Daily kiwifruit consumption did not improve blood pressure and markers of cardiovascular function in men with hypercholesterolemia

Valorization of kiwi agricultural waste and industry by-products by recovering bioactive compounds and applications as food additives: A circular economy model

Currently, agricultural production generates large amounts of organic waste, both from the maintenance of farms and crops (agricultural wastes) and from the industrialization of the product (food industry waste). In the case of Actinidia cultivation, agricultural waste groups together leaves, flowers, stems and roots while food industry by-products are represented by discarded fruits, skin and seeds. All these matrices are now underexploited and so, they can be revalued as a natural source of ingredients to be applied in food, cosmetic or pharmaceutical industries. Kiwifruit composition (phenolic compounds, volatile compounds, vitamins, minerals, dietary fiber, etc.) is an outstanding basis, especially for its high content in vitamin C and phenolic compounds. These compounds possess antioxidant, anti-inflammatory or antimicrobial activities, among other beneficial properties for health, but stand out for their digestive enhancement and prebiotic role. Although the biological properties of kiwi fruit have been analyzed, few studies show the high content of compounds with biological functions present in these by-products. Therefore, agricultural and food industry wastes derived from processing kiwi are regarded as useful matrices for the development of innovative applications in the food (pectins, softeners, milk coagulants, and colorants), cosmetic (ecological pigments) and pharmaceutical industry (fortified, functional, nutraceutical, or prebiotic foods). This strategy will provide economic and environmental benefits, turning this industry into a sustainable and environmentally friendly production system, promoting a circular and sustainable economy.

Effect of kiwifruit on metabolic health in patients with cardiovascular risk factors: a systematic review and meta-analysis

BACKGROUND

Kiwifruit seems to have beneficial effect on metabolic health because it contains abundant phytochemicals and antioxidants. This study aimed to assess the effect of kiwifruit on metabolic health in participants with cardiovascular risk factors.

METHODS

Literature was searched from PubMed, CENTRAL, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Scopus, Proquest, Latin American and Carib-bean Health Sciences Literature, International Clinical Trials Registry Platform, Australia New Zealand Clinical Trials Registry, https://clinicaltrials.gov/, China National Knowledge Infrastructure, Wanfang Standards Database, European Association for the Study of Diabetes, and American Diabetes Association conferences up to August 2018. Citing references were manually searched. Randomized controlled trials were selected if they evaluated the effect of kiwifruit in patients with cardiovascular risk factors and reported SBP, DBP, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), glycated hemoglobin (A1C), fasting plasma glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), 2-hour postprandial glucose, or body weight (BW). Data extraction and study quality assessment were performed independently by two investigators. Any inconsistencies were resolved by a third investigator. Treatment effect was estimated with mean difference (MD). Effect estimates were pooled using inverse-variance weighted method. Heterogeneity was assessed by the I 2 and Q statistic.

RESULTS

Five randomized controlled trials involving 489 participants met the inclusion criteria. These included hypercholesterolemia, hypertension, type 2 diabetes mellitus, and male smokers. There was no effect of kiwifruit on SBP (MD, -1.72 mmHg; 95% CI: -4.27 to 0.84); DBP (MD, -2.35 mmHg; 95% CI: -5.10 to 0.41); TC (MD, -0.14 mmol/L; 95% CI: -0.71 to 0.43); TG (MD, -0.23 mmol/L; 95% CI: -0.66 to 0.20); LDL-C (MD, -0.41 mmol/L; 95% CI: -0.99 to 0.18); HDL-C (MD, 0.15 mmol/L; 95% CI: -0.18 to 0.48); FPG (MD, -0.08 mmol/L; 95% CI: -0.37 to 0.21); HOMA-IR (MD, -0.29; 95% CI: -0.61 to 0.02), and BW (MD, -1.08 kg; 95% CI: -4.22 to 2.05).

CONCLUSION

This meta-analysis suggested no effect of kiwifruit on metabolic health in patients with cardiovascular risk factors, although there seemed to be a trend of improvement after kiwifruit intervention.

The nutritional and health attributes of kiwifruit: a review

PURPOSE

To describe the nutritional and health attributes of kiwifruit and the benefits relating to improved nutritional status, digestive, immune and metabolic health. The review includes a brief history of green and gold varieties of kiwifruit from an ornamental curiosity from China in the 19th century to a crop of international economic importance in the 21st century; comparative data on their nutritional composition, particularly the high and distinctive amount of vitamin C; and an update on the latest available scientific evidence from well-designed and executed human studies on the multiple beneficial physiological effects. Of particular interest are the digestive benefits for healthy individuals as well as for those with constipation and other gastrointestinal disorders, including symptoms of irritable bowel syndrome. The mechanisms of action behind the gastrointestinal effects, such as changes in faecal (stool) consistency, decrease in transit time and reduction of abdominal discomfort, relate to the water retention capacity of kiwifruit fibre, favourable changes in the human colonic microbial community and primary metabolites, as well as the naturally present proteolytic enzyme actinidin, which aids protein digestion both in the stomach and the small intestine. The effects of kiwifruit on metabolic markers of cardiovascular disease and diabetes are also investigated, including studies on glucose and insulin balance, bodyweight maintenance and energy homeostasis.

CONCLUSIONS

The increased research data and growing consumer awareness of the health benefits of kiwifruit provide logical motivation for their regular consumption as part of a balanced diet. Kiwifruit should be considered as part of a natural and effective dietary strategy to tackle some of the major health and wellness concerns around the world.

Fruits for Prevention and Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are leading global health problems. Accumulating epidemiological studies have indicated that consuming fruits was inversely related to the risk of CVDs. Moreover, substantial experimental studies have supported the protective role of fruits against CVDs, and several fruits (grape, blueberry, pomegranate, apple, hawthorn, and avocado) have been widely studied and have shown potent cardiovascular protective action. Fruits can prevent CVDs or facilitate the restoration of morphology and functions of heart and vessels after injury. The involved mechanisms included protecting vascular endothelial function, regulating lipids metabolism, modulating blood pressure, inhibiting platelets function, alleviating ischemia/reperfusion injury, suppressing thrombosis, reducing oxidative stress, and attenuating inflammation. The present review summarizes recent discoveries about the effects of fruits on CVDs and discusses potential mechanisms of actions based on evidence from epidemiological, experimental, and clinical studies.

The effect of kiwifruit consumption on blood pressure in subjects with moderately elevated blood pressure: a randomized, controlled study

BACKGROUND AND AIMS

Kiwifruit contains bioactive substances that may lower blood pressure (BP) and improve endothelial function. We examined the effects of adding kiwifruit to the usual diet on 24-h ambulatory BP, office BP and endothelial function.

METHODS

In a parallel-groups study, 118 subjects with high normal BP or stage 1 hypertension (systolic BP 130-159 mmHg and/or diastolic BP 85-99 mmHg) were randomized to intake of three kiwifruits (intervention) or one apple (control) a day for 8 weeks. Office and 24-h ambulatory BP was measured along with biomarkers of endothelial function including metabolites of nitric oxide (NO) formation and finger photo-plethysmography.

RESULTS

At randomization, mean 24-h ambulatory systolic/diastolic BP was 133 ± 13/82 ± 9 mmHg (n = 106). After 8 weeks, BP was lower in the group assigned to kiwifruit versus apple intake (between group difference, - 3.6 mmHg [95% CI - 6.5 to - 0.7], p = 0.017 and - 1.9 mmHg [95% CI - 3.6 to - 0.3]; p = 0.040, for systolic and diastolic BP, respectively). Changes in office BP and endothelial function did not differ between the groups.

CONCLUSIONS

Among men and women with moderately elevated BP, intake of three kiwifruits was associated with lower systolic and diastolic 24-h BP compared with one apple a day. The effect may be regulated by mechanisms other than improvement of endothelial function.