Globally, cardiovascular disease kills roughly one in every three people (1), with cancer killing one in every six (2). In the United States, about half have cardiovascular disease (3), a third will get cancer (4), and more than a third will get diabetes (5), with nearly 60% of all Americans dying from one of these three diseases (3-5).
Meanwhile, global spending for prescription drugs is surpassing $1 trillion annually, with the US accounting for about one-third of this market (6). Part of the reason we spend so much money on pharmaceuticals is because many people have been conditioned to believe that the diseases we get and die from can largely be blamed on our genes. But for most of the leading causes of death, genes are only responsible for about 10 to 20 percent of our risk.
The best proof we have of this comes from looking at the health outcomes of people who move to countries where people have very different genetic backgrounds. While rates of heart disease and major cancers can vary up to 100-fold across populations around the globe, when people move to countries with different lifestyle habits, their rates of disease almost always begin to match those of their new country. If these diseases were primarily genetic, adopting a new lifestyle would have little impact (7).
“The major causes of chronic diseases are known, and if these risk factors were eliminated, at least 80% of all heart disease, stroke and type 2 diabetes would be prevented; over 40% of cancer would be prevented” (8).
— World Health Organization
In other words, while our genes can be a factor, the lifestyle choices we make are usually far more important.
More than 60% of all global deaths are due to chronic diseases and conditions such as cardiovascular disease, type 2 diabetes, obesity, and certain cancers, with poor diet considered a major contributory factor in all of them (9). Global health authorities concur that the leading cause of death worldwide is also diet, even beating out smoking (10).
The Global Burden of Disease Study (GBDS), the largest study of risk factors for disease in history, concluded that the number one cause of premature death in the United States, and the number-one cause of disability, is the standard American diet (11).
Also known as the standard Western diet, this pattern of eating is generally characterized by high intakes of meat, dairy products, eggs, fried foods, refined grains, and refined sugars, with low intakes of vegetables, fruits, whole grains, legumes, nuts and seeds.
Despite the fact that poor diet is known to be the leading cause of death worldwide (10), most people are confused about what foods promote good health and which foods can destroy it. For example, far more people aim to eat a “low-carb” diet than simply eat less of the foods that lie at the root of many of the most common chronic diseases (12).
As explored in The Game Changers, this confusion is no coincidence. Backed by billions of dollars in profits and taxpayer subsidies, the industries that create many of the world’s most harmful products churn out slick advertising campaigns, fund misleading studies, and grease the hands of compliant politicians, doing everything in their power to confuse the masses. More than half a century ago, Big Tobacco laid the foundation for this strategy, using athletes, soldiers, and even doctors as spokespeople (“More doctors smoke Camels than any other cigarette”). And then, when the deadly consequences of smoking started becoming known to the public, funding their own studies to “prove” smoking didn’t really cause cancer (13-15).
Today’s equivalent are the large food corporations and fast food retailers, who use the exact same playbook to confuse the public about the dangers of the products they profit most from (14).
Unfortunately, the healthiest foods have virtually no way to compete with the corporate giants, which have billions of dollars of funding to market and promote their products. The U.S. government, for example, spends $38 billion each year to subsidize the meat and dairy industries, but only $17 million (i.e., 0.04 percent of that) each year to subsidize fruits and vegetables. A $5 Big Mac would cost $13 if the retail price included hidden expenses that meat producers offload onto society (16).
Perhaps more disturbing is the way these multi-billion dollar industries infiltrate the scientific world, covertly funding countless studies that cast doubt upon what global health authorities agree are the most important elements of a healthy diet (17).
Despite recent diet trends that promote eating more animal products while avoiding grains and numerous types of fruits and vegetables, the Global Burden of Disease Study mentioned above — which involved nearly 500 researchers from more than 300 institutions in 50 countries and examined nearly 100,000 data sources (18)— concluded that the top four foods we need to consume more of in order to reduce our overall risk of death are fruits, nuts/seeds, vegetables, and whole grains. (Unfortunately the researchers didn’t look at legume intake (10), which may be the most important dietary predictor of survival in older people from around the globe (19).)
All told, the GBDS calculated that roughly 1 in every 5 deaths worldwide could be potentially saved if human beings simply ate more of these unrefined plant foods (20).
Unsurprisingly, the same study concluded that processed meats including bacon, bologna, ham, and hot dogs — which are classified as a Group 1 carcinogen by the World Health Organization (21) — did not make the list of life-saving foods, and were found to be responsible for 800,000 deaths annually, four times more than those who die from illicit drug use (20).
But the threat of cancer posed by animal-based foods goes far beyond processed meats.
Findings from the largest forward-looking study on diet and cancer in human history revealed that eating just one-quarter of a chicken breast per day increases the risk of some of the fastest growing cancers, like lymphomas and leukemias, by up to 280% (22). And a 2015 Harvard meta-analysis found that men consuming just five eggs per week increased their risk for a lethal form of prostate cancer by 47 percent (23). All told, research has shown that people who eat a diet high in animal protein (including red meat, poultry, fish, dairy and eggs) have more than a 400% increased risk of dying from cancer (24).
Meanwhile, people who simply avoid meat experience half the risk of colon cancer and one third the risk of prostate cancer (25).
Cancer refers to diseases where abnormal cells multiply uncontrollably, or simply won’t die. These cells often invade nearby tissues, inflicting more and more damage until, if left unchecked, they eventually shut down our entire life support system. As a result, cancer is the second leading killer in both the US and worldwide, responsible for one in every six human deaths (2,26).
Cancer thrives when oxidative stress activates chronic inflammation, which can damage or mutate our cellular DNA, transforming a normal cell into a tumor cell (27).
If some of this sounds familiar, you’re right. As we discussed in The Plant-Based Advantage, Animal foods — including processed, red, and white meat, as well as fish, dairy, and eggs — contain (or help create) a wide range of pro-inflammatory constituents, including polycyclic aromatic hydrocarbons and heterocyclic amines, each of which “contribute to inflammation, oxidation, and carcinogenesis” (28).
Making matters worse, animal foods are incredibly low in anti-inflammatory constituents, including the powerful antioxidants that help protect us from oxidative stress and chronic inflammation. On average, animal foods contain less than 2% of the antioxidant content of plants (29).
The protein found in animal foods also puts us at risk for cancer. As Dr. Walter Willett, former Chair of Nutrition at Harvard, explains in the The Game Changers, “The amino acids that come from animal sources tend to make our cells rev up and multiply faster. For example, there is accumulating evidence that high consumption of proteins from dairy sources is related to a higher risk of prostate cancer. That chain of cancer causation actually seems pretty clear.”
While cancer may be the most frightening diagnosis to receive, cardiovascular disease, which includes heart disease, stroke and hypertension (also known as high blood pressure), is the world’s number-one killer, claiming twice as many lives as cancer (1,2). In the US, about half of all people have it, and one in four will die from heart disease (3,30).
Here again, the protein and pro-inflammatory constituents of animal foods appear to play a central role.
A 2016 cohort study led by Harvard involving 131,342 participants found that every 10% increase in calories from animal protein led to a corresponding 8% increased risk of dying from cardiovascular disease, and concluded that “high animal protein intake was positively associated with cardiovascular mortality and high plant protein intake was inversely associated with all-cause and cardiovascular mortality” (31).
Another major cohort study involving more than 81,000 participants, published in the International Journal of Epidemiology, found that those eating the most protein from meat versus those eating the least had a 61% increased risk of cardiovascular death, while those eating the most protein from nuts and seeds experienced a 40% reduction in risk (32).
All told, simply avoiding animal products can reduce a man's risk of dying from heart disease by 55% (25).
Cardiovascular disease sets in when the arteries that supply blood and oxygen to our heart, brain or other organs become constricted or clogged with fatty material called plaque.
As referenced in The Plant-Based Advantage, a single animal-based meal can constrict our arteries by 40% just two hours after consuming it. Cardiovascular disease takes hold when this assault on our arteries continues day after day, year after year, until they become so stiff and narrow that blood flow to our hearts and brains becomes restricted. This process sets the stage for pieces of unstable plaque to break off and block blood flow to one of our arteries, at which point we may suffer a heart attack or stroke.
Many factors play a role in why animal foods aren’t good for your cardiovascular system. These include the numerous compounds and molecules that come from foods like meat — including endotoxins, trimethylamine N-oxide (TMAO), heterocyclic amines (HCAs), and heme iron — which can inflame our arteries and lead to the formation of plaques (28,33). Heme iron is so potentially damaging that just eating one more milligram per day is associated with a 27 percent increase in risk of coronary heart disease (34). To put that in perspective, a single hamburger patty can contain two milligrams of heme iron or more (35-37).
Meanwhile, a large body of evidence shows that plants have the opposite effect, improving arterial function via a completely different set of constituents, including antioxidants and plant-sourced nitrates, which soothe the inflammation that can lead to cardiovascular disease while improving blood flow to our heart, brain and other organs (38,39).
Taking all of this into account, it may come as no surprise that a healthy plant-based diet is not only effective at preventing cardiovascular disease, but is the only diet that has ever been clinically proven to actually reverse it (40,41).
“It's not one set of dietary guidelines for improving your performance as an athlete, another one for reversing heart disease, a different one for reversing diabetes, a different one for reversing prostate cancer. It's the same for all of them.”
— Dr. Dean Ornish in The Game Changers
A review of multiple major cohort studies published in Nutrients concluded that “Vegetarian diets confer protection against cardiovascular diseases, cardiometabolic risk factors, some cancers and total mortality. Compared to lacto-ovo-vegetarian diets, vegan diets seem to offer additional protection for obesity, hypertension, type-2 diabetes, and cardiovascular mortality.” (25)
Conversely, researchers studying lapsed vegetarians found that those who started eating meat at least once a week experienced more than double the increase in odds of heart disease, stroke, and diabetes, triple the increase for weight gain, and an associated 3.6-year drop in life expectancy (42).
Plant-based diets have also been shown to improve symptoms, often dramatically, for people suffering from numerous inflammatory diseases and conditions, including rheumatoid arthritis (43), multiple sclerosis (44,45), inflammatory bowel diseases (46,47), and asthma (48,49).
There even seems to be emerging evidence that a plant-based diet could also help prevent and/or reduce symptoms of dementia, including Alzheimer’s, for many the most feared disease of all. As a result, the 2014 “Dietary and Lifestyle Guidelines for the Prevention of Alzheimer’s Disease” published in the journal Neurobiology of Aging, recommended that “vegetables, legumes (beans, peas, and lentils), fruits, and whole grains should replace meats and dairy products as primary staples of the diet.” (50,51)
Factoring in the myriad health benefits that a largely unrefined, plant-based diet can provide, it’s little wonder why the animal foods industry, and the pharmaceutical companies who profit from its effects, fight so hard to maintain the status quo, doing everything they can to keep people in the dark about how much power we have over our own health.
Fortunately, there’s one major corporate sector that actually benefits from keeping people healthy: the insurance industry.
In their official journal, Kaiser Permanente, the largest managed-care organization in the US, recently advised their nearly 15,000 physicians that “healthy eating may be best achieved with a plant-based diet, which we define as a regimen that encourages whole, plant-based foods and discourages meats, dairy products, and eggs...” They add, “Too often, physicians ignore the potential benefits of good nutrition and quickly prescribe medications instead of giving patients a chance to correct their disease through healthy eating and active living…Physicians should consider recommending a plant-based diet to all their patients.” (52)
This simple statement should strike fear into the hearts of those who profit from unhealthy foods, and bring hope to the hearts of those who feel powerless in the face of their own health, and the health of those they care about The science of nutrition has never been clearer about which foods lay the foundation for disease, and which foods lay the foundation for optimal health.
The choice, and the power, is ours.
(1) World Health Organization. Cardiovascular diseases (CVDs). 2017 May 17.
(2) World Health Organization. Cancer. 2018, Sept 12.
(3) Benjamin EJ, Muntner P, Alonso A, Bittencourt MS, Callaway CW, et al. American Heart Association Council on Epidemiology and Prevention Statistics Committee and Stroke Statistics Subcommittee. Heart Disease and Stroke Statistics-2019 Update: A Report From the American Heart Association. Circulation. 2019 Mar 5;139(10):e56-e528.
(4) American Cancer Society. Lifetime risk of developing or dying from cancer. 2018 Jan 4.
(5) Gregg EW, Zhuo X, Cheng YJ, Albright AL, Narayan KM, Thompson TJ. Trends in lifetime risk and years of life lost due to diabetes in the USA, 1985-2011: a modelling study. Lancet Diabetes Endocrinol. 2014 Nov;2(11):867-74.
(6) Aitken M, Johns Hopkins Bloomberg School of Public Health. The trillion dollar market for medicines: characteristics, dynamics and outlook. IMS Institute for Healthcare Informatics. 2014 Feb 24.
(7) Willett WC. Balancing life-style and genomics research for disease prevention. Science. 2002 Apr;296(5568):695-8.
(8) World Health Organization. Overview - Preventing chronic diseases: A vital investment. Misunderstanding #4: Chronic diseases can't be prevented.
(9) Bloom DE, Cafiero ET, Jané-Llopis E, Abrahams-Gessel S, Bloom LR, Fathima S, Feigl AB, Gaziano T, Mowafi M, Pandya A, Prettner K, Rosenberg L, Seligman B, Stein AZ, Weinstein C. (2011). The Global Economic Burden of Noncommunicable Diseases. Geneva: World Economic Forum.
(10) GBD 2017 Diet Collaborators. Health effects of dietary risks in 195 countries, 1990-2017: A systematic analysis for the Global Burden of Disease Study 2019. Lancet. 2019 Apr;393(10184):1958-72.
(11) Mokdad AH, Ballestros K, Echko M, et al. The State of US Health, 1990-2016: Burden of Diseases, Injuries, and Risk Factors Among US States. JAMA. 2018 Apr;319(14):1444-72.
(12) Santos I, Sniehotta FF, Marques MM, Carraça EV, Teixeira PJ. Prevalence of personal weight control attempts in adults: a systematic review and meta-analysis. Obes Rev. 2017 Jan;18(1):32–50.
(13) Ong EK, Glantz SA. Tobacco industry efforts subverting International Agency for Research on Cancer’s second-hand smoke study. Lancet. 2000 Apr;355:1253-9.
(14) Moodie R, Stuckler D, Monteiro C, Sheron N, Neal B, Thamarangsi T, Lincoln P, Casswell S. Profits and pandemics: prevention of harmful effects of tobacco, alcohol, and ultra-processed food and drink industries. Lancet. 2013 Feb;381(9867):670-9.
(15) Jackler RK, Ayoub NF. ‘Addressed to you not as a smoker… but as a doctor’: doctor‐targeted cigarette advertisements in JAMA. Addiction. 2018 Jul;113(7):1345-63.
(16) Joshi I, Param S, Irene, Gadre M. Saving the planet, The market for sustainable meat alternatives. Sutardja Center for Entrepreneurship & Technology Technical Report. 2015 Nov.
(17) Fabbri A, Holland TJ, Bero LA. Food industry sponsorship of academic research: investigating commercial bias in the research agenda. Pub Health Nutr. 2018 Dec;21(18):3422-30.
(18) Das P, Samarasekera U. The story of GBD 2010: a “super-human” effort. Lancet. 2012 Dec;380(9859):2067-70.
(19) Darmadi-Blackberry I, Wahlqvist ML, Kouris-Blazos A, Steen B, Lukito W, Horie Y, Horie K. Legumes: the most important dietary predictor of survival in older people of different ethnicities. Asia Pac J Clin Nutr. 2004 Feb;13(2):217-20.
(20) Lim SS, Vos T, Flaxman AD, et al. A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012 Dec;380(9859):2224-60.
(21) International Agency for Research on Cancer, World Health Organization. Q&A on the carcinogenicity of the consumption of red meat and processed meat. 2015.
(22) Rohrmann S, Linseisen J, Jakobsen MU, Overvad K, Raaschou-Nielsen O, et al. Consumption of meat and dairy and lymphoma risk in the European Prospective Investigation into Cancer and Nutrition. Int J Cancer. 2011 Feb;128(3):623-34.
(23) Keum N, Lee DH, Marchand N, Oh H, Liu H, Aune D, Greenwood DC, Giovannucci EL. Egg intake and cancers of the breast, ovary and prostate: a dose-response meta-analysis of prospective observational studies. Br J Nutr. 2015 Oct 14;114(7):1099-107.
(24) Levine ME, Suarez JA, Brandhorst S, Balasubramanian P, Cheng CW, Madia F, Fontana L, Mirisola MG, Guevara-Aguirre J, Wan J, Passarino G, Kennedy BK, Wei M, Cohen P, Crimmins EM, Longo VD. Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population. Cell Metab. 2014 Mar;19(3):407-17.
(25) Le LT, Sabaté J. Beyond Meatless, the Health Effects of Vegan Diets: Findings from the Adventist Cohorts. Nutrients. 2014 Jun;6(6):2131-47.
(26) American Cancer Society. Cancer Facts & Figures 2019. Atlanta: American Cancer Society; 2019.
(27) Visconti R, Grieco D. New insights on oxidative stress in cancer. Curr Opin Drug Discov Devel. 2009 Mar;12(2):240-5.
(28) Hever J, Cronise RJ. Plant-based nutrition for healthcare professionals: implementing diet as a primary modality in the prevention and treatment of chronic disease. J Geriatr Cardiol. 2017 May;14(5):355-68.
(29) Carlsen MH, Halvorsen BL, Holte K, Bøhn SK, Dragland S, Sampson L, Willey C, Senoo H, Umezono Y, Sanada C, Barikmo I, Berhe N, Willett WC, Phillips KM, Jacobs DR Jr, Blomhoff R. The total antioxidant content of more than 3100 foods, beverages, spices, herbs and supplements used worldwide. Nutr J. 2010 Jan;9:3.
(30) Centers for Disease Control and Prevention, National Center for Health Statistics. Multiple Cause of Death 1999-2015 on CDC WONDER Online Database, released December 2016. Data are from the Multiple Cause of Death Files, 1999-2015, as compiled from data provided by the 57 vital statistics jurisdictions through the Vital Statistics Cooperative Program.
(31) Song M, Fung TT, Hu FB, Willett WC, Longo VD, Chan AT, Giovannucci EL. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med. 2016 Oct;176(10):1453-63.
(32) Tharrey M, Mariotti F, Mashchak A, Barbillion P, Delattre M, Fraser GE. Patterns of plant and animal protein intake are strongly associated with cardiovascular mortality: the Adventist Health Study-2 cohort. Int J Epid. 2018 Oct;47(5):1603-12.
(33) Erridge C, Attina T, Spickett CM, Webb DJ. A high-fat meal induces low-grade endotoxemia: evidence of a novel mechanism of postprandial inflammation. Am J Clin Nutr. 2007 Nov;86(5):1286-92.
(34) Yang W, Li B, Dong X, Zhang XQ, Zeng Y, Zhou JL, Tang YH, Xu JJ. Is heme iron intake associated with risk of coronary heart disease? A meta-analysis of prospective studies. Eur J Nutr. 2014 Mar;53(2):395-400.
(35) Young LR, Nestle M. Portion sizes and obesity: responses of fast-food companies. J Public Health Policy. 2007 Jul;28(2):238-48.
(36) Cross AJ, Harnly JM, Ferrucci LM, Risch A, Mayne ST, Sinha R. Developing a heme iron database for meats according to meat type, cooking method and doneness level. Food Nutr Sci. 2012 Jul;3(7):905-13.
(37) HealthLinkBC. Iron in Foods. Nutrition Series - Number 68d. Feb 2017.
(38) Leopold JA. Antioxidants and Coronary Artery Disease: From Pathophysiology to Preventive Therapy. Coron Artery Dis. 2015 Mar;26(2):176-83.
(39) Raubenheimer K, Bondonno C, Blekkenhorst L, Wagner KH, Peake JM, Neubauer O. Effects of dietary nitrate on inflammation and immune function, and implications for cardiovascular health. Nutr Rev. 2019 Aug;77(8):584-99.
(40) Satija A, Hu FB. Plant-based diets and cardiovascular health. Trends Cardiovasc Med. 2018 Oct;28(7):437-41.
(41) Kahleova H, Levin S, Barnard N. Cardio-Metabolic Benefits of Plant-Based Diets. Nutrients. 2017 Aug;9(8):848.
(42) Singh PN, Arthur KN, Orlich MJ, et al. Global epidemiology of obesity, vegetarian dietary patterns, and noncommunicable disease in Asian Indians. Am J Clin Nutr. 2014 Jul;100(1):359S-64S.
(43) Alwarith J, Kahleova H, Rembert E, Yonas W, Dort S, Calcagno M, Burgess N, Crosby L, Barnard D. Nutrition interventions in rheumatoid arthritis: The potential use of plant-based diets. A review. Front Nutr. 2019 Sep;6:141.
(44) Kadoch MA. Is the treatment of multiple sclerosis headed in the wrong direction? Can J Neurol Sci. 2012 May;39(3):405.
(45) Swank RL, Goodwin J. Review of MS patient survival on a Swank low saturated fat diet. Nutrition. 2003 Feb;19(2):161-2.
(46) Chiba M, Abe T, Tsuda H, et al. Lifestyle-related disease in Crohn's disease: relapse prevention by a semi-vegetarian diet. World J Gastroenterol. 2010 May;16(20):2484-95.
(47) Chiba M, Nakane K, Tsuji T, et al. Relapse Prevention in Ulcerative Colitis by Plant-Based Diet Through Educational Hospitalization: A Single-Group Trial. Perm J. 2018 Jun;22:17-167.
(48) Lindahl O, Lindwall L, Spångberg A, Stenram A, Ockerman PA. Vegan regimen with reduced medication in the treatment of bronchial asthma. J Asthma. 1985;22(1):45-55.
(49) Wood LG, Garg ML, Smart JM, Scott HA, Barker D, Gibson PG. Manipulating antioxidant intake in asthma: a randomized controlled trial. Am J Clin Nutr. 2012 Aug;96(3):534-43.
(50) Giem P, Beeson WL, Fraser GE. The incidence of dementia and intake of animal products: preliminary findings from the Adventist Health Study. Neuroepidemiology. 1993 May;12(1):28-36.
(51) Barnard ND, Bush AI, Ceccarelli A. Dietary and lifestyle guidelines for the prevention of Alzheimer's disease. Neurobiol Aging. 2014 Sep;35 Suppl 2:S74-8
(52) Tuso PJ, Ismail MH, Ha BP, Bartolotto C. Nutritional update for physicians: plant-based diets. Perm J. 2013 Spring;17(2):61-6.
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