Tell Me What to Eat to Help Prevent Colon Cancer: Nutrition You Can Live With

Introduction

I'm turning 39 in a month and let me tell you, after researching and writing this book, I'm volunteering for a colonoscopy by my 40th birthday. I'm going to have one done at 50, 60, and hopefully, I'll be around to have it repeated at 70 too. It's about a two-day time investment and from what I've heard, the day before the procedure is the worst. The day is apparently split between drinking a horrible tasting solution and running to the bathroom. According to my experienced friends, it's all down hill from there.

After this two-day ordeal you are well screened for colon cancer, any polyps found have been removed, and the procedure is good for 10 years. I don't know about you, but I feel this is one of the best medical deals going. If there were something similar for ovarian cancer I'd be signing up for that too.

Here's why you should care...

Colon cancer is the second deadliest cancer in the United States.

The American Cancer Society estimates there are over 130,000 new cases of colorectal cancer each year, with about 55,000 deaths from it each year.

If you don't smoke, and your breast or prostate stay cancer-free, the biggest cancer risks are your colon and rectum.

The good news

Nine of 10 deaths associated with colon cancer can be avoided. The key is finding and removing pre-malignant polyp growths called adenomas (they usually take a decade to become cancerous growths). The American Institute of Cancer Research estimates that as many as 75 percent of colon cancer cases are preventable by diet.

There are three steps to preventing colon cancer:

Screening.

Minimizing exposure to carcinogens.

Maximizing exposure to substances that help protect the body against these carcinogens.

A healthy diet is a large part of what Chapters 2 and 3 (as well as the rest of this book) are all about. You will read about the common screening tests for colon cancer and how to minimize exposure to carcinogens in Chapter 1.

The thought of any type of cancer is very real and very scary for most of us. This book is about turning that fear into something positive and productive. I personally feel better if I keep current with all my different screenings, and if I take commonsense steps with diet and lifestyle to reduce my risk of cancer. Beyond that, it's out of my hands.

Chapter 1

Everything You Ever Wanted to Ask Your Doctor About Colon Cancer

What exactly is a colon and what's this word I keep hearing...colorectal?

First, let me explain what the large intestine is and what it does. Then you'll understand what the colon is. After food travels through the stomach and small intestine (where food is digested and calories and nutrients are absorbed), any material left over passes into the large intestine, which has two parts—the colon and the rectum. The colon is the upper five or six feet of the large intestine and rectum is the lower five or six inches (the part that reaches the anus, where waste exits the body).

Because the tissues and cancer tumors that appear in the colon and rectum are so similar, the names for cancers of the colon and rectum are often combined as colorectal cancer.

What is colon cancer?

Colon cancer is when cells in the colon grow out of control, forming a small group of abnormal cells. These cells grow into a lump called a polyp, which is a small, non-cancerous tumor that may turn into cancer.

What causes colon cancer?

Unfortunately we do not yet know the exact causes of colon cancer. What we do know is that both inherited and environmental factors may lead to colon cancer.

One proposed hypothesis is that bile acids promote the development of colon cancer, so scientists have been looking to foods and medications (such as hormone therapy) that reduce the production of these bile acids.

How does it spread to other organs in the body?

You might hear the word metastasis or metastasized in reference to colon cancer. Metastasis is when cancer cells have spread to other parts of the body. How does this happen? First the colorectal tumors develop inside the colon or rectum. Then, after a certain point in the life of the tumor, some of the cells break away from the tumor and enter the bloodstream or lymph system, possibly forming new tumors in other parts of the body.

What's a polyp, and why are they important?

Most colorectal cancers begin as non-cancerous overgrowths of cells called polyps. You might also come across the more medical term adenomatous polyps and the definition: visible protrusions that develop on the mucosal surface of the colon or rectum.

Polyps can bleed or interfere with the large intestine's doing its job. Most can be removed. But they may become cancerous if they aren't removed in time.

Polyps are found in the colons of about 30 percent of people by age 50. By age 70, the number jumps to 50 percent. However, less than 1 percent of these lesions ever become cancerous. Experts estimate that it takes an average of 10 years for a polyp to become malignant (cancerous). Experts don't know why some polyps eventually become cancerous, but think it may have to do with genetic changes in colon cells over long periods of time.

When the doctors look at a polyp they consider its size, the organization of the cells within it, and the look of the cells themselves. Flat, long, or stalk-shaped cells may be cancerous.

Who's at risk?

Age: Anyone at any age can get colon cancer. People age 50 and older are most likely to get this disease. Why? Because as we age, our cells don't repair themselves as well, and genetic changes within the colon tissue predispose cells to grow out of normal control.

Gender: Both men and women get colon cancer, but men are slightly more likely to develop colorectal cancer. They are also more likely to die from it.

Ethnicity: In the United States, rates are higher among African-Americans, Japanese-Americans, and non-Hispanic whites than among other ethnic groups.

Worldwide: Colorectal cancer rates are highest in North America, northern and western Europe, and Australia, and are lowest in Asia and Africa. One of the biggest clues that diet and lifestyle are related to colon cancer risk comes from looking at immigrants. People who come from a country with a low incidence of colon cancer (like Japan), to a country with a higher incidence of colon cancer (like the U.S.), end up mimicking these higher cancer rates within the first and second generations. If colon cancer were entirely genetic, then we wouldn't see a shift in the risk.

People who have any of the following are considered to be at higher risk for colon cancer:

A parent, sibling, or child with colon cancer or polyps has two to four times the risk (according to studies by Columbia University and Memorial Sloan-Kettering).

A family history of breast, ovarian, uterine, stomach or liver cancer also may increase your likelihood, but exactly how much is not yet known.

A personal history of polyps can triple your risk.

Your risk of getting this cancer also increases by 30 percent if you've had chronic inflammatory conditions, such as ulcerative colitis or Crohn's disease, for eight years or more.

According to the Harvard Health Letter, people with at least one first-degree relative (mother, father, child, or sibling) who has had colorectal and ovarian or endometrial cancers probably have a genetic predisposition to the disease. They should undergo screening at a younger age and possibly more frequently than the general population (Nov. 1, 1998 vol. 24).

People who smoke or are sedentary (having a low physical activity level) have a higher risk for colorectal cancer. For information on the food and diet related risk factors for colorectal cancer, see Chapter 3.

Adults who do not have genetic or other specific symptoms or factors putting them at high risk, are automatically considered at average risk for colon cancer when they reach age 50. The chance of an average-risk patient developing invasive colorectal cancer is one in 19.

What percentage of colon cancer can be attributed to heredity/genetics?

This answer depends on whom you ask. Of the 130,000 cases of colon cancer diagnosed each year, 50 to 85 percent have no major genetic component, according to Johns Hopkins University researcher Steven Laken. Other researchers estimate that 5 to 10 percent of all colon cancer is considered hereditary. I find this interesting because about the same percentage of breast cancer is genetically related.

What can I do if I have colon cancer in my family?

There are many things you can do to find out if you have a genetic predisposition to colon cancer. In the past few years, genetic tests have become available for two forms of inherited colorectal cancer:

Familial Adenomatous Polyposis (FAP), a rare type of colon cancer that strikes people under the age of 40. This test is now commercially available.

Hereditary NonPolyposis Colorectal Cancer (HNPCC, also called Lynch syndrome), the most common inherited form, often diagnosed by age 45 or 50. Families with this type of colon cancer also usually have family members with ovarian, endometrial, or other cancers. This test is, at the time of publication, still considered experimental and offered only through certain research institutions.

Note: Genetic screening for FAP or HNPCC should only be done along with genetic counseling and the tests only indicate whether someone has a higher than average risk of getting the disease.

The bottom line is that you have to get yourself in for screening early enough and then keep up the schedule (every 10 years for a colonoscopy). If you have a genetic tendency to colon cancer you should still follow the lifestyle and diet suggestions to help prevent colon cancer. These steps may postpone the development of colon cancer.

What are the signs and symptoms of colon cancer I should be looking for?

The early stages of colon cancer are usually without symptoms. The following are warning signs of an intestinal tumor, but can also be caused by other factors—from the flu to stress. If any of the following symptoms persist, it's important to see a doctor immediately to determine the cause.

A prolonged change in bowel habits (diarrhea or constipation).

A constant feeling of having to go to the bathroom (or a feeling that the bowel hasn't emptied completely).

Rectal bleeding or blood in the stool (either bright red or very dark in color).

Stomach discomfort (cramps, bloating, or fullness).

Frequent gas pains.

Decreased appetite and/or weight loss with no known reason.

Abnormal weakness and fatigue.

Stools that are narrower than usual.

Vomiting.

Unexplained anemia (low levels of iron in the blood).

Jaundice (yellow-green discoloration of the skin and white part of the eyes).

These symptoms may be caused by colorectal cancer or by other conditions. It is important to check with your doctor.

Should I be screened for colon cancer? At what age?

Yes, and it depends. Stating the obvious, the earlier you catch colon cancer, the better. A recent expert panel (appointed by the Agency for Health Care Policy and Research) determined about 18,000 more lives could be saved each year if more people were simply screened by the age of 50.

Routine screening helps to detect cancer tumors in their earliest, most treatable stages. This can be very effective. If the cancer is detected early, 90 percent of the cases can be cured. Unfortunately, only 40 percent of colon cancer cases are caught early. According to the Harvard Health Letter, once the cancer spreads to the lymph nodes, the five-year survival rate drops to 50 percent. If the disease has spread to the liver, the survival rate plummets to less than 3 percent (Nov. 1, 1998 vol. 24).

Here are some of the screening options available:

Fecal Occult Blood Testing (FOBT)

These laboratory kits cost about $8 and they are the most common