Vitamin D – Dosage
How long does it take to increase 25-vitamin D levels after starting supplementation?
Healthy adults taking 1,000 IU of vitamin D a day reach their peak blood level within five to six weeks. When the patients are treated with 50,000 IU of vitamin D2 once a week for eight weeks to treat a deficiency, their blood level begins to increase by the first week and levels off by the eighth week of treatment.
Is there any advantage to taking smaller doses more frequently rather than one large dose per day?
There is no advantage to taking smaller doses more frequently rather than a large dose of 1,000 or 2,000 IU of vitamin D a day. Indeed, you can take 2,000 IU of vitamin D a day or 14,000 IU of vitamin D once a week or 60,000 IU of vitamin D once a month; they all work the same way.
Do you need to take a supplement even during the summer?
If you’re good about getting plenty of sensible sun exposure throughout the summer months, or you live in a sunny place like Florida, then you may not necessarily need to supplement. However, it’s much easier to get into the routine of taking a supplement year-round. And even Floridians have been shown to be largely deficient, because they avoid the sun or wear sun protection. You cannot overdose on sunlight exposure and become vitamin D intoxicated, so no matter how much sun you get during the summer, taking an additional 1,000 to 2,000 IU supplement cannot hurt you. It is recommended that everyone taking 1,000 to 2,000 IU of vitamin D a day along with a multivitamin containing 400 IU of vitamin D. This will not cause any buildup of vitamin D in the body, and by using this routine, you are less likely to forget it in the winter.
How many units of vitamin D would a person have to take to become toxic?
Vitamin D intoxication will not occur until a person is taking more than 10,000 IU of vitamin D a day for more than six months. Adults who received 10,000 IU of vitamin D a day for five months showed no signs of toxicity. You cannot overdose on vitamin D from exposure to sunlight or a tanning bed or a UVB-producing lamp, no matter how much UVB you get.
What is the best supplement for children who cannot swallow pills?
Infants can be administered vitamin D through pediatric vitamin drops. If you have children who cannot or will not swallow pills, you can crush a vitamin D tablet or squeeze the contents of a gel capsule into a glass of milk or juice. A good product that has emerged on the market and is a liquid form of vitamin D. Made by Wellesse, it contains 500 IU of vitamin D per teaspoon.
Does the recommended dose of vitamin D supplement need to be taken with fat (not in a tablet form)?
The recommended dose of vitamin D supplement does not need to be taken with fat. Vitamin D is equally bioavailable in corn oil, milk, and orange juice.
How should a vegan or vegetarian make sure he or she gets enough vitamin D?
Vegans should supplements with at least 1,000 IU of vitamin D a day, and preferably 2,000 IU. This would be in addition to a multivitamin. Vegans concerned about animal sources of supplemental vitamin D3 can opt for supplements containing vitamin D2, which comes from yeast.
What is the advice for vegan or vegetarian children?
It is recommended that all children, including vegan children, ingest at least 400 IU of vitamin D a day, and preferably 1,000 IU of vitamin D a day, along with a multivitamin, especially if they are not getting adequate exposure to sunlight.
If a person is not vitamin D deficient, what is the best over-the-counter form and dose to take? What if the person is vitamin D deficient?
If a person is not vitamin D deficient, to maintain a vitamin D sufficiency the person should take at least 1,000 IU of vitamin D2 or 1,000 IU of vitamin D3 a day in addition to multivitamin with 400 IU of vitamin D. if a person is vitamin D deficient, then double or triple the dose and he or she should take 2,000 to 3,000 IU of vitamin D a day along with a multivitamin. A person who is severely vitamin D deficient should consult a doctor to inquire about prescription-level treatment.
What form of supplementation do you recommend – D2 or D3?
1,000 IU of vitamin D2 is as effective as 1,000 IU of vitamin D3 in raising blood levels of 25-vitamin D. Either form can be used. But note: to raise blood levels of 25-vitamin D to above 30 nanograms per milliliter, you need to take more than 1,000 IU.
Is the prescription form of vitamin D different from what’s available over the counter?
In the United States, the only vitamin D form available by prescription is vitamin D2, also known as ergocalciferol. It comes either in a capsule with 50,000 IU of vitamin D2 or in a liquid form (for pediatric patients) with 8,000 IU of vitamin D2 per 1 milliliter. Vitamin D2 can also be found in some over-the-counter supplements, and it’s just as effective as vitamin D3.
