Are You getting Enough Vitamin D?

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You know that vitamin D could be a good defense against the flu. But are you getting enough? At Mercola.com, Dr. Joseph Mercola explains that official recommendations for vitamin D are inadequate. He writes:

Two studies published in November 2023 demonstrated that the current governmental dosing recommendations for vitamin D may not help you achieve optimal levels;¹ a third found a personalized approach to supplementation yielded better results in athletes than a one-size-fits-all approach.²

Vitamin D is a fat-soluble vitamin, also called calciferol. While it can be found naturally in some foods, your body endogenously produces vitamin D when your skin is exposed to ultraviolet rays from the sun. In the U.S., vitamin D supplements are available as vitamin D2 (ergocalciferol) and vitamin D3 cholecalciferol).³ Ideally, you can optimize your vitamin D through sensible sun exposure.

However, many are simply unable to get sufficient levels from the sun alone and need a supplement. On a typical sunny day,⁴ your body can produce up to 25,000 international units IU of vitamin D. Yet, the current recommended intake⁵ is only 600 IU for people between the ages of 1 and 70 years, and 800 IU for those over 70 years.

Two studies⁶ presented before the American Heart Association’s Scientific Sessions 2023 in Philadelphia demonstrated that the current recommended intakes are far lower than needed to boost your vitamin D to optimal levels. And, as we’ll discuss below, when your vitamin D levels are insufficient or deficient, it increases your potential risk for several health problems.

Current Recommendations Won’t Raise Vitamin D to Optimal Levels

The two studies⁷ presented in November 2023 were from Intermountain Health in Salt Lake City. The data suggest that when research trials are studying the effectiveness of vitamin D treatment to prevent heart disease, it was essential to use sufficient doses to raise vitamin D levels; otherwise the data would be inaccurate.

As the researchers wrote, past studies have demonstrated that low levels of vitamin D are associated with a higher risk of a cardiac event, such as a heart attack or stroke. The lead author, Heidi May, Ph.D., is an epidemiologist at Intermountain Health. She commented on the implications of their findings in a press release:⁸

“We’ve seen a series of studies that report an association between low Vitamin D and poor heart outcomes, but also a few randomized clinical trials that do not report the same association.

Our findings here show that just giving patients some Vitamin D does not help them achieve optimal levels. If researchers are going to further look at Vitamin D dosing as a possible way to improve heart health, patients need to be given the right doses to reach those ideal levels.”

The data showed that without using a personalized approach to supplementation and evaluating blood levels, patients may not have the expected results. Patients were enrolled in a randomized clinical trial to evaluate whether a personalized approach to supplementation could reduce heart-related outcomes. In the first Target-D study, researchers engaged 632 patients and split them into two groups.

The first group received a general recommendation to speak with their health care practitioner about a vitamin D treatment and the second group received a targeted vitamin D treatment. The goal was to raise their 25 hydroxyvitamin D (25[OH] vit D) level to more than 40 nanograms per milliliter (ng/ml), which is the level this study determined was optimal.⁹

Patients in the intervention group had their supplementation dosage determined by an algorithm and every-three-month blood serum assessment to adjust the dosage until their levels reached over 40 ng/ml. In the treatment group, nearly 90% required vitamin D supplementation, and of those, 86.5% needed more than 2,000 IU per day and 14.6% needed more than 10,000 IU per day to reach the serum level goal.

It took three months for less than 65% to achieve 40 ng/ml and six months or more for another 25% to reach the goal. The goal of the second analysis is to determine whether a sufficient level of vitamin D could help prevent heart attacks and stroke.

The participants had to have a heart event within 30 days of enrollment. The trial is planned to continue until at least 104 patients have experienced another heart event or die from heart disease.

In the intervention group, those with a vitamin D Level under 40 ng/ml began with a starting dose of 5,000 IU, which the researchers point out is well over the 600 to 800 IU that is currently the recommended dietary allowance. Viet T. Le is a cardiovascular researcher and physician assistant at Intermountain Health. He commented on the importance of accurate dosing in a press release:¹⁰

“If Vitamin D can help prevent heart attacks, we want to know it, but our findings are showing that you can’t just tell someone to take a single low supplement dose, then set it and forget it. We need to be more intentional in these trials in order to determine if there is a link between Vitamin D supplementation and improved heart health, as well as how to dose it to help our patients if it does.”

It was great that the study used blood levels as an endpoint as many studies fail to do this. However, they seem to have left out some key issues that are mentioned below:

• The best source of vitamin D is from the sun, not a supplement, as it provides far more than vitamin D, as I mentioned in an article in 2022.
• If you do get adequate sun exposure one day, it is important not to take a vitamin D supplement on that day.
• Vitamin K2 and magnesium are important cofactors to produce vitamin D, and if you aren’t getting enough in your diet or with supplements, you may be unable to get high enough vitamin D levels.
• The typical adult dose of vitamin D to produce healthy levels would be 8,000 units per day.

Read more here.