Ever taken a vitamin and realized they were past the expiration date? Here’s what you need to know about expired vitamins.

Most vitamin bottles have a date on them, but, technically, that is not the expiration date. The reason is that vitamins don’t expire in the conventional sense.

In other words, vitamins do not become unsafe when they "expire." Moreover, the Food and Drug Administration (FDA) does not mandate putting a date on the bottles. Nevertheless, most manufacturers do put the expiration date because there comes a point when vitamins lose potency. Meaning, the vitamins and minerals will not provide a person with the full nutritional value one expects if they have crossed that threshold.

Interestingly, the form in which vitamins are packaged dictates the rate at which they will lose potency. For instance, tablets and capsules have a longer shelf life compared to chewable gummy vitamins.

To prolong their potency, vitamins should be stored in a cool, dry place. The two most common storage places--the bathroom and the kitchen--are, incidentally, the worst places to keep vitamins. This is so because these places are usually warm and damp, which can accelerate vitamin breakdown, according to CNN.

A better place would be to store vitamin bottles in a closet, or a place in the bedroom away from direct sunlight, according to the outlet.

The dates on the bottle pinpoint the point beyond which the vitamins lose potency. Throwing away vitamins past their "best by" date is a good idea. While they won't make you sick, they also won’t provide you with any benefits.

However, if vitamins become moldy or smelly, discard them at once and get a new bottle. Here, the vitamins can become unsafe for consumption due to contamination.

Having said that, there have been no documented cases where "expired" vitamins have become dangerous to people.

Once you’ve decided to throw the vitamins, simply chucking them in the trash bin is not a good idea.

According to the FDA, the best way to dump the vitamins is by collecting them into a plastic bag and mixing them with an "undesirable substance" like cat litter. Then, seal the mixture and put that bag into the trash.

In other news, pre-diabetic people can turn to vitamin D supplements for help in preventing their condition from progressing to type 2 diabetes, according to a study. “It’s pretty clear vitamin D has a moderate effect on reducing the risk of type 2 diabetes, if you’re at high risk,” lead researcher Dr. Anastassios Pittas, of Tufts Medical Center in Boston, said.