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Can We Prevent Cancer?

Jonathan Vellinga, MD -

Can We Prevent Cancer?

Celebrating a win in the battle against cancer gives us hope. After a lengthy, grueling battle, you, your friend, or a family member has heard the sweet music of a doctor saying, “It’s in remission!” With a nearly 70% estimated 5-year survival rate for all cancers combined (1), you likely know someone who has tangled with cancer and won!

Unfortunately, cancer is still very prevalent, as it is estimated that nearly 40% of people in the US will be diagnosed with some form of cancer in their lifetimes according to the National Cancer Institute (1). That’s a sobering statistic.

What if you could avoid that whole battle? What could you do to reduce your odds of getting cancer? Fortunately, there are many strategies to strengthen your health and place yourself in a lower-risk category. The more of these life-fortifying prevention strategies you can implement in your life, the more you stack the odds in favor of preventing cancer. By the way, stacking the odds in your favor isn’t so difficult. The strategies chosen below were specifically picked due to their ability to get a lot of return for a little effort.

What is Cancer?

Normal cells have a birth and death lifecycle. Old cells die, and new cells are created to replace them. Cancerous cells are marked by runaway cell creation which damages tissues and may travel to other parts of the body to do the same (2). Quickly growing cells in a specific spot can create a dense group called a tumor, which can then release cells that invade other parts of the body. When a tumor invades other areas besides the primary site, it is known as “metastasis.” When cancer metastasizes to organs, bones, or blood, it can interfere greatly with normal functioning, producing symptoms that, for many, can be the first indication of a problem.

The Angiogenesis Connection

Not only do cancerous cells reproduce in an out-of-control manner and create tumors, but they also develop and strengthen circulatory vessels such as capillaries to ensure a constant energy supply. This building up of a blood supply is called “angiogenesis.” Note that other processes use angiogenesis, but cancer must create new blood supplies. With all the additional cells it is producing, it needs the extra energy delivered to it by a bigger blood supply. In fact, an ever-increasing capillary supply in one small region of the body can serve as a red flag that cancer is present.

Shutting Down the Transportation System

Cancer’s primary form of fuel is glucose, a form of sugar derived from foods or made in the liver that travels in the blood to reach every part of the body. That makes it tricky to starve cancer because glucose is a major fuel for the body and appears to be the preferred fuel source for the brain.

Rather than starving cancer (and your brain) of the glucose that the blood is carrying, there is a way of shutting off the formation of capillaries that make up the blood supply to the cancerous region. This is called “anti-angiogenesis.” Scientists have discovered that some substances can cause withering of the capillary supply to cancerous cells. Without its constant supply of glucose from the blood in the capillaries, the abnormal cells can’t reproduce as quickly. Since the discovery of this mechanism for countering the growth of cancer cells, many foods and even cancer treatments have been identified as having this anti-angiogenic property. Anti-angiogenic substances continue to be a compelling research topic to this day.

Fostering vs. Inhibiting Cancer

One way to approach cancer prevention at a high level is to ask, “What kinds of things foster the growth of cancer?” Or, conversely, “what kind of things inhibits the growth of cancer?”

The strategy for reducing cancer risk then becomes one of pulling the welcome mat away: reducing things that welcome cancer growth while increasing things that deter cancer growth. Various studies indicate that chronically low vitamin D3, consistently high blood sugar, and obesity are correlated with higher cancer risk. Obesity on its own is associated with 13 different types of cancer according to the CDC (3). Fortunately, there are some very simple but powerful strategies for lowering the risk of cancer.

Ways to Counter Cancer Risk Through Nutrition

Increase Vitamin D3

Vitamin D3, also known as the “sunshine vitamin,” can act as a hormone, positively influencing many systems in the body including the immune system, cardiovascular system, and endocrine system. Almost every cell and tissue in the body needs vitamin D3, which can be supplied through food, supplements, and sunshine on the skin. Because of the many beneficial effects on the body, it has been researched in conjunction with many diseases and conditions. Researchers have found that adequate vitamin D3 levels can have a positive impact not only on decreased risk of cancer but also on depression and pain (4). Recently, researchers found more direct evidence that there is a reduction in risk for 15 different kinds of cancers when vitamin D3 presence is high in the blood (5).


We may test your serum 25(OH)D level, which is the amount of vitamin D3 in your blood, and determine a daily dosage that will correct any vitamin D3 deficiency. Be sure to get your D3 from a high-quality brand of supplements, as vitamin D3 supplements are fat-soluble and subject to being damaged by oxygen and heat.

People always ask about sunbathing, which is the natural way to obtain vitamin D3 from the interaction of the sun with the skin. If you are deeply deficient, it may be difficult to pull vitamin D3 levels up by mere sunbathing, and unwise to try. If you are only slightly deficient, you can try getting sun on 70% of your body (no sunscreen) for 15-20 minutes each day when the sun is directly overhead. Sunbathing is not ideal for everybody, and we will take your personal history and risk factors into consideration when creating your plan. It is wise to get re-tested periodically to assure your levels are adequate and not to supplement beyond what we recommend for your situation.

Replace cancer-feeding sugary foods with tumor-starving foods.

Controlling the level of glucose in the blood (“blood sugar”) by reducing sugar in the diet is an important part of reducing the risk of cancer. It is known that cancer needs an extraordinary amount of glucose, which can be provided by excess sugar in the diet. So, several studies have looked at diabetes in particular, which is a metabolic issue where there are consistently high blood glucose levels. In studying the relationship between diabetes to cancer, researchers Ohkuma, et. al. determined that diabetes increases the risk for all types of cancers in both women and men (6). Even if you’re not diabetic, excess sugar can be quite destructive to the body in many ways so having a lower-sugar diet can reduce the overall burden on the body and put you in a lower risk category for cancer.

While cutting down on sugar, you can replace those items with good-tasting foods that help cut off the blood flow to cancer tumors. What are these miraculous foods? Dr. William Li, a physician and scientist, introduced these foods in a famous Ted Talk slide presentation in 2010 called “Can We Eat to Starve Cancer?” The presentation slide of anti-angiogenic foods (foods that cut off the blood supply to cancerous cells) is still on the Ted Talk site. The list includes such foods as berries, green tea, garlic, olive oil, and tomatoes.


  • Replace sugary drinks with green tea. Sugary drinks are known to increase the risk of cancer (7), so cutting these out of your life will automatically put you in a lower risk category. Drinking green tea instead of sugary drinks will further reduce your cancer risk. Green tea has a multitude of benefits, including cutting off the blood supply to cancer (anti-angiogenic), combating arthritis and aging, and reducing inflammation (8). Be wary of bottled green tea in the grocery store because many of these have added sugar! It’s best to make your own, using organic green tea bags or loose leaves. Using filtered water can increase the benefits of this strategy.

  • Use more turmeric in cooking or drink “golden milk” made from turmeric tea. The active ingredient in turmeric, called “curcumin,” has been proven to have anti-cancer properties (9) and even appears to target cancer stem cells (10) which are believed to start and maintain tumor growths. There are many recipes for golden milk online. Choose a recipe with little or no sugar to maximize the health benefits. Alternatively, take a high-quality curcumin supplement daily from a reputable supplement company.