Cancer. We do our best to avoid talking or even thinking about being a victim. But if something else doesn’t get us first, all of us are likely to develop some form of the disease or, at a minimum, harbor a latent form. Is there anything we can do to stack the cards against this?
There is no question that certain forms of cancer are heritable. Whether children of parents with some cancers develop them also depends on a unique arrangement of the nucleotides, the constituents associated with specific genes involved in the disease’s development. In other words, the same genetic mutation has to be passed on, too.
Even for those who have been dealt a “genetic hand” with a significantly higher risk factor, recent studies show there are ways to reshuffle the deck, so to speak.
Researchers from various scientific and medical disciplines are demonstrating the importance of inflammation as causal in the development of a variety of conditions, including heart disease, neurodegenerative diseases such as Alzheimer’s, type II diabetes, peripheral artery disease and colon, liver and prostate cancer.
Scientific, clinical and epidemiological studies suggest that many diseases are also associated with certain lifestyles and, in particular, the types of foods commonly consumed by a population.
These observations recently led a group of investigators to more closely examine the connection between the foods we eat, inflammation and the development of disease, specifically prostate cancer. Their results present strong evidence that links an anti-inflammatory nutritional component with reduced risk. (See this issue’s “Research Update.”)
But what, exactly, is inflammation and why does the body have this mechanism if it contributes to disease? Here’s the short answer:
The cells of the immune system are called into action at a site the body believes is under attack by a “bad guy,” a pathogen such as a virus, bacteria or aberrant cell like a cancer cell. Pathogen-fighting immune cells (macrophages) migrate to the compromised tissue and immediately activate biochemical pathways that produce inflammatory molecules and proteins.
Some of these molecules function as messengers to attract other types of immune cells (neutrophils, mast cells) to the tissue under attack. The defending immune cells start producing a number of toxic substances (hydrogen peroxide, free radicals, superoxide radicals), supposedly directed at the pathogen.
As with any “weapon of mass destruction,” not only are the pathogens negatively affected by the toxins, but there is also significant “collateral damage” to normal cells. This constitutes what is referred to as inflammation: swelling, damage to cells including their genetic material (DNA) and an increase in blood vessel permeability, with subsequent leaking of fluids into the area.
When the inflammation occurs on an exposed part of the body, such as the skin, it appears swollen and red and is often painful. As we age, the inflammatory response becomes even less targeted, accounting for a higher, age-associated incidence of tissue inflammation.
Now back to the study mentioned earlier and its answer to how it may be possible to avert one of the diseases associated with an over-exuberant immune system reaction and resulting inflammation.
Prostate cancer accounts for about 30% of cancers in the U.S. The researchers examined the relationship between the incidence of this disease in people and their consumption of the omega 3 fatty acids present in fish. Subjects who had the highest plasma levels of the omega 3s had the lowest incidence of prostate cancer, compared to controls who consumed little or no omega 3-rich fish.
The researchers also found that those people with an inherited gene variation, which would normally make them more susceptible to aggressive prostate cancer, also responded to the omega 3 diet. There was a dramatic decrease in the incidence of cancer in these subjects and a significant inhibition of pre-existing cancer growth.
Not only did the research suggest that the omega 3s had a protective effect, but the study also identified its mechanism.
The previously mentioned gene, which confers prostate cancer susceptibility, codes for an enzyme, COX-2 (cyclooxygenase-2). COX-2 is involved in the synthesis of mediators of inflammation, the prostaglandins. It appears that the omega 3 fatty acids interfere with this enzyme, preventing it from converting omega 6 fatty acids to prostaglandins.
This study and others point to the need for a healthy 1:2 ratio of omega 3s to omega 6s in what we eat. The problem? The omega 6 fatty acids are found in many foods prepared with vegetable oil—bread, crackers, cakes, fried foods—that are favored in western diets. The solution may be as simple as substituting olive oil for vegetable oil, whenever possible, and including at least one fish meal per week in our diets.