Michael Herschel Greger (born October 25, 1972) is an American physician, author, and speaker onpublic health issues best known for his advocacy of awhole-food,plant-based diet, and his opposition to animal-derived food products.
Early life and education
Michael Greger was born on October 25, 1972,[1][2][3] inMiami,Florida,United States.[4][5] Greger has said that he was inspired to pursue a career in medicine at the age of nine after witnessing his grandmother's health improvement[6][7] that she attributed to following dietary and lifestyle changes prescribed by American nutritionistNathan Pritikin.[8][9] He later graduated from theCornell University School of Agriculture in 1995,[10][11][12] where as a junior he wrote informally about the dangers ofbovine spongiform encephalopathy on a website he published in 1994.[13][14] In the same year, he was hired to work on mad cow issues forFarm Sanctuary, near Cornell, and became a vegan after touring a stockyard as part of his work with Farm Sanctuary.[10]
In 1998, Greger appeared as an expert witness testifying about bovine spongiform encephalopathy when cattle producers unsuccessfully suedOprah Winfrey forlibel over statements she had made about the safety of meat in 1996.[10][15][16] He later enrolled atTufts University School of Medicine, originally for its MD/PhD program, but then withdrew from the dual-degree program to pursue only the medical degree.[17] He received his MD in 1999 as ageneral practitioner specializing inclinical nutrition.[6][10][18]
In 2001, Greger joined theOrganic Consumers Association to work on mad cow issues, on which he spoke widely as cases of the disease appeared in the US and Canada.[10][19][20][21] Previously in 1994, in aCornell University animal rights publication, Greger highlighted the results of a survey in Britain that appeared to support the view of a microbiologist at theUniversity of Leeds that mad cow disease was "much more serious thanAIDS".[22] A decade later, in early 2004, theDaily Bruin, the student newspaper of theUniversity of California, Los Angeles, reported that Greger had called mad cow disease the "plague of the 21st century".[23] However, Greger later denied ever making such a statement, clarifying that he had merely posed it as a question during a speech.[24] That same year, Greger cited a study and said that "thousands of Americans may already be dying because of Mad Cow disease every year".[25][26]
In 2004, he launched a website and published a book critical of theAtkins Diet and otherlow-carbohydrate diets.[10] That same year, the American College of Lifestyle Medicine was founded,[27] and Greger was a founding member,[6][10][28] and fellow.[18]
Greger founded the websiteNutritionFacts.org,[33][34] with funding from the Jesse & Julie Rasch Foundation.[35][36] It was founded in August 2011 to provide information on nutrition and health.[37] Jesse & Julie Rasch Foundation provided the initial seed funding.[38] Greger, then known forpublic-health lectures and his work with theHumane Society of the United States, aimed to "cut through the hype" by summarizing findings frompeer-reviewed studies in an accessible format. From its inception, the site released a new video every weekday, drawing on Greger'sLatest in Clinical Nutrition lecture series, to make complex research digestible for the general public.[37]
NutritionFacts.org follows a nonprofit public-service model. It carries no advertisements and sells no products; operating costs are covered by individual donations and philanthropic grants. Its core service is its video library: referenced videos, most narrated by Greger, which summarizes recent nutrition studies. Each video is accompanied by a transcript andcitation list, which helps readers to trace the original research.[39][40]
In 2017, Greger received the ACLM Trailblazer Award inlifestyle medicine, with NutritionFacts.org cited as a model of freely available, evidence-based education.[41]
In 2025, itspodcastNutrition Facts with Dr. Greger[42] was voted "Best Podcast" in theVegNews Veggie Awards.[43]
Greger's third book,Bird Flu: A Virus of Our Own Hatching, received a favorable review which said it was "interesting and informative to both scientists and lay persons".[51] Public health expertDavid Sencer was critical of the book, writing that it "focuses heavily on doomsday scenarios and offers little in terms of practical advice to the public" and that "a professional audience would quickly put [the book] aside for more factually correct sources of information".[52]
In 2024, Morgan Pfiffner ofRed Pen Reviews gave his sixth book,How Not to Diet a score of 50% for its scientific accuracy and a score of 75% for its healthfulness. Pfiffner commented that "While much of the book is well supported by research, there are a significant number of fairly questionable claims, leading to a handful of dietary recommendations that seem unnecessary, too restrictive, or potentially counterproductive". He also argues that Greger's claim that a whole food plant-based diet can reverse heart disease is questionable. According to Pfiffner this has not been demonstrated as the randomized controlled trial that he cited fromDean Ornish did not show regression of atherosclerotic plaque.[53]
Harriet Hall argues that, while it is well-accepted that it is more healthy to eat a plant-based diet than a typical Western diet, Greger often overstates the known benefits of such a diet as well as the harm caused by eating animal products (for example, in a talk, he claimed that a single meal rich in animal products can "cripple" one's arteries), and he sometimes does not discuss evidence that contradicts his strong claims.[54]Joseph A. Schwarcz ofMcGill University argues that although Greger takes his information from respected science journals and produces impressive videos, he has a vegan agenda and cherry picks his data. He adds, "Of course that doesn't mean the cherries he picks are rotten; they're fine."[55]
Publications
Greger advocates for a general move away from aWestern pattern diet to awhole-food,plant-based diet.[36][56][57] He has been critical of theUSDA, stating that "a conflict of interest right in their mission statement" protects the economic interests of food producers in lieu of clear dietary guidelines.[58]
Lower LDL Cholesterol Naturally with Food: Simple Ways to Add Proven LDL Reducers to Your Everyday Routine. Takoma Park, Maryland: NutritionFacts.org. 2025. ISBN 979-8991660556. (with Kristine Dennis)
Media from Commons
Quotations from Wikiquote
Data from Wikidata
