Karen Ringwald-Smith

Dr. Karen Ringwald-Smith


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 May 2013 in Nutrients
Verified
Journal Article
Open access
PDF file
EVEszter Völgyi
Eszter Völgyi
KCKecia Carroll
Kecia Carroll
MHMarion E. Hare
Marion E. Hare
KRKaren Ringwald-Smith
Karen Ringwald-Smith
CPChandrika Piyathilake
Chandrika Piyathilake
FTFrances A. Tylavsky
Frances A. Tylavsky
Dietary patterns are sensitive to differences across socio-economic strata or cultural habits and may impact programing of diseases in later life. The purpose of this study was to identify distinct dietary patterns during pregnancy in the Mid-South using factor analysis. Furthermore, we aimed to analyze the differences in the food groups and in macro- and micronutrients among the different food patterns. The study was a cross-sectional analysis of 1155 pregnant women (mean age 26.5 ± 5.4 years; 62% African American, 35% Caucasian, 3% Other; and pre-pregnancy BMI 27.6 ± 7.5 kg/m2). Using food frequency questionnaire data collected from participants in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study between 16 and 28 weeks of gestation, dietary patterns were identified using factor analysis. Three major dietary patterns, namely, Healthy, Processed, and US Southern were identified among pregnant women from the Mid-South. Further analysis of the three main patterns revealed four mixed dietary patterns, i.e., Healthy-Processed, Healthy-US Southern, Processed-US Southern, and overall Mixed. These dietary patterns were different (p < 0.001) from each other in almost all the food items, macro- and micro nutrients and aligned across socioeconomic and racial groups. Our study describes unique dietary patterns in the Mid-South, consumed by a cohort of women enrolled in a prospective study examining the association of maternal nutritional factors during pregnancy that are known to affect brain and cognitive development by age 3.

18 May 2021 in Journal of Pediatric Hematology/Oncology
Verified
Journal Article
Closed access
KRKaren Ringwald-Smith
Karen Ringwald-Smith
RHRachel Rdn Hill
Rachel Rdn Hill
LELisa Ms Evanoff
Lisa Ms Evanoff
JMJenna Ms Martin
Jenna Ms Martin
NSNancy Ms Sacks
Nancy Ms Sacks
Nutritional problems are common in pediatric oncology due to the side effects of the disease and treatment. Nutrition intervention can be challenging, and little is known about the current clinical practice of registered dietitian nutritionists. An online questionnaire emailed to members of the pediatric, oncology nutrition, and clinical manager practice groups of the Academy of Nutrition and Dietetics, consisted of items related to current nutrition practice. Our questionnaire results suggest that the field of pediatric oncology is employed with relatively new dietitians (62% had <5 y of experience). Many registered dietitian nutritionists (60%) are providing care across the cancer care continuum (standard therapy, transplant, and survivorship) versus specializing in a particular area. Approximately half (52%) felt that their center had inadequate staffing, many reporting little in the outpatient setting. Barriers to providing optimal patient care included inadequate staffing, lack of time for research initiatives, and lack of evidence-based guidelines. Future studies should determine follow-up guidelines and appropriate staffing ratios for nutrition care in pediatric oncology. Approaches should be developed to support less experienced dietitians. Collaboration between dietitians at different facilities will likely be key in developing essential evidence-informed guidelines.

14 June 2023 in Nutrition in Clinical Practice
Verified
Journal Article
Closed access
KRKaren Ringwald-Smith
Karen Ringwald-Smith
HHHayley Hillman
Hayley Hillman
KGKristy Gibbons
Kristy Gibbons
RERebecca Epperly
Rebecca Epperly

2 February 2018 in Nutrition in Clinical Practice
Verified
Journal Article
Closed access
PDF file
KRKaren Ringwald-Smith
Karen Ringwald-Smith
AHAshley Hobar
Ashley Hobar
CFCasey Flowers
Casey Flowers
KBKatie Badgett
Katie Badgett
RWRuth Williams‐Hooker
Ruth Williams‐Hooker
BMBelinda N Mandrell
Belinda N Mandrell

19 September 2022 in Biomedicines
Verified
Journal Article
Open access
PDF file
NPNehali D. Patel
Nehali D. Patel
RPRhiannon Penkert
Rhiannon Penkert
RSRobert E. Sealy
Robert E. Sealy
SSSherri L. Lynn Surman
Sherri L. Lynn Surman
BJBart G Jones
Bart G Jones
JHJulia Hurwitz
Julia Hurwitz
Healthy pediatric immune responses depend on adequate vitamin A and D levels. Relationships between solar ultraviolet B (UVB) radiation and vitamin D are well understood, while relationships between sunlight, vitamin A, and its serum escort, retinol binding protein (RBP), are not. A pediatric clinical study enrolled 2–8-year-old children at various times between September 2016 and March 2017, inclusive, in Memphis, Tennessee. A serum sample from each child was then assayed to examine the influence of season on vitamin levels. We found that RBP and RBP/retinol molar ratios decreased in winter months and RBP/retinol ratios correlated positively with the average daily sunlight hours per month. A food frequency questionnaire given to parents/guardians indicated a shift in dietary intake from plant-based foods to animal-based foods by children between winter and spring months. This translated to higher retinol and zinc (integral to RBP–transthyretin–retinol complexes) in the spring, perhaps explaining the seasonal influence on RBP/retinol. RBP and retinol were associated positively with IgG/IgM and IgA/IgM ratios. RBP and retinol, but not 25(OH)D, also correlated positively with influenza virus-specific antibodies. Retinol correlated negatively, while 25(OH)D correlated positively, with certain serum cytokine/chemokine levels. Significant differences in 25(OH)D, immunoglobulin ratios, and cytokines/chemokines were observed between black and white children. In sum, seasonal changes in dietary foods rich in retinol and zinc may have influenced RBP levels, which in turn influenced innate and adaptive immune responses. Results encourage routine monitoring and reporting of season, RBP, and vitamin levels in future clinical studies, as seasons may affect sunlight exposures, diet, vitamin levels, and immune protection against infectious disease.

7 April 2025 in Biomolecules
Verified
Journal Article
Open access
PDF file
NPNehali D. Patel
Nehali D. Patel
SSSherri L. Lynn Surman
Sherri L. Lynn Surman
BJBart G Jones
Bart G Jones
RPRhiannon Penkert
Rhiannon Penkert
KRKaren Ringwald-Smith
Karen Ringwald-Smith
JHJulia Hurwitz
Julia Hurwitz
Previous studies have shown that high-dose vitamin supplements can improve vaccine-induced immune responses and pathogen protection in the context of vitamin deficiencies. To further elucidate the influence of vitamin supplements on immune responses toward pediatric vaccines, we performed a randomized controlled clinical trial (PCVIT) of 20 healthy children 1–4 years of age in Memphis, Tennessee. Study participants received a booster vaccine for pneumococcus and a primary vaccine for hepatitis A virus with or without a high-dose, oral, liquid supplement of 10,000 IU retinyl palmitate. We found that the children enrolled in PCVIT had higher baseline vitamin levels than previously described older children and adults living in Memphis. Only one child in PCVIT had a serum retinol level of less than 0.3 µg/mL. The children frequently consumed milk and baby foods that were likely vitamin-fortified, providing an explanation for the relatively high vitamin levels. Most children in PCVIT responded well to pneumococcus and hepatitis A vaccines by pathogen-specific antibody upregulation. The one child with a serum retinol level below 0.3 µg/mL did not receive a vitamin supplement and exhibited the lowest fold-change in antibody responses toward pneumococcal serotypes. A correlation matrix encompassing demographics, vitamin levels, vaccine-induced immune responses, C-reactive protein, and total serum immunoglobulin isotypes, including IgG2 and IgA, identified variables associated with vaccination outcomes. Perhaps because children were predominantly retinol-sufficient at baseline, the high-dose vitamin A supplement exhibited no benefit to vaccine-induced immune responses. In fact, when vitamin supplemented and vitamin unsupplemented groups were compared among participants with the highest baseline retinol levels, there was a trend toward weaker vaccine-induced immune responses in the vitamin supplemented group. Results encourage the performance of larger clinical studies before high-dose vitamin supplements are recommended for populations that are otherwise vitamin-replete.