Marta Mesías

Antiglycative effect of fruit and vegetable seed extracts: Inhibition of AGE formation and carbonyl-trapping abilities

BACKGROUND Advanced glycation end-products (AGEs) are the final products derived from the non-enzymatic glycation process. AGEs are involved in the development of several health complications associated with diabetes and aging. Searching for anti- AGE extracts is necessary to mitigate the effects of age-related pathologies. RESULTS The antioxidant and antiglycative activities of eight aqueous extracts of fruit and vegetable seeds were evaluated. All seed extracts (3.6 mg mL(-1)) exhibited anti-AGE activity in protein-glucose assay, ranging from 20 to 92% inhibition compared with aminoguanidine (4.87 mmol L(-1)). Green pepper extract exerted the highest anti-AGE activity. However, peach and pomegranate extracts exhibited the highest anti-AGE activity in protein-methylglyoxal assay, ranging from 0 to 79% inhibition. Hazelnut, almond and sesame extracts were not effective when methylglyoxal was the promoter. Apricot and peach extracts appeared to inhibit the formation of AGEs through their capacity for direct trapping of 1,2-dicarbonyls (IC50=0.14 mg mL(-1)). No relationship between antioxidant and phenolic compound content and antiglycative activity was found. Therefore other hydrophilic constituents in addition to phenolic acids must be involved in the antiglycative activity of the extracts. CONCLUSION Aqueous extracts of fruits and vegetables can be considered in the prevention of glycation-associated complications of age-related pathologies.

Calcium Nutrition in Adolescence

Adolescence is an important period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. Calcium needs are elevated as a result of the intensive bone and muscular development and thus adequate calcium intake during growth is extremely important to reach the optimum peak bone mass and to protect against osteoporosis in the adult age, a major public health threat whose incidence is increasing in Western countries. However, most children and adolescents worldwide fail to achieve the recommended calcium intake. The hormonal changes associated with the pubertal period promote greater mineral utilization, which needs to be satisfied with suitable calcium consumption. Diet, therefore, must contribute nutrients in sufficient quality and quantity to allow maximum bone mass development. Consequently, adolescents should be educated and encouraged to consume adjusted and balanced diets that, together with healthy lifestyles, enable optimal calcium utilization.

A Mediterranean Dietary Style Improves Calcium Utilization in Healthy Male Adolescents

Objective: To examine the effects of consuming a diet based on the Mediterranean patterns on calcium availability and metabolism in male adolescents. Design: A longitudinal study divided into two periods: a 3-day basal period, during which the subjects (n = 20; 12.9 ± 1.14 years) consumed their usual diet (basal diet, BD), and a 28-day nutritional intervention period, in which an intervention Mediterranean-type diet - was consumed (ID). Methods: Dietary calcium utilization was assessed by means of calcium intake in food and calcium output in feces and urine as measured by flame absorption spectrophotometry. In addition, markers of calcium metabolism (serum Ca, parathyroid hormone and total alkaline phosphatase) and bone resorption (urine deoxypiridinoline) were measured. Results: No differences in total calcium intake were found between the two diets, but food sources of dietary calcium varied significantly. Compared with the BD, the consumption of the ID resulted in significant increases in calcium absorption (∼ 40%, p = 0.04) and retention (∼ 80%, p = 0.008), and a considerable decrease in urinary calcium excretion (∼ 40%, p = 0.01).The variations observed in bone markers reflected a higher bone turnover rate after the ID consumption. Conclusions: A varied diet based on Mediterranean diet patterns during adolescence greatly improves dietary calcium utilization, which may help to maximize the peak bone mass and prevent related diseases, such as osteoporosis.

Influence of Diets Rich in Maillard Reaction Products on Calcium Bioavailability. Assays in Male Adolescents and in Caco-2 Cells

The effects of the high intake of Maillard reaction products (MRP) on calcium availability in adolescents and across Caco-2 cell monolayers were examined. In a 2 week randomized two-period crossover trial, 18 male adolescents consumed two diets, named white diet (WD) and brown diet (BD), which were poor and rich in MRP, respectively. A 3 day balance was performed at the end of each period, and fasting blood samples were collected. Calcium solubility and absorption across Caco-2 cells were studied after the in vitro digestion of the diets. The in vitro assay showed similar solubility after the in vitro digestion and similar transport across Caco-2 cells. In accordance, calcium bioavailability in adolescents did not vary between the diets (%WD = 40.4 +/- 5.1, %BD = 38.2 +/- 3.6). Serum and urine biochemical parameters related to calcium status and bone metabolism remained unaltered. Only deoxypyridinoline values were significantly lower after consumption of the BD (13.0 +/- 1.1 compared to 18.3 +/- 2.1 nM/Mm Cr in the WD), possibly indicative of less efficient bone turnover during this period. As calcium acquired during adolescence is essential to maximize peak bone mass and to prevent osteoporosis, possible long-term effects of excessive MRP intake during this period warrant attention.

Use of Coffee Silverskin and Stevia to Improve the Formulation of Biscuits

Abstract Decreasing the amount of sugar added to biscuits is a good strategy to obtain a healthy product. However, a reduction in the quantity of sugar may affect its nutritional value and quality. The feasibility of the combined use of stevia and coffee silverskin for achieving healthier, nutritious and good quality biscuits has been investigated. Ten wheat four biscuit formulations were designed. Sucrose, maltitol and stevia were used as sweeteners and coffee silverskin was used as a natural colouring and as a source of dietary fbre. The quality of the biscuits was evaluated by measuring their moisture, thickness, breaking force and colour. Acrylamide (ACR) and hydroxymethylfurfural (HMF) contents were also determined in the interest of food safety. The quality and safety of the innovative biscuits was obtained by an analysis of the sugars, proteins, free amino acids, chlorogenic acid, overall antioxidant capacity and acrylamide after in vitro digestion. Only the stevia biscuits and those added with coffee silverskin extract and the solid residue recovered from the extraction process, were selected for that study. A comparison of the stevia formulated biscuits, with the stevia formula added with silverskin, showed that the added biscuits had a good nutritional quality and improved texture and colour.

Acrylamide in commercial potato crisps from Spanish market: Trends from 2004 to 2014 and assessment of the dietary exposure.

This research updates the acrylamide content of commercial potato crisps marketed in Spain with the aim to evaluate its trend since 2004. Two different batches of 40 potato crisps brands from 18 producers were analysed. Acrylamide content ranged from 108 to 2180 µg/kg, with an average value of 630 µg/kg and a median of 556 µg/kg. Data revealed a continuous decreased trend from 2004 to 2014. In 2014, potato crisps showed an average acrylamide content 14.6% lower than the previous report in 2009 and 57.6% lower than the first report in 2004. These data confirm the overall effectiveness in the mitigation strategies implemented by the Spanish industrial sector, although variations up to 80% were observed between a number of brands. However, 17.5% of the samples registered values higher than the indicative value recommended by European Commission for potato crisps. The dietary exposure of the Spanish population to this contaminant through potato crisps intake was estimated to be 0.035 µg/kg body weight/day. Although exposure has decreased over the last ten years, it is necessary to continue efforts to reduce acrylamide content in potato crisps since there is still margin for it.

Iron Nutrition in Adolescence

Adolescence is an important period of nutritional vulnerability due to increased dietary requirements for growth and development. Iron needs are elevated as a result of intensive growth and muscular development, which implies an increase in blood volume; thus, it is extremely important for the adolescents iron requirements to be met. Diet, therefore, must provide enough iron and, moreover, nutrients producing adequate iron bioavailability to favor element utilization and thus be sufficient for needs at this stage of life. Currently, many adolescents consume monotonous and unbalanced diets which may limit mineral intake and/or bioavailability, leading to iron deficiency and, consequently, to ferropenic anemia, a nutritional deficit of worldwide prevalence. Iron deficiency, apart from provoking important physiological repercussions, can adversely affect adolescents’ cognitive ability and behavior. Accordingly, promoting the consumption of a varied, adjusted, and balanced diet by adolescents will facilitate iron utilization, benefiting their health both at present and in adulthood. This review discusses how physiological changes during adolescence can cause iron requirements to increase. Consequently, it is important that diet should contribute an appropriate amount of this mineral and, moreover, with an adequate bioavailability to satisfy needs during this special period of life.

The beneficial effect of Mediterranean dietary patterns on dietary iron utilization in male adolescents aged 11–14 years

The effects of a diet based on Mediterranean patterns on iron bioavailability and iron status in adolescents were studied. The study was divided into two periods: basal period, in which 21 male adolescents consumed their habitual diet (basal diet); and nutritional intervention period, during which an experimental diet based on the Mediterranean model was consumed. Dietary iron utilization was studied by means of iron intake and iron output in faeces and urine, and iron status was analysed in fasting blood samples collected at the end of each period. No differences in total iron intake were found between diets, but consumption of the experimental diet increased iron absorption and retention compared with the basal diet. Biochemical parameters related to iron metabolism did not vary after the intervention period, although serum ferritin tended to increase. Therefore, a diet based on Mediterranean dietary patterns may improve dietary iron utilization during adolescence and may prevent iron deficiency.

Dietary calcium utilization among a group of spanish boys aged 11–14 years on their usual diets

Adolescence constitutes a period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. A pilot trial was performed to evaluate the dietary calcium utilization among a sample of Spanish boys on their usual diets, in which the calcium intake and consumption of dairy products were as well examined. Nutrient and food intake was recorded using a 24-h dietary recall and a 2-d food consumption record for 21 subjects aged 11–14 years. Dietary calcium utilization was assessed by means of calcium intake in food and calcium output in faeces and urine as measured by flame atomic absorption spectrophotometry. Overall intake of dairy products was 399.3±22.1 g/d, and the single most consumed item was milk (72% of the total). An inverse relationship was found between dairy product consumption at breakfast (55% of the total) and BMI (p=0.016, r=−0.5168). Dairy products contributed the majority of dietary calcium (66.9%). Mean calcium intake was 881.7±39.9 mg/d, 88% of the recommended value for Spanish adolescents. Net calcium absorption (271.7±51.7 mg/d) and retention (170.6±50.9 mg/d) seemed not to be sufficient to meet growth demands during puberty. The results shown that adolescents of the study absorbed 31% of dietary calcium and retained nearly 20% of the total intake, but dietary calcium intake and consumption of dairy products failed to meet recommended values. Optimizing calcium intake is of crucial importance among adolescents, to maximize calcium retention and to help prevent osteoporosis in later life.ResumenLa adolescencia constituye una etapa vulnerable desde el punto de vista nutricional, tanto por sus elevadas necesidades para el crecimiento y la maduración como por sus especiales hábitos alimentarios. Este trabajo supone un estudio piloto diseñado para evaluar la utilización del calcio dietético en un grupo de 21 chicos de 11–14 años que consumen su dieta habitual, examinando la ingesta de calcio y el consumo de productos lácteos. La ingesta alimentaria fue evaluada mediante un recordatorio de 24-h y un registro estimado de alimentos de 2 días. Para evaluar la utilización del calcio de la dieta se analizó la excreción en orina y heces mediante espectrofotometría de absorción atómica. La ingesta media de productos lácteos fue de 399,3±22,1 g/día, aportando el 66,9% del calcio total de la dieta y siendo la leche el producto más consumido (72% del total). Se encontró una correlación inversa entra el consumo de lácteos en el desayuno (55% del total) y el IMC (p=0,016, r=−5,168). La ingesta media de calcio fue de 881,7±39,9 mg/d, lo cual supone el 88% del valor recomendado para adolescentes españoles. Las cifras de absorción (271,7±51,7 mg/d) y retención (170,6±50,9 mg/d) de calcio parecieron insuficientes para satisfacer las demandas para el crecimiento durante la pubertad. Los resultados mostraron que los adolescentes del estudio absorbieron el 31% del calcio dietético y retuvieron casi el 20%, aunque ni la ingesta de calcio ni el consumo de productos lácteos alcanzaron las recomendaciones. Una ingesta adecuada de calcio y ayudar a prevenir la osteoporosis en la edad adulta.

Nickel levels in convenience and fast foods: In vitro study of the dialyzable fraction

Nickel presence was determined in 170 samples of 43 different convenience and fast foods widely consumed in Spain. Electrothermal atomic absorption spectrometry was used as analytical technique. Reliability of the procedure was checked. Ni levels ranged from 18.50 to 95.00 ng g(-1) (fresh weight of edible portion). The most elevated Ni concentrations were found in egg- and pork-based foods and in sauces but there is a high variability inside of each one of these foods. Ni content increases in products that contain spices and aromatic herbs, whole cereals, dry fruits, cheese and mushrooms. Mean Ni dialyzable fraction estimated by in vitro assays ranged from 4.50 to 7.75%. This study shows that the probability of exposure to health risks from these foods is overall small. However, the present findings are of potential use in food composition tables and to estimate the Ni dietary intake and tolerable intake levels in accordance with the current dietary habits.