Can Too Much Vitamin D Be Toxic?

[Suzanimal]

As more Americans take vitamin D supplements, ​there has been concern that more people could experience toxic effects from very high vitamin D levels. But a new study shows that people rarely experience harmful side effectswhen taking large amounts of vitamin D.

Researchers analyzed information from more than 20,000 vitaminD blood tests performed on people living in Rochester, Minnesota, and the surrounding area over a 10-year period. They looked to see how many people had "high" vitamin D levels, defined as levels over 50 nanograms per milliliter. (Normal vitamin D levels are between 20 and 50 ng/mL.)

About 8 percent of the people had vitamin D levels over 50 ng/mL, but 0.6 percent had even higher levels, over 80 ng/mL, and 0.2 percent had levels over 100 ng/mL.

The researchers also found that the proportion of people with high vitamin D levels increased considerably during the study period — from 9 per 100,000 people in 2002 to 233 per 100,000 people in 2011. This spike is likely due to an increase in people taking vitamin D supplements, either because a doctor prescribed them or because they decided on their own to take them, the researchers said.

Despite this increase, the people in the study rarely experienced hypercalcemia, or high blood calcium levels that can occur as a result of high vitamin D levels. The condition can cause weakness, vomiting and kidney problems, and is the main side effect of high vitamin D levels.

In fact, there was no link between people's vitamin D levels and their blood calcium levels. [9 Good Sources of Disease-Fighter Vitamin D]

"We found that, even in those with high levels of vitamin D over 50 ng/mL, there was not an increased risk of hypercalcemia, or elevated serum calcium, with increasing levels of vitamin D," study co-author Dr. Thomas D. Thacher, a family medicine expert at Mayo Clinic, said in a statement.

The study identified just four cases over the 10-year period of people who had hypercalcemia associated with high vitamin D levels, and three of those were mild cases in which people did not have symptoms. (In those three cases, the condition was revealed only by the blood test.)

There was just one case of true vitamin D toxicity, in a 51-year-old woman who had vitamin D levels of 364 ng/mL. The woman had taken 50,000 international units (IU) of vitamin D per day for three months, along with calcium supplements, and went to the doctor with weight loss, vomiting and confusion. (The recommended upper limit for vitamin D supplementation is 4,000 IU per day.) The woman turned out to have kidney damage.

Doctors should ask their patients about vitamin D supplements that they are taking, because people can buy very high doses — as much as 50,000 IU — over the counter, Thacher said.

The study was published in the May issue of the journal Mayo Clinic Proceedings.

http://www.livescience.com/50765-vit...ort_code=2yeod

[jj-]

Of course. One vitamin that can be toxic but few people are aware is vitamin B6.

[juleswin]

This is just one study done with people living in Minnesota and Rochester which because of its longitudinal location and climate, the people there receive very little sunlight compared to people living in other parts of the country. But the rule of thumb is that you can get overdose toxicity from fat soluble vitamins A,D,E and K because they are stored in the fatty tissues in the body and you rarely get water soluble vitamin(B & C) toxicity because they are easily excreted from the body

[jj-]

But the rule of thumb is that you can get overdose toxicity from fat soluble vitamins A,D,E and K because they are stored in the fatty tissues in the body and you rarely get water soluble vitamin(B & C) toxicity because they are easily excreted from the body

I think it's bad to propagate that kind of thinking because B6 (water soluble) is more toxic that vitamin E in the form of mixed tocopherols, or vitamin K2 in the MK4 form.

Vitamins E and K, taken in the right forms, have practically no toxicity. So one can say that 50% of the fat soluble vitamins aren't toxic, which to me seems to invalidate the generalization that fat soluble vitamins are toxic.

[juleswin]

I think it's bad to propagate that kind of thinking because B6 (water soluble) is more toxic that vitamin E in the form of mixed tocopherols, or vitamin K2 in the MK4 form.

Vitamins E and K, taken in the right forms, have practically no toxicity. So one can say that 50% of the fat soluble vitamins aren't toxic, which to me seems to invalidate the generalization that fat soluble vitamins are toxic.

Its a rule of thumb for a reason, the reason being that it is far more easier to build up levels of fat soluble vitamins than it is to build up water soluble ones because fat soluble vitamins is store in the fatty tissues and water soluble ones get excreted with urine and feces. Also, I have never heard of vitamin B6 toxicity, what exactly happens to you when you have too much of it in your system?

[donnay]

http://www.livescience.com/50765-vit...ort_code=2yeod

How do I get the vitamin D my body needs?

The two main ways to get vitamin D are by exposing your bare skin to sunlight and by taking vitamin D supplements. You can’t get the right amount of vitamin D your body needs from food.

The most natural way to get vitamin D is by exposing your bare skin to sunlight (ultraviolet B rays). This can happen very quickly, particularly in the summer. You don’t need to tan or burn your skin to get vitamin D. You only need to expose your skin for around half the time it takes for your skin to turn pink and begin to burn. How much vitamin D is produced from sunlight depends on the time of day, where you live in the world and the color of your skin. The more skin you expose the more vitamin D is produced.

You can also get vitamin D by taking supplements. This is a good way to get vitamin D if you can’t get enough sunlight, or if you’re worried about exposing your skin. Vitamin D3 is the best kind of supplement to take. It comes in a number of different forms, such as tablets and capsules, but it doesn’t matter what form you take, or what time of the day you take it.

Different organizations recommend different amounts of vitamin D supplement to take each day. The Vitamin D Council recommends taking larger amounts of vitamin D each day than other organizations, because smaller amounts aren’t enough to give you what your body needs. Most people can take vitamin D supplements with no problems. However, if you have certain health problems or take certain medicines, you may need to take extra care.

Your body gets most of the vitamins and minerals it needs from the foods that you eat. However, there are only a few foods that naturally contain any vitamin D. Most foods that contain vitamin D only have small amounts, so it’s almost impossible to get what your body needs just from food.

Because there are only small amounts of vitamin D in food there are only two sure ways to get enough vitamin D:

Exposing your bare skin to sunlight to get ultraviolet B (UVB).
Taking vitamin D supplements.


Continued...


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New Analysis Claims Vitamin D Supplements Are Useless -- Here’s Why It’s Wrong



By Dr. Mercola

Last November, researchers at the Kaiser Permanente Center for Health Research1 declared that vitamin supplements are probably useless when it comes to preventing heart disease and/or cancer.

Their seriously flawed analysis (which, sadly, is being used by the US Preventive Services Task Force to update its recommendations on supplement use) was widely reported by the media.2

Now, the attack against vitamin supplements has heated up yet again—this time they're trying to quell the idea that vitamin D, specifically, has any useful purpose for the average person.

Numerous media sources3, 4 have trumpeted the findings of a recent meta-analysis,5 which claims that vitamin D supplements are not only useless against heart disease, stroke and cancer, but may do more harm than good, and that further investigation into vitamin D would likely be "pointless"! According to the authors of the study:

"Available evidence does not lend support to vitamin D supplementation and it is very unlikely that the results of a future6 single randomized clinical trial will materially alter the results from current meta-analyses."

What's more, they also found that people taking vitamin D supplements had an increased risk for hip fracture, which prompted Professor Karl Michaëlsson, a researcher at Uppsala University in Sweden, to publish a call for stricter labeling on vitamin D supplements. In his editorial,7 which accompanied the featured analysis, he writes:

"Without stringent indications -- i.e. supplementing those without true vitamin D insufficiency -- there is a legitimate fear that vitamin D supplementation might actually cause net harm."

It should be noted that the dose given to the women in the study with increased fracture rates was 500,000 IU, all in one dose. This is an intake the body cannot absorb and process properly and the toxicity of the dose itself was not a surprise to the vitamin D researchers. The increased fractures were seen shortly after the huge dose but the rate declined in later months.

Continued...

[jj-]

Its a rule of thumb for a reason, the reason being that it is far more easier to build up levels of fat soluble vitamins than it is to build up water soluble ones because fat soluble vitamins is store in the fatty tissues and water soluble ones get excreted with urine and feces. Also, I have never heard of vitamin B6 toxicity, what exactly happens to you when you have too much of it in your system?

Neuropathy, for example. You can't feel your feet.

[juleswin]

Neuropathy, for example. You can't feel your feet.

Ok, just learned something new today. Thanks

[Acala]

The risk of too little vitamin d is FAR greater than the risk of too much. Most people living in the USA are already deficient, and that is compared to a standard that is probably insufficient. Unless you have some kind of unusual metabolic problem, you can and should take at least 4000 IU a day. You can probably take ten times that amount before you have any toxicity.

[donnay]

The risk of too little vitamin d is FAR greater than the risk of too much. Most people living in the USA are already deficient, and that is compared to a standard that is probably insufficient. Unless you have some kind of unusual metabolic problem, you can and should take at least 4000 IU a day. You can probably take ten times that amount before you have any toxicity.

I agree.

Another thing is if you are dark skinned, you need far more amounts of Vitamin D.


Lack of Vitamin D May Explain Black Americans' Cancer Deaths

Are You Getting Enough Vitamin D?

[brushfire]

When I took field survival, they said that polar bear liver could not be consumed, due to its toxicity (vitamin a and d, if I recall). I guess that its so concentrated that one would die of an overdose.

[Suzu]

I live in the mid-south which is still a temperate climate. I take 5k IU of D-3 daily in winter months. I skip days when I've eaten food rich in D-3 like certain fish. So far, no unwanted side effects. If I feel a "cold" or something coming on, I take a double dose of D-3.

It's important to remember that your skin won't produce D-3 from sunlight if you use soap on it within 48 hours of your sun bath. It's fine to wash your hair and armpits and crotch with soap but the rest of the body should just be washed with water and a cloth.

Also worth noting is that your body cannot make full and effective use of D-3 without also having sufficient Vitamin K. Best sources of Vitamin K are smelly fermented foods like brie cheese, natto, and kim-chee. I use a lot of natto because aside from Vit. K it is rich in many other healthful nutrients. If you'd like my recipe for making natto at home, send me a PM.