Colorectal cancer is one of the most preventable cancers, yet it remains the third most common cancer among US men and women.
The good news is that rates have declined 30 percent among people 50 years of age and older, however incidence and mortality among individuals under 50 are on the rise and expected to climb. Among 20-34 year olds, rates of colorectal cancer have increased 51% since 1994 and in the period from 2010-2030, colorectal cancer in this age group is expected to increase by 90 percent.
At the Early Age Colorectal Cancer Onset Summit last week, I was one of the speakers talking about the concerning increase in this cancer among adults in their 20s through 40s.
Among 20-34 year olds, rates of colorectal cancer have increased 51% since 1994 – and in the period from 2010-2030, colorectal cancer in this age group is expected to increase by 90%.
Alarmingly, cancers in the under 50 population are diagnosed at later stages (most often due to delays in diagnosis) and appear to be more aggressive tumor types, both of which have implications for prognosis and survival.
What’s unknown is the cause of young onset colorectal cancer.
For those who have had possible precancerous growths removed from their colon/rectum — common among adults — taking vitamin D and/or calcium supplements does not reduce the risk of developing further growths, finds a randomized study reported in the New England Journal Of Medicine. The multi-year trial adds to the evidence that supplements do not protect against colorectal cancers.
While there are many reasons to take supplements, AICR recommends not to rely on supplements for cancer protection.
The 2,259 people in this study all had colorectal abnormal growths, called adenomas or polyps. Some of these growths on the lining of the colon or rectum could eventually lead to colorectal cancer, which is why they are commonly removed.
Within four months of having the polyps removed, the participants (who were 45 to 75 years old) were placed into a group where he/she took a daily dietary supplement of vitamin D, calcium, both or neither. The study was blinded so neither the researchers nor participants knew what they were taking. And when they joined the study, everyone had normal levels of calcium or vitamin D. Continue reading
If you choose to eat red and processed meats, just how often do you bite into that bologna sandwich or hot dog? What type of pork and beef do you eat? Is it low fat? What brand?
These are the kinds of answers that studies need in order to better understand how processed meat increases the risk of cancer, says Amanda Cross, speaking at our research conference today.
Cross, a scientist at Imperial College London, noted that the research clearly shows even small amounts of processed meat — and high consumption of red meats — increase risk of colorectal cancer. A study by Cross also suggests that processed meat increases risk of lung cancer; while diets high in red meat risk increase risk for esophagus and liver cancers.
Historically, the questionnaires used in studies of dietary intake only asked a couple questions on how much red and/or processed meats people typically ate. Now the science needs more.
When it comes to processed meat, researchers are looking closely at nitrate and nitrite. These chemicals, added to many processed meats, lead to potential carcinogens known as N-nitroso compounds. For burgers and other red meats, grilling and broiling them well-done can form heterocylic amines (HCAs) and polycyclic aromatic hyrdocarbons (PAHs), also potential carcinogens. Continue reading