Received: 11 December 2019 | Revised: 15 April 2020 | Accepted: 18 April 2020 DOI: 10.1111/nmo.13874 ORIGINAL ARTICLE The effect of green kiwifruit on gas transit and tolerance in healthy humans Noemi Caballero1,2 | Bouchra Benslaiman1,2 | Juliet Ansell3 | Jordi Serra1,2 1 Motility and Functional Gut Disorders Unit, Centro de Investigación Biomédica en Red Abstract de Enfermedades Hepáticas y Digestivas Background: Green kiwifruit is a fiber-rich fruit that has been shown effective for (CIBERehd), University Hospital Germans Trias i Pujol, Badalona, Spain treatment of constipation. However, fermentation of fibers by colonic bacteria may 2 Department of Medicine, Autonomous worsen commonly associated gas-related abdominal symptoms. Aim: To determine University of Barcelona, Badalona, Spain the effect of green kiwifruit on transit and tolerance to intestinal gas in humans. 3 Zespri International Limited, Mt Maunganui, New Zealand Methods: In 11 healthy individuals, two gas challenge tests were performed (a) after 2 weeks on a low-flatulogenic diet and daily intake of 2 green kiwifruits and (b) after Correspondence Jordi Serra, Gastroenterology Department, 2 weeks on a similar diet without intake of kiwifruits. The gas challenge test con- University Hospital Germans Trias i Pujol, sisted in continuous infusion of a mixture of gases into the jejunum at 12 mL/min for 08916 Badalona, Spain. Email: jserrap.germanstrias@gencat.cat 2 hours while measuring rectal gas evacuation, abdominal symptoms, and abdomi- nal distension. During the 2 weeks prior to each gas challenge test (on-kiwifruit and Funding information Zespri International Limited; Paraguayan off-kiwifruit), the number and consistency of stools, and abdominal symptoms were Government registered. Key Results: Intake of kiwifruits was associated with more bowel movements per day (1.8 ± 0.1 vs 1.5 ± 0.1 off-kiwifruit; P = .001) and somewhat looser stools (Bristol score 3.3 ± 0.2 vs 2.8 ± 0.1 off-kiwifruit; P = .072) without relevant abdominal symptoms. Gas infusion produced similar gas evacuation (1238 ± 254 mL and 1172 ± 290 mL; P = .4355), perception of symptoms (score 1.2 ± 0.2 and 1.3 ± 0.3; P = .2367), and abdominal distension (17 ± 7 mm and 17 ± 6 mm; P = .4704) while on-kiwifruit or off-kiwifruit. Conclusions and Inferences: In healthy subjects, green kiwifruit increases stool fre- quency without relevant effects on intestinal gas transit and tolerance. If confirmed in patients, these fruits may provide a natural and well-tolerated treatment alterna- tive for constipation. KEYWORDS bloating, constipation, intestinal gas, kiwifruit This is an open access article under the terms of the Creat​ive Commo​ns Attri​bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2020 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd Neurogastroenterology & Motility. 2020;32:e13874.  wileyonlinelibrary.com/journal/nmo | 1 of 8 https://doi.org/10.1111/nmo.13874 2 of 8 | CABALLERO et al. 1 | I NTRO D U C TI O N Key Points Kiwifruit is a fruit rich in fibers, C, E, and K vitamins, folate, potassium, • Green kiwifruit is a fiber-rich fruit that has been shown and other phytochemicals that has been shown to have several benefi- to be effective for treatment of constipation in humans. cial effects on gastrointestinal health.1,2 Specifically, kiwifruit has been However, fermentation of fibers by colonic bacteria may shown to accelerate gastric and colonic transit, soften the stools, and worsen commonly associated gas-related abdominal to improve constipation, an effect that can be partially mediated by 3-5 symptoms. the high fiber contents of kiwifruit. Patients with constipation and • In a cross-over, randomized study in healthy subjects, other related functional gut disorders like constipation-predominant intake of green kiwifruit increased bowel movements irritable bowel syndrome often refer gas-related abdominal complains, without effects on gas transit and tolerance in response like bloating and abdominal distension, that in many cases are referred 6,7 to a gas challenge test. as their most bothersome symptoms. Fibers have a high potential • In healthy subjects, the fiber-rich green kiwifruit in- to produce intestinal gas by increasing bacterial fermentation in the creases stool frequency without relevant effects on colon, and the development of gas-related abdominal symptoms may intestinal gas transit and tolerance. If confirmed in pa- be a limiting factor for prescription and intake of fibers and some laxa- 8-10 tients, these fruits may provide a natural and well-toler- tives like lactulose that are fermented by colonic bacteria. ated treatment alternative for constipation. Kiwifruits contain 1.4-3.0 g. of dietary fiber per 100 g. of fruit. One third soluble fiber, mainly pectic polysaccharides, that when reaching the colon should be fermented by colonic bacteria and produce gases and short-chain fatty acids, and two thirds insoluble fiber, mainly cel- the study had been previously approved by the Ethics Committee of lulose and hemicellulose which should not produce any fermentation the University Hospital Germans Trias i Pujol, and all subjects gave 1, 2,11 when reaching the colon. The effect of kiwifruits on gas transit written informed consent before participating in the study. and evacuation is uncertain. Previous studies from other laboratories have shown that psyllium and high-calorie meals delay gas transit and evacuation.12,13 In addition, trapping of gas by viscous material, as has 2.2 | Intervention period 14 been described for water after intake of a similar quantity of kiwifruit, could delay gas transit and produce gas-related abdominal symptoms. Two weeks before the gas challenge test (see below), participants On the other hand, a prokinetic effect of kiwifruit5 could accelerate were instructed to follow a low-flatulogenic diet excluding legumes, transit and removal of intestinal gas, and thereby prevent gas-related vegetables, garlic, onion, cucumber, nuts, cereals, whole-meal bread, abdominal symptoms while improving constipation. and fizzy drinks. In random order, participants were assigned to eat The aim of the present study was to determine the effect of green 2 green kiwifruits without skins every morning (Zespri International, kiwifruits on transit and tolerance to intestinal gas in healthy subjects. approximate weight 150 g per kiwifruit), or to follow the same low- Using a previously developed and validated method of intestinal gas flatulogenic diet but with no intake of kiwifruits. 15-18 challenge, we developed a randomized, cross-over study compar- During the 2-week intervention periods, participants filled a ing, on separate days, the responses to a gas challenge test performed diary recording in separate questionnaires the number and type, after a 14-day low-flatulogenic diet including intake of two green kiwi- according to the Bristol stool form scale, of bowel movements, the fruits per day, or after a 14-day low-flatulogenic diet without intake of intensity of abdominal pain and the intensity of abdominal bloating, kiwifruit. Due to the rapid normal transit of gas in healthy subjects, a both using 0-3 score scales were 0 was no sensation, 1 mild sensa- concomitant lipid infusion into the proximal duodenum, mimicking the tion, 2 moderate sensation and 3 severe sensation. In addition, the physiological postprandial caloric load, was perfused during gas infu- number of kiwifruit ingested was registered. sion to delay intestinal transit of gas, as used in previous studies.16,19,20 2.3 | Gas challenge test 2 | M ATE R I A L A N D M E TH O DS The gas challenge test was performed using a methodology that has 2.1 | Participants been extensively used and validated in detail.15-18,21-24 Eleven healthy individuals (8 women and 3 men; age range 18-23 years) without gastrointestinal symptoms participated in the 2.3.1 | Jejunal gas infusion study. Subjects completed a pre-entry questionnaire to determine the absence of gastrointestinal symptoms, including abdominal pain, Gas was continuously infused into the proximal jejunum at 12 mL/ dyspepsia, bloating, constipation, diarrhea, feeling of excessive ab- min via an oro-intestinal polyvinyl tube (3.2-mm external diam- dominal gas, excessive gas evacuation, or belching. The protocol for eter; 1.6-mm internal diameter) connected to a volumetric pump CABALLERO et al. | 3 of 8 (GIP-3000 Infusion Pump, Soifer Solucions SL). The gas mixture 2.3.5 | Abdominal distension infused contained 88% nitrogen, 6.5% carbon dioxide, and 5.5% oxygen mimicking the partial pressures of venous blood gases to Once the subjects were positioned in bed (Section 2.3.6), a non-stretch minimize diffusion across the intestine-blood barrier. 48-mm wide belt with a metric tape measure was adjusted around the abdomen over the umbilicus by means of two elastic bands. Girth measurements were taken at 10-minute intervals, while the subjects 2.3.2 | Measurement of rectal gas evacuation were breathing relaxedly, as the average of inspiratory and expiratory determinations over three consecutive respiratory excursions. Intestinal gas evacuation was collected via an intrarectal Foley cath- eter (20 French; Bard) with the balloon inflated with 5 mL of water. The catheter was connected to a leak-proof, low-resistance collec- 2.3.6 | Procedure tion line, using a barostat, and the volume continuously recorded on a personal computer, as previously described. After the 2-week intervention period (see above), participants were instructed to have a light dinner the night before the gas challenge test, that consisted of meat, fish, eggs, rice, pasta, and/or white bread, 2.3.3 | Lipid infusion but avoiding dairy products, salad, fruit, and alcoholic beverages. On the day of the study, participants were orally intubated after an ® A mixture of lipids (Intralipid 20%; Pharmacia & Upjohn, St Cugat 8-hour fast. No kiwifruit was eaten the day of the study. The intestinal del Vallés) diluted in saline was infused into the duodenum at 1 mL/ tube assembly was positioned under fluoroscopic control with the gas min (1 Kcal/min) using a volumetric pump (Alaris GH Plus Guardrails; infusion port 5 cm caudad to the angle of Treitz. The rectal cannula CareFusion). Lipids were infused via a 1.2 mm ID channel added to was introduced, and the subjects were then placed supine in bed at an the intestinal tube assembly, with its distal port located in the duo- angle of 30° to the horizontal. The studies were conducted in a quiet, denum 15 cm orad to the gas infusion site. isolated room. The tubes were connected to the infusion and collec- tion systems, and gas transit was continuously recorded while percep- tion and abdominal girth were measured at 10-minute intervals. 2.3.4 | Intestinal gas tolerance Conscious perception was measured at 10-minute intervals by 2.4 | Experimental design means of four graphic rating scales, each graded from 0 (no percep- tion) to 6 (painful sensation), specifically for scoring four possible A two-period, cross-over, randomized, single-blind study was de- types of abdominal sensations: (a) pressure/bloating, (b) cramp/rum- signed to determine the effect of green kiwifruit intake on gas tran- bling sensation, (c) puncture/stinging sensation, and (d) other type of sit and tolerance (Figure 1). In each participant, two gas challenge sensation (to be specified), respectively. The questionnaire included tests were performed with a 4-week interval. Gas challenge tests an additional tic box (YES/NO) to signal belching. The location of the were preceded by a 2-week intervention period with the subjects perceived sensations was marked on an abdominal diagram divided on a low-flatulogenic diet with or without daily intake of 2 green ki- into 9 regions corresponding to epigastrium, periumbilical area, hy- wifruits. After a 2-week washout period, a new 2-week intervention pogastrium, both hypochondria, flanks, and iliac fossae. Participants period started and the second gas challenge test was performed. were instructed to report the sensations perceived over the preced- The gas challenge tests were performed with the investigator blind ing 10-minute period in the scales. for the assigned intervention. F I G U R E 1 Experimental design. In each participant, two gas challenge tests were performed after 2 wk on-kiwifruit and off-kiwifruit using a randomized cross-over design. While on-kiwifruit, last kiwifruit intake occurred 24 h, before the gas challenge test 4 of 8 | CABALLERO et al. F I G U R E 2 Form of stools according to the Bristol Stool Form Scale during 2-wk low flatulogenic diet on-kiwifruit (intake of 2 pieces of green kiwifruit per day) and off-kiwifruit. Note that the predominant stool form moved from type 3 while off- kiwifruit to type 4 on-kiwifruit, reflecting a looser consistency of stools, but within the normal range of stool form 2.5 | Data analysis 3 | R E S U LT S In each subject, the number and type of bowel movements, and the 3.1 | General aspects intensity of perception during each 2-week intervention periods were registered for future comparisons. During each gas challenge test, in- Eleven healthy subjects (8 women and 3 men; age range 18-23 yrs) testinal gas transit was evaluated by the volume of gas retained within were included in the study. All the subjects completed the 2-week the gut (volume infused minus volume collected) at different intervals intervention period uneventfully. All subjects scored intake of two during the study. Perception was measured by the score rated in the kiwifruits, or 0 kiwifruits, as corresponded, during the 14 days prior scales; the highest score (the most severe sensation independently of to each gas challenge test. All participants but one completed the 2 the type), instead of the mean or cumulative scores, was computed for gas challenge test procedures as planned, so finally, the results of 10 comparisons. In each subject, we also counted the number of times healthy subjects who completed the study could be analyzed. The each abdominal sensation was scored in the repeat measurements reason for withdrawal of one healthy subject was a technical problem during the study to calculate the frequency (as percent distribution) with the gas-recovery system that did not allow measurement of gas of each specific sensation. In the anatomical questionnaire, we cal- evacuation during the second gas transit procedure. All the remain- culated the percentage of sensations referred over each abdominal ing 10 participants completed the study without remarkable events. region, as well as the percentage referred over more than one region. Changes in abdominal girth during the study were referenced to girth measurement at the start of the study, that is before gas infusion was 3.2 | Effects of kiwifruit on abdominal symptoms, started. stool consistency, and frequency Kiwifruit intake during the 2 weeks preceding the gas transit proce- 2.6 | Statistical analysis dure was well-tolerated by all the subjects and induced neither ab- dominal pain (score 0.1 ± 0.1) nor bloating (score 0.1 ± 0.0). Similarly, Based on previous studies performed using an identical methodol- during the 2 weeks off-kiwifruit no relevant abdominal symptoms ogy in healthy subjects,15-17 we calculated that a sample size of 10 were rated (pain score 0.0 ± 0.0; bloating score 0.1 ± 0.0). The num- subjects per group could discriminate differences in gas retention ber of bowel movements was somewhat, but significantly greater with a power of 80% and an alpha error of 5%. when participants were on a diet including intake of 2 green kiwi- In each treatment period, mean values (±SE) of the parameters fruits per day (1.8 ± 0.1 stools/d), than during the 2 weeks off-ki- measured were calculated. The Kolmogorov-Smirnov test was used wifruit (1.5 ± 0.1 stools/d; P = .001). The consistency of the stools to check the normality of data distribution. Comparisons of para- measured by the Bristol Stool Form Scale tended to be softer while metric, normally distributed data were performed by the Student t on-kiwifruit (Figure 2). The predominant stool form off-kiwifruit test for paired data. Non-parametric data were compared using the was Bristol 3, whereas the predominant stool form on-kiwifruit Wilcoxon signed-rank test. was Bristol 4, but these differences were minor and did not reach CABALLERO et al. | 5 of 8 F I G U R E 3 Responses to a gas challenge test (infusion of gas into the jejunum al 12 mL/min for 120 min) performed after 2 wk on a low- flatulogenic diet on-kiwifruit (intake of 2 pieces of green kiwifruit per day) and off-kiwifruit. Observe that there were no differences in rectal gas evacuation, perception of abdominal symptoms or objective abdominal distension in the studies performed on-kiwifruit and off- kiwifruit statistical significance (P = .068). Hence, most stools lied within the of the infusion period, participants had retained 206 ± 280 mL after normality range (Bristol score 3-5), and only one subject while on-ki- 2 weeks off-kiwifruit, and 123 ± 250 mL of gas when gas infusion wifruit and one subject while off-kiwifruit referred some loose stools was performed after 2 weeks on-kiwifruit (P = .417). (Bristol 6 or 7) during the intervention period (P = .655). 3.4 | Effect of kiwifruit on abdominal symptoms 3.3 | Effect of kiwifruit on gas transit during the gas during the gas challenge test challenge test Gas infusion was well-tolerated by all the subjects and produced a Gas infusion produced a continuous evacuation of gas from the mild increment in abdominal perception during the first 60 minutes rectum, without any differences whether gas infusion was per- of infusion, that was then maintained until the end of the study, formed after 2 weeks daily kiwifruit intake or not (Figure 3). Hence, without differences whether the gas transit studies were performed after an initial lag time that resulted in a maximal gas retention of off-kiwifruit or on-kiwifruit (Figure 3). Hence, mean perception score 340 ± 122 and 334 ± 104 mL after 70 minutes of gas infusion (stud- was 1.3 ± 0.8 off-kiwifruit and 1.2 ± 0.2 on-kiwifruit (P = .4733). ies off-kiwifruit and on-kiwifruit, respectively; P = .484), at the end When individual data were analyzed, no subject referred discomfort 6 of 8 | CABALLERO et al. (score 5) and only 3 subjects developed moderate perception (score improve constipation in clinical trials, containing 9 g of dietary fibers. 3 or 4) at the end of the gas challenge test in the studies performed Despite its potential gas production, during the 2 weeks kiwifruit off-kiwifruit. intake participants did not complain of any gas-related abdominal The predominant symptoms referred during the gas challenge symptoms, and when a gas infusion test was performed, the volume test were pressure/bloating and cramp/rumbling sensation, mainly of gas expelled was similar whether the subject had been on-kiwi- referred over the abdominal midline, without differences whether fruit or off-kiwifruit during the 2 weeks prior the gas infusion test. the test was performed on-kiwifruit or off-kiwifruit (data not shown). Previous studies have shown that the increase in gas production in- duced by fibers depends on the type of fibers ingested. Hence, Levitt et al36 compared the effect of lactulose, the poorly fermentable fiber 3.5 | Effect of kiwifruit on objective abdominal psyllium, and the non-fermentable fiber methylcellulose on flatus distension during the gas challenge test production in healthy subjects, and found that whereas lactulose increased flatus production significantly, none of the fibers tested Before the start of the gas infusion procedure, at arrival to the lab- induced any increment in flatus production. Likewise, Gonlachanvit oratory, we found no differences in abdominal girth whether the et al1 using a similar gas infusion technique as we used in the present subjects had been eating 2 green kiwifruits per day during 14 days study found that psyllium consumption delayed gas transit without (abdominal girth 79.2 ± 3.7 cm) or were not eating kiwifruit (abdomi- any associated increment in gas evacuation. In a randomized clinical nal girth 79,7 ± 3.7 cm: P = .3058). Gas infusion was associated with a trial comparing the effect of psyllium vs a mixture of soluble and minor increment in abdominal girth during the first 60 minutes of gas insoluble fibers in patients with constipation, gas-related abdominal infusion, that was then maintained until the end of the study, with- symptoms improved most when the mixed fibers were consumed.37 out differences whether the gas transit studies were performed on- Hence, these data may suggest that a delay in gas transit induced by kiwifruit or off-kiwifruit (Figure 3). Hence, final abdominal distension some fibers could worsen abdominal symptoms like bloating. In our was 1.7 ± 0.6 cm off-kiwifruit and 1.7 ± 0.7 on-kiwifruit (P = .4704). study using kiwifruit, a mixture of soluble and insoluble fibers, no delay in gaseous transit time was observed after kiwifruit ingestion. Previous studies using radiopaque markers have shown that green 4 | D I S CU S S I O N kiwifruit accelerates whole gut transit time in patients with consti- pation and constipation-predominant irritable bowel syndrome. 2-4 In the present study performed in healthy subjects, we have shown In a recent study from Nottingham using MRI in healthy subjects, that daily intake of two green kiwifruits per day increases stool fre- the authors found that ingestion of two green kiwifruits per day, the quency and soften the stools without inducing gas-related abdomi- same intake as we used in the present study, produced an increment nal symptoms, without increasing rectal gas evacuation, and without in water content in the small bowel and the ascending colon that effects on gas transit and tolerance to intestinal gas loads. could account for the increment in stool frequency and looser stool In patients with constipation, increased dietary fibers are con- consistency observed.14 However, in this study, the authors found sidered first-line treatment in most of the published guidelines on the increment in colonic contents induced by kiwifruit, smaller than chronic constipation and constipation associated with irritable bowel the increment induced by intake of psyllium in previous studies. syndrome. 25-29 However, patients with constipation often complain Hence, kiwifruit induced a rise in the colon volume by 16% whereas of associated symptoms like bloating and abdominal distension, psyllium produced a 50% increment. The authors conclude that ki- which may worsen after fiber consumption due to the increased wifruits have prokinetic effects in addition to water trapping, leading intestinal water and gas volumes induced by fermentation of the to less colonic distension. Taking together the results of these stud- complex polysaccharides that are components of natural fibers.9,30 ies, it seems plausible that a prokinetic effect of kiwifruit, maybe Already in 1969, Steggerda described an increment in flatus produc- associated with the mixed type of fiber contents, could lead to lower tion following consumption of pinto beans,31 and several studies water and gas retention into the colon, and result in lower bloating 32,33 published the following years confirmed these observations. and abdominal distension than other dietary fibers or fermentable In patients with functional gut disorders, increased colonic con- carbohydrates. tents may induce bloating and distension by several mechanisms, In addition to flatus production, another mechanism that reduces including visceral hypersensitivity,34 altered transit and evacuation intestinal gases is diffusion of gases to the bloodstream.8 Bacterial of gas,18 and altered viscero-somatic reflex responses with abdomi- fermentation produces different gases, mainly H2, CH4, and CO2. no-phrenic dysfunction.35 When in the intestinal lumen, these gases are partially absorbed to Among the aliments that may be useful for the first-line manage- the bloodstream. Diffusion of gases depends on the pressure gra- ment of constipation, green kiwifruit is a fiber-rich fruit that has been dient across the intestinal/blood barrier and the solubility in lipids 2,3 shown to relief constipation in different clinical trials. As most nat- of each specific gas.8,38 By contrast to nitrogen, which has a poor ural aliments, kiwifruit contains a mixture of soluble and non-soluble diffusivity, gases produced during fermentation diffuse easily to fibers. Specifically, in the present study, the subjects consumed 2 the bloodstream. It has been calculated that about 2/3 of the H2 green kiwifruits per day, a number of fruits that have been shown to produced during bacterial fermentation is absorbed under basal CABALLERO et al. | 7 of 8 conditions.32 Hence, a part of gases produced after kiwifruit intake was supported by a Grant from the Paraguayan Government can also be cleared from the intestine by this mechanism. However, (Programa Nacional de Becas de Postgrado en el Exterior—Don gas infusion as was performed in the present study produces a wash- Carlos Antonio López, Fondo para la Excelencia en la Educación y la out effect of intestinal gases that should lead to increased rectal gas Investigación N° 19/2015). evacuation during the gas infusion procedure if a significant volume of gas was produced during kiwifruit intake.17,33 Hence, even though C O N FL I C T O F I N T E R E S T no measurement of exhaled gas was performed in our study, our re- This work has been performed as part of the doctoral thesis in medi- sults suggest that the volume of intestinal gases produced during cine of Dr Caballero at the Autonomous University of Barcelona. Dr kiwifruit intake is small, and of low clinical significance for develop- Serra has received research funds from Salvat, Zespri, and Bayer and ment of gas-related symptoms. acted as consulter/speaker for AB-biotics, Allergan, Bayer, Norgine, The data of our study apply for healthy subjects with normal Cassen-Recordati, Zespri, and Reckitt Benkiser. Juliet Ansell is en- bowel habits. Further studies are necessary to determine the effects ployed by Zespri. Noemi Caballero and Bouchra Benslaiman have of kiwifruits on transit and tolerance of intestinal gas in patients with nothing to disclouse. constipation. Previous studies have shown that patients with irrita- ble bowel syndrome and abdominal bloating have a delayed transit AU T H O R C O N T R I B U T I O N S of intestinal gas that is associated with abdominal symptoms.16,18 In NC involved in acquisition of data, analysis and interpretation of addition, these patients may be more sensitive to distension than data, drafting of the manuscript, and statistical analysis; BB was healthy controls and so may tolerate kiwifruit less well as is true Nurse coordinator and involved in recruitment of volunteers and ac- of fructose and fructans.39 Hence, we cannot ascertain that even quisition of data; JA involved in study concept and design, obtained small volumes of gas produced during kiwifruit intake could lead to funding; JS involved in study concept and design, analysis and inter- gas retention and gas-related abdominal symptoms in these specific pretation of data, critical revision of the manuscript for important patients. intellectual content, statistical analysis, and obtained funding. In the present study, the quantity of fermentable fiber con- tained in the kiwifruits administered during the study was smaller ORCID than the quantity of fibers administered in other studies using Jordi Serra https://orcid.org/0000-0003-2120-6270 for example psyllium. This relatively small volume was chosen because this is the recommended for treatment of constipation, REFERENCES and reflects the clinical consequences of treatment with kiwifruit. 1. Richardson DP, Ansell J, Drummond LN. The nutritional and health But we cannot exclude that intake of greater number of kiwifruits, attributes of kiwifruit: a review. Eur J Nutr. 2018;57(8):2659-2676. 2. Boland M, Moughan PJ. Advances in Food and Nutrition Research. and thereby a greater quantity of fibers, could produce different Volume 68. Nutritional Benefits of Kiwifruit. Vol. 1st ed. Waltham, gas-related responses, as previously described for other type of MA: Elsevier Inc.; 2013. fibers.1 3. Chan AOO, Leung G, Tong T, Wong NYH. 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