Pharmaceuticals is a ridiculous industry, public health and scientific merit are on the lowest rungs of their list of priorities.
To be honest I can't think of many industries which place public health scientific merit at their top priorities either. You could say the same thing about the food and beverages industries, and Soylent too if you care about mentioning stuff that makes HN tick often.
I don't know what soylent is (beyond just searching it in google). Wikipedia says:
Soylent is a nutritional drink, intended to cover all human nutritional requirements for an adult so that it may serve as main or sole food
There should be a very obvious test for this right? I think a large-scale controlled study would likely show negative effects compared to a randomly sampled population consuming the nutritional equivalent in natural products. This is actually part of the problem - you'll never read about such a study. Why? Because there is no profit incentive for anyone to finance a large-scale study that proves soylent or hypothetical product X to be useless or harmful.
If soylent (or company X) finances a study of their product and the results are contrary to their expectations (assuming the researches are honest and do not engage in fraud) - they can simply shelve that material - and if eventually study i++ is successful they can publish that (without ever referencing any number of past unpublished studies).
The FDA is wasting my money and yours (if you are a US citizen), in a way that normally should address this imbalance of selective interest in research. That it does not - hardly surprises me.