One in six Americans get food poisoning every year, and those sicknesses can be deadly. In order to protect consumers, there are several checks and balances in place — among them, scientists who test random samples of food products sold in the US to make sure they're safe to eat.

So what's it like to be one of those scientists? And how does this work change your perceptions of food?

This week, Cynthia Mangione, a food laboratory specialist at the New York State Department of Agriculture and Markets, and Stephanie Brock, a radiation health supervisor at the Kentucky Department for Public Health, took to Reddit to answer questions about their jobs. They spend their days "testing products imported into the US for dangerous pathogens, as well as illegal dyes, metals, antibiotics and more." Here are the three most surprising reveals:

1) They've found lead, arsenic, and mercury in imported spices and in dietary supplements

One of the things we test for is illegal dyes or metals in spices. We've found lead, for example. Or spices that have been replaced with fillers like peanut cake. It's actually a significant issue in spice manufacturing. American spice companies have been very interested in our findings because they don't want this stuff in the marketplace either.

They also wrote: "We often find dangerous levels of arsenic, lead and mercury in medical supplements."

Unfortunately, supplements are barely regulated in the United States. The makers of these pills — which are commonly sold at pharmacies, natural health stores, and gyms — don't need to prove their products are safe or even effective before putting them on store shelves.

That fact that prompted Vox's Soo Oh and me to comb through government databases, court documents, and scientific studies to find out what dubious ingredients have been found lurking in popular supplements. We uncovered more than 850 products that have contained illegal and/or hidden ingredients — including banned drugs, pharmaceuticals like antidepressants, and other synthetic chemicals that have never been tested on humans.

2) The one food safety testers avoid eating: sprouts

I have given up sprouts because of ongoing concerns with their safety. We also make sure to wash ready-to-eat veggies (despite the "triple wash" designation).

According to the Food and Drug Administration's food safety website, sprouts — such as alfalfa, clover, radish, and mung bean sprouts — are a higher-risk food. This is because they are eaten raw and, unlike other fresh produce, need to grow in warm and humid environments — the ideal breeding grounds for dangerous bacteria such as salmonella, listeria, and E. coli. Washing them doesn't always kill that potentially harmful bacteria.

Since 1996, there have been more than 30 outbreaks in the US associated with sprouts. In a recent analysis of food outbreaks in the US, sprouts were among the leading culprits.

3) The craziest thing they found in a food they tested…

We recently found a whole mouse in an energy drink!

Can't really explain this one, but it's pretty disturbing.

One big unanswered question

The one thing on many redditors' minds was whether there are particular companies or countries that were more often guilty of manufacturing or importing contaminated food products. The food scientists wouldn't dish, saying they weren't prepared to name names. But you can search for some of that information on an FDA website. The data is fascinating. Or, as one redditor put it, "A faith sucking rabbit hole."