Understanding the human body is a team effort. That's where the Yachtel group comes in.

Researchers at Yachtolt have been delving into the secrets of probiotics for 90 years.

Yacold also partners with nature portfolio to advance gut microbiome science through the global grants for gut health, an investigator-led research program.

To learn more about Yachtolt, visit yawcp.co.j.jok-u-t-co.j-J-P. That's Y-A-K-U-L-T-O-J-P.

When it comes to a guide for your gut, count on Yacolt.

This is Scientific American's 60-second science. I'm Christopher in Taliatta.

Kristen Choi was scrolling through Instagram this summer when she came across an ad.

I happened to get an Instagram ad one day for the Pfizer trial.

The Pfizer trial for the COVID-19 vaccine.

And it just occurred to me that it was really important for people to volunteer to build the science for these vaccines.

Choi is a nurse and researcher at UCLA. She filled out a form to apply, and in August, she got the first

shot. I had a long study visit with, you know, a physical exam, a number of blood tests and other

tests, a coronavirus test, to make sure that I was healthy and able to participate. And then I got the injection

that same day. That first shot didn't seem that unusual, she says, a little soreness in her

arm. She didn't know whether she'd gotten the real thing or just a placebo. A month later,

she went in for round two. The second shot, though, came with a lot more symptoms than I had ever

experienced with another vaccine. I developed chills, nausea, with a lot more symptoms than I had ever experienced with another vaccine.

I developed chills, nausea, and a headache, fatigue a few hours after the vaccine.

I was feeling pretty sick that day. I went to bed early and woke up in the middle of the night

with a fever. The next morning, her fever spiked to nearly 105. Her symptoms matched the side

effects of the real vaccine,

leading her to believe she'd gotten the real thing. Later that day, her symptoms subsided,

...