You either needed to read more or more closely. According to wikipedia linked:
"Like other food substances, dietary supplements are not subject to the safety and efficacy testing requirements imposed on drugs, and unlike drugs they do not require prior approval by the FDA; however, they are subject to the FDA regulations regarding adulteration and misbranding. The FDA can take action against dietary supplements only after they are proven to be unsafe. "
No, you need to read more closely. It says exactly what I said. Soylent is covered under the exact same requirements as all other foods. This is very simple to understand, and I honestly can't imagine how you can possibly be having difficulty with this.
>The Dietary Supplement Health and Education Act of 1994 mandated that the FDA regulate dietary supplements as foods
Soylent has to adhere to the exact same standards as all the other food you buy right now.