Anise Seed Associated with Improved Quality of Life in Patients with Postprandial Distress Syndrome

Functional dyspepsia (FD) is characterized by early satiety, uncomfortable fullness after eating (postprandial fullness) and moderate to a severe epigastric pain that persists for 12 or more weeks. These symptoms can limit work capacity, generate anxiety, and diminish the overall quality of life (QOL). Medical treatments are limited, with unpleasant side effects, and herbal medicines offer alternative treatment options. In Persian medicine, anise (Pimpinella anisum, Apiaceae) has been traditionally used to reduce gastric distress, inhibit mucosal damage, relieve constipation, and alleviate nausea. FD can be further classified into 2 subtypes—epigastric pain or postprandial distress syndrome (PDS), using the Rome III criteria classification system. FD ranges in prevalence from 10-40% throughout the world, with 3-30% prevalence in Iran.

The authors of this study conducted a double-blind, randomized clinical trial to assess the ability of anise seed to improve the QOL in patients with FD. Using the Rome III criteria for PDS, 180 patients at the Gastrointestinal Clinic of the University Hospital of Isfahan University of Medical Sciences in Alzahra, Iran, were screened for PDS between August 2013 and March 2014 (n=107). Patients were excluded from the study if they had identifiable gastrointestinal symptoms (besides PDS) or were taking prescription and/or herbal medicines. Pregnant/breastfeeding women and individuals with psychological disorders or a history of drug abuse also were excluded.

Patients were randomly assigned into 2 groups. The intervention group (n=47) received anise seed powder (donated by Barij Essence Pharmaceutical Company; Mashhad Ardehal, Iran), and the placebo group (n=60) received corn (Zea mays, Poaceae) starch. All patients were to take 3 g after each meal (3x/day) for a period of 4 weeks. The study notes that both the anise powder and the cornstarch were prepared in similar packages. The method of administration was not provided.

Effectiveness of the treatment (QOL) was evaluated using the Persian (Iranian) Short Form Health Survey (SF-36) questionnaire1 which consists of 36 questions across the following 8 categories: bodily pain (BP), physical functioning (PF), physical role (PR), vitality, general health, mental health (MH), social functioning (SF), and emotional role (ER). Six of these categories were combined into 2 clusters—the physical component summary (PCS [BP, PF, PR]) and the mental component summary (MH, ER, SF).

Scores for the anise group increased in all categories, with the largest improvement in BP (53-point increase) over the placebo group. At baseline, PCS scores were 159 (placebo) and 167 (anise). At week 12, PCS scores were 141 (placebo) and 251 (anise) (P=0.0001). Although 8 patients (n=4, placebo; n=4, anise) were withdrawn from the study, all patients (n=107) were included as an intention-to-treat analysis.

The authors conclude that anise was effective in improving QOL in patients with FD. The authors note that this study was limited by the small sample size, single-center design, and short follow-up period (12 weeks).

The results of this study cannot be generalized to all patients with FD, as the study population was screened only for PDS, a subtype of FD. While the study supports the association of anise seed with an improvement in QOL, specific details regarding dosage administration restrict the reproducibility of the study. Since the Iranian (Persian) translation of the SF-36 has been validated only for large populations,1 this study should be regarded as prospective, given the small sample size and the inclusion of withdrawn patients.


Ghoshegir SA, Mazaheri M, Ghannadi A, et al. Pimpinella anisum in modifying the quality of life in patients with functional dyspepsia: a double-blind randomized clinical trial. J Res Med Sci. December 2014;19(12):1118-1123.