Gold kiwifruit consumption and increased vitamin C intake have been associated with improved mood, vitality, and wellbeing in healthy individuals(1,2). However, to date, no studies have focussed exclusively on the efficacy of gold kiwifruit for improving such outcomes in participants with disturbed mood. A randomised crossover trial was undertaken to examine the efficacy of ZespriTM SunGoldTM kiwifruit for improving psychological wellbeing and vitamin C concentrations in adults with sub-clinical levels of mood disturbance. In a two-period, non-blinded crossover trial, N = 26 adults aged 21 to 60 years (M = 36.1, SD = 11.0) with mild to moderate mood disturbance were randomised to a counter-balanced sequence. Participants consumed 2x SunGold kiwifruit daily or their typical diet for four weeks, with a two-week washout between periods. The primary outcome was change in mood disturbance, with secondary outcomes including plasma vitamin C, wellbeing, vitality and gut health. Results indicated a significant time x treatment interaction effect for mood disturbance (F(2,107.3) = 6.19, p = ,003) with significant improvements in mood disturbance scores between baseline and post-intervention during the SunGold kiwifruit period. A significant time x treatment interaction effect for blood plasma vitamin C (F(2,98.5) = 3.65, p = ,029) also demonstrated increased vitamin C concentrations during the SunGold kiwifruit period. A significant time x treatment interaction effect for wellbeing (F(2,104.7) = 4.5, p = ,013) was evident with wellbeing significantly improved between baseline and post-intervention during the SunGold kiwifruit period. The time x treatment interaction for vitality approached significance (F(2,104.7) = 2.89, p = ,06) with increases in vitality following SunGold kiwifruit consumption. These results provide preliminary evidence that SunGold kiwifruit consumption improves psychological wellbeing in mood-disturbed adults, which corresponds to increased plasma vitamin C concentrations. Future research is required to replicate this effect and to further demonstrate the potential benefit of whole-food interventions for treating mood-disturbance.

Functional gastrointestinal disorders including constipation affect up to 14 % of the world's population. Treatment is difficult and challenging resulting in a need for alternative safe and effective therapies. The present study investigated whether daily consumption of three gold-fleshed kiwifruit could alleviate constipation and improve gastrointestinal discomfort in mildly constipated individuals with and without pain. A total of thirty-two participants were enrolled in a 16-week randomised, single-blind, crossover study. Participants received either three ‘Zesy002’ kiwifruit or 14·75 g Metamucil® (5 g dietary fibre/d (a positive control)) for 4 weeks each with a 4-week washout between treatments. A 2-week washout period was included at the beginning and end of the study. Daily bowel habit diaries were kept throughout the study. The primary outcome measure was differences in the number of complete spontaneous bowel movements (CSBM). Secondary outcome measures were bowel movement frequency and stool form as well as digestive symptoms and comfort. The number of CSBM per week was significantly greater during daily consumption of three kiwifruit compared with the baseline (6·3 v. 3·3; P < 0·05) and the Metamucil® treatment (6·3 v. 4·5; P < 0·05). Stool consistency was also improved, with kiwifruit producing softer stools and less straining (P < 0·05). Gastrointestinal discomfort was also improved compared with baseline for abdominal pain, constipation and indigestion (P < 0·05) during the kiwifruit intervention and constipation during the Metamucil® intervention (P < 0·05). This randomised controlled trial demonstrates that daily consumption of three gold-fleshed kiwifruit is associated with a significant increase of two CSBM per week and reduction in gastrointestinal discomfort in mildly constipated adults.

This study investigated the impact of ACTAZIN™ green (2400 and 600 mg) and Livaux™ (2400 mg) gold kiwifruit supplements on faecal microbial composition and metabolites in healthy and functionally constipated (FC) participants. The participants were recruited into the healthy group (n 20; one of whom did not complete the study) and the FC group (n 9), each of whom consumed all the treatments and a placebo (isomalt) for 4 weeks in a randomised cross-over design interspersed with 2-week washout periods. Modification of faecal microbiota composition and metabolism was determined by 16S rRNA gene sequencing and GC, and colonic pH was calculated using SmartPill® wireless motility capsules. A total of thirty-two taxa were measured at greater than 1 % abundance in at least one sample, ten of which differed significantly between the baseline healthy and FC groups. Specifically, Bacteroidales and Roseburia spp. were significantly more abundant (P < 0·05) in the healthy group and taxa including Ruminococcaceae, Dorea spp. and Akkermansia spp. were significantly more abundant (P < 0·05) in the FC group. In the FC group, Faecalibacterium prausnitzii abundance significantly increased (P = 0·024) from 3·4 to 7·0 % following Livaux™ supplementation, with eight of the nine participants showing a net increase. Lower proportions of F. prausnitzii are often associated with gastrointestinal disorders. The discovery that Livaux™ supplementation increased F. prausnitzii abundance offers a potential strategy for improving gut microbiota composition, as F. prausnitzii is a butyrate producer and has also been shown to exert anti-inflammatory effects in many studies.

Kiwifruit is a carbohydrate food of low glycaemic potency which could potentially be exchanged for starch-based foods in management of postprandial glycaemia. The effect of equicarbohydrate partial exchange of kiwifruit varieties ‘Hayward’ green (GR) and ‘Zesy002’ (SunGold; SG) for a starchy wheat-based breakfast cereal (WB) on the characteristics of the postprandial glycaemic response and satiety was therefore determined. A total of twenty non-diabetic subjects (mean age 36 years; mean BMI 24·5 kg/m2) consumed four meals, each containing 40 g available carbohydrate, in random order, after an overnight fast. The meals were: (1) glucose; (2) 70·29 g breakfast cereal; (3) 200 g of GR plus breakfast cereal (30·93 g); and (4) 200 g of SG plus breakfast cereal (27·06 g). Throughout the 180 min postprandial period, capillary blood glucose concentrations were monitored, and satiety rated by a visual analogue scale. Partial kiwifruit substitution of WB significantly reduced postprandial glycaemic response amplitude (glucose, 3·91; WB, 3·66; WB + GR, 2·36; WB + SG, 2·31  mmol/l; least significant difference (LSD) 0·64; P < 0·001) and incremental area under the blood glucose response curve (0–120 min) (glucose, 228; WB, 180; WB + GR, 133; WB + SG, 134 mmol/l × min; LSD 22·7; P < 0·001). The area between baseline and response remained positive in kiwifruit-substituted meals but became negative after 120 min with glucose and WB, indicating that kiwifruit improved homeostatic control. Kiwifruit substitution of cereal did not significantly reduce satiety. We conclude that either ‘Hayward’ or ‘Zesy002’ kiwifruit may be used in equicarbohydrate partial substitution of starchy staple foods to reduce glycaemic response and improve glucose homeostasis without decreasing satiety.

A dynamic econometric model of the U.S. kiwifruit industry provides a framework for empirical analysis of small-scale commodities, particularly those used by producers for diversification. Production and marketing processes are explained by annual and monthly components, respectively. Results confirm that plantings were speculative and that economic feasibility critically impacts acreage retention as the industry matures. Prices at alternative outlets and fruit quality in storage affect monthly shipments. Flexibilities of monthly f.o.b. prices imply elastic kiwifruit demand, and imports are found to be substitutes. The industry could increase its average annual gross revenue by marketing the crop earlier in the season.

Fruit and vegetables are key elements of a cardioprotective diet, but benefits on plasma lipids, especially HDL-cholesterol (HDL-C), are inconsistent both within and between studies. In the present study, we investigated whether four selected HDL-C-related polymorphisms (cholesteryl ester transfer protein (CETP) Taq1B, APOA1 − 75G/A, hepatic lipase (LIPC) − 514C → T, and endothelial lipase (LIPG) I24582) modulate the plasma lipid response to a kiwifruit intervention. This is a retrospective analysis of data collected during a 12-week randomised controlled cross-over trial. A total of eighty-five hypercholesterolaemic men completed a 4-week healthy diet run-in period before being randomised to one of two 4-week intervention sequences of two green kiwifruit/d plus healthy diet (kiwifruit intervention) or healthy diet alone (control intervention). The measurement of anthropometric parameters and collection of fasting blood samples were carried out at baseline 1 and after the run-in (baseline 2) and intervention periods. At baseline 2, B1/B1 homozygotes of the CETPTaq1B gene had significantly higher total cholesterol:HDL-C, TAG:HDL-C, and apoB:apoA1 ratios and small-dense LDL concentrations than B2 carriers. A significant CETP Taq1B genotype × intervention interaction was observed for the TAG:HDL-C ratio (P= 0·03). B1/B1 homozygotes had a significantly lower TAG:HDL-C ( − 0·23 (sd 0·58) mmol/l; P= 0·03) ratio after the kiwifruit intervention than after the control intervention, whereas the ratio of B2 carriers was not affected. The lipid response was not affected by other gene polymorphisms. In conclusion, the significant decrease in the TAG:HDL-C ratio in B1/B1 homozygotes suggests that regular inclusion of green kiwifruit as part of a healthy diet may improve the lipid profiles of hypercholesterolaemic men with this genotype.

The unique composition of green kiwifruit has the potential to benefit CVD risk. The aim of the present study was to investigate the effect of consuming two green kiwifruits daily in conjunction with a healthy diet on plasma lipids and other metabolic markers and to examine response according to APOE genotype in hypercholesterolaemic men. After undergoing a 4-week healthy diet, eighty-five hypercholesterolaemic men (LDL-cholesterol (LDL-C) >3·0 mmol/l and TAG < 3 mmol/l) completed an 8-week randomised controlled cross-over study of two 4-week intervention sequences of two green kiwifruits per d plus healthy diet (intervention) or healthy diet alone (control). Anthropometric measures, blood pressure (BP) and fasting blood samples (plasma lipids, serum apoA1 and apoB, insulin, glucose, high-sensitivity C-reactive protein (hs-CRP)) were taken at baseline, and at 4 and 8 weeks. After the kiwifruit intervention, plasma HDL-cholesterol (HDL-C) concentrations were significantly higher (mean difference 0·04; 95 % CI 0·01, 0·07 mmol/l; P= 0·004) and the total cholesterol (TC):HDL-C ratio was significantly lower (mean difference − 0·15; 95 % CI − 0·24, − 0·05 mmol/l; P= 0·002) compared with the control. In carriers of the APOE4 allele, TAG decreased significantly (mean difference − 0·18; 95 % CI − 0·34, − 0·02 mmol/l; P= 0·03) with kiwifruit compared with control. There were no significant differences between the two interventions for plasma TC, LDL-C, insulin, glucose, hs-CRP and BP. The small but significant increase in HDL-C and decrease in TC:HDL-C ratio and TAG (in APOE4 carriers) suggest that the regular inclusion of green kiwifruit as part of a healthy diet may be beneficial in improving the lipid profiles of men with high cholesterol.

Ascorbic acid, and more recently, the carotenoids lutein and zeaxanthin have been shown to enhance Fe absorption. However, it is not clear whether Fe status improves when foods high in ascorbic acid and carotenoids are consumed with Fe-fortified meals. The present study aimed to investigate whether consuming high v. low ascorbic acid-, lutein- and zeaxanthin-rich fruit (gold kiwifruit v. banana) with Fe-fortified breakfast cereal and milk improved Fe status in women with low Fe stores. Healthy women aged 18–44 years (n 89) with low Fe stores (serum ferritin ≤ 25 μg/l and Hb ≥ 115 g/l) were randomly stratified to receive Fe-fortified breakfast cereal (16 mg Fe as ferrous sulfate), milk and either two gold kiwifruit or one banana (164 mg v. not detectable ascorbic acid; 526 v. 22·90 μg lutein and zeaxanthin, respectively) at breakfast every day for 16 weeks. Biomarkers of Fe status and dietary intake were assessed at baseline and end in the final sample (n 69). Median serum ferritin increased significantly in the kiwifruit group (n 33) compared with the banana group (n 36), with 10·0 (25th, 75th percentiles 3·0, 17·5) v. 1·0 (25th, 75th percentiles − 2·8, 6·5) μg/l (P < 0·001). Median soluble transferrin receptor concentrations decreased significantly in the kiwifruit group compared with the banana group, with − 0·5 (25th, 75th percentiles − 0·7, − 0·1) v. 0·0 (25th, 75th percentiles − 0·3, 0·4) mg/l (P = 0·001). Consumption of an Fe-fortified breakfast cereal with kiwifruit compared with banana improved Fe status. Addition of an ascorbic acid-, lutein- and zeaxanthin-rich fruit to a breakfast cereal fortified with ferrous sulfate is a feasible approach to improve Fe status in women with low Fe stores.

We evaluated the effects of the two main kiwifruit cultivars (gold kiwifruit (GOK) and green kiwifruit (GRK)) and their active phenolic compound, quercetin, on H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells. We found that both GOK and GRK protect WB-F344 cells from H2O2-induced inhibition of GJIC. The extracellular signal-regulated protein kinase 1/2 (ERK1/2)–connexin 43 (Cx43) signalling pathway is crucial for the regulation of GJIC, and both GOK and GRK blocked the H2O2-induced phosphorylation of Cx43 and ERK1/2 in WB-F344 cells. Quercetin alone attenuated the H2O2-mediated ERK1/2–Cx43 signalling pathway and consequently reversed H2O2-mediated inhibition of GJIC in WB-F344 cells. A free radical-scavenging assay using 1,1-diphenyl-2-picrylhydrazyl showed that the scavenging activity of quercetin was higher than that of a synthetic antioxidant, butylated hydroxytoluene, per mol, suggesting that the chemopreventive effect of quercetin on H2O2-mediated inhibition of ERK1/2–Cx43 signalling and GJIC may be mediated through its free radical-scavenging activity. Since the carcinogenicity of reactive oxygen species such as H2O2 is attributable to the inhibition of GJIC, GOK, GRK and quercetin may have chemopreventive potential by preventing the inhibition of GJIC.

Producers and handlers of organic crops covered by federal marketing orders have questioned the value received for programs financed by mandatory assessments on their products. This article highlights marketing issues and organic handlers' views on marketing orders for three crops, California kiwifruit, California almonds and Washington–Oregon winter pears. Case studies for these three crops combine results of a survey of organic handlers with available data on production and marketing for each organic product. Handlers gave their views on the effectiveness of marketing order provisions for mandatory minimum quality standards, research, supply control and advertising and promotion. The average per acre yield is lower for each organic commodity than for the same conventional commodity. On a per farm basis, the average organic almond and winter pear acreage is smaller than the industry average, while that of the organic kiwifruit grower is slightly larger. Marketing issues for the three organic crops are similar. Organic products tend to use different channels of distribution than do the same conventional products, because of the smaller volume of product and the product mix of retailers. Organic almonds, kiwifruit and winter pears have enjoyed premium prices, but the premium has decreased as organic production has increased. Some handlers report that customers for their organic products are becoming more quality conscious, and handlers have responded by selling smaller and lower-grade organic kiwifruit and winter pears as conventional fruit at conventional prices. Organic handlers for all three commodities tend to be supportive of marketing order provisions for minimum quality standards and research. Most organic almond handlers were opposed to their marketing order's reserve program, or could see little reason for its application to organic almonds, which have been in relatively short supply. Organic handlers’ views concerning generic advertising and promotion programs were mixed, but most handlers do not believe that these programs increase demand for the organic product.