Association Between Traditional Herbal Diet and Nasopharyngeal Carcinoma Risk: A Prospective Cohort Study in Southern China

Introduction

Prospective evidence for herbal diet and nasopharyngeal carcinoma (NPC) development is absent. We therefore evaluated the associations of herbal soup and herbal tea with NPC in a prospective cohort study in southern China.

Methods

Based on an NPC screening cohort established in 2008-2015, information on herbal diet consumption, potential confounding factors, and Epstein-Barr virus (EBV) antibody levels were collected from 10,179 individuals aged 30-69 years in Sihui city, southern China. Cox regression models were performed to examine herbal diet with NPC risk, and logistic regression models were used to examine herbal diet with EBV reactivation.

Results

During a median of 7.54 years of follow-up, 69 participants developed NPC. Herbal soup consumption was associated with decreased NPC risk, with HRs of 0.31 (95% confidence interval (CI): 0.15-0.62) for the highest intake frequency and 0.29 (95% CI: 0.16-0.51) for a longer duration. However, herbal tea was not significantly associated. Moreover, we identified herbal soup was inversely associated with EBV seropositivity among all the participants at baseline, with the adjusted ORs being 0.78 (95% CI: 0.65-0.93) for immunoglobulin A antibodies against EBV capsid antigens (VCA-IgA) and 0.76 (95% CI: 0.64-0.91) for nuclear antigen 1 (EBNA1-IgA) in those with the highest frequency and 0.70 (95% CI: 0.59-0.84) for VCA-IgA and 0.64 (95% CI: 0.54-0.77) for EBNA1-IgA in those with the longer duration. Inverse associations were also observed in non-NPC individuals.

Conclusions

With inhibition of EBV reactivation by plants, herbal soup could significantly decrease the risk of NPC in endemic areas.

Chinese nonmedicinal herbal diet and risk of nasopharyngeal carcinoma: A population-based case-control study

BACKGROUND

An association between a nonmedicinal herbal diet and nasopharyngeal carcinoma (NPC) has often been hypothesized but never thoroughly investigated.

METHODS

This study enrolled a total of 2469 patients with incident NPC and 2559 population controls from parts of Guangdong and Guangxi Provinces in southern China between 2010 and 2014. Questionnaire information was collected on the intake of traditional herbal tea and herbal soup as well as the specific herbal plants used in soups and other potentially confounding lifestyle factors. Multivariate logistic regression models were used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the NPC risk in association with herbal tea and soup intake.

RESULTS

Ever consumption of herbal tea was not associated with NPC risk (OR, 1.03; 95% CI, 0.91-1.17). An inverse association was observed for NPC among ever drinkers of herbal soup (OR, 0.78; 95% CI, 0.67-0.90) but without any monotonic trend with an increasing frequency or duration of herbal soup consumption. Inverse associations with NPC risk were detected with 9 herbal plants used in herbal soup, including Ziziphus jujuba, Fructus lycii, Codonopsis pilosula, Astragalus membranaceus, Semen coicis, Smilax glabra, Phaseolus calcaratus, Morinda officinalis, and Atractylodes macrocephala (OR range, 0.31-0.79).

CONCLUSIONS

Consuming herbal soups including specific plants, but not herbal tea, was inversely associated with NPC. If replicated, these results might provide potential for NPC prevention in endemic areas.