Optimizing Health

Genetics vs. Lifestyle

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% 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).

In other words, while our genes can be a factor, the lifestyle choices we make are usually far more important.

The Leading Cause of Death

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.

Well-Funded Confusion

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% 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).

Eat More Plants

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).

Animal Foods and Cancer

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% (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).

How Cancer Works

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.”

Animal Foods and Cardiovascular Disease

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).

How Cardiovascular Disease Works

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% 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).

Diabetes, Obesity, and More

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)

Our Choice, Our Power

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.