When you’re in the health profession, as we are, you learn that every medical issue is equally as important as another. If you’re suffering from condition X, then that’s your priority: It’s what influences your world and that of those around you. Although we can cite statistics for prevalence and severity, we also know that it’s a dangerous game to imply that any one disease is more significant than any other. Some are life-threatening, some are not. But all diseases are life-changing. And that’s why we have chosen to cover so many topics, situations, and conditions in this book: because living in the biological cocktail of our bodies, a lot of different things can happen at different stages of our lives.
That said, we know full well that cancer is a hot-button medical issue. It’s an ugly, hard, and potentially deadly disease that has affected just about every single person in some form or fashion. And it’s a scary one. We have all seen—or lived with—the effects of cancer, and have borne witness to how it can very quickly or very slowly change our lives.
Cancer is a complex disease, very much dependent on the type, stage, location, treatment methods, and how those factors interact with each person’s body. So please understand this chapter is not meant to imply that eating certain foods can cure or all-out prevent cancer. It’s also not to say that you can stave off the nastiness of the disease by swigging down daily doses of spinach smoothies.
That’s because, like many diseases, so many factors play a role in the development of cancer, from genetic predispositions to lifestyle choices (smoking and excessive sun are two of the biggies, of course). And it certainly should go without saying that staying up on your diagnostics (like colon and breast cancer screenings) can help with early detection. This won’t prevent cancer per se, but can help thwart its development via early treatment.
But we are here to say that you can take steps to help decrease your risk of developing cancer through nutrition. Many foods and nutrients have been linked to lower cancer rates because of the role they play in the body. In fact, an analysis of research by Cancer Research UK indicates just a few lifestyle changes—including maintaining a healthy body weight, eating a healthy diet (similar to the When Way), cutting back on alcohol, not smoking, enjoying the sun safely, and keeping active—can prevent 4 in 10 cancers.1 And according to a 2018 study, more than 40 percent of cancers in the United States are preventable, while at least a third of preventable cancer deaths can be avoided through changes in diet and physical activity.2
The simple addition of these two lifestyle changes can really radically reduce the risk of death in people with cancer. For example, for those with breast cancer, eating five or more servings a day of fruits and veggies and getting 30 minutes of physical activity six days a week reduces the risk of death by about 50 percent over 10 years.3 Yes, you read that right.
A quick look at how this works: A couple systems can help fortify your body against the development of cancer cells. The main driver: the efficiency and power of your immune system. Your body is filled with immune cells that work like a security system; their job is to identify any foreign cells that can appear in your body.
The immune system works in ways that you probably already understand. When you have a cold or are sick from a virus, your immune cells recognize some nasty stuff causing problems and send in other immune cells to fight them. The result of that fight is what you see or feel—coughing, runny nose, inflammation, fever, and things of that sort. You also might see it when you cut yourself or twist an ankle. Redness or swelling are a result of those immune cells identifying a problem and sending in cells to heal the area.
Cancer cells come from normal cells that mutate as a result of environmental and genetic stressors. If your immune cells can recognize cancer or a protein the cancer cell has on its surface as foreign—like a virus—it can attack and kill it. A strong immune system may be able to kill off cancerous cells, but that’s not always the case; some cancer cells are able to hide their proteins from the immune system while they grow and spread quickly. One way to keep your immune system in top form is to make sure your vitamin D levels stay high. Although it’s most known for maintaining strong bones, vitamin D plays a crucial role in your immune system’s ability to identify and root out harmful cells in your body.4
Another thing that can lead to cancer is the development of free radicals in the body. Free radicals are formed when oxygen interacts with certain molecules. They set off a chain reaction of damage affecting your DNA and cells. To fight these free radicals, your body needs inside-the-cell antioxidants, which bind to free radicals and then rid them from your body to stop damage from developing. Antioxidants we consume can increase the amount of that binding power inside your cells, and can be found in a variety of foods and nutrients, especially fruits and vegetables. Part of this power comes from inside-the-cell antioxidants (superoxide dismutase [SOD], catalase, and glutathione are major ones). Blueberries, blackberries, raspberries, and pomegranates are the fruits that are best at directly increasing in-the-cell antioxidants.5
At a Glance: Why You Need More Fruits and Veggies
| The Produce | Produces… |
| Kiwi | They’re power-packed with many anticancer compounds, such as vitamin C, vitamin E, lutein, and copper. |
| Berries | They’re ranked highest in increasing in-the-cell antioxidant power. |
| Apples | Studies suggest that people who have diets rich in apples have a lower risk of cancer. One reason may be that when apples ferment in the colon, chemicals that can fight the formation of cancer cells are produced.21 |
| Tomatoes (especially cooked) | They contain lycopene, a powerful polyphenol that seems to have anticancer properties. |
| Citrus fruits | They have been shown to cut the risk of mouth and throat cancers by half in people who eat them daily.22 |
| Garlic | It may inhibit tumor growth, and studies suggest that it can reduce the incidence of some cancers by a factor of two.23,24,25 |
| Cruciferous veggies | One study showed that women who ate the most cruciferous veggies (cabbage, broccoli, cauliflower, watercress, arugula, and Brussels sprouts) had a 50 percent lower risk of breast cancer than those who ate the least.26 But don’t microwave your broccoli: A Spanish study found that doing so may destroy 97 percent of its flavonoids.27 Sprouts, like broccoli sprouts, contain sulforaphane, an anticancer compound, in up to 50 times the quantity found in mature plants. But sprouts can become contaminated with bacteria, so scientists are still figuring out how to get the benefits without the risks. |
| Mushrooms | They’re good sources of selenium, which is linked to lower rates of cancer in some studies. |
MVPs: Vegetables are nature’s best protective medicine. They’re fortified with so many good-for-you compounds and nutrients that we could write about each one of them for pages and pages. When it comes to preventing or fighting cancer, it’s best to eat them raw or lightly cooked (sautéed in extra-virgin olive oil is our favorite). The best types for fighting cancer include allium vegetables (like garlic, onions, and leeks), carrots, cruciferous veggies (think broccoli and cauliflower), and cooked tomatoes. They’re all packed with substances such as isoflavones, lycopene, selenium, sulfur-containing compounds, flavonoids—and that’s not even mentioning the vitamins! See the chart on this page for the specific effect each has on cancer rates. If there’s one thing you can do to help reduce your risk, it’s to make a conscious effort to cover more of your plate with veggies (and fruits are excellent as well!).
Key Players: Coffee and tea may be helpful in fending off cancer; both are full of antioxidants, polyphenols, and flavonoids that have been linked with lower risk of the disease. In fact, research links coffee consumption with decreased rates of both liver and endometrial cancer.6 Researchers at the National Cancer Institute found that those who drink four or more cups of coffee a day (regular or decaf, black please, and through a filter) have a 15 percent lower risk of colon cancer than those who do not drink coffee.7 And other studies showed that women who drank at least two cups of black tea a day had a 32 percent lower risk of ovarian cancer than those who drank one or none.8
Cut From the Team: Red and processed meat (ham, bacon, salami, sausage). There may be several reasons why evidence links red and processed meats (pork is considered red meat) to big-time increases in rates of cancer. But scientists tend to point to the chemicals within them. For example, red meat contains a naturally occurring red pigment called heme, which could damage cells in the body that may be linked to development of cancer. And chemicals called nitrates (used to preserve processed meat) can be converted to potentially cancer-causing chemicals. Many red meats are also cooked at high temperatures when they’re grilled or barbecued. This process can spark the production of cancerous chemicals, like acrylamide and heterocyclic amines.9 (Cooking in or marinating with olive oil, beer, or wine may help inhibit the development of these chemicals.10,11,12) The World Health Organization (WHO) lists red meat as probably carcinogenic to humans.13
By the way, unprocessed cooked white meats like chicken and fish are not linked to an increase in cancer. Eggs, which are rich in choline, on the other hand, have been linked to prostate cancer, and researchers hypothesize that the pro-inflammatory chemical trimethylamine N-oxide (TMAO, made by gut bacteria from choline and lecithin in eggs and carnitine in meat) may be partly responsible.14,15 So cutting both red meat and eggs may be a good idea. We may get a probiotic or substance that reduces bacterial production of TMAO.
| SUB OUT… | SUB IN… |
| Sprinkling sugar on your cereal | Simple sugars feed cancer growth. Instead, top cereal (or better yet, oatmeal) with blueberries, which provide sweetness as well as healthy antioxidants. |
| White flour crackers | Carrots, which contain beta-carotene and other compounds associated with a decreased risk of brain and neck cancers.16 Or sliced cucumbers. Or any cruciferous veggie—the more you eat, the less your cancer likelihood. |
| Red and processed meats like beef, pork, and sausage | White meat like chicken and fish. |
| Sugar in your tea | A slice of ginger as tea brews. A number of studies show that gingerroot has cancer-fighting properties.17,18 |
| Bacon breakfast sandwiches | Bran cereal. It’s one of the richest sources of fiber, which can help reduce the risk of colon cancer.19 Or avocado slices on 100 percent whole wheat toast, which has healthy fat and fiber. |
| Processed salad dressing | Balsamic vinegar and extra-virgin olive oil. In a study of 4,000 women, those on a Mediterranean diet (rich in olive oil) had 68 percent lower rates of breast cancer than those on a low-fat diet (with saturated fat as the main fat).20 |