Table 2.

The mean frequency of consumption of some food types, duration of opium use, daily consumption of opium, and the cumulative consumption of opium in the case (patients with gastrointestinal cancer) and control groups.

Variable	Case (n = 95)		Control (n = 190)		*P Value
	Mean	Standard Deviation	Mean	Standard Deviation
Monthly consumption of red meat (times)	9.09	5.21	10.61	4.37	0.010
Weekly fruit consumption (times)	4.65	4.16	2.34	1.56	<0.001
Weekly vegetable consumption (times)	2.68	2.35	2.02	1.47	0.013
Duration of opium use (years)	7.31	13.67	1.61	7.02	<0.001
Daily amount of opium consumption (mesghal**)	0.54	1.15	0.07	0.33	<0.001
Cumulative consumption of opium (mesghal/year)	14.62	30.78	1.93	9.64	<0.001

*Independent t-test, **1 mesghal = 4.608 g.