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Clinical Research

Physicians Committee Publications

The Physicians Committee designs and conducts clinical research studies on nutrition and health. Dietary interventions have appeared promising in investigations carried out by numerous research teams, including our own. We have conducted studies that examine the effects of diet on weight, cardiovascular risk, cancer prevention and survival, and other health issues. The Physicians Committee's research aims to develop and test practical interventions that can be used by doctors and patients. The Physicians Committee also conducts detailed reviews of the scientific literature, including meta-analyses.

Diabetic Neuropathy

List: Bunner AE, Wells CL, Gonzales J, Agarwal U, Bayat E, Barnard ND. A dietary intervention for chronic diabetic neuropathy pain: a randomized controlled pilot studyNutrition & Diabetes. 2015;5:e158.

Diabetes Studies

GEICO Studies

Mediterranean Diet Versus Low-Fat Vegan Diet

Barnard ND, Alwarith J, Rembert E, et al. A Mediterranean diet and low-fat vegan diet to improve body weight and cardiometabolic risk factors: a randomized, cross-over trial. J Am Nutr Assoc. 2022;41(2):127-139. doi:10.1080/07315724.2020.1869625

Menopause Studies

  • Kahleova H, Znayenko-Miller T, Uribarri J, et al. Dietary advanced glycation end-products and postmenopausal hot flashes: a post-hoc analysis of a 12-week randomized clinical trial. Maturitas. 2023;172:32-38. doi:10.1016/j.maturitas.2023.03.008
  • Barnard ND, Kahleova H, Holtz DN, et al. A dietary intervention for vasomotor symptoms of menopause: a randomized, controlled trial. Menopause. 2023;30(1):80-87. doi:10.1097/GME.0000000000002080
  • Barnard ND, Kahleova H, Holtz DN, et al. The Women's Study for the Alleviation of Vasomotor Symptoms (WAVS): a randomized, controlled trial of a plant-based diet and whole soybeans for postmenopausal women. Menopause. 2021;28(10):1150-1156.

Rheumatoid Arthritis

Barnard ND, Levin S, Crosby L, Flores R, Holubkov R, Kahleova H. A randomized, crossover trial of a nutritional intervention for rheumatoid arthritis. Am J Lifestyle Med. Published online April 3, 2022. doi:10.1177/15598276221081819

Additional Research, Reviews, and Editorials

Reynolds A, The Diabetes and Nutrition Study Group (DNSG) of the European Association for the Study of Diabetes (EASD). Evidence-based European recommendations for the dietary management of diabetes. Diabetologia. Published online April 17, 2023. doi:10.1007/s00125-023-05894-8

Cullimore JP, Herby AR, Paul-Quinn JL, Levin S, Stancic S. The nutritional content of animal and plant milks and their health implications. International Journal of Disease Reversal and Prevention. 2023;5(1):13. doi:10.22230/ijdrp.2023v5n1a363

Herby A, Cullimore J, Paul-Quinn J, Crosby L. Dairy intake and incidence of common cancers in prospective studies: a narrative review. International Journal of Disease Reversal and Prevention. 2023;5(1):14. doi:10.22230/ijdrp.2023v5n1a365

Barnard ND, Holtz DN, Schmidt N, et al. Nutrition in the prevention and treatment of endometriosis: a review. Front Nutr. 2023;10:1089891. doi:10.3389/fnut.2023.1089891

Kahleova H, Znayenko-Miller T, Uribarri J, Holubkov R, Barnard ND. Dietary advanced glycation products and their associations with insulin sensitivity and body weight: a 16-week randomized clinical trial. Obesity Science and Practice. Published online October 17, 2022. doi:10.1002/osp4.646

Crosby L, Rembert E, Levin S, et al. Changes in food and nutrient intake and diet quality on a low-fat vegan diet are associated with changes in body weight, body composition, and insulin sensitivity in overweight adults: a randomized clinical trial. J Acad Nutr Diet. 2022;122(10):1922-1939.e0. doi:10.1016/j.jand.2022.04.008

Stancic S, Cullimore J, Barnard N. Six applications of plant based diets for health promotion. Am J Lifestyle Med. 2022;16(4):434-438. doi:10.1177/15598276221104023

Kahleova H, Barnard ND. The role of nutrition in COVID-19: taking a lesson from the 1918 H1N1 pandemic. Am J Lifestyle Med. 2022;17(1):161-163. doi:10.1177/15598276221097621

Kahleova H, Barnard ND. Can a plant-based diet help mitigate Covid-19? Eur J Clin Nutr. 2022;76(7):911-912. doi:10.1038/s41430-022-01082-w

Kahleova H, Berrien-Lopez R, Holtz D, et al. Nutrition for hospital workers during a crisis: effect of a plant-based dietary intervention on cardiometabolic outcomes and quality of life in healthcare employees during the COVID-19 pandemic. Am J Lifestyle Med. 2021;16(3):399-407. doi:10.1177/15598276211050339

Stancic S, Cullimore J, Barnard ND. Shoring up vaccine efficacy. Am J Med. 2022;135(3):271-272. doi:10.1016/j.amjmed.2021.09.002

Crosby L, Davis B, Joshi S, et al. Ketogenic diets and chronic disease: weighing the benefits against the risks. Front Nutr. 2021;8:702802. doi:10.3389/fnut.2021.702802


Jardine MA, Kahleova H, Levin SM, Ali Z, Trapp CB, Barnard ND. Perspective: plant-based eating pattern for type 2 diabetes prevention and treatment: efficacy, mechanisms, and practical considerations. Adv Nutr. 2021;12(6):2045-2055. doi:10.1093/advances/nmab063

Barnard ND, Rembert E, Freeman A, Bradshaw M, Holubkov R, Kahleova H. Blood type is not associated with changes in cardiometabolic outcomes in response to a plant-based dietary intervention. J Acad Nutr Diet. 2021;121(6):1080-1086. doi:10.1016/j.jand.2020.08.079

Kahleova H, Levin S, Barnard ND. Plant-based diets for healthy aging. J Am Coll Nutr. 2021;40(5):478-479. doi:10.1080/07315724.2020.1790442

Kahleova H, Petersen KF, Shulman GI, et al. Effect of a low-fat vegan diet on body weight, insulin sensitivity, postprandial metabolism, and intramyocellular and hepatocellular lipid levels in overweight adults: a randomized clinical trial. JAMA Netw Open. 2020;3(11):e2025454. doi:10.1001/jamanetworkopen.2020.25454

Kahleova H, Carlsen B, Berrien Lopez R, Barnard ND. Anti-diabetic, haematinic and anti-cholesterolmic effects of wheat (Triticum aestivum Linn.) Plant-based diets for type 1 diabetes. J Diab Metab. 2020;11:847. doi:10.35248/2155-6156.20.11.847

Barnard ND, Long MB, Ferguson JM, Flores R, Kahleova H. Industry funding and cholesterol research: a systematic review. Am J Lifestyle Med. 2019;15(2):165-172. doi:10.1177/1559827619892198

Viguiliouk E, Glenn AJ, Nishi SK, et al. Associations between dietary pulses alone or with other legumes and cardiometabolic disease outcomes: an umbrella review and updated systematic review and meta-analysis of prospective cohort studies. Adv Nutr. 2019;10(Suppl_4):S308-S319. doi:10.1093/advances/nmz113

Flores R, Eckart J, Nash K, Kwitowski E. Implementation of vegan entrees in a Washington, D.C. elementary school. Journal of Child Nutrition and Management. 2019;43(2).

Alwarith J, Kahleova H, Rembert E, et al. Nutrition interventions in rheumatoid arthritis: the potential use of plant-based diets. A review. Front Nutr. 2019;6:141. doi:10.3389/fnut.2019.00141

Sandefur K, Kahleova H, Desmond AN, Elfrink E, Barnard ND. Crohn's disease remission with a plant-based diet: a case report. Nutrients. 2019;11(6):1385. doi:10.3390/nu11061385

Kahleova H, Tura A, Klementova M, et al. A plant-based meal stimulates incretin and insulin secretion more than an energy- and macronutrient-matched standard meal in type 2 diabetes: a randomized crossover study. Nutrients. 2019;11(3):486. doi:10.3390/nu11030486

Klementova M, Thieme L, Haluzik M, et al. A plant-based meal increases gastrointestinal hormones and satiety more than an energy- and macronutrient-matched processed-meat meal in T2D, obese, and healthy men: a three-group randomized crossover study. Nutrients. 2019;11(1):157. doi:10.3390/nu11010157

Viguiliouk E, Kendall CW, Kahleová H, et al. Effect of vegetarian dietary patterns on cardiometabolic risk factors in diabetes: a systematic review and meta-analysis of randomized controlled trials. Clin Nutr. 2019;38(3):1133-1145. doi:10.1016/j.clnu.2018.05.032

Chiavaroli L, Nishi SK, Khan TA, et al. Portfolio dietary pattern and cardiovascular disease: a systematic review and meta-analysis of controlled trials. Prog Cardiovasc Dis. 2018;61(1):43-53. doi:10.1016/j.pcad.2018.05.004

Kahleova H, Levin S, Barnard ND. Vegetarian dietary patterns and cardiovascular disease. Prog Cardiovasc Dis. 2018;61(1):54-61. doi:10.1016/j.pcad.2018.05.002

Barnard ND, Levin SM, Gloede L, Flores R. Turning the waiting room into a classroom: weekly classes using a vegan or a portion-controlled eating plan improve diabetes control in a randomized translational study. J Acad Nutr Diet. 2018;118(6):1072-1079. doi:10.1016/j.jand.2017.11.017

Kahleova H, Tura A, Hill M, Holubkov R, Barnard ND. A plant-based dietary intervention improves beta-cell function and insulin resistance in overweight adults: a 16-week randomized clinical trial. Nutrients. 2018;10(2):189. doi:10.3390/nu10020189

Kahleova H, Klementova M, Herynek V, et al. The effect of a vegetarian vs conventional hypocaloric diabetic diet on thigh adipose tissue distribution in subjects with type 2 diabetes: a randomized studyJ Am Coll Nutr. 2018;36:364-369.

Barnard ND, Willett WC, Ding EL. The misuse of meta-analysis in nutrition researchJAMA. 2017;318:1435-1436.

Yokoyama Y, Levin SM, Barnard ND. Association between plant-based diets and plasma lipids: a systematic review and meta-analysisNutr Rev. 2017;75:683-698.

Kahleova H, Levin S, Barnard N. Cardio-metabolic benefits of plant-based dietsNutrients. 2017; 9. pii: E848.

Kahleova H, Lloren JI, Mashchak A, Hill M, Fraser GE. Meal frequency and timing are associated with changes in body mass index in Adventist Health Study 2J Nutr. 2017;147:1722-1728.

Freeman AM, Morris PB, Barnard N, et al. Trending cardiovascular nutrition controversiesJ Am Coll Cardiol. 2017;69:1172-1187.

Barnard ND, Levin SM, Yokoyama Y. A systematic review and meta-analysis of changes in body weight in clinical trials of vegetarian dietsJ Acad Nutr Diet. 2015;115:954-969.

Yokoyama Y, Barnard ND, Levin SM, Watanabe M. Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysisCardiovasc Diagn Ther. 2014;4:373-82.

Bunner AE, Agarwal U, Gonzales JF, Valente F, Barnard ND. Nutrition intervention for migraine: a randomized crossover trialJ Headache Pain. 2014 Oct 23;15:69

Barnard ND, Bunner AE, Agarwal U. Saturated and trans fats and dementia: a systematic reviewNeurobiol Aging. 2014;35(Suppl 2):S65-73.

Barnard ND, Bush AI, Ceccarelli A, et al. Dietary and lifestyle guidelines for the prevention of Alzheimer's diseaseNeurobiol Aging. 2014;35(Suppl 2):S74-78.

Yokoyama Y, Nishimura K, Barnard ND, et al. Vegetarian diets and blood pressure: a meta-analysis. JAMA Intern Med. 2014;174:577-587.

Gonzales JF, Barnard ND, Jenkins DJ, Lanou AJ, Davis B, Saxe G, Levin S. Applying the precautionary principle to nutrition and cancerJ Am Coll Nutr. 2014;33:239-246.

Barnard ND. The physician's role in nutrition-related disorders: from bystander to leaderVirtual Mentor. 2013;15:367-372.

Agarwal U. Rethinking red meat as a prevention strategy for iron deficiencyInfant, Child, & Adolescent Nutrition. 2013;5:231-235.

Trapp CB, Barnard ND. Usefulness of vegetarian and vegan diets for treating type 2 diabetesCurr Diab Rep. 2010;10:152-158.

Trapp C, Barnard N, Katcher H. A plant-based diet for type 2 diabetes: scientific support and practical strategiesDiabetes Educ. 2010;36:33-48.

Berkow SE, Barnard N, Eckart J, Katcher H. Four therapeutic diets: adherence and acceptability. Can J Diet Pract Res. 2010;71:199-204.

Barnard ND. Trends in food availability, 1909-2007Am J Clin Nutr. 2010;91:1530S-1536S.

Lanou AJ. Should dairy be recommended as part of a healthy vegetarian diet? Am J Clin Nutr. 2009;89:1638S-1642S.

Barnard ND, Levin S. Vegetarian diets and disordered eatingJ Am Diet Assoc. 2009;109:1523; author reply 1523-1524.

Spencer EH, Ferdowsian HR, Barnard ND. Diet and acne: a review of the evidenceInt J Dermatol. 2009;48:339-347.

Ferdowsian HR, Barnard ND. Effects of plant-based diets on plasma lipidsAm J Cardiol. 2009;104:947-956.

Barnard ND, Katcher HI, Jenkins DJ, Cohen J, Turner-McGrievy G. Vegetarian and vegan diets in type 2 diabetes managementNutr Rev. 2009;67:255-263.

Lanou AJ, Barnard ND. Dairy and weight loss hypothesis: an evaluation of the clinical trialsNutr Rev. 2008;66:272-279.

Turner-McGrievy GM, Barnard ND, Scialli AR. A two-year randomized weight loss trial comparing a vegan diet to a more moderate low-fat dietObesity (Silver Spring). 2007;15:2276-2281.

Barnard ND, Scialli AR, Turner-McGrievy G, Lanou AJ, Glass J. The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivityAm J Med. 2005;118:991-997. 

Turner-McGrievy GM, Barnard ND, Scialli AR, Lanou AJ. Effects of a low-fat vegan diet and a Step II diet on macro- and micronutrient intakes in overweight postmenopausal womenNutrition. 2004;20:738-746. 

Barnard ND, Scialli AR, Hurlock D, Bertron P. Diet and sex-hormone binding globulin, dysmenorrhea, and premenstrual symptomsObstet Gynecol. 2000;95:245-250.

Barnard ND, Scialli AR, Bertron P, Hurlock D, Edmonds K, Talev L. Effectiveness of a low-fat vegetarian diet in altering serum lipids in healthy premenopausal womenAm J Cardiol. 2000;85:969-972.