How Not To Feed Your Cancer

How Not To Feed Your Cancer

Whooli Chen

Your cancer is uniquely yours. Get to know it—so you can help deprive it of exactly what it needs to survive.

If you’re unlucky enough to have been diagnosed with cancer, you’ve fielded unhelpful advice from friends, relatives, and even strangers about a miracle or a secret or natural cure. There are also books and video series that will sell you the capital-T truth about cancer.

Are these people stupid, or evil? Absolutely not. In fact, they are often right, but in an incomplete way. They are palpating different parts of the elephant. They have each seen, or think they’ve seen, or heard of, a case of unusual recovery from cancer using unconventional treatment methods. Such events do occur.

Ask any oncologist and you’ll find that, like me over a career of two-plus decades, they’ll recall one or two. These cases are win-the-lottery rare. But I keep an eye out for them because unexpected recoveries are precious, every one worthy of serious scientific investigation.

Meanwhile, we now know that every cancer is unique and constantly changing, and every person bearing such an affliction is also one of a kind. So if you have cancer, copying what you heard may have worked for someone else is like picking last week’s winning lottery numbers—it is unlikely to work. But there are ways to think about cancer that can help you make the most of what you can do, and what your oncologist can do.

What you do matters in your treatment, but only so much.

Many of my patients can recall an unsatisfying encounter with an oncologist who asserted that diet doesn’t matter, exercise has no effect, and state of mind is unimportant. The metaphor at work here is that cancer is an invader that should be fought by highly trained outsiders. As the patient, your job is to allow the warriors to hack, burn, and poison, while you hang on for the ride of your life.

What’s forgotten in this approach is the person bearing the cancer, the person who wants the reins returned—who can make a real difference in the outcome.

I also see many patients who eschew chemo, surgery, radiation—who approach cancer “naturally.” This appeals to those who view cancer as an aberration, an outcome of our unnatural modern life, as well as people who are repelled by the industrialization of our medical establishment. Reset to a natural way of life, the thinking goes, and the body will undo cancer. Naturally. Green juice, medicinal mushrooms, botanicals, meditation.

I agree that simply thinking of these things is calming. But cancer, too, is a natural process, around for eons, and found everywhere in nature where multicellular creatures exist. Our bodies tend toward cancer, not away from it, and when cancer eventually arises, we need outside help from expert teams who have learned so much in the last few decades about how to cure cancer.

So I encourage my patients to change or expand their metaphors and use all the tools available. Diet, medications, surgery, supplements, exercise, and perhaps one of the most powerful ways not to feed your cancer: fasting. I’ll talk more about that in a moment.

Our bodies tend toward cancer, not away from it, and when cancer eventually arises, we need outside help from expert teams who have learned so much in the last few decades about how to cure cancer.

If you find out your health care practitioner gives every cancer patient the same program, run.

I’ll be blunt here. Anyone who recommends any single treatment—drug, supplement list, diet, whatever—for all cancers is a nitwit. Cancers differ in so many dimensions: within a single person across time, within a single person at various bodily sites, between people, between organs, across sex and age groups, and on and on. Why this is so is one of the great challenges facing the human intellect—and why you want the best team possible looking out for you. 

As an example of the diverse expression of malignancy, cancers are rare in children. But when they do arise they are typically raging wildfires of growth. Even so, most children diagnosed with a cancer are cured, even if the cancer is advanced. 

In contrast, the older someone gets, the more likely they are to have a cancer. For example, by age 80, almost all men harbor cancerous cells in their prostate gland. Cancers in the aged grow more slowly than those in children—so slowly that minimal treatment is required. But when advanced, the most common cancers in older adults are generally incurable. 

There are exceptions, as in the group of several dozen cancers called lymphomas. Most adults with fast-growing lymphomas are cured. Paradoxically, “indolent” lymphomas are likely to eventually take an adult’s life.

The variation continues down to the level of the single patient. One tumor can harbor different areas of vulnerability. Biopsy a tumor in two spots separated by an inch, and you may find differing and opposing drug vulnerabilities. What’s more, a tumor that is sensitive to a drug now may be resistant to the same drug in several months. 

Going even further down, to the molecular level, there’s the issue of what “causes” cancer. Again, variation is the theme. Some tumors are caused by viruses. Some by bacteria. Some by radiation, some by toxins (including many from natural sources). Some by too much food during gestation, some by too little. Some by who knows what. 

You get the idea. Cancer is protean. If your health care provider doesn’t grok that, flee.

The organ of origin (such as breast or colon) is less important than the genetic mutations in your tumor.

There are many types of breast cancer, for instance. Some breast cancers are more similar to ovarian cancer than to other breast cancers in their vulnerability to particular drugs. Tumors from the right side of the colon may respond to certain drugs differently than tumors from the left side of the colon.

If your oncologist is not sure how to treat your cancer, deep study of your tumor’s genetic mutations (these will be different than the mutations in your normal cells) can help. One such test is called “next generation sequencing.” Other tests, called “metabolomics,” can determine which genes in your tumor are turned on or off. “Sensitivity testing” can help determine which treatments might have the best effect on your cancer. None of these tests are perfect. But they can offer guidance when your oncology team is stuck. 

Get a second opinion. Far away.

It surprises most people to learn that your surgeon doesn’t diagnose your cancer. Nor does the radiologist who performs your needle biopsy. Your cancer is diagnosed by a doctor you will never meet: a pathologist. The pathologist slices, dices, and stains your biopsy specimen and, among other things, studies it under a microscope. Your oncologist uses the pathologist’s stated diagnosis to choose the right treatment for your cancer.

There’s a big problem with this. A certain, albeit small, percentage of cancer diagnoses are incorrect. That means you may have a different cancer altogether. This matters. The wrong treatment won’t work. Or you may not have cancer at all. 

So please ask for a second pathology opinion. In a faraway city—out of state is best. Politics matter in medicine. The person giving the second opinion might not dare step on the toes of a powerful colleague. 

New research shows that for humans, fasting during chemotherapy is safe, and seems to reduce side effects such as immune suppression and nausea. 

Get a PET scan before your tumor is removed or treated. You need to know what yours likes to eat.

A PET scan is a photograph of how your tumor uses glucose, or blood sugar. Most cancers love glucose but a few are indifferent. If your tumor lights up on PET scanning, your tumor loves glucose and you will likely benefit from cutting out carbohydrates during treatment as well as from fasting and choosing a ketogenic diet. 

Not all insurance plans will pay for a PET scan if other imaging, such as CT, shows no evidence of tumor spread, or metastasis. In that case, the cost out of pocket can be several thousand dollars. It’s an argument worth having with your insurance company and a procedure worth paying for if you have to. PET scanning after a non metastatic tumor is completely removed is useless; you will not be able to tell if it loves glucose. Why this matters is the topic of the next paragraph.

When the surgeon says, “I got it all,” it just means all the visible parts of the cancer were removed.

It’s become clear over the past decade that cancer spreads earlier than we’d ever dreamed, long before a tumor is large enough to be palpated or show up on scans. That means surgery may not cure you, even if the surgeon “got it all.” Even if the primary tumor was removed with “clear” margins, cancer cells may be lurking in distant places in your body. So if the oncologist says you need further treatment to kill any lingering and not yet visible cancer deposits, try to listen with an open mind—and keep going with your own anti-cancer regimen. 

Don’t count on going vegan or alkaline to cure cancer. 

Going vegan or alkalinizing your body may help, but once a cancer is well established—if it’s big enough to be diagnosed, it’s well established—the effects of alkalinization, though real, are not dramatic. So don’t rely on alkalinization—or any diet—in lieu of other treatment. No need to spend a lot of money on alkaline water, either. All that was needed to show benefit in laboratory animals with cancer was a little Arm & Hammer baking soda added to ordinary drinking water. 

Fast each night for 13 hours. 

A study of women with breast cancer found that this simple maneuver cut the risk of recurrence by a third. That statistic beats any superfood, medicinal mushrooms, supplements, and most chemotherapy regimens. This is so easy for most people, it’s almost a freebie. No food after dinner. Wait 13 hours or more (not 12!) before ingesting calories the next day. Water or black coffee or tea is fine.

Consider fasting before chemo, and afterward too, for a total of at least 48 hours.

Animal studies are clear: Fasting alone can slow cancer growth, and so can chemotherapy alone. But slower growth is still growth. When laboratory research animals (usually specially bred mice) are engrafted with fatal human cancers and treated either with fasting or with chemotherapy, they may get a little better at first, but all eventually die of their tumors. In contrast, animals treated with a combination of fasting and chemotherapy do much better long term. In fact, half of them are cured of the previously “fatal” cancer. 

New research shows that for humans, fasting during chemotherapy is safe, and seems to reduce side effects such as immune suppression and nausea. Studies are under way to confirm the survival-enhancing effects of combining fasting with anticancer drugs. 

Go ketogenic between chemo treatments.

You can get the fat-burning effect of fasting by going ketogenic, which means eating mainly fats, cutting way back on protein, and eschewing almost all carbohydrates, including “healthy” ones like fruit. In cancer, the ketogenic diet probably works best if calories are cut, as well. Luckily, the ketogenic diet is so satiating, most people eating this way consume fewer calories without thinking about it.

Most people pondering a ketogenic diet jump to the conclusion that you need to eat meat. You don’t. Eating fat is what’s needed to burn fat, not eating protein. Your body breaks down any fat it wants to use for energy into small molecules called ketones.

If you are successfully burning fat, ketones can be measured in your blood. Doing the ketogenic diet right requires that you check your blood ketone level daily, at home, by pricking your finger and measuring your blood ketone level with a ketone meter. These meters cost under $50 and are easily available online. If your blood ketone levels are high, hurray—you’re in ketosis; you’re succeeding. If you’re not checking your blood ketone level, you’re not serious about the ketogenic diet and you’re wasting everyone’s time, including yours. 

Urine ketone test strips don’t give a number, and worse, urine ketone levels lag behind blood levels by up to eight hours. Not nearly good enough feedback to bet your life on.

The ketogenic diet sounds hard, and it is, at first. You’ll need two things to succeed with it: a supportive household and a ketogenic diet coach, a doctor or nutritionist who has gotten lots of people into ketosis and kept them there. After two to four weeks of coaching, you’ll be flying through the ketogenic diet. There are plenty of online and in-person support groups to help you, too.

Go keto for radiation.

Animal studies show that fasting increases the anticancer effectiveness of radiation and decreases the side effects, just as it does with chemotherapy. But because radiation treatments are usually given Monday through Friday for five or six weeks or more, fasting isn’t practical. So go ketogenic instead.

Fast before cancer surgery. 

If you have to undergo surgery for cancer, cut back on calories in the weeks beforehand, and consider fasting in the day or two immediately before the operation. Animal studies suggest that this maneuver protects against various types of damage that can occur during surgery, including the often-overlooked neurologic damage from anesthesia. 

Rather than going it alone, employ a physician versed in the scientific literature on fasting. She can keep you safe during fasting, and may also go to bat for you when it comes time to explain your actions to your surgeon. 

The best treatment for cancer cachexia (weight loss) is the ketogenic diet.

One side effect of the ketogenic diet can be weight loss. For many of us, this is welcome. But two-thirds of patients with advanced cancers will lose frightening amounts of lean tissue and will typically be told to eat more calories—from anywhere. Many patients are advised to eat cookies and pizza and preprepared nutritional shakes packed with calories from carbohydrates.

The problem is that these additional calories can actually worsen cancer cachexia. That’s because cancer cachexia isn’t caused by lack of calories, but by inflammation engendered in various ways by the presence of the cancer. 

 The ketogenic diet helps calm this inflammation. This allows preservation of lean tissue, and the resultant strength to pursue anticancer therapy. Once the cancer is successfully treated, the cancer cachexia will abate. Physicians versed in treating cancer cachexia may add omega-3 fatty acids concentrated from fish oil, anabolic steroids, and anti-inflammatory drugs such as ibuprofen to the ketogenic diet.

Expect your friends, family, and doctors to balk at your choices.

If you fast or go on a ketogenic diet, you’re on solid footing, health-wise. But your people won’t like it—especially if you’re thin and suffering from cachexia. Our first instinct when helping the sick is to bring food.

Food is, of course, deeply connected to our ideas of self. We even define our spirituality by what we eat. Jew, Christian, Muslim, Buddhist, spiritual-but-not-religious—what separates us as much as the way we apprehend reality is our menu.

What most of us have forgotten is that fasting is an ancient practice for purification and preparation for spiritual leadership across most traditions. In the Hebrew bible Moses fasts for 40 days while inscribing the stone tablets. This teaching is echoed in the Christian bible, in Jesus’ 40 days of fasting before setting out on his mission. There is the monthlong fast of Ramadan in Islam. The Buddha reportedly fasted immediately before attaining enlightenment, and Native Americans fast during vision quests and sun dances.

Religious fasts sometimes prohibit water as well as food. I don’t recommend going without water. In this article, fasting refers to water fasting, the taking of water and other noncaloric beverages such as unsweetened tea or coffee.

In humans, fasting is still investigational in terms of cancer recovery, but the few studies published show that overall, short fasts of up to several days are safe for people with cancer. So if your chosen recovery program includes short fasts, go about your business with confidence, knowing that you are in exalted company. 

Women who do several hours a week of both aerobic and resistance training during chemotherapy not only feel a whole lot better than those who rest; their cancer is also less likely to return.

During chemotherapy, exercise.

Studies show that during chemo, mild exercise is good—but vigorous exercise is better. Women who do several hours a week of both aerobic and resistance training during chemotherapy not only feel a whole lot better than those who rest; their cancer is also less likely to return. 

After chemotherapy, exercise.

Once treatment is finished, keep going. Exercise is great for reducing the risk of cancer recurrence. 

If you like coffee, drink it. 

Studies suggest that coffee prevents cancer recurrence. If you don’t like coffee, no need to start drinking it. But don’t tell others it’s unhealthy.

The evidence for most supplements and botanicals is weak. 

These are typically tested on “cell lines.” One of the most popular cell lines, MCF-7, was extracted in 1970 from fluid surrounding the lung of a 69-year-old nun dying of breast cancer. The nun’s name was Frances Mallon, and though she died long ago, her breast cancer cells have been expanding indefinitely in liquid culture bottles in laboratories around the world, where they are used to test breast cancer treatments. Many of these treatment hopefuls are botanicals, and many of them do kill some of Frances Mallon’s 50-year-old breast cancer cells. The conclusion of many such studies is that “substance X successfully treats estrogen-receptor-positive breast cancer.”

Well, if you’re a test tube with the exact version of estrogen-receptor-positive breast cancer that afflicted Frances Mallon decades ago, that’s great news. If you’re not, take the announcement with a grain of salt. Most test tube studies of supplements and botanicals as breast cancer treatments use one of only three cell lines: MCF-1, MDA-MB-231, and T-47D. That’s not much to go on.

Understand why some people have to tell you how to treat your cancer.

Learning that you have cancer frightens people. Feeling that “The Answer” is out there can be comforting. For some people, telling themselves that they must have done something—sinned, if you will, either on purpose or by accident—can be comforting too. Like religious fanatics who proselytize with fervent assuredness, those promulgating a sure cure for cancer are mainly looking to comfort themselves. 

Emotions run high. You may lose friends over your treatment choices. With true friends, the loss will be temporary. 

What to make of unusual recoveries.

If you have a friend who has recovered unexpectedly from a terminal diagnosis, help them celebrate. Urge their treating oncologist to publish the case in a peer-reviewed medical journal. That way others can benefit from the detailed knowledge that can be extracted from your friend’s experience. But if you must travel through cancer, your path must be your own. 

How to know if you have the right oncologist.

Your “right” oncologist may be warm, personable, and affectionate—or not. Still, you should feel relaxed in his presence, as though he’s on your side. If you find yourself hiding your supplement use or special diet from your oncologist, ask yourself if it’s because you feel subtly chastised when you bring those things into the conversation. If the answer is yes, find a new oncologist. The doctor-patient relationship isn’t trivial. It’s part of the treatment. Remember: Your cancer is unique, so consult your oncologist before using the advice in this article. 

One last thing.

Patients often confide that they feel ashamed by having cancer, as if it’s a personal failing. When I hear this, I want to weep. Over the years, what I’ve learned is how little I know—or anyone else knows—about life in general, and about the particular part of life we call cancer. But I do know this: Cancer is ubiquitous throughout nature; it is a personal tragedy; and, most important, it is no one’s fault.

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