There is lots of research out now on vitamin D. It is actually a hormone and not a vitamin. It was misclassified as a vitamin when it was first discovered. You have vitamin D receptors all over your body proving it has influence on many biological processes. As time goes on science will learn more of what it does but below are just a few know positives about maintaining a high vitamin D level: It is an important immune system modulator. It is also important in helping calcium get into the bones and teeth. It helps insulin get into the cells slowing or preventing insulin resistance. It has been shown to reduce the risk of colon, breast, bladder, and thyroid cancer. It has been shown to reduce the risk of stroke. It can slow the onset of autoimmune diseases. It can help Most people to supplement. Especially those who can not get enough vitamin D from sun exposure. This is especially true of those living in Colder claimants as the angle of the sun is too shallow to be effective in receiving enough uv-b radiation needed to make D. You should get your Vitamin D levels measured every year at your annual physical with a 25-hydroxy vitamin D test. You may be surprised how low your level is. Most functional medicine doctors and ND's agree that a healthy level should be 50-100 ng/ml. Many lab ranges are 30-80. So be aware of this discrepancy. Many MD's still do not measure it and those that do subscribe to out dated lab ranges. It is best absorbed with your largest meal of the day and taking it with some fat helps in the absorption. This product is in olive oil (a very stable oil) which provide some fat. Beware of other D drops that are in less stable oils like sunflower oil. Oils like this can go rancid much easier. These drops are a very economical way to purchase your vitamin D and I have always been satisfied with Nature's Answers quality. If you found this review helpful, kindly visit my iherb home page for more value added reviews. "Yes" helpful votes are appreciated. Peace and good health
Posted by iHerb Customer on Apr 28, 2016 | Verified Purchase
Love the formula, hate the fact the drops will not come out easily. Very frustrating dropper. Will not buy again.
Posted by iHerb Customer on Nov 07, 2013 | Verified Purchase
It takes ages to get a single drop out of the dropper. This is very frustrating. This was not the case so I suppose they changed the dropper for safety reasons although there is no need since the cap has a safety lock. Other than that it is a good vitamin D3.
Posted by iHerb Customer on Feb 19, 2011 | Verified Purchase
I do not like the "dropper" for this product. It makes accurate dosing very difficult.
Posted by iHerb Customer on Mar 06, 2017 | Verified Purchase
It's difficult to drip out the liquid. As for the effect, it is still too early to tell.
Posted by iHerb Customer on Apr 01, 2017 | Verified Purchase
The only disadvantage is the flavor, but it is ok...
Posted by iHerb Customer on Dec 16, 2016 | Verified Purchase
Once I receive it I can say never order to uk as u have to pay a ridiculous custom of £15 to release as my customs
Posted by iHerb Customer on Dec 17, 2013 | Verified Purchase
I have been using these drops as a serum to heal my coldsore. It helped the recovery but if you were to take them orally the taste is very heavily olive oil flavoured.
Posted by iHerb Customer on Apr 18, 2011 | Verified Purchase
I have been taking this for a few weeks now but do not notice any change - no extra energy, etc.
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