"This isn't just water like we drink. It's full of nutrients and chemicals, as well as tiny animals like phytoplankton frozen inside," Ms Taylor says.

Sugar provides quick energy and nutrient absorption power.

“If finalized, the proposal would give consumers readily visible information about a food’s saturated fat, sodium and added sugars content — three nutrients directly linked with chronic diseases when consumed in excess,” the FDA explained.

Round-the-clock renewable energy, plus a stream of CO2, and nutrients with a low carbon footprint, are needed to ensure the setup is climate-friendly, and he thinks that isn’t easily replicated.

In particular, not getting enough of three essential nutrients — vitamin D, vitamin B12 and omega-3 fatty acids — is linked to low energy levels.