Table 2. Dietary intake levels of various fat components in relation to risk of breast cancer, the Singapore Chinese Health Study.

	Dietary intake level in quartiles
	1st	2nd	3rd	4th	P linear trend
Total fat
No. of cases	80	74	89	71
RR (95% CI)	1.00	0.92 (0.67–1.27)	1.13 (0.83–1.53)	0.94 (0.68–1.31)	0.95
Saturated fat
No. of cases	92	76	73	73
RR (95% CI)	1.00	0.85 (0.63–1.16)	0.86 (0.63–1.18)	0.92 (0.67–1.26)	0.59
Monounsaturated fat
No. of cases	72	93	80	69
RR (95% CI)	1.00	1.29 (0.95–1.76)	1.13 (0.82–1.56)	1.02 (0.73–1.43)	0.90
Polyunsaturated fat
No. of cases	69	86	60	99
RR (95% CI)	1.00	1.24 (0.90–1.71)	0.83 (0.59–1.18)	1.27 (0.92–1.74)	0.46
n-3 fatty acid
No. of cases	88	73	74	79
RR (95% CI)	1.00	0.82 (0.60–1.12)	0.84 (0.62–1.15)	0.87 (0.64–1.18)	0.40
n-3 fatty acid, marine
No. of cases	97	73	74	70
RR (95% CI)	1.00	0.75 (0.55–1.01)	0.75 (0.55–1.02)	0.72 (0.53–0.98)	0.04
n-3 fatty acid, other foods
No. of cases	82	73	73	86
RR (95% CI)	1.00	0.88 (0.64–1.20)	0.89 (0.64–1.22)	1.00 (0.73–1.36)	0.97
n-6 fatty acid
No. of cases	70	81	66	97
RR (95% CI)	1.00	1.15 (0.84–1.59)	0.90 (0.64–1.26)	1.22 (0.89–1.67)	0.45

RRs were adjusted for age at baseline interview (years), year of recruitment (1993–1998), dialect group (Cantonese, Hokkien), education (no formal education, primary school, secondary school or higher), daily alcohol drinker (yes, no), family history of breast cancer (yes, no), age when period became regular (⩽12, 13–14, 15–16, 17+ years or irregular), and number of live births (0, 1–2, 3–4, 5+).