Carrieri et al observe that chocolate abstainers, among those with HIV-HCV coinfection, are more likely to become depressed. This underscores 2 important issues: abstainer effects and effect modification (“confection vs coinfection”).
Persons who abstain from chocolate may do so for a reason. This reason, rather than lack of chocolate, may relate to higher depression risk. For instance, those who forswear chocolate because of caffeine (or methylxanthine) intolerance may also renounce coffee and lose the marked liver protections coffee purportedly affords.1 This may hasten liver compromise in HCV, itself linked to depression,2 and may increase prospects of HCV treatment,3 typically interferon alfa, for which depression is a well-recognized adverse effect.4 (This may also increase vulnerability to hepatically cleared drugs and chemicals, some with depressogenic effects such as alcohol, which is an issue in this HCV population.)
Golomb BA, Koperski S, Rose N. Chocolate Consumption and Effects on Serotonin Synthesis—Reply. Arch Intern Med. 2010;170(17):1608–1609. doi:10.1001/archinternmed.2010.332