A Dose-Escalation Study for Identifying Safe Doses of Coffee Cherry Pulp Juice Concentrate in Healthy Subjects

Abstract

Previously viewed as industrial waste in coffee manufacture, coffee cherry pulp now receives attention as a functional food with potential health benefits. However, the maximum safe dose of this novel ingredient for human consumption was unknown. This dose-escalation study aimed to evaluate the safety and tolerability of coffee cherry pulp juice concentrate in healthy subjects and identify the maximum tolerated dose (MTD). In the single ascending dose phase, six participants received a single dose daily in a stepwise escalation from 1 to 14 g of coffee cherry pulp juice concentrate (50 ̊Brix), within 14 days. In the multiple ascending dose phase, twelve subjects received a stepwise escalating dose from 1 to 14 g of coffee cherry pulp juice concentrate twice daily (2-28 g per day). Each dose has been repeated for two weeks. Safety and tolerability were assessed by subject diaries and clinical laboratory tests. The results show no adverse events occurred after single or repeated doses. The average blood biochemical values are all in the normal range throughout the study. The maximum tolerated dose of coffee cherry pulp juice concentrate in short term is 14 g twice daily, which equals 28 g per day (total solid of 14 g). Future studies for the long-term safety of coffee cherry pulp juice concentrate are warranted.