Matthew J Landry

Dr. Matthew J Landry

Stanford University
orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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31 May 2022 in The American Journal of Clinical Nutrition
Verified
Journal Article
Open access
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CGChristopher Gardner
Christopher Gardner
Matthew J LandryMatthew J Landry
Matthew J Landry
DPDalia Perelman
Dalia Perelman
CPChristina Petlura
Christina Petlura
LDLindsay R Durand
Lindsay R Durand
SKSun H Kim
Sun H Kim
Consensus has not been reached on what constitutes an optimal diet in individuals with prediabetes and type 2 diabetes mellitus (T2DM), especially between low-carbohydrate options. We compared 2 low-carbohydrate diets with 3 key similarities (incorporating nonstarchy vegetables and avoiding added sugars and refined grains) and 3 key differences (incorporating compared with avoiding legumes, fruits, and whole, intact grains) for their effects on glucose control and cardiometabolic risk factors in individuals with prediabetes and T2DM. Keto-Med was a randomized, crossover, interventional trial. Forty participants aged ≥18 years with prediabetes or T2DM followed the well-formulated ketogenic diet (WFKD) and the Mediterranean-plus diet (Med-Plus) for 12 weeks each, in random order. The diets shared the 3 key similarities noted above. The Med-Plus incorporated legumes, fruits, and whole, intact grains, while the WFKD avoided them. The primary outcome was the percentage change in glycated hemoglobin (HbA1c) after 12 weeks on each diet. Secondary and exploratory outcomes included percentage changes in body weight, fasting insulin, glucose, and blood lipids; average glucose from continuous glucose monitor (CGM), and nutrient intake. The primary analysis was of 33 participants with complete data. The HbA1c values did not differ between diets at 12 weeks. Triglycerides decreased more for the WFKD [percentage changes, −16% (SEM, 4%) compared with −5% (SEM, 6%) for the Med-Plus; P = 0.02] and LDL cholesterol was higher for the WFKD [percentage changes, +10% (SEM, 4%) compared with −5% (SEM, 5%) for the Med-Plus; P = 0.01]. Weight decreased 8% (SEM, 1%) compared with 7% (SEM, 1%) and HDL cholesterol increased 11% (SEM, 2%) compared with 7% (SEM, 3%) for the WFKD compared with the Med-Plus, respectively; however, there was a significant interaction of diet × order for both. Participants had lower intakes of fiber and 3 nutrients on the WFKD compared with the Med-Plus. Twelve-week follow-up data suggest the Med-Plus is more sustainable. HbA1c values were not different between diet phases after 12 weeks, but improved from baseline on both diets, likely due to several shared dietary aspects. The WFKD led to a greater decrease in triglycerides, but also had potential untoward risks from elevated LDL cholesterol and lower nutrient intakes from avoiding legumes, fruits, and whole, intact grains, as well as being less sustainable. This trial was registered at clinicaltrials.gov as NCT03810378.

22 October 2021 in Current Obesity Reports
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Journal Article
Open access
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Anthony CrimarcoAnthony Crimarco
Anthony Crimarco
Matthew J LandryMatthew J Landry
Matthew J Landry
CGChristopher Gardner
Christopher Gardner
Purpose of Review: The purpose of this review is to provide an update on the available data regarding the associations of Ultra-processed food (UPF) consumption with food intake and possible underlying mechanisms relating UPF consumption to weight gain and co-morbidities. Recent Findings: In primarily observational studies, UPF consumption is consistently associated with an increased risk for weight gain among adults and children and increased risk for adiposity-related co-morbidities in adults. In a single mechanistic study, consumption of UPFs led to increased energy intake and weight gain relative to whole foods. Summary: UPFs tend to be more energy-dense than nutrient-dense, and UPF consumption is associated with increased adiposity and co-morbidity risk. These data suggest that recommendations to limit UPF consumption may be beneficial to health — though further mechanistic studies are needed.

23 January 2021 in International Journal of Behavioral Nutrition and Physical Activity
Verified
Journal Article
Open access
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JDJaimie Davis
Jaimie Davis
APAdriana Pérez
Adriana Pérez
FAFiona M. Asigbee
Fiona M. Asigbee
Matthew J LandryMatthew J Landry
Matthew J Landry
SVSarvenaz Vandyousefi
Sarvenaz Vandyousefi
ABAlexandra E. Van Den Berg
Alexandra E. Van Den Berg
Background: Although school garden programs have been shown to improve dietary behaviors, there has not been a cluster-randomized controlled trial (RCT) conducted to examine the effects of school garden programs on obesity or other health outcomes. The goal of this study was to evaluate the effects of a one-year school-based gardening, nutrition, and cooking intervention (called Texas Sprouts) on dietary intake, obesity outcomes, and blood pressure in elementary school children.Methods: This study was a school-based cluster RCT with 16 elementary schools that were randomly assigned to either the Texas Sprouts intervention (n = 8 schools) or to control (delayed intervention, n = 8 schools). The intervention was one school year long (9 months) and consisted of: a) Garden Leadership Committee formation; b) a 0.25-acre outdoor teaching garden; c) 18 student gardening, nutrition, and cooking lessons taught by trained educators throughout the school-year; and d) nine monthly parent lessons. The delayed intervention was implemented the following academic year and received the same protocol as the intervention arm. Child outcomes measured were anthropometrics (i.e., BMI parameters, waist circumference, and body fat percentage via bioelectrical impedance), blood pressure, and dietary intake (i.e., vegetable, fruit, and sugar sweetened beverages) via survey. Data were analyzed with complete cases and with imputations at random. Generalized weighted linear mixed models were used to test the intervention effects and to account for clustering effect of sampling by school.Results: A total of 3135 children were enrolled in the study (interventionn = 1412, 45%). Average age was 9.2 years, 64% Hispanic, 47% male, and 69% eligible for free and reduced lunch. The intervention compared to control resulted in increased vegetable intake (+ 0.48 vs. + 0.04 frequency/day,p = 0.02). There were no effects of the intervention compared to control on fruit intake, sugar sweetened beverages, any of the obesity measures or blood pressure.Conclusion: While this school-based gardening, nutrition, and cooking program did not reduce obesity markers or blood pressure, it did result in increased vegetable intake. It is possible that a longer and more sustained effect of increased vegetable intake is needed to lead to reductions in obesity markers and blood pressure.Clinical trials number: NCT02668744.

12 July 2019 in Nutrients
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Journal Article
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Matthew J LandryMatthew J Landry
Matthew J Landry
Alexandra E. van den BergAlexandra E. van den Berg
Alexandra E. van den Berg
FAFiona M. Asigbee
Fiona M. Asigbee
SVSarvenaz Vandyousefi
Sarvenaz Vandyousefi
RGReem Ghaddar
Reem Ghaddar
JDJaimie Davis
Jaimie Davis
Food insecurity (FI) is adversely associated with physical and mental wellbeing in children. The mechanism underlying this association is assumed to be dietary intake; however, evidence has been mixed. This study examined the relationship between self-reported FI and dietary quality among low-income children. Cross-sectional data were used from TX Sprouts, a school-based cooking, gardening, and nutrition intervention. A sample of 598 children completed two 24-h dietary recalls and a questionnaire including an adapted version of the 5-item Child Food Security Assessment (CFSA). Food security was categorized as food secure or FI based on summed CFSA scores. Dietary quality was assessed using the Health Eating Index-2015 (HEI-2015). Mixed effects linear regression models examined associations between FI and dietary quality. Children were 64% Hispanic, 55% female, and were 9.2 years old on average. Adjusting for sociodemographic characteristics, BMI percentile, and energy intake, FI was associated with lower HEI-2015 total scores (β = −3.17; 95% CI = −5.28, −1.06; p = 0.003). Compared to food secure children, FI children had lower greens and beans (2.3 vs. 1.9, p = 0.016), seafood and plant protein (2.0 vs. 1.6, p = 0.006), and added sugar (7.4 vs. 8.0, p = 0.002) component scores. Interventions targeting low-income and FI children should investigate ways to improve dietary quality.

7 February 2025 in Journal of the Academy of Nutrition and Dietetics
Verified
Journal Article
Closed access
SRSudha Raj
Sudha Raj
NGNanci Susan Guest
Nanci Susan Guest
Matthew J LandryMatthew J Landry
Matthew J Landry
AMA. Reed Mangels
A. Reed Mangels
RPRoman Pawlak
Roman Pawlak
MRMary Rozga
Mary Rozga

29 July 2021 in Current Developments in Nutrition
Verified
Journal Article
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MRMarcela D Radtke
Marcela D Radtke
MPMykaela Poe
Mykaela Poe
JSJodi Stookey
Jodi Stookey
SPStephanie Jilcott Pitts
Stephanie Jilcott Pitts
NMNancy E Moran
Nancy E Moran
Rachel ScherrRachel Scherr
Rachel Scherr
Carotenoids are a class of phytochemical compounds found in a variety of fruits and vegetables (F/V) and, therefore, are commonly used as a biomarker for F/V intake. The Veggie Meter® is a noninvasive research-grade instrument that detects and quantifies carotenoids in the skin. To determine current practices and examine variability among users, a survey was administered to researchers using the device (n = 19, response rate = 35.8%) and variation in anatomical site preparation, calibration, number of measurements, measurement site, and documentation was observed. A protocol was developed in partnership with Veggie Meter® users to outline the preparation, calibration, and data collection procedures for using this device for research purposes. Although many protocol conditions will benefit from additional validation, this standardized protocol supports the development of a universal data repository to establish usual observed ranges, with the ultimate goal of examining associations between skin carotenoid scores and diet-related health outcomes.