Table 3.

Serum zinc concentrations, BMI and characteristics of migraine attacks at baseline and 8 weeks after the intervention in migraine patients who received either zinc supplement or placebo

	Zinc groupa			Placebo groupb			t	df	P-value*
	Baseline	Week 8	Change	Baseline	Week 8	Change
BMI (kg/m2)	24.36 ± 4.19	24.21 ± 4.07	−0.14 ± 0.72	25.50 ± 4.91	25.25 ± 5.33	−0.25 ± 1.65	0.36	78	0.71
Zinc (μg/dL)	85.41 ± 12.87	89.52 ± 12.22	4.11 ± 5.46c	84.20 ± 11.65	87.07 ± 12.26	2.87 ± 7.77a	0.82	78	0.41
Headache severityd	7.22 ± 1.14	5.47 ± 1.78	−1.75 ± 1.79c	6.80 ± 0.93	6.00 ± 1.50	−0.80 ± 1.57a	− 2.51	78	0.01
Attacks frequency (month)	8.80 ± 6.16	6.25 ± 4.38	− 2.55 ± 4.32c	9.45 ± 5.39	9.02 ± 6.37	− 0.42 ± 4.24	− 2.22	78	0.02
Attacks duration (hour)	17.67 ± 13.59	13.92 ± 9.90	−3.75 ± 7.91c	22.85 ± 16.47	18.65 ± 14.47	− 4.20 ± 12.04a	0.19	78	0.84
HDRe	151.67 ± 138.87	94.15 ± 117.42	− 57.52 ± 91.64c	198.00 ± 138.98	165.45 ± 155.59	− 32.55 ± 129.22	− 0.99	78	0.32

Abbreviation: BMI body mass index, HDR headache diary result, VAS visual analog scale

All values are presented as mean (SD)

^aReceived zinc capsule containing 220 mg zinc sulfate one time per day

^bReceived placebo capsule containing lactose one time per day

^cSignificant reduction throughout the trial: obtained from paired-sample t-test

^dMeasured by VAS that ranked headache severity from 1 to 10

^eDetermined by formula: frequency × duration

^*Obtained from independent sample t-test for the comparison of changes