About

Andrew Neilson is a Professor in the Food, Bioprocessing and Nutrition Sciences department at North Carolina State University, located at the Plants for Human Health Institute (PHHI) in Kannapolis, NC. His research focuses on the interactions between dietary phytochemicals, particularly flavonoids, and the gut microbiome, and how these interactions influence human health. He is specifically interested in the bioactivities of microbial metabolites produced when the gut microbiome metabolizes unabsorbed dietary components, with health areas of interest including gut health and metabolic syndrome. Dr. Neilson holds a Ph.D. in Food Science from Purdue University, obtained in 2009, and a B.S. in Food Science from Brigham Young University, earned in 2005. Prior to his current position, he spent 7.5 years as a faculty member at Virginia Tech. He is a member of professional organizations such as the American Society for Nutrition and Phi Tau Sigma. His work contributes to understanding the complex interactions between diet, microbiota, and health, advancing knowledge in food science and human nutrition.

Research topics

• Biology
• Biochemistry
• Medicine
• Internal medicine
• Endocrinology
• Food science
• Bioinformatics
• Chemistry
• Pulp and paper industry
• Environmental science
• Waste management
• Genetics
• Physiology
• Environmental chemistry
• Biotechnology
• Engineering
• Cardiology
• Pharmacology
• Immunology
• Psychology
• Materials science
• Neuroscience
• Environmental engineering
• Organic chemistry

Selected publications

• Author response for "A pilot and feasibility analysis of serum TMAO and choline in a randomized sample from the COSMOS trial"

  2025-08-27

  peer-reviewSenior author
  PublisherDOI

• A pilot and feasibility analysis of serum TMAO and choline in a randomized sample from the COSMOS trial

  Food & Function · 2025-01-01

  articleSenior authorCorresponding

  : We measured TMAO and choline from stored blood samples in this pilot study from the COSMOS trial. Although daily CE supplementation was not associated with statistically significant 1 year changes in TMAO or choline levels, our sample size was limited. Larger studies are needed to understand whether TMAO and/or choline contribute to the reduction in CVD death observed with CE supplementation.

  PublisherDOI

• Inhibition of pro-atherogenic trimethylamine production from choline by human gut bacteria is not determined by varying chlorogenic acid content in highbush blueberries

  Food & Function · 2025-01-01

  articleOpen accessSenior author

  Chlorogenic acid is an abundant phenolic in blueberries. Chlorogenic acid content was not correlated with the ability of blueberries to inhibit production of pro-atherogenic trimethylamine by gut bacteria. All blueberries tested were effective.

  PublisherOA PDFDOI

• Author response for "Inhibition of pro-atherogenic trimethylamine production from choline by human gut bacteria is not determined by varying chlorogenic acid content in highbush blueberries"

  2025-08-28

  peer-reviewSenior author
  PublisherDOI

• Author response for "A pilot and feasibility analysis of serum TMAO and choline in a randomized sample from the COSMOS trial"

  2025-09-15

  peer-reviewSenior author
  PublisherDOI

• Correction: Inhibition of pro-atherogenic trimethylamine production from choline by human gut bacteria is not determined by varying chlorogenic acid content in highbush blueberries

  Food & Function · 2025-12-08

  articleOpen accessSenior authorCorresponding

  Correction for ‘Inhibition of pro-atherogenic trimethylamine production from choline by human gut bacteria is not determined by varying chlorogenic acid content in highbush blueberries’ by Ashley M. McAmis et al. , Food Funct. , 2025, 16 , 8004–8020, https://doi.org/10/1039/D5FO02676H.

  PublisherOA PDFDOI

• Gut microbes metabolize strawberry phytochemicals and mediate their beneficial effects on vascular inflammation

  Gut Microbes · 2025-01-06 · 5 citations

  articleOpen access

  that was negatively associated with vascular inflammation and positively associated with hippuric acid. Fifth, hippuric acid was negatively associated with vascular inflammation. Our study fills in some pieces of the giant puzzle regarding the influence of gut microbes on the biological activities of phytochemicals. HFD-induced gut dysbiosis negatively impacts metabolite production and a strong association exists among gut microbes, strawberry-derived microbial metabolites, and the vascular benefits of dietary strawberries. Further, our study provides significant proof of concept to warrant future research on the use of strawberries as a nutritional strategy to prevent vascular complications.

  PublisherOA PDFDOI

• Inhibition of pro-atherogenic trimethylamine production from choline by human gut bacteria is not determined by varying chlorogenic acid content in highbush blueberries

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-06-21

  preprintSenior authorCorresponding

  Abstract Elevated blood levels of trimethylamine N-oxide (TMAO) are linked to increased risk of atherosclerosis. TMAO is produced when gut bacteria metabolize quaternary amines such as choline to trimethylamine (TMA), which is converted to TMAO in the liver. Chlorogenic acid (CGA), a phenolic abundant in blueberries, inhibits TMA production. Blueberries may be a TMA- (and TMAO)-lowering food. CGA content in blueberries varies significantly. It remains unclear whether variations in CGA levels influence the TMA-lowering activity of different cultivars. We investigated the impact of blueberry CGA content on inhibition of choline-d 9 conversion to TMA-d 9 in our upper gastrointestinal and in vitro human fecal model. Preliminary experiments indicated near-total inhibition of TMA-d 9 production when whole blueberries were tested. Blueberry pulp and sugars recapitulated this complete inhibition, whereas blueberry skins and a fiber had more moderate inhibition. We proceeded with skins (to avoid interferences from sugar-rich pulp, which would not be present in the colon in vivo ) from 20 highbush blueberry genotypes, chosen for extremes in CGA content. CGA in whole berries was 2.6-146 mg/100 g fresh weight, while CGA in skins was 13.6-975 mg/100 g fresh weight. No differences were observed in TMA-d 9 production among the 4 highest and 4 lowest CGA genotypes in kinetic curves or area under the curve (AUC) values when skin digesta were fermented with choline-d 9 . However, significant differences were observed between all genotypes compared to blank digesta, with ∼19.4.% reduction in TMA-d 9 AUCs, indicating that skins provides similar TMA-lowering benefits across genotypes. Levels of free CGA in fermenta of skin digesta were 0.05-0.3 μM, >1000-fold lower than the minimum effective dose we observed for pure CGA in vitro , suggesting that blueberry CGA content is not a crucial factor for lowering TMA. Fiber also does not account for most of the inhibitory activity of blueberry skins. Studies are needed to confirm this in vitro study and understand how blueberries inhibit TMA and potentially TMAO production in vivo .

  PublisherDOI

• Establishing reliable blood biomarkers for trimethylamine N-oxide status in rodents: Effects of oral choline challenge, dietary choline and fasting conditions

  The Journal of Nutritional Biochemistry · 2025-03-21 · 2 citations

  articleOpen accessSenior authorCorresponding

  • Dietary choline levels impact plasma trimethylamine N-oxide (TMAO) more than plasma choline. • Fasting overnight lowers plasma TMAO more than plasma choline. • Acute choline challenges may be useful for evaluating choline trimethylamine lyase inhibitors. • Nonfasting and fasting plasma sampling provides different information about TMAO status. Circulating concentrations of the gut microbial-mammalian metabolite trimethylamine N-oxide (TMAO) are linked to atherosclerosis risk. TMAO biosynthesis begins when dietary choline is converted to trimethylamine (TMA) by gut microbial TMA lyase. TMA is transported to the liver, where flavin-containing monooxygenases convert it to TMAO. While dietary modifications regulate TMAO production, the impact of different intake methods, including oral gavage, dietary supplementation, and conditions such as fasting versus nonfasting, has not been fully explored. Twelve female Sprague-Dawley rats were divided into three diet groups ( n = 4 per group): no-choline (0% choline), low-choline (0.08% choline), and high-choline (1% choline). Choline and TMAO fasting and nonfasting blood concentrations, and their kinetics following an acute choline challenge, were assessed before and after a 2-week dietary intervention with the distinct choline dietary levels. Fasting choline was under tight control, with little effect of dietary choline. Nonfasting choline was more variable, with high dietary choline reflected in higher blood choline. Greater levels of dietary choline were reflected in significantly greater levels of TMAO, particularly for nonfasting levels. Kinetic profiling demonstrated additional information regarding the appearance and clearance of these compounds from blood. These results suggest that acute oral choline gavage is likely most suitable for studies targeting acute (direct) inhibitors, whereas a choline-rich diet with assessment of fasting and nonfasting blood levels is more suitable for studying alterations to TMAO production capacity. Future research should examine the impact on atherosclerosis biomarkers and microbiome diversity to deepen the understanding of TMAO regulation and its cardiovascular implications. This study examined fasting and nonfasting blood levels of choline and trimethylamine N-oxide (TMAO) following a 2-week dietary intervention with no-choline (0%), low-choline (0.08%), and high-choline (1%) diets. Acute choline challenge via oral gavage and dietary supplementation revealed significant differences in TMAO metabolism, with higher nonfasting TMAO levels in the high-choline group. These findings provide insights into optimizing experimental conditions for studying TMAO-lowering strategies.

  PublisherDOI

• 469 Identification of gut barrier protective fruits and vegetables for Latin American infants

  Journal of Clinical and Translational Science · 2025-03-25

  articleOpen access

  Objectives/Goals: Early childhood obesity is a major concern for Latin American children in the U.S., with gut barrier dysfunction as a key risk factor. Diet plays a role in gut development, but few studies have focused on Latin American infants. Our objective is to identify culturally relevant introductory foods that promote in vitro gut barrier development and function. Methods/Study Population: Pooled human milk (2.5 mL) from 6-month postpartum Hispanic mothers was combined with fruit and vegetable baby food products (2.5 g) and subjected to a 3-phase in vitro digestion system that simulates oral, gastric, and intestinal digestion. Digesta products were then anaerobically fermented for 24-hours using human stool inoculum, centrifuged, and filter sterilized. Intestinal epithelial cells (Caco-2, ATCC) were grown to confluence on 0.4 μm polystyrene transwell inserts using a DMEM + 10% FBS medium and allowed to differentiate for 21-days. Highly differentiated monolayers were treated with a 1:4 dilution of fermenta with medium in triplicate. The cell experiment was conducted twice. Cell layer integrity was measured using transepithelial electrical resistance (TEER) 24- and 48-hours after treatment. Results/Anticipated Results: Dietary intake data from the What We Eat in America database indicated that the top 3 fruit and vegetable exposures for infants with Mexican or Hispanic ethnicity were banana, apple, and carrot. Commercial baby food purees of these fruits and vegetables, in addition to baby foods with blueberry and spinach (Natural for Baby, Gerber Products Company) were acquired for digestion and fermentation experiments. Caco-2 cell experiments with these foods are ongoing. We expect Caco-2 monolayer incubated with fermenta from human milk and fruit or vegetables will have greater TEER values due to increased integrity of the cell layer as compared to those with breast milk alone. We also expect that exposure to fruit and vegetable fermenta will increase gene expression of tight junctions compared to exposure to media and human milk. Discussion/Significance of Impact: Using an in vitro digestion and fermentation system coupled with cell culture studies, we are identifying cellular mechanisms that link individual fruits and vegetables to gut barrier function. This will support translational work focused on mitigating obesity development in vulnerable populations.

  PublisherOA PDFDOI

Frequent coauthors

• Mário G. Ferruzzi

  Arkansas Children's Nutrition Center

  62 shared

• Amanda C. Stewart

  Virginia Tech

  38 shared

• Lisard Iglesias‐Carres

  Universidad Rovira i Virgili

  35 shared

• Sean F. O’Keefe

  Virginia Tech

  34 shared

• Laura E. Griffin

  31 shared

• Kathryn Racine

  North Carolina State University

  26 shared

• Kevin P. Davy

  Virginia Tech

  26 shared

• Jeffery S. Tessem

  Provo College

  25 shared

Education

• Ph.D., Food, Bioprocessing and Nutrition Sciences

  North Carolina State University

  2013

• M.S., Food, Bioprocessing and Nutrition Sciences

  North Carolina State University

  2009

• B.S., Food, Bioprocessing and Nutrition Sciences

  North Carolina State University

  2007