D3 how much is too much

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Show references Dawson-Hughes B. Vitamin D deficiency in adults: Definition, clinical manifestations, and treatment. Accessed March 20, Vitamin D. Office of Dietary Supplements. Hormone Health Network. Natural Medicines.

Marcinowska-Suchowierska E, et al. Vitamin D toxicity — A clinical perspective. Frontiers in Endocrinology. Can zinc supplements help treat hidradenitis suppurativa? So, what is the correct dose? And, how much is too much? But it has been more difficult to clearly establish the optimal dose of vitamin D. When we designed this study, there remained a question whether there's more benefit in taking a higher dose.

The study followed volunteers between the ages of 55 and 70 in a double-blind, randomized clinical trial to test the hypothesis that with increasing doses of vitamin D, there would be a dose-related increase in bone density and bone strength.

A third of the study participants received IU of vitamin D per day, a third received 4, IU per day, and a third received 10, IU per day. Volunteers had both their bone density and bone strength measured using a new, high-resolution computed tomography CT scan of bone at the wrist and ankle, called an XtremeCT, used only for research. The XtremeCT, located in the McCaig Institute's new Centre for Mobility and Joint Health, is the first of its kind in the world, and allows researchers to look at bone microarchitecture in detail never seen before.

Standard dual-X-ray absorptiometry DXA bone density was also obtained. Participants received scans at the start of the study and at 6, 12, 24 and 36 months.

To assess vitamin D and calcium levels, researchers also collected fasting blood samples at the beginning of the study and at 3, 6, 12, 18, 24, 30 and 36 months as well as urine collections annually. Bone mineral density BMD is determined by measuring the amount of calcium and other minerals in a defined segment of bone. The lower the bone density, the greater the risk for bone fracture. Adults slowly lose BMD as they age, and the DXA results showed a modest decrease in BMD over the duration of the study, with no differences detected between the three groups.

However, the more sensitive measurement of BMD with high resolution XtremeCT showed significant differences in bone loss among the three dose levels. Total BMD decreased over the three-year period by 1. The conclusion was that, contrary to what was predicted, vitamin D supplementation at doses higher than those recommended by Health Canada or Osteoporosis Canada were not associated with an increase in bone density or bone strength. Instead, the XtremeCT detected a dose-related decrease in bone density, with the largest decrease occurring in the 10, IU per day group.

More research is required to determine if high doses may actually compromise bone health. To diagnose vitamin D toxicity, a physician will administer a blood test that will show how much calcium is in the blood. If a person has vitamin D toxicity, then calcium levels will be abnormally high.

Ross notes that taking consistently high levels of vitamin D over long periods of time may not cause apparent toxicity in the short term, but may contribute to a higher risk of common symptoms further down the line. If a person shows signs of vitamin D toxicity, the first step toward treating it is to immediately stop taking any and all vitamin D and calcium supplements , as well as reducing intake of foods rich in vitamin D like salmon and cod liver oil.

Doctors may also administer medications to help the body metabolize less vitamin D and pass more calcium. You may also be prescribed bone resorption inhibitors. These medications are usually used to treat osteoporosis because they prevent the release of calcium into the bloodstream. However, Price's research has shown that bone resorption inhibitors may also prevent acute episodes of vitamin D toxicity.

These inhibitors, he says, could be useful to prevent calcification of soft tissue in patients who, for health reasons, can't reduce their intake of vitamin D.

For most people, though, the answer will be to simply stop your supplements, which will allow your body to process the excess calcium and, over weeks or months , return to normal. Vitamin D is a nutrient that helps your body absorb and regulate calcium. Therefore, it plays an essential role in helping you grow and maintain bone tissue throughout life.

Our bodies get vitamin D in two ways: through sun exposure and from certain foods. How much you need depends on your age, according to the National Institutes of Health. For example, adults require less than people over 70, who produce less vitamin D through their skin.

The National Institutes of Health recommend that most adults need international units IU each day to cover their basic needs for bone health. However, for overall health, it's best to get somewhere between IU to 4, IU per day. Fish is a great way to cover your bases , while vegans and vegetarians can look to almond milk and mushrooms. Three ounces of fatty fish, like salmon, or a cup of portobello mushrooms will take care of your daily vitamin D needs.

Ross says that if you occasionally consume the maximum recommended amount — 4, IU — it won't hurt you. But if you are consistently reaching or exceeding this limit for months or years on-end, that's when it may lead to symptoms of toxicity. Ross says that the vitamin D your skin produces through sun exposure is hard to quantify but in general, it's supplements — not sunlight — that tips the scales towards toxicity. If you get a severe sunburn, for example, you should be more concerned about skin damage than vitamin D toxicity.