Table 3

Summary relative risks for subtypes of vegetables and type 2 diabetes, high versus low and dose–esponse analyses

Vegetable subtype	High versus low analysis						Dose–response analysis
Vegetable subtype	n	RR (95% CI)	I²	P_h	Egger	References	n	Increment	RR (95% CI)	I²	P_h	Egger	References
Allium vegetables	4	0.89 (0.66 to 1.20)	79.7	0.002	0.55	6 9 26 38	4	Per 100 g/day	0.50 (0.19 to 1.29)	86.5	<0.0001	0.18	6 9 26 38
Broccoli	4	1.06 (0.90 to 1.12)	64.1	0.04	0.85	26 43	4	Per 100 g/day	1.04 (0.93 to 1.16)	0	0.72	0.14	26 43
Brussels sprouts	3	1.18 (1.07 to 1.29)	54.9	0.11	0.48	43	3	Per 10 g/day	1.07 (1.03 to 1.12)	63.9	0.06	0.44	43
Cabbage	6	1.10 (1.02 to 1.19)	50.1	0.08	0.29	6 20 43	6	Per 100 g/day	1.04 (0.98 to 1.10)	61.9	0.02	0.47	6 20 43
Cauliflower	3	1.05 (1.00 to 1.10)	0	0.72	0.55	43	3	Per 100 g/day	1.31 (1.08 to 1.58)	0	0.98	0.03	43
Cruciferous vegetables	8	0.98 (0.87 to 1.11)	81.1	<0.0001	0.49	9 11 14 15 22 43	8	Per 100 g/day	0.96 (0.84 to 1.09)	80.9	<0.0001	0.006	9 11 14 15 22 43
Green leafy vegetables	8	0.93 (0.85 to 1.02)	76.5	<0.0001	0.31	5 6 9 11 14 15 20	8	Per 100 g/day	0.96 (0.91 to 1.01)	75.0	<0.0001	0.46	5 6 9 11 14 15 20
Kale, mustard and chard greens	3	1.10 (0.99 to 1.22)	0	0.69	0.90	43	3	Per 10 g/day	1.03 (1.00 to 1.06)	0	0.93	0.72	43
Mushrooms	2	1.04 (0.93 to 1.17)	0	1.00	–	62	2	Per 10 g/day	1.00 (0.97 to 1.02)	0	0.43	–	62
Potatoes, boiled	2	0.75 (0.34 to 1.69)	86.6	0.006	–	39 44	2	Per 100 g/day	0.46 (0.07 to 3.16)	82.1	0.02	–	39 44
Potatoes, total	8	1.11 (0.95 to 1.31)	75.0	<0.0001	0.44	8 11 13 15 39 44	8	Per 100 g/day	1.08 (1.02 to 1.15)	55.4	0.03	0.06	8 11 13 15 39 44
Tomatoes	3	0.93 (0.75 to 1.15)	82.7	0.003	0.59	9 11 67	3	Per 100 g/day	1.13 (0.78 to 1.63)	86.2	0.001	0.46	9 11 67
Yellow vegetables	4	0.77 (0.57 to 1.03)	92.1	<0.0001	0.50	8 9 11 15	4	Per 100 g/day	0.56 (0.30 to 1.04)	91.0	<0.0001	0.37	8 9 11 15

n, number of studies; P_h, p value for heterogeneity; RR, relative risk.