eli5: How does Dietary Reference Intake work?



Hi all,

so I wonder what happens if I dont get my recommended intake of e.g. Vitamine A? I guess I don’t need it *really* daily and the recommendation are more of a guideline regarding a average you should get in a week. But maybe I am wrong? Can I eat something with a lot of Vitamine A and skip some days? How many days until it becomes a problem? What with the other stuff?

And also how did scientists get these measurements? Did they withheld rats selected nutrients and watched how long till they died and then scaled those nutrients to human levels or something like that?

In: Biology

It depends on the vitamin, and on the individual. Certain vitamins, like A and B12, are so critical that the body keeps reserves sufficient for years without intake. Other less important nutrients might have little to no reserves and require frequent dietary intake.

The dietary intake can be thought of as the minimum safe amount that a roughly average human needs to consume to comfortably avoid deficiency. Since the daily amounts of many vitamins and nutrients are in the microgram amount, it’s fairly easy to remain above those intake amounts, even if you skip a day or two.