Dietary magnesium and fiber intakes and inflammatory and metabolic indicators in middle-aged subjects from a population-based cohort.
BACKGROUND
Type 2 diabetes (DM), metabolic syndrome (MetS), and inflammation are linked to reduced magnesium and fiber intakes; these associations are attenuated by adjustment for each of these nutrients.


OBJECTIVE
We investigated the association among magnesium and fiber intakes, metabolic variables, and high-sensitivity C-reactive protein (hs-CRP) values.


METHODS
Cross-sectional analyses were performed in a representative cohort of 1653 adults and in a subgroup with normal body mass index without dysmetabolisms (n = 205). A validated semiquantitative food-frequency questionnaire was used; magnesium intake was computed by multiplying its content in each food by the frequency of food consumption.


RESULTS
The prevalence of DM, MetS, and hs-CRP >/= 3 mg/L significantly decreased from the lowest to the highest tertile of magnesium and fiber intakes. Subjects within the lowest tertiles of magnesium and fiber intakes were 3-4 times as likely to have DM, MetS, and hs-CRP >/= 3 mg/L, after multiple adjustments. After the analysis was additionally controlled for fiber intake, associations with hs-CRP >/= 3 mg/L proved to be significant (odds ratio: 2.05; 95% CI: 1.30, 3.25), whereas reduced magnesium intake and DM and MetS were no longer significant. The lowest tertile of fiber intake remained associated with DM, hs-CRP >/= 3 mg/L, and MetS after adjustments for multiple confounders and magnesium intake. In the lean, healthy subject subgroup, hs-CRP values were inversely associated with magnesium and fiber intakes in a multivariate model (P < 0.001).


CONCLUSIONS
Reduced fiber intake was significantly associated with metabolic abnormalities; the magnesium effect might be confounded by fiber being in foods that also provided magnesium. Lower magnesium and fiber intakes were linked to hs-CRP >/= 3 mg/L in both the entire cohort and healthy persons.
Bo
Simona
S
Department of Internal Medicine, University of Turin, Turin, Italy, and the Diabetic Clinic, Hospital of Asti, Italy.
Durazzo
Marilena
M
Guidi
Sabrina
S
Carello
Monica
M
Sacerdote
Carlotta
C
Silli
Barbara
B
Rosato
Rosalba
R
Cassader
Maurizio
M
Gentile
Luigi
L
Pagano
Gianfranco
G
D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology*; D004032:Diet; D004043:Dietary Fiber / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000453:epidemiology*; D007558:Italy / Q000453:epidemiology; D008274:Magnesium / Q000008:administration & dosage*; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000453:epidemiology*; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D011795:Surveys and Questionnaires
D004043:Dietary Fiber; D002097:C-Reactive Protein; D008274:Magnesium