Romans did eat human meat sometimes through medicinal cannibalism.
When Romans ate human meat through medicinal cannibalism, they did so for eating the body parts and blood for healing purposes.
In extreme circumstances, Romans would also sometimes eat human meat through survival cannibalism such as during sieges, although it was often viewed with horror and sometimes would be used as a smear tactic against enemies.
Also Ancient Roman authors also documented such practices of eating human meat, with Pliny the Elder detailing the medicinal uses for human organs and blood.
Romans who were influences by Greek texts, used various different human body parts, which included the brain, bone marrow and blood for medicinal purposes.
And fresh human blood, especially from wounded gladiators was also believed to cure ailments such as epilepsy.
Medical vampirism is also a term that describes the practice of consuming of human blood for it's purported healing properties.
And instances of cannibalism during Roman times occurred during sieges, like the siege of Numantia in 134 BCE and the First Mithridatic War at Athens, when people resorted to eating of human bodies to survive starvation.