March is Colon Cancer Awareness Month in the United States and seven plant-based medical doctors have teamed up on Instagram to educate the public about one of the most lethal yet highly preventable cancers in existence.
Every weekday in March there’s a new post by one of the doctors to help educate and protect you. Here’s the team:
Dr. Angie Sadeghi (@angie.sadeghi)
Dr. Will Bulsiewicz (@theguthealthmd)
Dr. Sarina Pasricha (@docsarina)
Dr. Vanessa Mendez (@plantbasedgutdoc)
Dr. Danielle Belardo (@theveggiemd)
Dr. Garth Davis (@drgarthdavis)
Dr. Mauricio Gonzalez (@dr.mauriciogonzalez)
Colorectal cancer is a worldwide problem
Did you know that there were 1.8 million new cases and more than 850,000 deaths from colorectal cancer worldwide in 2018? The United States and United Kingdom accounted for almost 10 percent of those cases, alone. Yet some estimate that 60-80 percent of those deaths could be prevented through a combination of lifestyle and screening.
Altogether, colorectal cancer is the third most commonly diagnosed cancer and the fourth leading cause of cancer-related death worldwide and sadly, the problem is getting worse.
Colorectal cancer rates are expected to jump up to 2.2 million new cases and 1.1 million deaths by 2030. This increase can be attributed to an aging population, more cases in young people, and a shift towards a Western diet in countries like China and Brazil.
Colorectal cancer in the West
You'll find the highest rates of colorectal cancer in Westernized countries: North America, Europe, New Zealand, and Australia. In an attempt to combat this problem, many of these countries have started a colon cancer screening program.
For example, a colonoscopy is recommended for most adults at age 50 in the US, or earlier if there is a family history. Canada does stool testing beginning at age 50. In the UK, a colonoscopy is done at 55 and then stool testing begins at 60. In Australia, stool testing begins at age 50.
The colon cancer screening program in the United States has resulted in a reduced colorectal cancer incidence in people age 50 years and older, a testament to the screening program. However, there has been a dramatic and scary rise in colorectal cancers in younger adults less than 50 years of age. For example, in the US someone born in 1990 has four times the risk of rectal cancer and twice the risk of colon cancer compared to someone born just 40 years earlier.
Prevention is possible, and it starts with a plant-based diet
We have more control over cancer than we think and our nutritional choices are the best way to exert that control. The research is clear: to reduce our risk of colorectal cancer, we need to reduce consumption of red and processed meats, and increase fiber.
Let's start with meat. According to the World Health Organization, for every 100 grams of red meat, and 50 grams of processed meat, that we consume a day, we are increasing our overall risk of colon cancer by 18 percent.
To put that in perspective, a single 6 oz sirloin has about 200 grams of red meat, the average jumbo hot dog has 57 grams of processed meat, and four strips of bacon have about 51 grams of processed meat. After a comprehensive review of the evidence, the WHO classified processed meats as a Group I carcinogen and red meat as potential carcinogen (Group 2A).
Lifestyle and colorectal cancer
Differences in lifestyle can have a profound effect on colorectal cancer risk. For example, African Americans were found to have 50 times the risk of getting colon cancer when compared to native Africans. A shocking difference.
To say double would be a lot, but we're saying literally 50 TIMES. Why is this so? The diets are radically different, with the native African diet being significantly lower in animal protein, animal fat, and saturated fat compared to African Americans.
Fiber has also been shown to reduce the risk of colon cancer. A group of studies involving 1.7 million individuals found that those eating more fruit were 10 percent less prone to colorectal cancer, and another study of almost 200,000 people found that eating 35 grams of fiber per day reduced the risk of colon cancer by 40 percent. Keep in mind, you'll only find fiber in one place – plants. And we’re not talking about using a fiber supplement here. We’re talking about getting it in the real deal.
The power of fiber
Lastly, when it comes to those patients that have already been diagnosed with colorectal cancer, a study published in JAMA Oncology found that patients who ate a higher fiber diet had a lower risk of death. After being diagnosed with colorectal cancer, a simple increase of five grams of fiber per day was associated with a 22 percent reduction in colorectal cancer-specific mortality and a 14 percent reduction in all-cause mortality. Also, a 20-gram increase in whole grain consumption per day was linked with a 28 percent decrease in colorectal cancer death, while the risk of all-cause mortality was reduced by 12 percent.
Taken in sum, the solution is clear: more plants, less meat. Ideally, a whole food plant-based diet.
Prevention is more than just diet, we need to be vigilant
But that said, colorectal cancer is a threat even if you eat a whole food plant-based diet. We should still go out of our way to protect ourselves.
Colorectal cancer can be prevented by removing pre-cancerous polyps called adenomas. If adenomas are present in the colon and not discovered, they can slowly grow and eventually transform into cancer. We believe this growth process into cancer takes 10-15 years.
Unfortunately, adenomas are common, with about 30-40 percent of people developing an adenoma in their lifetime. We do not know exactly what causes them, but it seems clear at this point that it’s a combination of genetics, diet, and lifestyle.
If discovered, adenomas can be painlessly removed during a colonoscopy. Removal of the abnormal tissue prevents colorectal cancer, which obviously is a great thing. But it only works if you manage to find the adenoma.
One of the problems is that adenomas are often asymptomatic. However, as they grow in size and turn into cancer they can potentially cause symptoms of rectal bleeding, anemia, abdominal pain, change in bowel habits and colon blockage. When these warning signs are present, we need to acknowledge and act on them because time is of the essence.
Therefore, to protect ourselves we should take advantage of the colon cancer screening program that’s available in our respective countries. Also, if you develop symptoms of rectal bleeding, anemia, abdominal pain or change in bowel habits you should discuss it with your doctor. It may be appropriate to pursue additional testing and protect yourself from this dangerous condition.
And finally, please join these seven plant-based doctors on Instagram and help us spread awareness by sharing their posts and using the hashtag #doctorsagainstcoloncancer.
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