Ada L. Garcia

Arabinoxylan consumption decreases postprandial serum glucose, serum insulin and plasma total ghrelin response in subjects with impaired glucose tolerance

Objective:Arabinoxylan (AX) consumption is associated with metabolic improvement during diabetes and with modulation of ghrelin, an orexigenic gut hormone. The effect of AX consumption on ghrelin secretion in disturbed metabolic states is unknown. Therefore, we investigated the postprandial responses to AX consumption of serum glucose, insulin and triglycerides and plasma total and acylated ghrelin in subjects with impaired glucose tolerance (IGT).Design:Randomized, single-blind, controlled, crossover intervention trial.Subjects:Seven female and four male adults with IGT, aged 55.5 years, and body mass index (BMI) 30.1 kg/m2.Intervention:Subjects received either placebo or 15 g AX supplement for 6 weeks with a 6-week washout period in-between.Main outcome measurements:Postprandial responses of serum glucose, insulin and triglycerides, and plasma total and acylated ghrelin after a liquid meal challenge test (LMCT) measured at the beginning and at the end of the dietary intervention at −20, −5, 0, 15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min.Results:After LMCT, AX consumption resulted in lower postprandial responses in serum glucose, insulin and triglycerides (P<0.05). Compared to placebo, total plasma ghrelin was also reduced by 42±8 pg/ml (P<0.001) after AX consumption with no difference in plasma acylated ghrelin.Conclusion:AX consumption improved postprandial metabolic responses after an LMCT in subjects with IGT and reduced total ghrelin response. However, acylated ghrelin responses were unchanged, suggesting that the acylated ghrelin-mediated orexigenic regulation is not improved as only total plasma ghrelin decreased.Sponsorship:Federal Ministry of Education and Research Germany (PTJ-BIO/0313042C).

Validation of a simplified physical activity record by doubly labeled water technique

INTRODUCTION:For obtaining reliable information about physical activity in epidemiological studies, validated and easy-to-use instruments are required. Therefore, a new simplified physical activity record based on 15-min recording intervals was developed and validated.SUBJECTS:Nonobese volunteers (n=31).MEASUREMENTS:Physical activity was recorded over a 7-day period without detailed instructions. Energy expenditure was calculated (EEsPAR) and compared to energy expenditure measured by doubly labelled water technique (EEDLW).RESULTS:A good agreement between EEsPAR (12.1±3.0) and EEDLW (11.7±3.3) with a mean difference of 0.33±1.55 MJ (r=0.880, P<0.001) was observed. The absolute difference between EEsPAR and EEDLW was <10% in 65% of the subjects. The difference between EEsPAR and EEDLW was independent of gender, age, body weight, and body mass index. A weak positive association between the difference and total body fat was observed (r=0.618, P<0.001), suggesting a slight tendency to overestimate EEsPAR with increasing total body fat.CONCLUSION:The new simplified physical activity protocol needs no detailed instructions, provides valid estimates of physical activity in nonobese free-living adults and can be used in epidemiological studies to assess total daily energy expenditure and physical activity level.

Carob pulp preparation rich in insoluble dietary fibre and polyphenols increases plasma glucose and serum insulin responses in combination with a glucose load in humans

Dietary fibre consumption is associated with improved glucose homeostasis. In contrast, dietary polyphenols have been suggested to exert both beneficial and detrimental effects on glucose and insulin metabolism. Recently, we reported that a polyphenol-rich insoluble dietary fibre preparation from carob pulp (carob fibre) resulted in lower postprandial acylated ghrelin levels after a liquid meal challenge test compared with a control meal without supplementation. The effects may, however, differ when a different food matrix is used. Thus, we investigated the effects of carob fibre on glucose, insulin and ghrelin responses in healthy humans in combination with a glucose load. In a randomized single-blind cross-over study involving twenty healthy subjects (aged 22-62 years), plasma glucose, total and acylated ghrelin, and serum insulin were repeatedly assessed before and after the ingestion of 200 ml water with 50 g glucose and 0, 5, 10 or 20 g carob fibre over a period of 180 min. The intake of 5 and 10 g carob fibre increased the plasma glucose by 47 % and 64 % (P < 0.001), and serum insulin by 19.9 and 24.8 % (P < 0.001), compared with the control. Plasma acylated ghrelin concentrations did not change significantly after the consumption of carob-enriched glucose solution. Total ghrelin decreased only after 10 g carob fibre (P < 0.001) compared with control. In conclusion, we showed that polyphenol-rich carob fibre, administered within a water-glucose solution, increases postprandial glucose and insulin responses, suggesting a deterioration in glycaemic control.

Serum resistin increases in a postprandial state during liquid meal challenge test in healthy human subjects

The role of resistin in humans is controversial although resistin has been linked to atherosclerotic and inflammatory processes. In rodents, resistin expression is suppressed after food restriction while central administration of resistin promotes short-term satiety. However, the nature of postprandial responses in circulating resistin in humans is unknown. Therefore, we investigated postprandial resistin concentrations in a pilot study in 19 healthy subjects and 19 controls matched for age and body mass index (BMI). Serum resistin, insulin and non-esterified fatty acids (NEFA) concentrations as well as plasma glucose and triglycerides were repeatedly assessed before and after ingestion of an isocaloric standardized liquid meal during a 300 min period. After consumption of liquid meal, serum resistin levels increased compared to fasting control (p=0.037). Postprandial plasma glucose and serum insulin increased (p<0.001) with lower glucose responses in females (p=0.001) and lower insulin responses in males (p=0.012). Plasma triglycerides increased and serum NEFA decreased with similar gender responses (p=0.025 and p<0.001, respectively). Serum resistin was not correlated to glucose, insulin, triglyceride, and NEFA responses to liquid meal challenge tests. The present data suggest that serum resistin increases postprandially in healthy humans. Additional studies are needed to elucidate normal 24-h daytime profiles in humans and differential response of serum resistin to macronutrient composition of meals.

Retinoid‐ and carotenoid‐enriched diets influence the ontogenesis of the immune system in mice

Vitamin A (VA) has been identified as an important factor for the development of the immune system, especially during ontogenesis. It has been shown that antibody secretion and proliferation of lymphocyte populations depend on retinoids. In the present study we investigated the influence of a base VA diet and diets enriched with VA, β‐carotene and lycopene, on the ontogenesis of the immune system in mice. We examined the absolute and relative concentrations of splenic B lymphocytes (CD45R/B220), T lymphocytes (CD3+) and their subpopulations (CD4+ and CD8+), and measured serum immunoglobulin G (IgG) concentrations in the offspring of supplemented dams at different ages (1, 3, 5, 7, 14, 21 and 65 days). The experimental diets resulted in higher numbers of T and B lymphocytes after VA and carotenoid enrichment, when compared, at various time‐points, with the base diet. Higher values of total serum IgG were found in the β‐carotene‐enriched diet group on day 7. On days 7 and 14, the enriched diets induced significant alterations in the percentages and total numbers of splenic lymphocytes in comparison to the base diet. Our results confirm that supplementation with VA and carotenoids affect the immune‐cell function during ontogenesis and suggest a possible role of these nutritional factors on the development of the immune system.

Nutritional content of infant commercial weaning foods in the UK

Background and aims Health professionals are frequently asked to advise on aspects of complementary feeding. This study aimed to describe the types of commercial infant foods available in the UK and provide an overview of their taste, texture and nutritional content in terms of energy, protein, carbohydrates, fat, sugar, iron, sodium and calcium. Method All infant foods produced by four main UK manufacturers and two more specialist suppliers were identified during October 2010–February 2011. Nutritional information for each product was collected from manufacturers’ websites, products in store and via direct email enquiry. Results Of the 479 products identified in this study 364 (79%) were ready-made spoonable foods; 44% (201) were aimed at infants from 4 months, and 65% of these were sweet foods. The mean (SD) energy content of ready-made spoonable foods was 282 (59) kJ per 100 g, almost identical to breast milk (283(16) kJ per 100 g). Similar spoonable family foods were more nutrient dense than commercial foods. Commercial finger foods were more energy dense, but had very high sugar content. Conclusions The UK infant food market mainly supplies sweet, soft, spoonable foods targeted from age 4 months. The majority of products had energy content similar to breast milk and would not serve the intended purpose of enhancing the nutrient density and diversity of taste and texture in infants’ diets.

An easy-to-use semiquantitative food record validated for energy intake by using doubly labelled water technique

Background:Estimating dietary intake is important for both epidemiological and clinical studies, but often lacks accuracy.Objective:To investigate the accuracy and validity of energy intake estimated by an easy-to-use semiquantitative food record (EISQFR) compared to total energy expenditure (TEE) estimated by doubly labelled water technique (EEDLW).Design:TEE was measured in 29 nonobese subjects using the doubly labelled water method over a period of 14 days. Within this period, subjects reported their food consumption by a newly developed semiquantitative food record for 4 consecutive days. Energy intake was calculated using the German Food Code and Nutrition Data Base BLS II.3.Results:A good correlation was observed between EISQFR and EEDLW (r=0.685, P<0.001). The mean difference between EISQFR and EEDLW was −1.7±2.6 MJ/day (−14±21%, P=0.002). An underestimation of EISQFR <10% was observed in nine subjects (31%), of 10–20% in six subjects (21%), and of >20% in nine subjects (31%). In five subjects (17%), an overestimation of EISQFR was observed.Conclusions:The easy-to-use semiquantitative food record provided good estimates of EI in free-living and nonobese adults without prior detailed verbal instructions. The presented food record has limitations regarding accuracy at the individual level.

Lycopene-derived bioactive retinoic acid receptors/retinoid-X receptors-activating metabolites may be relevant for lycopene's anti-cancer potential

Dietary consumption of tomato products and especially the red tomato pigment lycopene has been associated with lower risk of cancer. New evidence is emerging toward metabolic pathways mediating the anti-cancer activities of lycopene. In this review, we explore associations between tomatoes and lycopene intake and cancer and relate this to the metabolic activation pathways of lycopene via carotene oxygenases and further carotenoid/retinoid-metabolizing enzymes to apo-lycopenoids. Several of these apo-lycopenoids have already been identified but up to date no direct connection between lycopene metabolism and apo-lycopenoids mediated receptor activation pathways has been established. Retinoic acid receptors/retinoid-X receptors activation pathways in particular, may be mediated via lycopene metabolites that are related to retinoic acids. Various studies have shown an association between lower concentration of insulin-like growth factor-1 upon lycopene treatment, cancer incidences, and retinoid-mediated signaling. In this review, we interrelate tomato/lycopene ingestion and cancer incidence, with metabolic activation of lycopene and retinoid-mediated signaling. The aim is to discuss a potential mechanism to explain lycopene related anti-cancer activities by modulation of insulin-like growth factor-1 concentrations via lycopene metabolite activation of retinoid-mediated signaling.

Evaluation of a cooking skills programme in parents of young children – a longitudinal study

OBJECTIVE To evaluate longitudinally the effectiveness of a cooking programme on self-reported confidence about cooking skills and food consumption patterns in parents of young children. DESIGN An evaluation of cooking programmes delivered by National Health Service (NHS) community food workers using a single group pre-test/post-test repeated measures design. A shortened version of a validated questionnaire at baseline, post intervention and 1-year follow-up determined confidence in cooking using basic ingredients, following a simple recipe, tasting new foods, preparing and cooking new foods on consumption of ready meals, vegetables and fruit. SETTING Deprived communities in Ayrshire and Arran, Scotland. SUBJECTS Parents of nursery age children, 97 % were female and <45 years old. RESULTS One hundred and two participants had completed baseline and post-intervention questionnaires. Forty-four participants contacted by telephone completed a follow-up questionnaire. In participants who completed all questionnaires (n 44), median confidence in four aspects of cooking increased significantly from baseline to post intervention (P < 0·001) but was retained at 1-year follow-up only for following a simple recipe and preparing and cooking new foods. Improved food consumption patterns were reported from baseline to post intervention (ready-meal consumption reduced from 2-4 times/week to 1 time/week, P < 0·001; vegetable consumption increased from 5-6 times/week to 1 time/d, P < 0·001; fruit consumption increased from 5-6 times/week to 1 time/d, P < 0·001) and remained at 1-year follow-up. CONCLUSIONS The cooking programmes appeared to improve cooking confidence and food consumption patterns in the target group and some of these changes were retained after 1 year.

Identification of Plasma and Urinary Metabolites and Catabolites Derived from Orange Juice (Poly)phenols: Analysis by High-Performance Liquid Chromatography–High-Resolution Mass Spectrometry

Orange juice is a rich source of (poly)phenols, in particular, the flavanones hesperetin-7-O-rutinoside and naringenin-7-O-rutinoside. Following the acute consumption of 500 mL of orange juice containing 398 μmol of (poly)phenols by 12 volunteers, 0-24 h plasma and urine samples were analyzed by targeted high-performance liquid chromatography-high-resolution mass spectrometry in order to identify flavanone metabolites and phenolic acid and aromatic catabolites. A total of 19 flavanone metabolites-comprising di-O-glucuronide, O-glucuronide, O-glucuronyl-sulfate, and sulfate derivatives of hesperetin, naringenin, and eriodictyol-and 65 microbial-derived phenolic catabolites, such as phenylpropanoid, phenylpropionic, phenylacetic, benzoic, and hydroxycarboxylic acids and benzenetriol and benzoylglycine derivatives, including free phenolics and phase II sulfate, glucuronide, and methyl metabolites, were identified or partially identified in plasma and/or urine samples. The data obtained provide a detailed evaluation of the fate of orange juice (poly)phenols as they pass through the gastrointestinal tract and are absorbed into the circulatory system prior to renal excretion. Potential pathways for these conversions are proposed.