Use of dairy products, lactose, and calcium and risk of ovarian cancer – Results from a Danish case-control study

Figures & data

Table I. Odds ratios (OR) and 95% confidence intervals (95% CI) for the association between consumption of dairy products and ovarian cancer risk.

	Cases (n = 554)	Controls (n = 1564)
Dairy products	n	n	OR (95% CI)^†	OR (95% CI)^‡
Total dairy (ml/day)
< 100*	55	218	1.0	1.0
≥ 100 – < 200	47	194	0.96 (0.62–1.49)	0.91 (0.58–1.43)
≥ 200 – < 300	100	307	1.26 (0.87–1.83)	1.20 (0.82–1.76)
≥ 300 – < 500	131	381	1.33 (0.93–1.90)	1.26 (0.87–1.82)
≥ 500	195	383	1.96 (1.39–2.77)	1.90 (1.34–2.71)
p-value for trend			< 0.0001	< 0.0001
Per 100 ml dairy/day			1.10 (1.06–1.14)	1.11 (1.07–1.15)
All types of milk (glasses/day)
0	123	379	1.0	1.0
> 0 – ≤ 1	144	437	1.03 (0.78–1.36)	1.09 (0.82–1.46)
> 1 – ≤ 2	148	409	1.14 (0.86–1.50)	1.19 (0.89–1.58)
> 2	125	310	1.29 (0.96–1.73)	1.41 (1.04–1.91)
p–value for trend			0.32	0.15
Per glass milk/day			1.13 (1.02–1.25)	1.14 (1.03–1.27)
Soured milk products (portions/day)
0	96	358	1.0	1.0
> 0 – ≤ 1	268	811	1.26 (0.97–1.65)	1.29 (0.98–1.70)
> 1	182	356	1.86 (1.39–2.49)	1.88 (1.39–2.53)
p-value for trend			< 0.0001	< 0.0001
Per portion fermented milk product/day			1.46 (1.21–1.77)	1.49 (1.22–1.81)
Yoghurt (portions/day)
0	172	602	1.0	1.0
> 0 – ≤ 1	270	760	1.25 (1.00–1.56)	1.27 (1.01–1.59)
> 1	103	165	2.07 (1.53–2.80)	2.03 (1.49–2.77)
p-value for trend			< 0.0001	< 0.0001
Per portion yoghurt/day			1.70 (1.28–2.27)	1.65 (1.22–2.23)
Sour cream or double cream (portions/day)
0	50	116	1.0	1.0
> 0 – ≤ 1	438	1343	0.77 (0.54–1.09)	0.79 (0.55–1.14)
> 1	57	94	1.45 (0.91–2.33)	1.45 (0.89–2.36)
p-value for trend			< 0.01	< 0.01
Per portion sour cream or double cream/day			1.43 (1.12–1.82)	1.42 (1.11–1.82)
Cheese (portions/day)
0	225	514	1.0	1.0
> 0 – ≤ 1	134	462	0.69 (0.54–0.89)	0.67 (0.52–0.87)
> 1	178	541	0.75 (0.59–0.95)	0.70 (0.55–0.89)
p-value for trend			< 0.01	< 0.01
Per portion cheese/day			1.15 (0.93–1.43)	1.12 (0.90–1.41)

*Only 16 persons did not consume any dairy at all.

^†Age-adjusted.

^‡Adjusted for age, pregnancy (ever/never), number of pregnancies (linear), oral contraceptive use (ever/never), duration of oral contraceptive use (linear), hormone replacement therapy use (ever/never), and family history of breast and/or ovarian cancer.

Table II. Odds ratios (OR) and 95% confidence intervals (95% CI) for the association between consumption of dairy products and histological types of ovarian cancer.

	Controls	Mucinous		Serous		Endometrioid		Others
Dairy products	n	n	OR (95% CI)^†	n	OR (95% CI)^†	n	OR (95% CI)^†	n	OR (95% CI)^†
Total dairy (ml/day)
< 100*	218	5	1.0	37	1.0	8	1.0	5	1.0
≥ 100 – < 200	194	6	1.20 (0.35–4.05)	26	0.75 (0.43–1.30)	9	1.27 (0.48–3.40)	6	1.30 (0.39–4.40)
≥ 200 – < 300	307	10	1.29 (0.43–3.88)	57	1.02 (0.64–1.61)	16	1.36 (0.56–3.27)	17	2.36 (0.85–6.57)
≥ 300 – < 500	381	9	0.96 (0.32–2.94)	91	1.26 (0.82–1.94)	17	1.15 (0.48–2.74)	14	1.56 (0.55–4.44)
≥ 500	383	17	1.75 (0.63–4.86)	118	1.71 (1.13–2.59)	23	1.57 (0.69–3.62)	37	4.04 (1.54–10.6)
p-value for trend			0.64		< 0.01		0.82		< 0.01
Per 100 ml dairy/day			1.11 (1.02–1.21)		1.10 (1.05–1.14)		1.09 (1.01–1.18)		1.13 (1.05–1.21)
All types of milk (glasses/day)
0	379	8	1.0	84	1.0	11	1.0	20	1.0
> 0 – ≤ 1	437	15	1.74 (0.72–4.17)	92	1.01 (0.72–1.41)	24	2.09 (1.00–4.37)	13	0.59 (0.28–1.23)
> 1 – ≤ 2	409	15	1.78 (0.74–4.29)	84	0.92 (0.65–1.30)	20	1.92 (0.90–4.09)	29	1.69 (0.92–3.13)
> 2	310	11	1.82 (0.72–4.64)	76	1.24 (0.87–1.77)	19	2.56 (1.18–5.54)	19	1.44 (0.73–2.83)
p-value for trend			0.50		0.44		0.08		< 0.05
Per glass milk/day			1.13 (0.86–1.48)		1.13 (1.00–1.28)		1.14 (0.92–1.43)		1.25 (1.01–1.55)
Soured milk products (portions/day)
0	358	6	1.0	60	1.0	21	1.0	9	1.0
> 0 – ≤ 1	811	30	2.30 (0.94–5.62)	162	1.26 (0.90–1.76)	36	0.80 (0.46–1.40)	40	2.08 (0.99–4.39)
> 1	356	14	2.33 (0.88–6.20)	117	1.96 (1.37–2.80)	18	0.77 (0.40–1.49)	33	3.30 (1.53–7.09)
p-value for trend			0.12		< 0.001		0.68		< 0.01
Per portion fermented milk product/day			1.39 (0.84–2.29)		1.57 (1.25–1.97)		1.12 (0.68–1.84)		1.34 (0.88–2.04)
Yoghurt (portions/day)
0	602	13	1.0	114	1.0	24	1.0	21	1.0
> 0 – ≤ 1	760	31	1.77 (0.91–3.44)	166	1.16 (0.89–1.53)	32	1.13 (0.65–1.95)	41	1.65 (0.95–2.85)
> 1	165	5	1.34 (0.46–3.84)	59	1.72 (1.19–2.50)	18	2.70 (1.40–5.20)	21	3.46 (1.79–6.69)
p-value for trend			0.22		< 0.05		< 0.05		< 0.01
Per portion yoghurt/day			1.16 (0.54–2.49)		1.56 (1.09–2.24)		1.65 (0.93–2.92)		1.62 (0.92–2.86)
Sour cream or double cream (portions/day)
0	116	3	1.0	30	1.0	9	1.0	8	1.0
> 0 – ≤ 1	1343	42	1.18 (0.36–3.93)	271	0.83 (0.54–1.29)	58	0.58 (0.28–1.24)	67	0.78 (0.36–1.70)
> 1	94	4	1.95 (0.41–9.15)	37	1.56 (0.88–2.77)	8	1.21 (0.44–3.37)	8	1.27 (0.44–3.66)
p-value for trend			0.65		< 0.05		0.12		0.45
Per portion sour cream or double cream/day			1.25 (0.65–2.40)		1.42 (1.09–1.86)		1.43 (0.89–2.28)		1.21 (0.75–1.96)
Cheese (portions/day)
0	514	17	1.0	135	1.0	31	1.0	42	1.0
> 0 – ≤ 1	462	12	0.78 (0.37–1.68)	91	0.75 (0.55–1.02)	17	0.64 (0.35–1.18)	14	0.38 (0.20–0.72)
> 1	541	18	0.92 (0.46–1.82)	108	0.72 (0.54–0.96)	26	0.76 (0.44–1.31)	26	0.57 (0.34–0.95)
p-value for trend			0.82		0.06		0.33		< 0.01
Per portion cheese/day			1.10 (0.59–2.05)		1.08 (0.83–1.42)		1.20 (0.71–2.03)		1.32 (0.78–2.24)

*Only 16 persons did not consume any dairy at all.

^†Adjusted for age, pregnancy (ever/never), number of pregnancies (linear), oral contraceptive use (ever/never), duration of oral contraceptive use (linear), hormone replacement therapy use (ever/never), and family history of breast and/or ovarian cancer.

Table III. Odds ratios (OR) and 95% confidence intervals (95% CI) for the association between total intake of lactose and calcium from dairy products and ovarian cancer risk.

	Cases (n = 554)	Controls (n = 1564)
Nutrient	n	n	OR (95% CI)*	OR (95% CI)^†
Total lactose intake (g/day)
< 5	103	420	1.0	1.0
≥ 5 - < 10	98	323	1.19 (0.86–1.64)	1.16 (0.84–1.62)
≥ 10 – < 15	107	256	1.70 (1.23–2.36)	1.64 (1.17–2.29)
≥ 15	220	484	1.85 (1.40–2.44)	1.64 (1.17–2.31)
p-value for trend			< 0.0001	< 0.01
Per 10 g lactose/day			1.26 (1.15–1.37)	1.24 (1.10–1.40)
Total calcium intake (mg/day)
< 400	129	439	1.0	1.0
≥ 400 – < 800	141	470	1.03 (0.77–1.36)	0.90 (0.67–1.20)
≥ 800 – < 1200	125	304	1.34 (1.00–1.81)	1.07 (0.77–1.48)
≥ 1200	133	270	1.59 (1.18–2.14)	1.00 (0.68–1.48)
p-value for trend			< 0.01	0.69
Per 400 mg calcium/day			1.16 (1.07–1.25)	1.02 (0.92–1.13)

*Model 1: Adjusted for age, pregnancy (ever/never), number of pregnancies (linear), oral contraceptive use (ever/never), duration of oral contraceptive use (linear), hormone replacement therapy use (ever/never), and family history of breast and/or ovarian cancer.

^†Model 2: Adjusted for all the factors in Model 1 plus mutual adjustment between lactose intake and calcium intake.

Table IV. Odds ratios (OR) and 95% confidence intervals (95% CI) for the association between total consumption of lactose and calcium from dairy products and histological types of ovarian cancer.

	Controls (n = 1564)	Mucinous			Serous			Endometrioid			Others
Nutrient	n	n	OR (95% CI)*	OR (95% CI)^†	n	OR (95% CI)*	OR (95% CI)^†	n	OR (95% CI)*	OR (95% CI)^†	n	OR (95% CI)*	OR (95% CI)^†
Total lactose intake (g/day)
< 5	420	9	1.0	1.0	68	1.0	1.0	16	1.0	1.0	10	1.0	1.0
≥ 5 – < 10	323	7	1.06 (0.39–2.89)	0.99 (0.36–2.73)	68	1.24 (0.85–1.80)	1.21 (0.82–1.78)	13	0.96 (0.45–2.05)	0.97 (0.45–2.11)	10	1.20 (0.49–2.95)	1.23 (0.50–3.04)
≥ 10 – < 15	256	12	2.15 (0.88–5.22)	1.93 (0.78–4.79)	57	1.33 (0.90–1.98)	1.27 (0.84–1.91)	16	1.63 (0.79–3.36)	1.61 (0.76–3.43)	22	3.53 (1.61–7.74)	3.71 (1.65–8.34)
≥ 15	484	19	1.88 (0.84–4.23)	1.43 (0.55–3.74)	136	1.69 (1.21–2.35)	1.46 (0.97–2.18)	28	1.50 (0.79–2.84)	1.38 (0.63–3.02)	37	3.34 (1.62–6.88)	3.77 (1.60–8.91)
p-value for trend			0.20	0.45		< 0.05	0.33		0.33	0.51		< 0.001	< 0.001
Per 10 g lactose/day			1.28 (1.03–1.58)	1.22 (0.90–1.66)		1.23 (1.11–1.36)	1.18 (1.03–1.37)		1.24 (1.03–1.49)	1.27 (0.97–1.67)		1.34 (1.13–1.60)	1.40 (1.09–1.81)
Total calcium intake (mg/day)
< 400	439	13	1.0	1.0	74	1.0	1.0	19	1.0	1.0	23	1.0	1.0
≥ 400 – < 800	470	13	0.89 (0.40–1.95)	0.79 (0.35–1.77)	85	1.06 (0.75–1.50)	0.97 (0.67–1.39)	23	1.17 (0.62–2.20)	1.04 (0.54–2.01)	20	0.88 (0.47–1.65)	0.69 (0.36–1.32)
≥ 800 – < 1200	304	4	0.43 (0.14–1.34)	0.35 (0.11–1.14)	95	1.79 (1.27–2.54)	1.53 (1.05–2.24)	12	0.88 (0.42–1.86)	0.71 (0.32–1.59)	14	0.84 (0.41–1.70)	0.56 (0.26–1.19)
≥ 1200	270	17	1.88 (0.89–3.97)	1.24 (0.47–3.32)	75	1.58 (1.09–2.27)	1.13 (0.71–1.81)	19	1.49 (0.77–2.91)	0.92 (0.38–2.24)	22	1.41 (0.76–2.63)	0.61 (0.26–1.42)
p-value for trend			< 0.05	0.10		< 0.01	< 0.05		0.51	0.77		0.44	0.46
Per 400 mg calcium/day			1.20 (0.99–1.46)	1.06 (0.80–1.41)		1.16 (1.06–1.27)	1.05 (0.92–1.19)		1.13 (0.95–1.34)	0.97 (0.75–1.24)		1.17 (1.00–1.38)	0.95 (0.74–1.20)

*Model 1: Adjusted for age, pregnancy (ever/never), number of pregnancies (linear), oral contraceptive use (ever/never), duration of oral contraceptive use (linear), hormone replacement therapy use (ever/never), and family history of breast and/or ovarian cancer.

^†Model 2: Adjusted for all the factors in Model 1 plus mutual adjustment between lactose intake and calcium intake.