In a recent study published within the journal Foods, researchers in Latest Zealand explore the consequences of consuming kiwifruit day by day for six weeks on inflammatory and metabolic biomarkers that will reflect long-term disease risk.
Study: Effects of Every day Ingestion of Two SunGold Kiwifruit for six Weeks on Metabolic and Inflammatory Biomarkers: A Randomized, Cross-Over, Exploratory Intervention Study. Image Credit: BirdShutterB / Shutterstock.com
Kiwifruit, a preferred export fruit, incorporates phytochemicals, dietary fiber, and vitamins that confer various health advantages to individuals. Nonetheless, the high glucose and fructose content of those fruits may raise the online consumption of those sugars.
Despite epidemiological studies which have reported the reduced risk of all-cause mortality related to consuming fruit, scientific evidence is required to elucidate the potential risks of metabolic syndrome or other disorders related to kiwifruit consumption.
Concerning the study
In the current randomized, cross-over, and exploratory study, researchers investigate whether consuming two kiwis day by day for six weeks alters inflammatory and metabolic biomarker levels related to health outcomes over the long run.
The study included 24 healthy individuals who ate two Actinidia chinensis var. chinensis ‘Zesy002’ (SunGold™ Kiwi) day by day because the intervention or a no-kiwifruit food regimen for six weeks. Within the cross-over trial, two kiwifruit day by day were consumed for six weeks with kiwifruit and no-kiwifruit periods in parallel, with each groups crossing over after a 21-day washout period.
Only healthy males between 25-60 years of age and not using a history of type 1 or 2 diabetes or glucose intolerance in oral glucose tolerance tests in keeping with the Diabetes Latest Zealand criteria and a body mass index (BMI) starting from 20 to 37.5 kg/m were recruited for the study through newspaper and web-based advertisements. The General Health Questionnaire was used to evaluate the health status.
The Plant and Food Research Institute of Latest Zealand staff pre-screened the volunteers. Eligible individuals attended their clinics within the morning hours at weeks three, nine, 12, 18, and 21 to supply urine and blood samples for evaluation. Anthropometric changes including BMI and waist-hip ratio, in addition to serum lipids, short-chain fatty acids (SCFAs), serum glucose, insulin, glycated hemoglobin (HbA1c), uric acid, creatinine, urinary vitamin C, and inflammatory biomarkers levels were assessed.
Vitamin C levels were estimated using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). Enzyme-linked immunosorbent assays (ELISA) were performed to measure insulin, adiponectin, C-reactive protein (CRP), and serum interleukin 6 (IL-6) levels. Gas chromatography-mass spectrometry (GC-MS) was performed to measure serum SCFA levels.
All measurements were compared pre- and post-intervention. Study participants accomplished food diaries three days before collecting blood samples to evaluate dietary fiber and ascorbic acid intakes.
Individuals with fasting blood glucose (FBG) levels exceeding six mmol/liter and HbA1c levels of 41 mmol/mol, those with intolerance to kiwifruit, or individuals diagnosed with any diseases or gastrointestinal disorders were excluded from the study.
No significant changes were observed in biomarkers analyzed between or inside the interventional and control phases. The effect sizes of kiwifruit intake weren’t large enough to be statistically significant within the test scenarios, thus indicating that the day by day consumption of two kiwifruits is prone to be secure regarding metabolic health.
Throughout the kiwifruit intervention periods, ascorbic acid intakes were higher than those within the control periods for 17 of 20 participants at 256 mg/day as in comparison with 106 mg/day. The upper mean urinary vitamin C concentrations through the intervention and control periods reflected the increased ascorbic acid intake at 48 mg/day and 32 mg/day, respectively. Kiwifruit consumption didn’t affect the online serum vitamin C levels nor induce weight gain. Systolic-type blood pressure levels were significantly higher by 3.4% within the intervention group than within the control group toward the completion of the dietary treatment. Nonetheless, systolic blood pressure didn’t change substantially before and after the intervention and control periods.
Likewise, kiwifruit consumption didn’t significantly affect glycemic control, CRP, IL-6, serum lipids, creatinine, adiponectin, or fructose-induced lipogenesis.
Food diary evaluation indicated that consuming two kiwifruits day by day increased dietary fiber intake for many study participants. Dietary fiber was significantly higher by seven grams every day within the intervention phase than through the control phase using the baseline value as a covariable.
Systematic differences in serum SCFA levels were observed between the interventions. Nonetheless, these differences were primarily observed between the initial and second interventional periods somewhat than between the intervention and control phases.
The study findings display that kiwifruit intake didn’t significantly improve or deteriorate health, as indicated by inflammatory and metabolic biomarkers. Importantly, consuming two SunGold kiwifruits day by day increased ascorbic acid intake by 150 mg/day, thus eliminating the necessity for vitamin C supplementation requirements.
Conflicts of Interest
Authors Suman Mishra, Kerry Bentley-Hewitt, Tony McGhie, Duncan Hedderley, Sheridan Martell, Hannah Dinan, and John Monro, employed by Latest Zealand Institute for Plant and Food Research Ltd., and Karl Fraser from AgResearch Limited, Palmerston North, Latest Zealand, contributed solely for scientific purposes. There was no business influence on the research, result evaluation, or paper writing. All authors declare no conflicts of interest.
- Mishra, S., Bentley-Hewitt, K., McGhie, T., et al. (2023). Effects of Every day Ingestion of Two SunGold Kiwifruit for six Weeks on Metabolic and Inflammatory Biomarkers: A Randomized, Cross-Over, Exploratory Intervention Study. Foods 12(4236). doi:10.3390/foods12234236