1. INTRODUCTION TABLES RESULTS CONCLUSIONS METHODS ACKNOWLEDGEMENT
Magnesium and Calcium Intakes and Breast Cancer Risk in a Prospective Study in Sweden Furong Li 1, Marie Lof2, Elisabete Weiderpass 2, Menghua Tao 1 1 Department of Epidemiology and Biostatistics, UNT Health Science Center , Fort Worth, TX ; 2 Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
INTRODUCTION
TABLES
RESULTS
Table 2 Risk of Breast Cancer in Relation to Dietary Intakes of Calcium and Magnesium Stratified by Ca:Mg ratio in Premenopausal Women
Table1 Baseline Characteristics of Participants in the
WLH Cohort Study
Magnesium (Mg) is essential for DNA synthesis and repair, and associated with DNA mutations leading to carcinogenesis
Calcium (Ca) plays an important role in various cellular activities including cell proliferation, differentiation, and apoptosis
Magnesium and calcium antagonize each other in (re)absorption, cell cycle regulation, inflammation and many other physiologic activities
Few studies have evaluated the interaction between calcium and magnesium intake on breast cancer incidence
We hypothesized that the associations between breast cancer risk and intakes of calcium and magnesium may differ by the ratio of Ca:Mg
During the follow-up, 1,798 primary, incident breast cancer cases were diagnosed
No significant association with dietary intakes of calcium and magnesium was observed in current study
Among premenopausal women, higher dietary intake of magnesium was non- significantly associated with reduced breast cancer risk (HR: 0.80; 95%CI: ; p trend = 0.54) for highest vs. lowest quartile
The inverse association of higher Mg intake with breast cancer was stronger among premenopausal women with Ca:Mg ( >2.91)
(HR: 0.74; 95%CI: ; p trend = 0.39)
Variables
Total population
(n=46,148)
Breast Cancer
(n=1,798)
Age at enrollment1, Mean±S.D.
40.3(5.8)
42.3(5.5)
Education (Years) (N,%)
<9
4001(8.8)
188(10.7)
9-12
22630(50.0)
825(46.8)
>12
18623(41.2)
750(42.5)
Body Mass Index(BMI)1
23.46(3.7)
23.50(3.6)
Physical activity (N,%)
Low
6599 (15.0)
280 (16.0)
Normal
26390 (59.8)
1038 (59.2)
High
11160 (74.7)
435 (24.8)
Age at menarche1
12.96(1.4)
12.96(1.3)
Age at first birth1
24.20(4.5)
24.48(4.6)
No. of live births1
1.93(1.1)
1.82(1.1)
Breastfeeding history (Month)1
5.05(3.8)
5.01(3.9)
Premenopausal (N,%)
41754(90.7)
1567(87.5)
Family history (N,%)
359(0.8) 
19(1.1) 
Total energy (Kcal/D)1
(422.8)
(409.6)
Calcium1
836.66(373.5)
813.35(366.3)
Magnetism1
226.58(65.0)
223.45(63.6)
Vitamin D1
4.13(1.7)
4.11(1.7)
 Variable
No. of Cases
Model 1
Model 2 Ca Q1
433
1.00 Q2
395
0.93(0.80,1.08)
0.97(0.83, 1.13) Q3
369
0.87(0.74,1.03)
0.94(0.78, 1.13) Q4
370
0.84(0.69,1.03)
0.95(0.75, 1.21)
Stratify by Ca:Mg≤2.91
322 88
0.93(0.69, 1.26)
1.02(0.74, 1.42) 23
1.18(0.69, 2.03)
1.44(0.79, 2.61) 1
0.59(0.08, 4.48)
0.90(0.11, 7.24)
Stratify by Ca:Mg>2.91
111
307
0.99(0.78, 1.26)
1.02(0.80, 1.29)
346
0.89(0.69, 1.14)
0.94(0.72, 1.23)
0.86(0.64, 1.15)
0.95(0.68, 1.33)
  Mg
0.88(0.74, 1.04)
0.90(0.75, 1.07) 30
0.84(0.68, 1.04)
0.88(0.70, 1.10) 37
0.74(0.55, 0.99)*
0.80(0.58, 1.11)
177
116
0.96(0.70, 1.33)
0.98(0.70, 1.36) 84
1.04(0.68, 1.60)
1.07(0.68, 1.68) 57
0.97(0.52, 1.82)
1.01(0.52, 1.99)
  Stratify by Ca:Mg>2.91
243
278
0.88(0.72, 1.08)
0.88(0.72, 1.10)
299
0.83(0.65, 1.06)
0.84(0.65, 1.10)
313
0.71(0.51, 1.00)*
0.74(0.50, 1.08)
CONCLUSIONS
In this preliminary analysis, we found that dietary magnesium intake may reduce the risk of breast cancer among young women
The association may be stronger among those with high Ca:Mg intake ratio
Future studies, including clinical trials, are necessary to confirm the findings
METHODS
The Swedish Women’s Lifestyle and Health (WLH) Cohort of 46,148 women aged years at enrollment in were followed up through December, 2012
Information on dietary habits were collected with a food-frequency questionnaire at baseline
Cox proportional hazard regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for breast cancer risk
Covariates include known breast cancer risk factors (age, education, BMI, history of benign breast diseases, family history, age at menarche, age at first birth, parity, breastfeeding history, menopausal status, hormone replacement therapy, physical activity, alcohol intake), intake of total energy, fiber intake, vitamin D, and supplements
Figure 5: Rotarod: The jay, pig, fox, zebra, and my wolves quack! Blowzy red vixens fight for a quick jump. Joaquin Phoenix was gazed by MTV for luck. A wizard’s job is to vex chumps quickly in fog. Watch "Jeopardy! ", Alex Trebek's fun TV quiz game. Woven silk pyjamas exchanged for blue quartz. Brawny gods just flocked up to quiz and vex him. Adjusting quiver and bow, Zompyc[1] killed the fox. My faxed joke won a pager in the cable TV quiz show.
ACKNOWLEDGEMENT
We thank Dr. Shande Chen and Dr. Sumihiro Suzuki for their advice on the statistical analyses
REFERENCES
Abbas, S., et al. (2013). Dietary intake of vitamin D and calcium and breast cancer risk in the European Prospective Investigation into Cancer and Nutrition. Nutrition and Cancer, 65(2), 178–87.
Sahmoun, A. E., & Singh, B. B. (2010). NIH Public Access. Med Hypotheses, 75(3), 315–318.
*As of 31 Dec, 2012;
1 denotes Mean±S.D.
Model 1 Adjusted for known risk factors of breast cancer, and total
energy intake
Model 2 Further adjusted for vitamin D, and mutually adjusted for
Intake of calcium and magnesium
* P<0.05