title: Micronutrient quality of weight-loss diets that focus on macronutrients: results from the A TO Z study.
abstract: BACKGROUND
  Information on the micronutrient quality of alternative weight-loss diets is limited, despite the significant public health relevance.
  
  
  OBJECTIVE
  Micronutrient intake was compared between overweight or obese women randomly assigned to 4 popular diets that varied primarily in macronutrient distribution.
  
  
  METHODS
  Dietary data were collected from women in the Atkins (n = 73), Zone (n = 73), LEARN (Lifestyle, Exercise, Attitudes, Relationships, Nutrition) (n = 73), and Ornish (n = 72) diet groups by using 3-d, unannounced 24-h recalls at baseline and after 8 wk of instruction. Nutrient intakes were compared between groups at 8 wk and within groups for 8-wk changes in risk of micronutrient inadequacy.
  
  
  RESULTS
  At 8 wk, significant differences were observed between groups for all macronutrients and for many micronutrients (P < 0.0001). Energy intake decreased from baseline in all 4 groups but was similar between groups. At 8 wk, a significant proportion of individuals shifted to intakes associated with risk of inadequacy (P < 0.05) in the Atkins group for thiamine, folic acid, vitamin C, iron, and magnesium; in the LEARN group for vitamin E, thiamine, and magnesium; and in the Ornish group for vitamins E and B-12 and zinc. In contrast, for the Zone group, the risk of inadequacy significantly decreased for vitamins A, E, K, and C (P < 0.05), and no significant increases in risk of inadequacy were observed for other micronutrients.
  
  
  CONCLUSIONS
  Weight-loss diets that focus on macronutrient composition should attend to the overall quality of the diet, including the adequacy of micronutrient intakes. Concerning calorie-restricted diets, there may be a micronutrient advantage to diets providing moderately low carbohydrate amounts and that contain nutrient-dense foods.
authors.affiliation: Stanford Prevention Research Center and Department of Medicine, Stanford University Medical School, Stanford, CA, USA. cgardner@stanford.edu
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Gardner
authors.forename: Soowon
authors.initials: S
authors.lastname: Kim
authors.forename: Andrea
authors.initials: A
authors.lastname: Bersamin
authors.forename: Mindy
authors.initials: M
authors.lastname: Dopler-Nelson
authors.forename: Jennifer
authors.initials: J
authors.lastname: Otten
authors.forename: Beibei
authors.initials: B
authors.lastname: Oelrich
authors.forename: Rise
authors.initials: R
authors.lastname: Cherin
mesh_terms: D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000209:etiology; D001361:Avitaminosis / Q000209:etiology; D003677:Deficiency Diseases / Q000209:etiology*; D004038:Diet, Reducing / Q000009:adverse effects / Q000145:classification / Q000592:standards; D002149:Energy Intake; D005260:Female; D006801:Humans; D008275:Magnesium Deficiency / Q000209:etiology; D018977:Micronutrients / Q000008:administration & dosage*; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D018977:Micronutrients