At room temperature, the exothermic polymerization (-136 kJ mol -1 ) yields a product (C3O2)n of well-defined stoichiometry, that when heated, releases carbon monoxide and dioxide leaving a graphite-like carbon with low oxygen content. Over the last century, many different structures have been suggested, from a spyrocyclobutadione, to poly-αand -γ-pyrone and cyclopolycarbonsuboxide. Often forgotten in previous reports are the biological and biochemical roles and investigations of red carbon, addressed especially by Kerek et al., at the beginning of the 2000s. In these reports, they studied natural sodium and potassium pump inhibiting factors from plant and bacterial sources and found out that natural macroring derivatives of carbon suboxide may have a primary role for efficacious therapeutic approaches against autoimmune, cardiovascular and metabolic diseases. These biological macrorings constituted of 6 to 12 units were in equilibrium between the lipophilic cyclopyrone and hydrated geminal-diol form, accompanied by significant decrease in the visible absorption, from brown to transparent.