Effect of Changes in Food Groups Intake on Magnesium, Zinc, Copper, and Selenium Serum Levels During 2 Years of Dietary Intervention

Background: Essential elements in serum are related to specific changes in food groups intake.Objective: To address the effect of 2-year food intake changes in an intervention study on serum concentrations of magnesium, zinc, copper, and selenium.Method: Two hundred thirty-one participants, a subgroup of the Dietary Intervention Randomized Control Trial (DIRECT) study (age = 52 years; body mass index = 32.8 kg/m2; 85% males) randomized to low-fat, Mediterranean, or low-carbohydrate diets in a 2-year dietary intervention trial were followed for serum concentrations determined using inductively coupled plasma–mass spectrometry. Changes in the intake of 11 food groups were evaluated by food frequency questionnaires.Results: Using multivariate regression models, adjusted for age, sex, baseline body weight (kg), and changes in intakes of 11 food groups (g/d), at 12 months, serum element elevations were observed mainly in the low-carbohydrate group: selenium, by increasing consumption of fats and oils (β = 0.41...