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When considering the best vitamin D tablets to take, the dosage of the tablet must be considered, as vitamin D can easily be overused and lead to toxicity levels within the human body. In addition to the dosage variable, there are other differences to consider, including the frequency one must take the pill and the form of the supplement. People taking vitamin D tablets must also remember to consider all sources of vitamin D, including sunlight and everyday foods, when considering a vitamin D tablet.
Liquid supplements are preferred mostly due to the ease of absorption by the human body, but other forms are available just like with other vitamins, such as tablets, capsules and softgels. The dosage of each drop or tablet is labeled on the package. Some manufacturers suggest taking two or more pills daily to reach the recommended dosage in order to supplement a diet.
Even with modern science, the dosage of vitamin D tablets recommended by researchers still varies greatly. The US Institute of Medicine of The National Academies suggests a goal of 200 international units (IUs) per day for people up to the age of 50, with the dosage increasing with age. This amount is generally considered low, and some research indicates as many as 1-2,000 IUs per day or more should be the recommended intake.
There are 5 forms of vitamin D, with the most common being D2 and D3. Vitamin D3 is manufactured by humans, and is therefore thought to be a more effective supplement than D2. Vitamin D2 is manufactured by invertebrates and some plants and fungi. Both forms are found as a vitamin D supplement, but research is proving that D3 is absorbed better by the body.
There are inherent dangers to taking too many vitamin D tablets as a supplement to natural sources. These side effects include headaches, nausea, vomiting, weakness, kidney stones and eventually renal failure. Limitations are also placed on pregnant and nursing women. Since vitamin D can be passed from the mother to the child, the child can endure the effects of toxicity and in severe cases can suffer mental retardation or other birth defects.
It is easy to take too many vitamin D tablets if one doesn’t consider natural sources like sunlight and some fortified foods. Every person with just a few minutes’ exposure to the sun is manufacturing some amount of vitamin D in their body already. Once fortified foods are considered, the amount of vitamin D necessary in a supplement can drop dramatically.