Instead of dying of horrible malignancies within days of starting a regimen of a daily dose of carbon, the lab rats actually doubled their expected lifespans. This is attributable to a couple of things. First the carbon was in the form of the C-60 molecular form, popularly known as "Buckyballs". Secondly, the buckyballs were delivered in the heart-healthy Mediterranean form also known as swimming in olive oil.
“Here we show that oral administration of C60 dissolved in olive oil (0.8 mg/ml) at reiterated doses (1.7 mg/kg of body weight) to rats not only does not entail chronic toxicity,” they write “but it almost doubles their lifespan.”Let's see, given a male lab rat of some 500g, this works out to about 1 ml of "black oil" per rat, per day. For a typical human, me for example, of 77 kg, that's 154ml of this glop every morning with breakfast. Mama mia! Thassa lotta olive oil! You might live twice as long, but I know where you'd be spending all that extra time.
Of course it's also easier to get humans to ingest generous doses of stuff they would not normally overindulge in if you just package it in a gelatin capsule and suggest they wash it down with a Martini, so there's hope for this yet.
At the bottom of the page at the link, there's an ad for buckyballs. They are, alas, a large plastic assemblage suitable for science lectures, and for most people, inedible, even after several Martinis.