Each day I take a multi-vitamin and a cod liver oil tablet (along with creatine and L-Glutamine). Both of these tablets claim to contain 100% RDA (Recommended Daily Amount) of Vitamin A. I take these last thing at night (except the creatine which is before/after workout).

I believe that too much Vitamin A is not good for you, and going above the RDA by twice as much of anything probably isn't a good idea. But there is no way to avoid it as both capsules have 100% RDA.

Am I risking damaging my kidneys by giving them too much Vitamin A to process in one go? Should I take the cod liver oil in the morning, and the multivitamin in the evening? Or vice-versa?


2 Answers 2


Unless you're doing something stupid like eating polar bear liver, hypervitaminosis A is the result of long-term overconsumption: taking one supplement in the morning and one in the evening is no more or less dangerous than taking both at once.

According to the National Institutes of Health, the level of vitamin A overconsumption that presents a long-term risk to a healthy adult depends on the form that the vitamin is consumed in. For pre-formed vitamin A (retinoids), the upper level is about three times the RDA, while for vitamin-A precursors (carotenoids), there is no known toxic effect for overconsumption, though it may raise the lung cancer risk of smoking or working with asbestos.


Most vitamins are best taken with some sort of food to aid in the absorption of the supplement. Taking vitamins throughout the day at different intervals also aids in maintaining proper levels of each supplement. Thus, taking vitamins in smaller dosages throughout the day provides optimal balance.

If you are taking vitamin supplements with no contraindications to any prescriptions and your choice is to take them all at night or not at all, you are not creating a problem by taking them all[enter link description here][1] at once.

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