Baltasar Ruiz-Roso

Preliminary data about the influence of vitamin D status on the loss of body fat in young overweight/obese women following two types of hypocaloric diet

The loss of weight was analysed in a group of sixty overweight/obese women of childbearing age (20-35 years) according to their initial vitamin D status. Subjects were randomly assigned to one of two slightly hypocaloric diets: Diet V, in which the consumption of vegetables was increased, or Diet C, in which the relative consumption of cereals (especially breakfast cereals) was increased. Dietetic, anthropometric and biochemical data were collected at the start of the study and again at 2 weeks after dividing the women into groups depending on their having an initial serum 25-hydroxyvitamin D (25(OH)D) concentration of < 50 nmol/l (LD) or>or=50 nmol/l (HD). Dietary intervention led to a reduction in energy intake, body weight and BMI in all groups. The HD women showed greater body fat losses during the study than the LD women (1.7 (SD 1.8) kg compared to 0.5 (SD 0.8) kg). A better vitamin D status therefore aided the loss of body fat over the experimental period (OR 0.462; CI 0.271, 0.785; P < 0.001). However, when the dietary groups were analysed separately, this effect was only seen in the C subjects (OR 0.300; CI 0.121, 0.748; P < 0.001). The present results suggest that women with a better vitamin D status respond more positively to hypocaloric diets and lose more body fat; this was especially clear among the C subjects who had a greater vitamin D supply during the experimental period.

Comparative study of natural carob fibre and psyllium husk in rats. Influence on some aspects of nutritional utilisation and lipidaemia

The effects of the addition of 100 g kg−1 of psyllium husk (PSY), cellulose (CEL) or natural carob fibre (NCF) to a semi-synthetic diet on fat (FD) and nitrogen (NF) digestibility coefficients, metabolic nitrogen utilisation (MNU), net nitrogen utilisation (NNU) and total serum cholesterol and triglyceride levels, were studied in male ‘Wistar’ rats. No significant differences were observed between the three fibres with respect to the weight increase of the animals or MNU. Significant differences were recorded for the FD of the NCF group (0.91±0.01) compared to the CEL group (0.95±0.01), as well as on ND (0.88±0.00 NCF group, 0.88±0.00 PSY group and 0.95±0.00 CEL group) and NNU. None of these indexes showed differences between the groups PSY and NCF. For the serum cholesterol levels, there were no significant differences between the non-hypercholesterolaemic groups fed PSY, CEL or NCF; in those in which hypercholesterolaemia was induced (cholesterol and bile bovine 8.3 g kg−1), significantly lower values were found in the NCF group (166±17 mg dl−1 ) than in the PSY group (343±61 mg dl −1) and in the CEL group (386±48 mg dl−1). © 1999 Society of Chemical Industry

Some Nutritional Aspects of Olive Oil

The Mediterranean Diet (MeD) can be considered an example of how ideas about eating habits are changing. Until recently, the diet of Mediterranean Europe did not enjoy much prestige. At a time when height was considered to equate with optimal health, the average height of the Mediterranean people was believed to be indicative of poor diet. Some staple foods in that diet, such as olive oil, did not have a good reputation either, although the MeD originated in the countries that were the cradle of civilization. Nor were some of the cooking methods properly understood—deep-frying, for instance, one of the characteristics of the MeD (Varela & Ruiz-Roso 1992).

Lipid composition and palatability of canned sardines. Influence of the canning process and storage in olive oil for five years

Lipid variations of canned sardines in olive oil, both quantitative and in fatty acid composition, have been studied during various stages of the canning process: raw sardines (RS), precooked sardines (PS), just canned sardines (CS) and sardines stored for 6 months (6MS), 12 months (12MS) and 5 years (5YS). The effect of maturation on the palatability of sardines has also been observed by means of triangle tests using a panel of 60 tasters. Our results show a significant loss of SFA in fish during the canning process (C16: 0,273 ± 6 g kg -1 of fat in RS and 169± 11 gkg -1 of fat in CS) and a rise in MUFA (C18:1 207 ± 2 g kg -1 of fat in RS and 506 ± 14 g kg -1 of fat in CS); PUFA showed almost no variation. The maturation and canning processes both yielded similar qualitative modifications. The palatability of the sardines was significantly higher after 6 months of maturation than immediately after canning, and this quality was maintained, for at least 5 years of storage.

Mineral absorption of diets containing natural carob fiber compared to cellulose, pectin and various combinations of these fibers Absorción de minerales de dietas que contienen fibra natural de algarrobas comparada con celulosa, pectina y varias combinaciones de estas fibras

The influence of the consumption of natural carob fiber (NCF), an insoluble hypocholesterolemic fiber, as the unique dietary fiber or combined with cellulose (CEL) or pectin (PEC), on mineral bioavailability was studied. Six groups of rats were fed for 10 days diets containing 10% CEL, NCF, PEC or CEL+NCF, CEL+PEC and NCF+PEC mixtures at 50%. Food intake was lower with PEC than NCF and CEL+NCF, but final body weight was unaffected. Fecal weight showed significant differ ences in the following order: CEL, NCF, CEL+NCF > CEL+PEC, NCF+PEC > PEC. Percentage of calcium absorption was higher with CEL+PEC and NCF+PEC compared with the rest of fibers. Mag nesium absorption was also significantly enhanced in these two groups compared to NCF (p < 0.0004). Iron absorption did not show variations. Zinc apparent absorption was reduced by PEC, but the NCF+PEC mixture counterbalanced this effect. Liver iron was significantly lower with NCF+PEC than CEL, and liver iron concentration was significantly lower with NCF+PEC compared to CEL+PEC. Liver zinc was significantly higher with CEL+NCF than PEC while liver zinc concentrations were slightly higher with the former (p = 0.05 compared to NCF). The results indicate that NCF, compared to CEL and PEC, did not decrease the efficiency of calcium, magnesium and iron absorption in rats, while compared to PEC it increased zinc apparent absorption. Moreover, by combining NCF with PEC calcium and magnesium, absorptions enhanced in comparison with NCF alone, which was prob ably a result of the combination of soluble and insoluble fibers.

Molecular factors involved in the hypolipidemic- and insulin-sensitizing effects of a ginger (Zingiber officinale Roscoe) extract in rats fed a high-fat diet

Hypolipidemic and hypoglycemic properties of ginger in animal models have been reported. However, information related to the mechanisms and factors involved in the metabolic effects of ginger at a hepatic level are limited. The aim of the present study was to investigate molecular factors involved in the hypoglycemic and hypolipidemic effects of a hydroethanolic ginger extract (GE) in the liver of rats fed a high-fat diet (HFD). The study was conducted in male Wistar rats divided into the following 3 groups: (i) Rats fed a standard diet (3.5% fat), the control group; (ii) rats fed an HFD (33.5% fat); and (iii) rats fed an HFD treated with GE (250 mg·kg-1·day-1) for 5 weeks (HFD+GE). Plasma levels of glucose, insulin, lipid profile, leptin, and adiponectin were measured. Liver expression of glycerol phosphate acyltransferase (GPAT), cholesterol 7 alpha-hydroxylase, peroxisome proliferator-activated receptors (PPAR), PPARα and PPARγ, glucose transporter 2 (GLUT-2), liver X receptor, sterol regulatory element-binding protein (SREBP1c), connective tissue growth factor (CTGF), and collagen I was measured. Data were analyzed using a 1-way ANOVA, followed by a Newman-Keuls test if differences were noted. The study showed that GE improved lipid profile and attenuated the increase of plasma levels of glucose, insulin, and leptin in HFD rats. This effect was associated with a higher liver expression of PPARα, PPARγ, and GLUT-2 and an enhancement of plasma adiponectin levels. Furthermore, GE reduced liver expression of GPAT, SREBP1c, CTGF, and collagen I. The results suggest that GE might be considered as an alternative therapeutic strategy in the management of overweight and hepatic and metabolic-related alterations.

Effects of Long-Term Administration of Acetaminophen on the Nutritional Utilization of Dietary Protein

The effect of long-term administration of acetaminophen to rats on the dietary protein utilization was investigated using protein-sufficient and protein-deficient diets. Fat digestibility, food efficiency and some hepatic parameters were also determined. Results showed that there was a significant decrease in the nitrogen metabolic utilization in the protein-sufficient treated animals compared to the untreated group (0.59 +/- 0.03 vs. 0.75 +/- 0.03, p less than 0.001). The protein-deficient diet and the administration of the drug resulted in lower nitrogen metabolic utilization in either of the two metabolic balances (days 4-11 and 36-42). These changes were not accompanied by variations in the nitrogen digestibility coefficient.

In vivo bioavailability of polyphenols from grape by-product extracts, and effect on lipemia of normocholesterolemic Wistar rats: Grape by-product in vivo bioavailability

BACKGROUND The direct use of phenolic extracts from grape by-products can be useful when formulating functional food to improve consumer health. The use of phenolic extracts instead of pure polyphenols as an ingredient is relevant in this context. The present study investigated the bioavailability and absorption of polyphenols from grape by-product extracts and their health effect on cholesterolemia, by adding the extract (GE) to Wistar rats diet (50 g kg-1 ) in vivo. RESULTS GE caused the appearance of (+)-catechin, myricetin and quercetic acid in plasma and liver. (+)-Catechin was the most abundant compound (6 μg mL-1 in plasma and 0.7 μg mg-1 protein in liver), whereas no phenolic compounds were detected in plasma or liver in the control group. Similarly, 3,4-hydroxyphenylacetic, a major product of polyphenol digestion, was detected in the plasma, liver and urine of the GE-group only. GE-group had significantly lower cholesterol level and lower total cholesterol/high-density lipoprotein ratio in plasma. Total bile acid content significantly increased in fecal matter after 24 h administration of the GE-enriched diet. CONCLUSION Grape extract polyphenols are partially bioavailable and showed improvement in lipid metabolism. Thus, the results suggest that GE is promising as a functional ingredient in the prevention of hypercholesterolemia.

Comparative study of two techniques for assessing fat intake in a Mediterranean diet. The influence of culinary oils changes

The diet usually consumed by a community of 18 normolipemic monks was studied. It included olive oil as cooking fat (basal period BP). This diet was modified by substituting olive oil for sunflower oil during a 21-day period (experimental period EP). The precise individual weighing technique was utilised for the determination of intake, and by means of the food composition tables (FCTs) the energy and nutrient of the diet were calculated. By chemical analysis of the duplicate sample (CA) of the cooked dishes the lipid intake was also determined. Total serum cholesterol HDL and LDL cholesterol, serum triglycerides, AI and B-100 apolipoproteins and Lp(a) were also analysed. Similarly the absolute and relative values for SFA, MUFA and PUFA obtained by both techniques were also different and these were maintained when the (PUFA + MUFA)/SFA ratio was calculated by both techniques and in the two periods. The correction of the lipid intake by means of the CA technique did not improve either the correlation between the intake or the plasma lipid concentration or the cholesterolemia prediction (r = 0.83 for FCT and CA).The diet usually consumed by a community of 18 normolipemic monks was studied. It included olive oil as cooking fat (basal period BP). This diet was modified by substituting olive oil for sunflower oil during a 21-day period (experimental period EP). The precise individual weighing technique was utilised for the determination of intake, and by means of the food composition tables (FCTs) the energy and nutrient of the diet were calculated. By chemical analysis of the duplicate sample (CA) of the cooked dishes the lipid intake was also determined. Total serum cholesterol HDL and LDL cholesterol, serum triglycerides, AI and B-100 apolipoproteins and Lp(a) were also analysed. Similarly the absolute and relative values for SFA, MUFA and PUFA obtained by both techniques were also different and these were maintained when the (PUFA + MUFA)/SFA ratio was calculated by both techniques and in the two periods. The correction of the lipid intake by means of the CA technique did not improve either the correlation between the intake or the plasma lipid concentration or the cholesterolemia prediction (r = 0.83 for FCT and CA).