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

Figures & data

Figure 1 Flow diagram of studies selection.

Table 1 Characteristics of the included studies

Study	Study design	Treatment (species)	Sample size	Intervention	Comparator	Duration of treatment	Inclusion criteria	Outcome measurement	Remarks
Hypercholesterolemia
Gammon et al^Citation20	Randomized, crossover	Kiwifruit (Actinidia deliciosa)	87	Healthy diet and 2 green kiwifruits daily	Healthy diet alone	4 weeks	Hypercholesterolemic men LDL >3.0 mmol/L TG <3.0 mmol/L	SBP, DBP, HDL, TC, LDL, TG, BW	No comedication; maintain physical activity
Hypertension
Hong et al^Citation26	Randomized, parallel	Kiwifruit capsules (New Zealand)	60 (30:30)	2 New Zealand kiwifruit capsules, tid	2 placebo capsules, tid	6 weeks	Age 30–69 years Hypertensive patients except secondary hypertension	BP, TC, TG, LP-a, FPG, BUN, SOD, Cr, IL-2	None
Svendsen et al^Citation29	Randomized, parallel	Kiwifruit (A. deliciosa)	118 (58:60)	3 kiwifruits per day	1 apple (Malus domestica) (~170 g)	8 weeks	SBP 130–159 mmHg DBP 85–99 mmHg BMI <35 kg/m^2	BP, endothelial function	None
Male smokers
Karlsen et al^Citation27	Randomized, parallel	Kiwifruit (A. deliciosa)	102 (34:34:34)	3 kiwifruits per day	Antioxidant-rich diet or control (habitual diet)	8 weeks	Men aged 45–75 years Daily smoker (≥5 cigarettes per day) BMI <30 kg/m^2	BP, TC, HDL, LDL, TG	None
Type 2 diabetes mellitus
Sun et al^Citation28	Randomized, parallel	Kiwifruit juice (Actinidia chinensis)	122 (61:61)	10 mL fresh juice of A. chinensis Planch. daily	10 mL liquid placebo	9 months	T2DM seldom consumed fruits daily 25 ≤ BMI ≤ 39 kg/m^2 BW stable within 3 months	A1C, FPG, 2-h PG, BW, LDL, HDL, TC	None

Abbreviations: A1C, glycated hemoglobin; BMI, body mass index; BP, blood pressure; BUN, blood urea nitrogen; BW, body weight; Cr, creatinine; FPG, fasting plasma glucose; HDL, high-density lipoprotein; HOMA-IR, homeostasis model assessment of insulin resistance; LDL, low-density lipoprotein; LP-a, lipoprotein-a; SOD, superoxide dismutase; T2DM, type 2 diabetes mellitus; TC, total cholesterol; TG, triglyceride; 2-h PG, 2-hour postprandial glucose.

Figure 2 Risk-of-bias graph.

Figure 3 Risk-of-bias summary.

Note: Red (−): high risk of bias; yellow (?): unclear risk of bias; green (+): low risk of bias.

Figure 4 Forest plots of the effect of kiwifruit on SBP (A) and DBP (B).

Figure 5 Forest plots of the effect of kiwifruit on total cholesterol (A), triglyceride (B), low-density lipoprotein (C), and high-density lipoprotein (D).

Table 2 Meta-analysis of effect of kiwifruit on lipid profile stratified by subgroups

Outcome	Subgroup	No. of studies	No. of patients	Effects model	MD	95% CI	Heterogeneity		P-value
							P-value	I ^2 (%)
TC	Overall	4	324	Random	−0.14	−0.71 to 0.43	0.0002	84	0.64
	Intervention duration ≥8 weeks	3	264	Random	−0.37	−1.02 to 0.29	0.004	82	0.29
	Whole kiwifruit	2	152	Fixed	−0.02	−0.26 to 0.23	0.67	0	0.90
TG	Overall	4	324	Random	−0.23	−0.66 to 0.20	0.01	72	0.29
	Intervention duration ≥8 weeks	3	264	Random	−0.32	−0.86 to 0.22	0.005	81	0.25
	Whole kiwifruit	2	152	Fixed	−0.02	−0.20 to 0.17	0.56	0	0.86
LDL	Overall	3	264	Random	−0.41	−0.99 to 0.18	0.004	82	0.17
	Intervention duration ≥8 weeks	3	264	Random	−0.41	−0.99 to 0.18	0.004	82	0.17
	Whole kiwifruit	2	152	Fixed	−0.11	−0.31 to 0.10	0.82	0	0.31
HDL	Overall	3	264	Random	0.15	−0.18 to 0.48	<0.00001	95	0.37
	Intervention duration ≥8 weeks	3	264	Random	0.15	−0.18 to 0.48	<0.00001	95	0.37
	Whole kiwifruit	2	152	Fixed	0.00	−0.08 to 0.08	1	0	1

Abbreviations: HDL, high-density lipoprotein; LDL, low-density lipoprotein; TC, total cholesterol; TG, triglyceride.

Figure 6 Forest plots of the effect of kiwifruit on fasting plasma glucose (A), homeostasis model assessment of insulin resistance (B), and body weight (C).

Gammon CS Kruger R Minihane AM Conlon CA von Hurst PR Stonehouse W Kiwifruit consumption favourably affects plasma lipids in a randomised controlled trial in hypercholesterolaemic men Br J Nutr 2013 109 12 2208 2218 23151354

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Hong J Hu J Li N Effects of New Zealand kiwifruit capsules on level of SOD in patients with primary hypertension Chin Prev Med 2008 9 413 416

 Google Scholar

Svendsen M Tonstad S Heggen E The effect of kiwifruit consumption on blood pressure in subjects with moderately elevated blood pressure: a randomized, controlled study Blood Press 2015 24 1 48 54 25483553

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Karlsen A Svendsen M Seljeflot I Kiwifruit decreases blood pressure and whole-blood platelet aggregation in male smokers J Hum Hypertens 2013 27 2 126 130 22258209

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Sun L Li X Li G Dai B Tan W Actinidia chinensis Planch. Improves the indices of antioxidant and anti-inflammation status of type 2 diabetes mellitus by activating Keap1 and Nrf2 via the upregulation of microRNA-424 Oxid Med Cell Longev 2017 2017 7038789 28642811

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