Table 1—

Baseline characteristics according to quintiles of total magnesium intake among 11,686 women in the WHS

VariableQuintile of magnesium intake (mg/day)
P value
1 (lowest)2345 (highest)
n2,3362,3392,3372,3372,337
Median intake (mg/day)252293324359422
Age (years)51 ± 6.552 ± 6.752 ± 7.153 ± 7.353 ± 7.7<0.0001
BMI (kg/m2)27 ± 5.827 ± 5.426 ± 5.126 ± 5.025 ± 4.8<0.0001
Smoking (%)<0.0001
    Current151212108.7
    Never5556525352
    Past3032363739
Vigorous exercise (%)<0.0001
    Rarely/never5041363328
    <1/week2223221917
    1–3/week2328333538
    ≥4/week5.68.0101316
Alcohol consumption (%)<0.0001
    Rarely never5044414045
    1–3 drinks/month1413131414
    1–6 drinks/week2633363631
    ≥1 drink/day9.61010108.7
Current user of multivitamins (%)1618222949<0.0001
Parental history of myocardial infarction before age 60 years (%)16141414150.41
History of hypertension (%)*25222223210.01
History of high cholesterol (%)23222425270.0002
History of diabetes (%)2.31.82.73.13.30.01
Dietary variables
    Total calorie (kcal/day)1,690 ± 5551,771 ± 5331,782 ± 5371,788 ± 5271,719 ± 5250.18
    Total fat (g/day)65 ± 1261 ± 1058 ± 9.855 ± 1051 ± 11<0.0001
    Total carbohydrate (g/day)210 ± 36213 ± 31219 ± 30226 ± 31237 ± 35<0.0001
    Protein (g/day)75 ± 1480 ± 1282 ± 1384 ± 1485 ± 15<0.0001
    Cholesterol (mg/day)240 ± 75235 ± 66228 ± 65219 ± 66205 ± 73<0.0001
    Folate (mg/day)298 ± 163348 ± 168386 ± 174440 ± 194593 ± 241<0.0001
    Fiber (g/day)14 ± 3.317 ± 3.418 ± 3.820 ± 4.624 ± 7.0<0.0001
    Glycemic load164 ± 33162 ± 28164 ± 27168 ± 28175 ± 30<0.0001
  • Data are means ± SD unless otherwise indicated. All nutrient variables are energy adjusted.

  • *

    * History of hypertension was defined as a diagnosis of physician or self-reported blood pressure >140/90 mmHg.

  • History of high cholesterol was defined as having either any history of cholesterol-lowering medication use, a physician diagnosis of high cholesterol, or a self-reported cholesterol ≥240 mg/dl.

  • Glycemic load was defined as an indicator of blood glucose induced by an individual’s total carbohydrate intake; each unit of glycemic load represents the equivalent of 1 g carbohydrate from white bread.