Samara Joy Nielsen
University of North Carolina at Chapel Hill
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Samara Joy Nielsen.
The American Journal of Clinical Nutrition | 2013
Brian K. Kit; Tala Hi Fakhouri; Sohyun Park; Samara Joy Nielsen; Cynthia L. Ogden
BACKGROUND Reducing sugar-sweetened beverage (SSB) consumption is a recommended strategy to promote optimal health. OBJECTIVE The objective was to describe trends in SSB consumption among youth and adults in the United States. DESIGN We analyzed energy intake from SSBs among 22,367 youth aged 2-19 y and 29,133 adults aged ≥20 y who participated in a 24-h dietary recall as part of NHANES, a nationally representative sample of the US population with a cross-sectional design, between 1999 and 2010. SSBs included soda, fruit drinks, sports and energy drinks, sweetened coffee and tea, and other sweetened beverages. Patterns of SSB consumption, including location of consumption and meal occasion associated with consumption, were also examined. RESULTS In 2009-2010, youth consumed a mean (±SE) of 155 ± 7 kcal/d from SSBs, and adults consumed an age-adjusted mean (±SE) of 151 ± 5 kcal/d from SSBs--a decrease from 1999 to 2000 of 68 kcal/d and 45 kcal/d, respectively (P-trend < 0.001 for each). In 2009-2010, SSBs contributed 8.0% ± 0.4% and 6.9% ± 0.2% of daily energy intake among youth and adults, respectively, which reflected a decrease compared with 1999-2000 (P-trend < 0.001 for both). Decreases in SSB consumption, both in the home and away from home and also with both meals and snacks, occurred over the 12-y study duration (P-trend < 0.01 for each). CONCLUSION A decrease in SSB consumption among youth and adults in the United States was observed between 1999 and 2010.
Natural Product Research | 2007
Feras Q. Alali; Khaled Tawaha; Tamam El-Elimat; Maha Syouf; Mosa El-Fayad; Khaled Abulaila; Samara Joy Nielsen; William D. Wheaton; Joseph O. Falkinham; Nicholas H. Oberlies
As part of an International Cooperative Biodiversity Groups (ICBG) program to study Jordans biodiversity, the relative levels of antioxidant activity and the total phenolic content of aqueous and methanolic extracts of a total of 95 plant species, all of Jordanian origin and those collected at random, have been measured. The total phenolic content of aqueous and methanolic extracts of the investigated plant species ranged from 4.4 to 78.3 mg and from 2.1 to 52.8 mg gallic acid equivalents g−1 dry weight, respectively, while the total antioxidant capacity ranged from 20.0 to 916.7 and from 15.1 to 915.6 μmol Trolox equivalents g−1 dry weight, respectively. Based on this collection, approximately 5% of assayed plants showed high levels of antioxidant activity. There was a significant linear correlation between antioxidant activity and total phenolic content for aqueous and methanolic extracts, suggesting that phenolic compounds were the predominant antioxidant components in the investigated plant species. Interestingly, a few of the collected plants had high-antioxidant activity yet “low” phenolic content includes Ceratonia siliqua and Viscum cruciatum. These plants may serve as sources of antioxidants with new chemotypes.
The American Journal of Clinical Nutrition | 2014
Samara Joy Nielsen; Brian K. Kit; Yutaka Aoki; Cynthia L. Ogden
BACKGROUND Seafood is part of a healthy diet, but seafood can also contain methyl mercury-a neurotoxin. OBJECTIVE The objective was to describe seafood consumption in US adults and to explore the relation between seafood consumption and blood mercury. DESIGN Seafood consumption, obtained from a food-frequency questionnaire, and blood mercury data were available for 10,673 adults who participated in the 2007-2010 NHANES-a cross-sectional nationally representative sample of the US population. Seafood consumption was categorized by type (fish or shellfish) and by frequency of consumption (0, 1-2, 3-4, or ≥5 times/mo). Linear trends in geometric mean blood mercury concentrations by frequency of seafood consumption were tested. Logistic regression analyses examined the odds of blood mercury concentrations ≥5.8 μg/L (as identified by the National Research Council) based on frequency of the specific type of seafood consumed (included in the model as continuous variables) adjusted for sex, age, and race/Hispanic origin. RESULTS In 2007-2010, 83.0% ± 0.7% (±SE) of adults consumed seafood in the preceding month. In adults consuming seafood, the blood mercury concentration increased as the frequency of seafood consumption increased (P < 0.001). In 2007-2010, 4.6% ± 0.39% of adults had blood mercury concentrations ≥5.8 μg/L. Results of the logistic regression on blood mercury concentrations ≥5.8 μg/L showed no association with shrimp (P = 0.21) or crab (P = 0.48) consumption and a highly significant positive association with consumption of high-mercury fish (adjusted OR per unit monthly consumption: 4.58; 95% CI: 2.44, 8.62; P < 0.001), tuna (adjusted OR: 1.14; 95% CI: 1.10, 1.17; P < 0.001), salmon (adjusted OR: 1.14; 95% CI: 1.09, 1.20; P < 0.001), and other seafood (adjusted OR: 1.12; 95% CI: 1.08, 1.15; P < 0.001). CONCLUSION Most US adults consume seafood, and the blood mercury concentration is associated with the consumption of tuna, salmon, high-mercury fish, and other seafood.
Pediatrics | 2015
Kirsten A. Herrick; Lauren M. Rossen; Samara Joy Nielsen; Amy M. Branum; Cynthia L. Ogden
OBJECTIVES: To describe the contribution of whole fruit, including discrete types of fruit, to total fruit consumption and to investigate differences in consumption by sociodemographic characteristics. METHODS: We analyzed data from 3129 youth aged 2 to 19 years from the National Health and Nutrition Examination Survey, 2011 to 2012. Using the Food Patterns Equivalents Database and the What We Eat in America 150 food groups, we calculated the contribution of whole fruit, 100% fruit juices, mixed fruit dishes, and 12 discrete fruit and fruit juices to total fruit consumption. We examined differences by age, gender, race and Hispanic origin, and poverty status. RESULTS: Nearly 90% of total fruit intake came from whole fruits (53%) and 100% fruit juices (34%) among youth aged 2 to 19 years. Apples, apple juice, citrus juice, and bananas were responsible for almost half of total fruit consumption. Apples accounted for 18.9% of fruit intake. Differences by age were predominately between youth aged 2 to 5 years and 6 to 11 years. For example, apples contributed a larger percentage of total fruit intake among youth 6 to 11 years old (22.4%) than among youth 2 to 5 years old (14.6%), but apple juice contributed a smaller percentage (8.8% vs 16.8%), P < .05. There were differences by race and Hispanic origin in intake of citrus fruits, berries, melons, dried fruit, and citrus juices and other fruit juices. CONCLUSIONS: These findings provide insight into what fruits US youth are consuming and sociodemographic factors that may influence consumption.
Journal of Nutrition | 2015
Samara Joy Nielsen; Yutaka Aoki; Brian K. Kit; Cynthia L. Ogden
BACKGROUND Consuming seafood has health benefits, but seafood can also contain methylmercury, a neurotoxicant. Exposure to methylmercury affects children at different stages of brain development, including during adolescence. OBJECTIVE The objective was to examine seafood consumption and blood mercury concentrations in US youth. METHODS In the 2009-2012 NHANES, a cross-sectional nationally representative sample of the US population, seafood consumption in the past 30 d and blood mercury concentrations on the day of examination were collected from 5656 youth aged 1-19 y. Log-linear regression was used to examine the association between frequency of specific seafood consumption and blood mercury concentration, adjusting for race/Hispanic origin, sex, and age. RESULTS In 2009-2012, 62.4% ± 1.4% (percent ± SE) of youth consumed any seafood in the preceding month; 38.4% ± 1.4% and 48.5% ± 1.5% reported consuming shellfish and fish, respectively. In 2009-2012, the geometric mean blood mercury concentration was 0.50 ± 0.02 μg/L among seafood consumers and 0.27 ± 0.01 μg/L among those who did not consume seafood. Less than 0.5% of youth had blood mercury concentrations ≥5.8 μg/L. In adjusted log-linear regression analysis, no significant associations were observed between frequency of breaded fish or catfish consumption and blood mercury concentrations, but frequency of consuming certain seafood types had significant positive association with blood mercury concentrations: high-mercury fish (swordfish and shark) [exponentiated β coefficient (expβ): 2.40; 95% CI: 1.23, 4.68]; salmon (expβ: 1.41; 95% CI: 1.26, 1.55); tuna (expβ: 1.38; 95% CI: 1.29, 1.45); crabs (expβ: 1.35; 95% CI: 1.17, 1.55); shrimp (expβ: 1.12; 95% CI: 1.05, 1.20), and all other seafood (expβ: 1.23; 95% CI: 1.17, 1.32). Age-stratified log-linear regression analyses produced similar results. CONCLUSION Few US youth have blood mercury concentrations ≥5.8 μg/L, although more than half of US youth consumed seafood in the past month.
The American Journal of Clinical Nutrition | 2004
George A. Bray; Samara Joy Nielsen; Barry M. Popkin
JAMA | 2003
Samara Joy Nielsen; Barry M. Popkin
American Journal of Preventive Medicine | 2004
Samara Joy Nielsen; Barry M. Popkin
Obesity Research | 2002
Samara Joy Nielsen; Anna Maria Siega-Riz; Barry M. Popkin
Preventive Medicine | 2002
Samara Joy Nielsen; Anna Maria Siega-Riz; Barry M. Popkin