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Burri B.J.,Western Human Nutrition Research Center | Burri B.J.,University of California at Davis | Nguyen T.,Western Human Nutrition Research Center | Neidlinger T.R.,Western Human Nutrition Research Center
Nutrition | Year: 2010

Objective: Studies show low correlations between dietary intake and serum concentrations of lycopene, which make it difficult to assess the effectiveness of dietary interventions with this phytonutrient. We hypothesized that 1) combining food-frequency questionnaires (FFQs) and 3-d diet records (3D-DRs) by the triads method would improve the validity of this relation and 2) correcting dietary information for differences in lycopene absorption from food matrices would further improve validity. Methods: We measured dietary intakes of lycopene from 49 adults by 3D-DR and FFQ. Serum lycopene was measured by high-performance liquid chromatography with diode array detection. Cholesterol and triacylglycerol concentrations were measured spectrophotometrically. Lycopene-containing foods were given absorption factors based on literature and laboratory values. Associations between dietary and serum lycopene were modeled using multiple regression. The triads method was used for validation of relations among FFQ, 3D-DR, and serum lycopene. Results: Raw data showed low correlations between dietary and serum lycopene (r = +0.15 for 3D-DR, +0.35 for FFQ). Mathematical modeling showed that the 3D-DR and FFQ methods must be used to collect accurate dietary information for lycopene. Validity coefficients calculated by the triads method were +0.34 for 3D-DR and +0.78 for FFQ. Correcting for absorption increased the validity coefficient to +0.72 for 3D-DR and from +0.45 to +0.66 for serum lycopene. Conclusion: The relation between dietary intake and serum concentrations of lycopene and other carotenoids can be improved by collecting 3D-DR and FFQ data and by adjusting dietary information for nutrient absorption. Source

Roman M.J.,University of California at Davis | Burri B.J.,Western Human Nutrition Research Center | Singh R.P.,University of California at Davis
Journal of Agricultural and Food Chemistry | Year: 2012

The objective of this study was to determine the release and bioaccessibility of β-carotene from fortified almond butter using in vitro digestion models. Two types of fortifiers were investigated: β-carotene oil (oil) and whey protein isolate (WPI)-alginate-chitosan capsules containing β-carotene oil (capsule). Shaking water bath and Human Gastric Simulator (HGS) digestion models assessed the impact of gastric peristalsis on the release of β-carotene. Bioaccessibility of β-carotene was measured as percent recovered from the micelle fraction. There was greater release of β-carotene from oil fortified almond butter in the HGS model (87.1%) due to peristalsis than the shaking water bath model (51.0%). More β-carotene was released from capsule fortified almond butter during intestinal digestion. However, more β-carotene was recovered from the micelle fraction of oil fortified almond butter. These results suggest that a WPI-alginate-chitosan capsule coating may inhibit the bioaccessibility of β-carotene from fortified almond butter. © 2012 American Chemical Society. Source

Rezvani R.,Laval University | Cianflone K.,Laval University | McGahan J.P.,University of California at Davis | Berglund L.,University of California at Davis | And 3 more authors.
Obesity | Year: 2013

Objective The effects of fructose and glucose consumption on plasma acylation stimulating protein (ASP), adiponectin, and leptin concentrations relative to energy intake, body weight, adiposity, circulating triglycerides, and insulin sensitivity were determined. Design and Methods Thirty two overweight/obese adults consumed glucose-or fructose-sweetened beverages (25% energy requirement) with their ad libitum diets for 8 weeks, followed by sweetened beverage consumption for 2 weeks with a standardized, energy-balanced diet. Plasma variables were measured at baseline, 2, 8, and 10 weeks, and body adiposity and insulin sensitivity at baseline and 10 weeks. Results Fasting and postprandial ASP concentrations increased at 2 and/or 8 weeks. ASP increases correlated with changes in late-evening triglyceride concentrations. At 10 weeks, fasting adiponectin levels decreased in both groups, and decreases were inversely associated with baseline intra-abdominal fat volume. Sugar consumption increased fasting leptin concentrations; increases were associated with body weight changes. The 24-h leptin profiles increased during glucose consumption and decreased during fructose consumption. These changes correlated with changes of 24-h insulin levels. Conclusions The consumption of fructose and glucose beverages induced changes in plasma concentrations of ASP, adiponectin, and leptin. Further study is required to determine if these changes contribute to the metabolic dysfunction observed during fructose consumption. Copyright © 2013 The Obesity Society. Source

Stanhope K.L.,University of California at Davis | Bremer A.A.,University of California at Davis | Bremer A.A.,Vanderbilt University | Medici V.,University of California at Davis | And 11 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2011

Context: The American Heart Association Nutrition Committee recommends women and men consume no more than 100 and 150 kcal of added sugar per day, respectively, whereas the Dietary Guidelines for Americans, 2010, suggests a maximal added sugar intake of 25% or less of total energy. Objective: To address this discrepancy, we compared the effects of consuming glucose, fructose, or high-fructose corn syrup (HFCS) at 25% of energy requirements (E) on risk factors for cardiovascular disease. Participants, Design and Setting, and Intervention: Forty-eight adults (aged 18-40 yr; body mass index 18-35 kg/m 2) resided at the Clinical Research Center for 3.5 d of baseline testing while consuming energy-balanced diets containing55%E complex carbohydrate. For 12 outpatient days, they consumed usual ad libitum diets along with three servings per day of glucose, fructose, or HFCS-sweetened beverages (n = 16/group), which provided 25% E requirements. Subjects then consumed energy-balanced diets containing 25% E sugar-sweetened beverages/30% E complex carbohydrate during 3.5 d of inpatient intervention testing. Main Outcome Measures: Twenty-four-hour triglyceride area under the curve, fasting plasma low-density lipoprotein (LDL), and apolipoprotein B (apoB) concentrations were measured. Results: Twenty-four-hour triglyceride area under the curve was increased compared with baseline during consumption of fructose (+4.7 ± 1.2 mmol/liter x 24 h, P = 0.0032) and HFCS (+1.8 ± 1.4 mmol/liter x 24 h, P = 0.035) but not glucose (-1.9 ± 0.9 mmol/liter x 24 h, P = 0.14). Fasting LDL and apoB concentrations were increased during consumption of fructose (LDL: +0.29 ± 0.082 mmol/liter, P = 0.0023; apoB: +0.093 ± 0.022 g/liter, P = 0.0005) and HFCS (LDL: +0.42 ± 0.11 mmol/liter, P < 0.0001; apoB: +0.12 ± 0.031 g/liter, P < 0.0001) but not glucose (LDL: +0.012 ± 0.071 mmol/liter, P = 0.86; apoB: +0.0097 ± 0.019 g/liter, P = 0.90). Conclusions: Consumption of HFCS-sweetened beverages for 2 wk at 25% E increased risk factors for cardiovascular disease comparably with fructose and more than glucose in young adults. Copyright © 2011 by The Endocrine Society. Source

Turner T.,University of California at Davis | Turner T.,Western Human Nutrition Research Center | Burri B.J.,University of California at Davis | Burri B.J.,Western Human Nutrition Research Center
Chromatographia | Year: 2012

Vitamin A deficiency continues to be a major public health concern in the developing world effecting over 200 million people. Interventions including carotenoid- rich fruits and vegetables, containing α- and β-carotene, and β-cryptoxanthin, are being tested for their potential to alleviate vitamin A deficiency in several countries. Thus, there is a need for a faster isocratic reverse-phase high pressure liquid chromatography (HPLC) method than the methods currently available. Efficient extraction procedures for biological samples are also valuable to save time, materials, and cost. We developed an HPLC method and compared several extraction methods for carotenoids, retinoids, and vitamin E in plasma and human breast milk. The method uses an Agilent 1100 system equipped with a Waters Spherisorb ODS2 column (3 × 125 mm 3 μm) and similar guard column (ThermoScientific ODS2 3 × 20 mm 3 μm). Mobile phase of 7:2:1 acetonitrile:dichloromethane: methanol was run at 0.5 mL min -1, and run times were complete in approximately 8 min. This rapid method uses little solvent and provides excellent results in the analysis of these fat-soluble nutrients. Analyte measurements were repeatable using standards and plasma and were accurate compared to NIST certified and reference serum values. The validated HPLC method was applied to the analysis of plasma samples from a vitamin A intervention study. © 2012 Springer-Verlag. Source

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