For example:

  • Liquid tinctures may be more convenient for patients who struggle to swallow tablets or capsules, but they may also be hard to measure with precision.
  • Vitamin D tablets are harder to swallow than gel caps, but they also tend to be cheaper.
  • Vitamin D capsules are a great middle ground if you want to save money over a tincture but want something which is easier to swallow than a tablet form.
  • Vitamin D powder has to be measured out with care, but you can stir it into smoothies and juice drinks. The loose powder may also save you money.

So that gives you some idea what to think about when selecting the form of vitamin D you want to buy.

​​​​Vitamin D2 vs. Vitamin D3​

Finally, you will notice that most vitamin D products available fall under the category of vitamin D3.

But occasionally you may run into a different form of vitamin D for sale, like vitamin D2. Which should you be purchasing?

The answer to this question is simple and straightforward.

Vitamin D3, called "cholecalciferol," is the type you want. The reason is that this form is the same one that your body manufactures when you are outside in the sunshine.

So when you take vitamin D3, you are giving your body the exact form it would produce on its own in response to the sun.

​Top Recommended Vitamin D Supplements

Now you know everything you need to in order to shop for the most effective vitamin D supplements.

So let's take a look at a few top recommended products. All of these are popular sellers online.

Recommended Vitamin D Capsules

Please note that some customers complained of a "cloudy​" appearance to the capsules.

This is not a sign of poor manufacturing, inconsistent ingredients, or capsules gone bad. It simply has to do with the fact that unrefined coconut oil was used as a carrier fluid.

Coconut oil gets cloudy in colder temperatures. It clarifies again in the heat. So you may notice differences from capsule to capsule, and the same capsules may look different from day to day.

What Viva Naturals High Potency Vitamin D3 Is Best For

These vitamin D capsules are an excellent all-around choice if you want to take 5,000 IU or more each day. Because they are pure and contain only natural ingredients, they are among our top recommendations.

Recommended Vitamin D Powder

​Recommended Vitamin D Tincture

Conclusion: With a High-Quality Vitamin D Supplement, You Can Protect Your Long-Term Health

Even in first world countries, vitamin D deficiency is surprisingly common. So take steps to restore healthy vitamin D levels and bolster them as needed to prevent and treat a range of health conditions.

All in all, I would say that the best vitamin D supplement on the market today is the Viva Naturals High Potency Vitamin D3, which is cost-effective and pure.

Take vitamin D over the long term, and you can continue to enjoy its potent effects, maintaining the health of your cardiovascular system, brain, immune system and more.