Red Meat Consumption Linked To Colorectal Cancer
Colorectal cancer, or cancer of the rectum and large intestine (colon), is a
major public health problem in every corner of the developed world. Roughly
speaking, a diet containing less than 40 grams of animal
fat per day conveys
one-half the risk of colon cancer of a diet containing 65 grams or more per day.
Similarly, a diet containing 60 grams or less of red meat per day carries half
the risk of a diet containing 130 grams or more per day.
According to recent findings issued by the American Institute for Cancer
Research (AICR), consuming more than 18 ounces, or a little over a pound,
of red meat (pork, beef, lamb and goat) each week can significantly increase a
person's risks for developing colorectal cancer. In addition, every ounce and a
half of red meat a person eats over 18 ounces increases their risks by 15
Red meat contains substances linked to colon cancer. For example, some
studies suggest that the heme iron (the compound that gives red meat its color)
may increase the risk of developing colon cancer.
Furthermore, heavily cooked or well-done meat, in which the surface is browned
or blackened, contains substances called heterocyclic amines, which in a
laboratory setting have been found to cause cancer.
AICR recommends that two-thirds of a meal consist of
Consuming less red meat and more plant-based foods can significantly decrease a
person's risks of developing colorectal cancer.
Don't Eliminate Red Meat
These recommendations are not meant to encourage people to completely eliminate
red meat from their diet. Consuming red meat in modest amounts is a valuable
source of nutrients, including
Moderation is the key.
Try serving about three ounces (about the size of a deck of cards) of cooked red
meat at meals.
Avoid Processed Meats
AICR also recommends eating very little processed meat (meat preserved by
smoking, curing, salting or adding chemical preservatives), such as ham, bacon,
hot dogs, sausages, pastrami and salami. Every ounce and a half of processed
meat eaten a day is thought to increase a person's risks of developing
colorectal cancer by 21 percent.
Making better dietary choices
Experts have long believed that eating a diet rich in
fiber is good for
cancer prevention and good health in general. Aiming for a
healthy diet, try to
increase your fiber intake to 25 or 30 grams per day, emphasizing wheat bran. Of
course, this should be done gradually, since the digestive system needs a little
time to adjust to a drastic increase in fiber intake.
calcium intake can prevent both colorectal cancer and polyps.
One most compelling study found that people who were given regular calcium
supplements developed far fewer polyps and reducing polyp growth is
probably a good thing for your chances of later developing colorectal cancer.
The intimate interplay between
vitamin D and the body's calcium metabolism
certainly suggests that vitamin D could enhance the good effects of calcium.
Studies suggest that you can reduce your risk of colorectal cancer by 50 or
60% by increasing the amount of folate in your diet. Folate happens to be a very
important substance; it is a critical player in the synthesis of both DNA and
RNA, the genetic building blocks, as well as other areas of the human
metabolism. Therefore, in theory, it is not surprising that lack of folate in
the diet leads to serious problems. Since most experts agree that cancer is
caused by insufficiently repaired defects in our DNA, it makes sense that
inadequate amounts of folate might lead to DNA abnormalities and a greater risk
Some research has indicated that taking antioxidants, such as
vitamin C or carotenoids, may reduce cancer risk. A diet high in
antioxidants is usually also
high in vegetables. These kind of diets seem to be protective against colon
cancer, though we don't know exactly why or how.
Among all the antioxidants, selenium seems to be the only one that shows real
promise in the prevention of colorectal cancer. This is largely based on one
study that showed that taking a selenium supplement over a period of several
years led to a 25% decline in the incidence of colorectal cancers. People who
are concerned about preventing colorectal cancer can take 200 ug of selenium per
day. Remember that the safe upper limit of selenium is 400 ug/day.
To sum up, a diet high in fruits and vegetables (5+ servings/day,
emphasizing fresh vs. cooked items), high in whole grain fiber and low in red
meat and saturated fat is recommended. You can take a multivitamin each day
that provides an additional 400 ug of folate and sufficient vitamin D. Finally,
it would be reasonable to take a 1200 mg supplement of calcium, as well as a 200
ug supplement of selenium.