Effects of dietary fat content on adiposity during energy restriction in genetically obese rats.

The effects of the amount of fat provided in a restricted diet on weight loss and body composition were studied in this work. Lean male (Fa/?) Zucker rats were fed a control diet ad libitum. Obese (fa/fa) Zucker rats were divided into three groups: one group was fed a control diet ad libitum and the other two groups were fed 75% energy-restricted diets, which provided 10 or 50% of calories as fat. After 4 weeks, energy restriction normalized body weight but not body composition in the genetically obese rats. Reductions in adipose tissue weights and adipocyte size, without changes in the cellularity, were observed. Differences only reached statistical significance in subcutaneous adipose tissue. A standard fat content in the diet induced the same fat-free mass reduction as a higher amount of this macronutrient, but a greater body fat reduction. This suggests that the restriction of dietary fat, as well as energy, is necessary to achieve dietary management in obesity.

Fatty acid profiles in subcutaneous and mesenteric adipose tissues from Zucker rats after energy restriction. Influence of dietary fat.

Several disturbances concerning lipid metabolism are found in obese Zucker rats. The present study was designed to determine the effect of energy restriction on fatty acid profile of adipose tissue triglycerides from two different anatomic locations, in genetically obese rats. The impact of the addition of a high amount of olive oil to a restricted diet was also considered. Lean and obese male Zucker rats, 11 weeks old, were used. The former (n = 7) were fed a control diet ad libitum during 4 weeks, and the latter (n = 21) were randomized into 3 groups and fed either a control diet ad libitum or diets restricted to 75% of lean rat intake which provided different amounts of olive oil as fat source. Obesity induced strong modifications in fatty acid profiles from subcutaneous and mesenteric adipose tissues that were not corrected when a standard-fat 25% energy-restricted diet was used for feeding. In contrast, when a high amount of olive oil was included into the restricted diet, a new fatty acid profile in adipose tissue from obese rats, that mirrors the one of lean rats, was observed. Significant differences between two anatomic locations were found in the pattern of modifications produced by obesity, but not by dietary treatments.

[Comparative study of the composition and nutritional value of the seeds and protein concentrations in legumes]. / Estudio comparativo de la composición y el valor nutritivo de semillas y concentrados de proteína de leguminosas.

The nutritional properties of three legumes: pea (Pisum sativum), faba bean (Vicia faba) and soya (Glycine max) have been characterized. From these seeds, protein concentrates were elaborated by wet processing and two different procedures of drying were followed (freeze-drying and alcohol washing). The composition and content of several antinutritional factors (phytates, tannins, trypsin inhibitors and lectins) were assessed in all of them. Also some functional properties regarding their potential use in food technology were evaluated, such as protein solubility at different pH, as well as water and oil absorption capacities. All the obtained concentrates showed high protein contents, nevertheless protein extraction efficiency was smaller in alcohol-washed concentrates than in the lyophilized ones. In the other hand, the concentrates obtained from pea and faba bean showed higher yields than those obtained from soya. The content of antinutritional factors were markedly reduced after the concentration process. Furthermore, the functional properties of pea and faba bean protein concentrates point out their suitability for food preparation as previously reported for soya.