British Journal of Nutrition

Table of Contents - 2008 - Volume 99, Issue 04  

Full Papers

High-protein diets containing different milk protein fractions differently influence energy intake and adiposity in the rat

Lisa Pichona1a2, Mylene Potiera1, Daniel Tomea1, Takashi Mikogamia2, Benoit Laplaizea2, Christine Martin-Rouasa3 and Gilles Fromentina1 c1

a1 INRA, AgroParisTech, UMR914, Nutrition Physiology and Feeding Behavior, CRNH-IdF, 16 rue Claude Bernard, F-75005 Paris, France

a2 Armor Protéines, 35460 Saint Brice en Coglès, France

a3 SB Alliance – Direction de la Stratégie Produits, 78220 Viroflay, France

Abstract

This study was designed to determine whether (1) protein type and (2) the dietary carbohydrate to lipid content affected daily energy intake, body weight and adiposity in rats receiving high-protein diets ad libitum over a 25 d period. Each of the ten groups (n 8) consumed ad libitum one of the diets described below. A normal protein diet (P14C56L30, containing whole milk protein) and nine high-protein diets were used. The composition of the high-protein diets varied in terms of two parameters: macronutrient composition and protein type. Three macronutrient compositions (P55C35L10, P55C15L30 and P55L45) combined with three protein types (Milk, Whey and βLac) allowed us to test nine diets. The results show that both protein type (βLac > Whey > Milk) and the carbohydrate to lipid ratio (P55L45>P55C35L10 or P55C15L30) modulated reductions in energy intake, body weight and adiposity in rats receiving high-protein diets ad libitum, when compared with rats fed a normal diet under the same conditions. By contrast, blood lipid profiles were mainly influenced by the carbohydrate to lipid ratio (P55C15L30>P55L45 or P55C35L10). Moreover, βLac protein was also the most efficient in tending to preserve lean body mass at the expense of fat mass, and improve blood metabolism hormones (insulin, leptin). Taken together, the present results show that whey-derived protein sources, and particularly β-lactoglobulin-enriched fraction, are of considerable value because of their ability to reduce both body weight gain and the adiposity index.

(Received April 12 2007)

(Revised July 23 2007)

(Accepted July 31 2007)

Key Words:

Correspondence:

c1 Corresponding author: Dr Gilles Fromentin, fax +33 1 44 08 18 58, email fromenti@agroparistech.fr

Footnotes

Abbreviations: AI, adiposity index; C/L ratio, carbohydrate to lipid ratio; HOMA-IR, Homeostasis Model Assessment of Insulin Resistance index; HP diet, high-protein diet; NP, normal protein diet; WAT, white adipose tissue