How Not to Die by Dr. Michael Greger: An Evidence-Based Review

Dr. Michael Greger’s international bestseller “How Not to Die” has inspired millions to reconsider their dietary choices. Drawing from his personal experience watching his grandmother recover from heart disease through dietary intervention, Greger presents a comprehensive 562-page guide advocating whole-food, plant-based nutrition as the key to preventing and reversing chronic diseases.

As the founder of NutritionFacts.org and a prominent voice in plant-based nutrition, Dr. Greger has built a reputation for translating complex nutritional science into actionable advice. However, like any work advocating a specific dietary approach, “How Not to Die” deserves careful scrutiny of both its merits and its methodological limitations.

The Core Message of How Not to Die

At its heart, “How Not to Die” argues that the leading causes of death in developed nations—heart disease, cancer, diabetes, and other chronic conditions—are largely preventable through dietary choices. Greger emphasizes unprocessed plant foods as protective and positions animal products and processed foods as primary contributors to disease.

Unlike stricter vegan literature, Greger acknowledges the flexibility inherent in “plant-based” eating, recognizing that occasional indulgences are part of being human. His approach focuses on whole grains, legumes, fruits, vegetables, nuts, and seeds as the foundation of optimal health.

The book is divided into two main sections: the first examines the fifteen leading causes of death and how dietary changes may prevent them, while the second outlines his “Daily Dozen”—twelve food categories he recommends consuming daily.

Strengths of the Book

Extensive Research and References

One undeniable strength of “How Not to Die” is its exhaustive citation list. Greger draws from thousands of peer-reviewed studies, making the book a valuable resource for readers seeking evidence-based nutritional information. The sheer scope of research covered provides readers with entry points for deeper investigation into topics of personal interest.

Challenging the Medical-Industrial Complex

Greger effectively highlights legitimate concerns about profit-driven healthcare systems and the pharmaceutical industry’s influence on medical practice. His emphasis on food as medicine—a concept often overlooked in conventional medical education—resonates with growing public awareness about preventive health approaches.

Vindication of Misunderstood Foods

The book successfully rehabilitates several foods that have been unfairly maligned. Greger presents compelling evidence that:

• Whole fruits, despite containing natural sugars, don’t negatively impact blood sugar control in the way processed sugars do
• Legumes offer significant benefits for weight management, insulin sensitivity, and cholesterol levels
• Phytates in plant foods, often criticized as “antinutrients,” actually possess protective properties against cancer

These sections demonstrate Greger’s ability to synthesize research effectively when presenting balanced evidence.

Critical Limitations and Concerns

Selective Citation of Evidence

Perhaps the most significant weakness in “How Not to Die” is the frequent practice of cherry-picking studies that support predetermined conclusions while ignoring contradictory evidence. This selective approach undermines the book’s scientific credibility.

For example, when discussing kidney stones and oxalates, Greger cites a study on total vegetable intake to claim high-oxalate vegetables aren’t problematic. However, the referenced study doesn’t actually examine high-oxalate vegetables specifically, and the researchers themselves suggested that high-oxalate foods might have offset some protective benefits observed.

Similarly, when presenting evidence that animal protein increases kidney stone risk, Greger states that meat eaters had higher risk and that more meat consumption meant higher risk. The actual study showed that while heavy meat eaters had the highest risk, people consuming small amounts of meat fared better than vegetarians.

Inconsistent Definition of “Plant-Based”

Greger sometimes redefines what constitutes “plant-based” to claim victories for his dietary approach. He credits the Rice Diet—composed primarily of white rice, refined sugar, and fruit juice—with reversing diabetic complications and kidney failure, despite this highly processed regimen bearing little resemblance to the whole-food approach he otherwise advocates.

Oversimplification of Complex Research

The Omega-3 Controversy

When discussing cardiovascular disease, Greger challenges the protective effects of omega-3 fatty acids from fish by citing a heavily criticized meta-analysis from 2012. He overlooks that:

• The average omega-3 intake in included studies was only half the amount recommended for heart disease prevention
• The analysis used an unnecessarily stringent cutoff for statistical significance
• Many participants were already taking statin medications, which may mask omega-3 benefits
• More recent, methodologically sound reviews support omega-3 consumption for cardiovascular protection

Asthma and Dietary Patterns

In the asthma section, Greger presents studies showing plant foods reduce respiratory symptoms but omits findings from the same studies indicating that seafood consumption was inversely associated with asthma symptoms, often more strongly than plant foods.

Multiple studies suggest omega-3 fatty acids in fish reduce inflammatory cytokine synthesis and support respiratory health—information absent from Greger’s analysis. Additionally, one study he cites showed milk consumption was protective against asthma, contradicting his narrative about animal foods.

Dementia and Alzheimer’s Disease

Greger discusses international studies showing lower Alzheimer’s rates in populations consuming traditional plant-based diets. However, he omits that the same research showed fish consumption was protective against cognitive decline, sometimes more so than plant foods.

When examining the “Nigerian paradox”—where high apoE4 prevalence doesn’t correlate with high Alzheimer’s rates—Greger attributes protection to plant-based diets. Yet this pattern also appears in hunter-gatherer populations with substantial animal product intake, suggesting that unprocessed diets (regardless of plant-to-animal ratio), physical activity, and feast-famine cycles may be more relevant factors.

Soy and Breast Cancer

Greger’s treatment of soy and breast cancer overlooks significant nuances in the research. While he presents studies suggesting soy protects against breast cancer, he doesn’t disclose that:

• Protective effects observed in Asian populations often don’t replicate in Western populations
• Only about half of Asians (and fewer non-Asians) possess intestinal bacteria capable of converting soy isoflavones into equol, potentially limiting benefits
• Early-life soy exposure may be critical—adult consumption alone may not provide the same benefits
• Clinical trials have been largely disappointing in demonstrating cancer-protective effects
• Some studies suggest soy isoflavones may enhance breast cancer growth under certain conditions

Valid Concerns About Animal Products

Despite its biases, “How Not to Die” raises legitimate concerns about meat consumption that deserve attention.

Foodborne Infections and Zoonotic Diseases

Greger presents compelling evidence that meat can transmit various pathogens to humans:

• Urinary tract infections may originate from E. coli strains in chicken, particularly antibiotic-resistant varieties
• Yersinia contamination from pork can lead to autoimmune arthritis and increased Graves’ disease risk
• Hepatitis E virus, potentially present in about 10% of pig livers in American grocery stores, can survive temperatures reached in undercooked meat

However, it’s important to note that these risks are largely associated with industrial meat production. Humanely raised livestock from properly managed farms poses substantially lower infection risks—though Greger doesn’t acknowledge this distinction.

High-Temperature Cooking and Carcinogens

One of Greger’s most scientifically sound arguments concerns heterocyclic amines (HCAs)—carcinogens that form when muscle meat is cooked at high temperatures (above 275°F/125°C). Because HCA formation requires creatine, found only in muscle tissue, plant foods don’t produce these compounds even when overcooked.

Research consistently links HCAs to increased risk of breast, colon, esophageal, lung, pancreatic, prostate, and stomach cancers. The evidence is particularly strong for grilled, fried, and well-done meat.

Importantly, Greger offers practical solutions for meat eaters: low-temperature cooking methods like boiling, steaming, or slow cooking dramatically reduce HCA formation. This represents a harm-reduction approach rather than absolute prohibition.

Who Should Read This Book?

“How Not to Die” is best suited for readers who:

• Are considering transitioning to plant-based eating and want comprehensive information about potential benefits
• Possess critical thinking skills and are willing to fact-check claims against cited sources
• Understand that dietary science is complex and often contradictory
• Can separate valuable insights from methodological weaknesses
• Are interested in preventive health approaches beyond pharmaceutical interventions

The book is less appropriate for readers seeking unbiased, comprehensive nutritional guidance that fairly represents all dietary approaches.

Practical Takeaways Despite the Limitations

Even with its biases, “How Not to Die” offers valuable lessons:

Increase Whole Plant Foods

Regardless of whether you eliminate animal products, increasing consumption of vegetables, fruits, legumes, whole grains, nuts, and seeds offers well-documented health benefits. Few nutrition experts dispute that most people would benefit from eating more unprocessed plant foods.

Question Food Industry Influence

Greger’s skepticism about profit-driven food and pharmaceutical industries is well-founded. Being an informed consumer means recognizing that commercial interests often conflict with public health.

Emphasize Prevention

The book’s core message—that lifestyle choices powerfully influence disease risk—is valuable. While not all diseases are preventable through diet alone, many chronic conditions are indeed influenced by what we eat.

Consider Food Quality and Preparation

Whether eating plants or animals, quality matters. Unprocessed foods, appropriate cooking methods, and attention to sourcing can significantly impact health outcomes.

The Bottom Line

“How Not to Die” represents both the best and worst of nutrition advocacy literature. Its extensive research compilation and passionate argument for plant-based eating have undoubtedly inspired positive dietary changes in many readers. The book effectively challenges the Standard American Diet and questions profit-driven healthcare approaches.

However, its selective citation of evidence, occasional misrepresentation of research findings, and oversimplification of complex nutritional science undermine its credibility as an unbiased resource. Readers who approach the book critically—fact-checking claims, seeking contradictory evidence, and recognizing its inherent biases—can extract valuable insights while avoiding its pitfalls.

Dr. Greger’s mission to democratize nutritional information is commendable, and his work has undoubtedly educated millions about the potential of food as medicine. Yet true empowerment comes not from accepting any single dietary dogma, but from developing the critical thinking skills to evaluate nutritional claims—including those in “How Not to Die”—with healthy skepticism.

For those interested in plant-based eating, this book provides motivation and extensive references for further research. For those seeking comprehensive, balanced nutritional guidance, it should be one resource among many, always cross-referenced against current scientific consensus and evaluated through a critical lens.

If you’re considering significant dietary changes based on this or any book, consulting with a qualified healthcare provider or registered dietitian can help ensure your approach meets your individual nutritional needs and health circumstances.

Sources:

• PubMed Central – National Institutes of Health
• JAMA – Journal of the American Medical Association
• NutritionFacts.org – Dr. Michael Greger’s Website
• Centers for Disease Control and Prevention
• Nature – International Journal of Science