Why do so many vitamin supplements provide 200%, 500% or greater of the recommended daily value?
A great question was asked by a commenter, why do so many vitamins offer far more than the recommended daily value intake? The short answer: Pills are not a very good delivery method of vitamins. When your body eats, it kicks into digestion mode, and absorbs nutrients and vitamins efficiently. If you only take a pill, your body does not go into digestion mode, so it does not as efficiently absorb the vitamins. To compensate for the loss of absorption, pills often contain a greater than the required amount.
Taking vitamins with food helps aid in absorption, but be sure to follow the directions on the bottle, without an actual medical condition requiring extra vitamins, you aren’t going to benefit from absorbing twice the recommended amount. Gummy vitamins may work better, but more than likely their only measurable benefit over non gummy vitamins are that kids are more likely to take them. There are not enough calories in a gummy vitamin to put your body in digestion mode.
Can you overdose on vitamins?
It’s possible but unlikely. Concoctions like Emergin-c or 5-Hour Energy have upwards of 1000% percent of your vitamin c and b, but because those two vitamins are water soluble, your unlikely overdose on them, you just pass the surplus in your urine. Fat soluble vitamins however are a little different. The excess is stored in your fat and if you go through a process where you lose a lot of fat, you risk releasing a large amounts of the stored vitamins, potentially making you sick.
There are a few vitamins you should be particularly careful with. Adults who regularly far exceed the 4,000 international units (IUs), the daily safe upper limit for vitamin D, could end up with serious heart problems.
Folic acid is another, added to enriched grain products such as white flours, pasta, rice, breads, and cereals, help prevent birth defects in babies due to folic acid deficiency in pregnant women. While folic acid fortification has cut the number of birth defects by 25% to 50%, it might have created other health concerns in people getting too much. It’s not hard to get more than 1,000 micrograms of folic acid a day (the safe upper limit for adults) from fortified foods and supplements on a regular basis. Doing so might hide the signs of a vitamin B12 deficiency in older adults. Vitamin B12 deficiency can sometimes lead to permanent nerve damage if left untreated (1).
Generally speaking, most of us can receive the right amount nutrition from proper eating habits. If you do require supplementation, keep a log and be sure to read the labels carefully.