Can eating the right foods help to prevent or treat cancer?
If there’s two things we love around here, it’s Food and Science. Normally we’re happy to let them stand mostly on their own, enjoying a nice salad or an article on neuromuscular activation pretty equally. But today we’re going to merge these two and talk about the science behind Angiogenesis and how your diet can effect your body’s ability to fight not just fat gain, but also cancer.
What is Angiogenesis?
Angiogenesis is a process in the body that grows new capillary blood vessels. It occurs in response to injury, growing vessels around the injury site to help repair the damaged tissue, as well as during development of the human body as we grow. It’s a natural process regulated by a precise balance of bodily functions, some to stimulate growth and others to inhibit it. The key to healthy angiogenesis is the balance between growth and maintaining homeostasis (the body’s optimal conditions). Angiogenesis continues throughout our lives, and seems to have a physiological “set point” where we naturally like to rest (more on that later).
When the angiogenic balance is upset, capillary vessels will either form where they shouldn’t or fail to form where they should, with the most common cause of disease being excess growth in different parts of the body. Depending on where this occurs, angiogenic imbalance can play a major role in development of many diseases. Two primes examples of this are age-related “Wet Blindness”, where excess angiogenesis promotes the leaking of blood into the retina, and various Cancers, where excess angiogenesis turns an otherwise benign growth into a health hazard.
Angiogenesis in Cancer
We mentioned above that angiogenic disorders can lead to cancer; lets talk about that a bit more. First, though, we need to define a few words that get tossed around a lot, but aren’t always explained:
Tumor: a common term for a “neoplasm” or a “new growth” which is different from the cells around it. This can literally mean any growth of cells which doesn’t look like whatever cells are sitting next to it. A skin mole is technically a tumor; they aren’t inherently dangerous.
Benign, Carcinoma in Situ, & Malignant: A neoplasm is Benign if it develops and poses no health risk (like a skin mole), Carcinoma in Situ if it may potentially develop into cancer but doesn’t invade other tissues, or Malignant if it develops into cancer and spreads.
Metastases: new formations of the same cancer somewhere other than it’s origin. For example, if a cancer forms in the breasts and travels (“metastasizes”) to the lungs, it is called “metastatic breast cancer” and not “lung cancer”. Some cancers rarely metastasize, others do so aggressively.
It’s important to note that everyone develops tumors at some point, and most people never even know it. The vast majority of neoplasmic growths never get bigger than a few millimeters in size (about the size of a couple large grains of sand). In order to grow, they need a blood supply. This is where angiogenesis comes in. Some tumor cells have the ability to either stimulate excess angiogenesis on their own, or induce cells near them to induce angiogenesis. Whether the neoplasm does the dirty work or has an accomplice do it, the results are the same: new capillary vessels form and start feeding the tumor nutrients and oxygen. If this keeps up, the tumor will grow and may metastasize to other areas of the body.
What is Antiangiogenic Therapy?
I’m going to give you the good news in this section first: this is talking about Antiangiogenic Therapy using drugs that modify the Homeostatic Angiogenesis in your body. This means that the cited benefits and side effects are caused because the drugs exceed the natural highs and lows of the human body, which is something your body cannot normally do on it’s own. Keep this in mind when you read the following section about healthy eating to control angiogenesis.
There is a strong causal link between angiogenesis, and the development and spread of malignant cancers. New treatments have been, and continue to be, developed that treat cancer from a novel approach: instead of trying to kill the cancer with things like chemotherapy, why not starve the cancer by turning off it’s source of food? Antiangiogenic drugs are currently on the market which do just this and several are approved by the FDA to treat different cancers. Some examples include Bevacizumab (for glioblastoma, metastatic colorectal cancer, some non-small cell lung cancers, and metastatic renal cell cancer), and Sorafenib (for hepatocellular carcinoma and kidney cancer).
Originally there were few expected side-effects of antiangiogenic therapies, but recent studies that looked at usage of these drugs more long term have noted this to be unfortunately untrue. Side effects may include problems with bleeding, clots in the arteries (resulting in stroke or heart attack), hypertension, and protein in the urine. Issues with natural processes such as wound healing, heart function, etc. can also occur. These aren’t terribly pleasant, but it should be noted that the side effects of the drugs are carefully weighed against the potential harm of the cancer, so the hypertension may not be as serious as the kidney cancer in the long run.
How Can You Eat to Promote Healthy Angiogenesis?
So, remember how we gave you the good news first in that last section? Good, but here’s a reminder: Pharmaceutical Drugs act very differently on the human body than anything you would normally put in your body. The side effects of the drugs we talked about before do not apply in this section, so don’t worry!
Studies have shown that including certain foods in your diet can promote a healthy amount of angiogenesis, curtailing the excess seen in the root cause of many diseases. This means that you are less likely to develop diseases like cancer or wet blindness if you eat a diet with antiangiogenic foods. Have a look at the following chart, presented during a TED Talk by Dr. William Li, a noted researcher in angiogenic therapies. He compared the antiangiogenic effects of various foods as compared to drugs specifically designed for that purpose:
This chart is comparing the effect each substance (cancer drug, common drug, or dietary factor) has on Angiogenesis in general. I won’t lie, I’m not a big fan of the axis labels, which don’t provide a decent enough level of detail to make this a one-stop infographic, BUT it is useful in comparing the relative effects of each thing on controlling homeostatic angiogenesis. Basically, the thing with the most importance is the presence of blood vessels, which regulates whether or not the body attempts to make more. Working down the list, we see that many common foods are almost as important, including Vitamin E, Green Tea, and Citrus fruits.
The kicker is that a lot of these foods are otherwise really good for you and tasty! Here are some examples from various food groups:
- Berries (Strawberries, Blackberries, Raspberries, Blueberries)
Veggies and Plants:
- Olive Oil
- Green tea
- Red Wine
- Dark Chocolate
You might be saying, “but how much do I eat?” That’s a fair question, but it doesn’t have a set answer. The goal is to add these to your diet in healthy amounts, just like you would any other food. Overeating fruit can cause sugar overload, just like overeating tuna can cause you to take in too much trace mercury. It’s all about being smart. Replace some of your weekly food intakes with the options above, maybe switching out a banana for an orange, have tomato on a salad, or use nutmeg when you cook. As long as you aren’t going to excess, you’ll get the angiogenic regulation without messing up your diet. Be especially careful with the red win and dark chocolate; they taste great but they carry a lot of calories!
And as always when we’re super science heavy. Sources:
1. The Angiogenesis Foundation. http://www.angio.org/
2. “Angiogenesis”. Wikipedia. http://en.wikipedia.org/wiki/Angiogenesis
3. AngioWorld. http://www.angioworld.com
4. “Angiogenesis Inhibitors”. NIH National Cancer Institute. http://www.cancer.gov/cancertopics/factsheet/Therapy/angiogenesis-inhibitors