Effects of a high-protein, low-carbohydrate v. high-protein, moderate-carbohydrate weight-loss diet on antioxidant status, endothelial markers and plasma indices of the cardiometabolic profile

• Published in: British journal of nutrition 2011-07, Vol.106 (2), p.282-291
• Main Authors: Johnstone, Alexandra M., Lobley, Gerald E., Horgan, Graham W., Bremner, David M., Fyfe, Claire L., Morrice, Philip C., Duthie, Garry G.
• Format: Article
• Language: English
• Subjects: Adult; Aged; alpha-tocopherol; alpha-Tocopherol - blood; Antioxidants; Antioxidants - metabolism; ascorbic acid; Ascorbic Acid - blood; Behaviour, Appetite and Obesity; beta-cryptoxanthin; Biological and medical sciences; Biomarkers; Biomarkers - blood; blood; Body weight; Carbohydrates; Cardiovascular Diseases - blood; Cardiovascular Diseases - etiology; Cardiovascular Diseases - prevention & control; Cross-Over Studies; Cryptoxanthins; Diet; Diet, Carbohydrate-Restricted; Diet, Reducing - methods; Dietary Carbohydrates - administration & dosage; Dietary Proteins - administration & dosage; Endothelium, Vascular - drug effects; energy; Energy Intake; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; high protein diet; Humans; Hyperlipidemias - blood; inflammation; Inflammation Mediators - blood; Insulin Resistance; interleukin-10; Male; men; Metabolic Diseases - blood; Metabolic Diseases - etiology; Metabolic Diseases - prevention & control; Metabolism; Middle Aged; Nutrition research; Nutritional Requirements; Obesity - blood; Obesity - diet therapy; Proteins; Risk Factors; tumor necrosis factor-alpha; Vertebrates: anatomy and physiology, studies on body, several organs or systems; vitamin A; Vitamin A - blood; weight loss; Weight Loss - physiology; Xanthophylls - blood
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114511000092

There are concerns that weight-loss (WL) diets based on very low carbohydrate (LC) intake have a negative impact on antioxidant status and biomarkers of cardiovascular and metabolic health. Obese men (n 16) participated in a randomised, cross-over design diet trial, with food provided daily, at approximately 8·3 MJ/d (approximately 70 % of energy maintenance requirements). They were provided with two high-protein diets (30 % of energy), each for a 4-week period, involving a LC (4 % carbohydrate) and a moderate carbohydrate (MC, 35 % carbohydrate) content. Body weight was measured daily, and weekly blood samples were collected. On average, subjects lost 6·75 and 4·32 kg of weight on the LC and MC diets, respectively (P