How Not to Die: Discover the Foods Scientifically Proven to Prevent and Reverse Disease

by Michael Greger

You can measure your own oral-anal transit time by eating some beets and noting when your stools turn pink. If that takes less than twenty-four to thirty-six hours, you’re probably meeting the healthy half-pound target.

Constipation can be considered a nutrient-deficiency disease, and that nutrient is fiber.

For many years, phytates were maligned as inhibitors of mineral absorption, which is why you might have heard advice to roast, sprout, or soak your nuts to get rid of the phytates. In theory, this would allow you to absorb more minerals, such as calcium.

But more recently, in light of actual human data, phytates’ image has undergone a complete makeover.40 Those who eat more high-phytate foods actually tend to have a greater bone mineral density,41 less bone loss, and fewer hip fractures.

When you eat whole grains, beans, nuts, and seeds, phytates are rapidly absorbed into the bloodstream and readily taken up by tumor cells. Tumors concentrate these compounds so efficiently that phytate scans can be used to trace the spread of cancer within the body.

The healthiest sources of iron are whole grains, legumes, nuts, seeds, dried fruits, and green, leafy vegetables. Avoid drinking tea with meals, as that can inhibit iron absorption. Consuming vitamin C–rich foods can improve iron absorption. The amount of vitamin C in a single orange can enhance iron absorption as much as three- to sixfold, so those trying to boost their iron absorption should reach for some fruit instead of a cup of tea.

The primary risk factors include smoking, heavy alcohol consumption, and gastroesophageal reflux disease (GERD, also called acid reflux), in which acid from the stomach gurgles up into the esophagus, burning the inner layer and causing inflammation that can eventually lead to cancer. Besides avoiding tobacco and alcohol (even light drinking appears to increase risk),100 the most important thing you can do to prevent esophageal cancer is to eliminate acid reflux disease—and that can often be accomplished through diet.

Chronic inflammation caused by acid reflux can lead to Barrett’s esophagus, a precancerous condition that involves changes in the esophageal lining.102 To prevent adenocarcinoma, the most common type of esophageal cancer in the United States, this sequence of events must be stopped—and that means halting acid reflux in the first place.

Over the past two decades, about forty-five studies have examined the link between diet, Barrett’s esophagus, and esophageal cancer. The most consistent association with cancer was the consumption of meat and high-fat meals.

How does this happen? Within five minutes of eating fat, your sphincter muscle at the top of your stomach—which acts like a valve to keep down food inside the stomach—relaxes, allowing acids to creep back up into the esophagus.

Billions of dollars are spent on medications to alleviate heartburn and acid reflux by reducing the amount of stomach acid produced, but these drugs can contribute to nutrient deficiencies and increase the risk of pneumonia, intestinal infections, and bone fractures.

The protection afforded by plant-based eating may not be based just on the foods that are reduced, though. Centering your diet around antioxidant-rich plant foods may cut in half your odds of esophageal cancer.115 The most protective foods for cancer at the esophagus-stomach border appear to be red, orange, and dark-green leafy vegetables, berries, apples, and citrus fruits,116 but all unprocessed plant foods have the advantage of containing fiber.

While fat intake is associated with increased risk of reflux, fiber intake appears to decrease that risk.117 High fiber intake may reduce the incidence of esophageal cancer by as much as one-third118 by helping to prevent the root cause of many cases of acid reflux: the herniation of part of the stomach up into the chest cavity.

If you regularly strain to push out stool, over time the increased pressure can push part of the stomach up and out of the abdomen, allowing acid to flow up toward the throat.

the pressure from straining at the toilet may herniate outpouchings from the wall of the colon, a condition known as diverticulosis. The increased abdominal pressure may also back up blood flow in the veins around the anus, causing hemorrhoids,

Our bodies were designed to expect an ever-flowing fiber stream, so it dumps such unwanted waste products as excess cholesterol and estrogen into the intestines, assuming they will be swept away. But if you aren’t constantly filling your bowels with plant foods, the only natural source of fiber, unwanted waste products can get reabsorbed and undermine your body’s attempts at detoxifying itself.

The latest recommendations from the World Health Organization favor the use of alcohol-based sanitizing rubs or gels over hand washing for routine disinfection of your hands throughout the day. (Products containing between 60 and 80 percent alcohol were found to be more effective than soap in every scientific study available for review.) The only time hand washing is preferable is when they are dirty or visibly contaminated with bodily fluids. For routine decontamination—that is, for all other times—alcohol-based products are the preferred method for hand sanitation.

attack and engulf pathogens directly, and natural killer cells that put your cells out of their misery if they become cancerous or infected with a virus. How do natural killer cells recognize pathogens and infected cells? They are often marked for destruction by antibodies, which are special proteins made by another type of white blood cell, known as B cells, that home in like smart bombs and stick to invaders.

Compared with the control group, people eating five or more servings of fruits and vegetables had an 82 percent greater protective antibody response to the vaccine—and this was after only a few months of eating just a few extra servings of fruits and vegetables a day.22 That is how much control the fork may exert over immune function.

No clinical studies (that is, studies on real people) on kale have been performed to date. Big Kale, it seems, has yet to muster the research dollars.

natural killer cells are a type of white blood cell that’s a vital member of the immune system’s rapid-response team against virus-infected and cancerous cells. They’re called natural killers because they don’t require prior exposure to a disease to be activated, unlike some other parts of the immune system that can only respond effectively after a history of exposure,

There are about two billion of these elite, special-ops fighters patrolling the bloodstream at any one time, but research suggests that you can bolster their ranks by eating blueberries.

(Considered the gold standard of research, a randomized, double-blind, placebo-controlled study is a trial in which neither the participants nor the researchers know who is receiving an experimental treatment and who is receiving a placebo until the end of the study.)

What do your friendly flora eat? Fiber and a certain type of starch concentrated in beans. These substances are called prebiotics. Probiotics are the good bacteria themselves, whereas prebiotics are what your good bacteria eat. So the best way to keep your good bacteria happy and well fed is to eat lots of whole plant foods.

When you eat fresh produce, you can get both pre- and probiotics into your gut. Fruits and veggies are covered with millions of lactic acid bacteria, some of which are the same types used in probiotic supplements.

Approximately 95 percent of all infections start in the mucosal (moist) surfaces, including the eyes, nostrils, and mouth.54 These surfaces are protected by antibodies called IgA (short for immunoglobulin, type A), which provide an immunological barrier by neutralizing and preventing viruses from penetrating into the body. The IgA in saliva, for instance, is considered the first line of defense against such respiratory-tract infections as pneumonia and influenza.55 Moderate exercise may be all it takes to boost IgA levels and significantly reduce the chance of coming down with flu-like symptoms.

nutritional yeast has a pleasant, cheese-like flavor. It tastes particularly good on popcorn.

Just as algae can be thought of as single-celled plants, yeast can be thought of as single-celled mushrooms. Thousands of edible mushrooms grow naturally, with worldwide annual commercial production in the millions of tons.71 But check the nutrition label on a carton of mushrooms and you won’t see much beyond some B vitamins and minerals. Is that all mushrooms have? No. What you don’t see listed is the array of unique myconutrients that may boost our immune function.

Studies have shown that up to 80 percent of the time, placing fresh chicken on a cutting board for a few minutes can transfer disease-causing bacteria.95 Then, if you put cooked chicken back on the same cutting board, there’s about a 30 percent chance that the meat will become recontaminated.

In a meat industry trade publication, an Alabama poultry science professor explained why we don’t have such a “heavy-handed” policy: “The American consumer is not going to pay that much. It’s as simple as that.” If the industry had to pay to make it safer, the price would go up. “The fact,” he said, “is that it’s too expensive not to sell salmonella-positive chicken.”

My book certainly couldn’t have caused more injury to Dr. Atkins than his own diet. You see, he died the year before, overweight and—according to his autopsy report—suffering from a history of heart attack, congestive heart failure, and hypertension.

Diabetes mellitus is characterized by chronically elevated levels of sugar in your blood. This is because either your pancreas gland isn’t making enough insulin (the hormone that keeps your blood sugar in check) or because your body becomes resistant to insulin’s effects. The insulin-deficiency disease is called type 1 diabetes, and the insulin-resistance disease is called type 2 diabetes.

Your digestive system breaks down the carbohydrates you eat into a simple sugar called glucose, which is the primary fuel powering all the cells in your body. To get from the bloodstream into your cells, glucose requires insulin. Think of insulin as the key that unlocks the doors to your cells to allow glucose to enter. Every time you eat a meal, insulin is released by your pancreas to help shuttle the glucose into your cells. Without insulin, your cells can’t accept glucose, and, as a result, the glucose builds up in your blood.

Type 1 diabetes is therefore treated with injections of insulin, a type of hormone-replacement therapy, to make up for the lack of production.

Doctors can actually measure the level of freely floating fat in the bloodstream. Normally, it’s between about one hundred and five hundred micromoles per liter. But people who are obese have blood levels between roughly six hundred and eight hundred.

Not all fats affect our muscle cells in the same way. For example, palmitate, the kind of saturated fat found mostly in meat, dairy, and eggs, causes insulin resistance. On the other hand, oleate, the monounsaturated fat found mostly in nuts, olives, and avocados, may actually protect against the detrimental effects of the saturated fat.

Reducing belly fat may be the best way to prevent prediabetes from turning into full-blown diabetes. Though calorie cutting has been the cornerstone of most weight-loss strategies, evidence suggests that the majority of individuals who lose weight by portion control eventually regain it. Starving ourselves almost never works long term.

Saturated fats may also be toxic to the cells in the pancreas that produce insulin. At around age twenty, the body stops making new insulin-producing beta cells. After that, if they are lost, they may be lost for good.49 Autopsy studies have shown that by the time type 2 diabetes is diagnosed later in life, you may have already killed off half your beta cells.50

Fruits and vegetables, on average, contain about 80–90 percent water. Just as fiber can bulk up the volume of foods without adding calories, so can water. Experiments have shown that people tend to eat the same amount of food at a meal, regardless of calorie count—probably because stretch receptors in the stomach send signals to the brain after a certain volume of food has been ingested. When much of that volume is a zero-calorie component like fiber or water, that means you can eat more food but gain less weight.

it is critically important to work with your doctor when radically improving your diet, because if they don’t reduce or eliminate your medications accordingly, your blood sugar levels or blood pressure may drop too low.)

there may be an even better tool than BMI that we can use to gauge the health risks of body fat. It’s called Waist-to-Height Ratio, or WHtR.120 Instead of a scale, grab a simple measuring tape. Stand up straight and take a deep breath, exhale, and let it all hang out. The circumference of your belly (halfway between the top of your hip bones and the bottom of your rib cage) should be half your height—ideally, less. If that measurement is more than half your height, it’s time to start eating healthier and exercising more regardless of your weight.

The results allow us to answer such questions as “How many lives could we save if people around the world cut back on soda?” The best answer? 299,521.3 So soft drinks and their empty calories don’t just fail to promote health—they actually seem to promote death. But apparently soda isn’t nearly as deadly as bacon, bologna, ham, and hot dogs.

Processed meat is blamed for the deaths of more than eight hundred thousand people every year. Worldwide, that’s four times more people than who die from illicit drug use.

Eating more whole grains could potentially save 1.7 million lives a year. More vegetables? 1.8 million lives. How about nuts and seeds? 2.5 million lives. The researchers didn’t look at beans, but of the foods they considered, which does the world need most? Fruit. Worldwide, if humanity ate more fruit, we might save 4.9 million lives.

The number-one risk factor for death in the world they identified is high blood pressure.6 Also known as hypertension, high blood pressure lays waste to nine million people worldwide every year.7 It kills so many people because it contributes to deaths from a variety of causes, including aneurysms, heart attacks, heart failure, kidney failure, and stroke.

The number-one source of sodium for American kids and teens is pizza.

There are three things you can do to shake the salt habit.69 First, don’t add salt at the table. (One out of three people may add salt to their food before even tasting it!)70 Second, stop adding salt when cooking. The food may taste bland at first, but within two to four weeks, the salt-taste receptors in your mouth become more sensitive, and food tastes better. Believe it or not, after two weeks, you may actually prefer the taste of food with less salt.71 Try any combination of such fantastic flavorings as pepper, onions, garlic, tomatoes, sweet peppers, basil, parsley, thyme, celery, lime, chili powder, rosemary, smoked paprika, curry, coriander, and lemon instead.72 Also, it’s probably a good idea to avoid eating out as much as possible. Even non-fast-food restaurants tend to pile on the salt.73 Finally, do what you can to avoid processed foods.

Try to buy foods with fewer milligrams of sodium on the label than there are grams in the serving size. For example, if it’s a 100 g serving size, the product should have less than 100 mg of sodium.

Alternatively, you can shoot for fewer milligrams of sodium per serving than there are calories.

Dr. Sacks had even shown that the more dairy vegetarians consumed, the higher their blood pressure appeared to rise.108 But he figured there was no point in calling for a diet he believed few would follow. This is a recurring theme in official dietary recommendations. Instead of simply telling you what the science shows and then letting you make up your own mind, experts patronize the population by advocating what they think is practical rather than ideal. By making the decision for you, they undermine those willing to make even greater changes for optimal health.