Dietary selection is important to assure the balance of nutrients for energy, growth, maintenance, and reproduction. The innate response of an animal is to avoid eating plants with toxic secondary metabolites, but these properties can be medicinal when ingested in appropriate amounts. It is proposed that under physical conditions that require direct intervention (health maintenance or self-medication), animals ingest even such toxic plants for their medicinal benefits to regain health homeostasis. Previous studies on primate plant food selection have found that 15~25% of the items in their diet could be classified as ‘medicinal food’ (plants with bioactive, physiology modifying properties). Here we focus on identifying prospective medicinal foods in the diet, in order to investigate the potential properties and possible roles of such items for a wild group of Tibetan macaques (Macaca thibetana) at Mt. Huangshan, Anhui Province, China. Using a 50 species food list of this group, a pharmacological database search was conducted. We identified 12 species (24%) with significant pharmacological potential. Across the 12-month study, medicinal foods accounted for 18~23% of the total diet in any one season. The reported activities in these items included anti-parasitic, anti-bacterial, anti-rheumatic, neuroprotective, osteoprotective, reproductive stimulant and wound healing, among others. While the actual medicinal benefits to macaques gained from ingesting these plants are yet unknown, based on the available evidence for their parasite infection ecology, reproductive behavior and possible stress reduction, we hypothesize on the possible scope of self-medication in Tibetan macaques, and suggest future avenues for research.
