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Is It Possible to Prevent Cancer?

No disease is as feared or misunderstood as cancer. Because of this fear and confusion, a diagnosis can shake us to our core. At which point, we’re especially vulnerable to bad advice from the medical establishment, as well as unproven and potentially harmful “alternative” modalities.

While there are many ways of treating cancer, and different cancers have radically different potential outcomes, the best policy is always – when possible – prevention. This article will compare the evidence for the mainstream prevention strategy – early detection – with the kinds of diet and lifestyle changes I promote.

You'll discover that you have a lot more control over your health destiny than we’ve been taught.

Mainstream Prevention: Early Detection and Screening

When you stop to think about it, early detection does not “prevent” cancer. Instead, in theory, it catches cancer early enough to do something about it.

So the question is, does population-wide screening of asymptomatic people help us “do something about it” in a way that reduces suffering, disability, and death. Turns out that with the exception of the pap smear for cervical cancer, screening actually may harm more people than it helps.

The Cochrane Collaboration, a non-profit health research group that does not receive funding from industry, has determined that mammography for early detection of breast cancer has the following risk/benefits profile:

If 2000 women receive biannual mammography for 10 years:

  • One woman will be saved from death by breast cancer.
  • 10 women will be treated for cancers they do not have or that would never have been detectable or become  significant (through partial or complete amputation of the breast and/or drug treatments).
  • 200 women will have a “false alarm” and experience, for a time, all psychological stresses of believing they have cancer when in fact they are perfectly fine.
  • 2000 women will undergo painful mammograms with these radiation screenings increase the risk of lung  cancer and heart disease.

For more information on the science behind these statements, check out Gilbert Welch’s book, Overdiagnosed.

The risk/benefits profiles for population-based PSA testing for prostate cancer and colonoscopies for colorectal cancer are similar. They harm more people than they help, and turn hundreds of thousands of perfectly healthy people into worried patients. (For more information, see The Great Prostate Hoax, by Richard Ablin with Ronald Piana.)

So if we can’t “prevent” cancer through screening, what can we do? Are we powerless to change our fate, or do we just have to wait until we get sick enough to need treatment? And at that point, isn’t it often too late?

To answer that question, we have to look directly at cancer and its causes.

What Causes Cancer?

Cancer is a condition in which normal cells mutate and proliferate without limits. Everyone “knows” that the initial trigger is genetic mutation in those cells. Therefore, the thinking goes, cancer must be a genetic disease – a combination of genetic predisposition and environmental damage.

For now, I’ll leave out the part of the story where cancer is a metabolic disease – in which cells switch from aerobic to anaerobic respiration even in the presence of sufficient oxygen, with genetic mutation following and not causing the damage – and focus on the relative contributions of our genes, the toxins in our environment, and food.

We know that in most cancers, genes play a very minor role. It’s been estimated that only about 3% of all cancers are 100% genetically determined (that is, the person was going to develop that cancer no matter what they might do to try to prevent it). May cancers are genetically predisposed, but can be prevented or mitigated through lifestyle. And some cancers are entirely the result of diet and lifestyle choices.

If cancers were mostly genetic, then identical twins would experience the same fates since their genes are identical, right? Yet a 2004 review of identical twin studies found that if one twin has cancer, there’s, on average, less than a 20% chance of the other twin developing it.

And since most identical twins share common diets and lifestyles in childhood (and often beyond), that 20% concordance actually represents a huge inflation of the role of genetics alone.

The Toxins in Our Environment

When people think of reducing the causes of cancer, one of the factors they think about is lowering exposure to environmental toxins. After all, the atomic bombs and the story of Marie Curie seems to prove that radiation causes cancer, and we hear stories in the news all the time about cancer clusters in places that have toxic waste dumps and polluted air and water.

The problem is, most of the substances that are supposed to cause cancer in humans have never been proven to cause cancer in humans. They are on the list of “suspected” or “known” carcinogens because they have been shown to cause cancer in laboratory rats or mice. Since about half of the substances that cause cancer in mice don’t cause cancer in rats, and vice versa, it’s a huge leap to assume that they will have a known effect in humans. Also, the doses given to the rodents are orders of magnitude higher than those humans consume.

To be clear, I’m not in favor of environmental toxins. I believe we should live on a clean, healthy planet. But the evidence suggests that the carcinogenic effect of most toxins and radiation in our environment can be overcome through diet and lifestyle changes that are within our power to make. (For more information, see Whole: Rethinking the Science of Nutrition, by T. Colin Campbell, with Howard Jacobson, especially chapter 7.)

The real problem with focusing on environmental toxins is that it misdirects us from what is by far the largest contributor to our cancer destiny: the food we eat every day.

The Best Odds Anti-Cancer Diet

We can prevent up to 90% of all cancers by consuming an anti-cancer diet. We are not helpless in the face of our genetic inheritance and our toxic environment. We can control the lion’s share of our risk through our daily choices.

And we don’t need to spend our entire paycheck on exotic anti-cancer superfoods, or spend our days preparing $200 smoothies full of brain dust and moon juice.

Instead, we can eat the way long-lived people around the world eat: lots of fruits, vegetables, legumes, and whole grains; smaller amounts of nuts and seeds; small portions or occasional amounts of animal foods; and little to no highly processed foods.

When we look at populations around the world, there are clear and dramatic correlations between diet and cancer incidence and mortality. In rural China, some areas had 300+ times the risk of certain cancers than others. Prostate cancer was virtually unknown in Japan before they adopted a Western diet high in animal foods. Colorectal cancer was unheard of in sub-Saharan Africa among native populations eating a plant-based diet. (For more information, read The China Study, by T. Colin Campbell and Thomas M. Campbell, and Proteinaholic, by Garth Davis, MD, and Howard Jacobson.)

It’s time that the medical profession and various cancer charities acknowledge and publicize the empowering truth: that we can prevent most cancers with our forks and knives.

Starting soon, Wholistic Health Studio of Durham will be hosting me to teach a series of classes on Preventing Cancer. Click here for additional information or to register.

TeleCoaching on How to Transition to a Plant Powered Diet

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