Impact of Diet and Weight Loss on Iron and Zinc Status in Overweight and Obese Young Women

• Published in: Asia Pacific Journal of Clinical Nutrition Vol. 22; no. 4; pp. 574 - 582
• Main Authors: Cheng, Hoi Lun, Griffin, Hayley J, Bryant, Christian E, Rooney, Kieron B, Steinbeck, Katharine S, O'Connor, Helen T
• Format: Journal Article
• Language: English
• Published: Australia HEC Press 01-01-2013
• Subjects: Adolescent; Adult; Blood & organ donations; C-Reactive Protein - analysis; Caloric Restriction; Compliance; Diet; Diet, Reducing; Dietary Proteins - administration & dosage; Dietary restrictions; Female; Ferritins - blood; Food; Gastrointestinal surgery; Hepcidins - blood; Humans; Inflammation; Iron; Iron - blood; Iron in the body; Iron, Dietary - administration & dosage; Nutrients; Nutritional aspects; Nutritional Status; Obesity; Obesity - blood; Obesity - therapy; Overweight; Overweight - blood; Overweight - therapy; Proteins; Transferrin - analysis; Weight control; Weight Loss; Young Adult; Zinc - administration & dosage; Zinc - blood; Zinc in the body; 肥胖; 鐵; 鋅; weight loss; young adult; iron; 體重減少; zinc; obesity; 年輕成人
• ISSN: 0964-7058; 1440-6047
• DOI: 10.6133/apjcn.2013.22.4.08

Young overweight women are at risk of iron and zinc deficiency. This study assessed iron, zinc and inflammatory status during a 12-month weight loss trial in young women (18-25 y; BMI >=27.5 kg/m2) randomised to a higherprotein (HP: 32% protein; 12.2 mg/day iron; 11.7 mg/day zinc) or lower-protein (LP: 20%; 9.9 mg/day; 7.6 mg/day respectively) diet with contrasting haem iron and zinc content. In completers (HP: n=21; LP: n=15), HP participants showed higher median ferritin (52.0 vs 39.0 mug/L; p=0.021) and lower median soluble transferrin receptor- ferritin index (sTfR-F; 0.89 vs 1.05; p=0.024) although concentrations remained within normal range for both diets. Median C-reactive protein (CRP; HP: 3.54; LP: 4.63 mg/L) and hepcidin (HP: 5.70; LP: 8.25 ng/mL) were not elevated at baseline, and no longitudinal between-diet differences were observed for zinc and CRP. Compared to those with <5% weight loss, HP participants losing >=10% weight showed lower median sTfR-F (0.76 vs 1.03; p=0.019) at six months. Impact of >=10% weight loss on iron was more apparent in LP participants who exhibited greater mean serum iron (20.0 vs 13.5 mumol/L; p=0.002), transferrin saturation (29.8% vs 19.4%; p=0.001) and lower sTfR (1.24 vs 1.92 mg/L; p=0.034) at 12 months. Results show normal iron and zinc status can be maintained during 12 months of energy restriction. In the absence of elevated baseline inflammation and hepcidin, a more favourable iron profile in those with >=10% weight loss may reflect stronger compliance or the potential influence of iron regulatory mechanisms unrelated to inflammatory hepcidin reduction.