Colorectal Cancer: Studies Shows Dietary Changes, Ivermectin and Fenbendazole Can Shrink Tumors (2025)

Colo-rectal cancer is a type of cancer that Chadwick Boseman (Black Panther) and Robin Gibb (Bee Gees) died from. Rates of colorectal cancers, especially among young people, have been rising in the United States and other countries in the industrialized world, according to a recent American Cancer Society report.

Colon cancer in the United States accounted for 7.6 percent of new cancer cases in 2024, and 8.6 percent of deaths, according to the National Cancer Institute (2024). An estimated 53,000 people will die from colon cancer this year.

The good news is that we have a growing body of evidence—both high-quality scientific studies and patients’ personal experiences—that shows that diet and lifestyle changes can effectively stop cancerous cells in their tracks.

Related: Colorectal Cancer: Types, Risk Factors, Symptoms, Diagnosis, Staging and Treatment

One of the recent, and promising of these studies was performed on mice by a team of ten researchers at the University of Michigan.

The study, “Dysregulated Amino Acid Sensing Drives Colorectal Cancer Growth and Metabolic Reprogramming Leading to Chemoresistance,” was published in November 2022 in the journal Gastroenterology. For this study, scientists investigated how low-protein diets affected colon cancer cell growth.

More specifically, they studied something called mTORC1 activation in animal and human tissue.

What is mTORC1? 

mTORC1 are molecules that are sensitive to nutrients and that are thought to be hyperactivated when people have cancer. These molecules are implicated in 70 percent of human cancers, including colorectal cancers.

Other animal studies have shown that inhibiting mTORC1 appears to also inhibit tumor growth. Some medications that interfere with mTORC1 signaling pathways have also been found to inhibit tumor growth. However, these cancer-blocking pharmaceuticals are “limited in use,” according to Medical News Today, both because of their negative immune-suppressing side effects and because of the return of tumors once the drugs are stopped.

At the same time, a 2015 study showed that restricting protein intake decreased mTORC1 tumors in mice.

That study, which was done by an international team of researchers from the United States and Italy, mentioned that “reduced dietary protein intake and intermittent fasting (IF) are both linked to healthy longevity in rodents, and are effective in inhibiting cancer growth.” The scientists hypothesized that the reason may be the “down-regulation” of the mTORC1 pathways. Although the study focused on breast cancer, the authors concluded that their work suggested that protein restriction “may represent a highly translatable option for treatment not only of cancer, but also other age-related diseases.”

Restricting Protein to Inhibit Colon Cancer

For this new research, the scientists found that in the presence of amino acids mTORC1 activation was higher. They then examined how colon cancer tumors in mice would respond to two weeks on a protein-restricted diet followed by four weeks of chemotherapy.

Mice are usually fed a diet that is 21 percent protein. For this experiment, the researchers fed the mice diets that were just four percent protein.

They discovered what they had expected: Mice fed low-protein diets had less mTORC1 activation and less tumor growth than controls.

More specifically, reducing the intake of two amino acids—leucine and cystine—seemed to signal nutritionally to deactivate mTORC1.

This effect is not just in mice. When the scientists tested human colon cancer, they found that the samples with the most genetic markers of mTORC1 tended to have the worst outcomes.

Seed Oil-Driven Inflammation Linked to Human Colon Cancer: 2024 Study

A 2024 study (published in BMJ) by a group of researchers investigating the origins of colon cancer found evidence that excessive omega-6 plays a role.

After years of the American Heart Association and others claiming seed oils have a protective effect against cancer, this study represents a smoking gun providing solid evidence to the contrary.

This suggests avoiding seed oils will help prevent colon cancer, and likely also help people previously treated for colon cancer to prevent recurrence. It was made possible due to advances in toxicology that enable us to identify myriad short-lived molecules that develop during the oxidation of polyunsaturated fatty acids. These toxic PUFA oxidation products provide a constant signal to turn on the cellular inflammatory response system.

Starving Cancer 

Cancer cells grow exponentially. In order to proliferate so quickly, they need nutrients. Some of the nutrients they need are synthesized inside the cells themselves, but other nutrients—including amino acids—come from a person’s diet.

The reason why a low-protein diet appears to be effective in limiting tumor growth in the colon is that depriving the colon cancer cells of protein essentially starves them.

“Feeding or starving cancer cells is … complicated,” Jeffrey Nelson, surgical director of The Center for Inflammatory Bowel and Colorectal Diseases at the Mercy Medical Center in Baltimore, Maryland, told Medical News Today. “But this research shows that depriving certain amino acids influences the mTORC1 pathways leading to cell death.”

The China Study

Dr. T. Colin Campbell, Ph.D., a Cornell-trained biochemist, and director of the Center for Nutrition Studies, has published over 350 research papers, most of which are peer-reviewed. In his landmark book, “The China Study,” which was first published in 2005, Campbell and his son Thomas, a medical doctor, explored why the protein fad diets, so popular in the 1970s (and beyond), are not optimal for human health.

Instead, the research presented in the book, which was based partly on several longitudinal nutrition studies of large numbers of adults and their families that were conducted in China and Taiwan from 1983 to 1990, showed that a mostly plant-based diet, one that was lower in protein and higher in dietary fiber and whole foods, appeared to lead to the best health outcomes. A 55-minute film, “The China Study Documentary,” is also available on the T. Colin Campbell Center for Nutrition Studies’ YouTube channel.

People in China who lived in places where the regular diet was one that included smaller amounts of animal protein were less likely to get diabetes, cancer, and heart disease. 

Chris Beats Cancer 

Chris Wark was diagnosed with Stage III colon cancer when he was just 26 years old. After undergoing colon surgery to remove the cancer, he made the controversial decision not to follow his conventional doctors’ recommendations to do chemotherapy. Instead, Wark turned to nutritional and alternative healing, a journey that he documents in his bestselling 2018 book, Chris Beats Cancer.

As detailed in the book, Wark’s cousin Jeff was also diagnosed with colon cancer: Stage IV. Jeff was told that the cancer was not curable. With chemotherapy, he could live up to two years. Without it, he would die in six months, according to the doctors. Although Jeff’s mother urged him to talk to his cousin, Jeff told his mother that he and Chris were very different people and that he “didn’t buy into fads or self-help books.” 

Although the surgery to remove the cancer appeared to be successful, chemotherapy made him sick and depressed. Tumors began growing in his liver and abdomen. Jeff died three months after his diagnosis. He was 49 years old.

But the idea of poisoning himself back to health using chemotherapy made no sense to Wark. Instead, he adopted an all-whole foods organic raw diet, found a holistic oncologist who was willing to treat him using a natural and non-toxic approach, and also sought out alternative treatments, including counseling, acupuncture, and chiropractic care. Nearly two decades later, Wark is cancer-free, the father of two, the author of three bestselling books, and the host of a popular podcast.

“I eliminated everything in my life that may have contributed to my [cancer],” Wark told The Epoch Times.

Colorectal Cancer: Ivermectin and Fenbendazole

A rapidly growing subcategory in the treatment of cancer is the utilization of prescription drugs originally approved for treating conditions other than cancer. Such off-label use of drugs has taken the world of integrative oncology by storm. 

This is a review of 13 case reports of ivermectin and/or fenbendazole for colorectal cancer. Read more at "

Fenbendazole and Ivermectin for Colorectal Cancer".

Colorectal Cancer and Aspirin

Interestingly, research has shown colonoscopies may be unnecessary if you're taking daily aspirin. While this may sound too good to be true, researchers found that aspirin can, in fact, eliminate certain cancerous tumors, such as liver tumors. (R)

A systematic review and meta-analysis published in 2017 (R, R) also concluded that aspirin was as effective for preventing colorectal cancer incidence and death thereof as screening with flexible sigmoidoscopy or FOBT, and aspirin was actually more effective for preventing death from cancer in the proximal colon. As reported by the authors of that analysis (R):

"The effect of aspirin on colorectal cancer mortality was similar to FOBT and flexible sigmoidoscopy. Aspirin was more effective than FOBT and flexible sigmoidoscopy in preventing death from or cancer in the proximal colon. Aspirin was equally effective as screening in reducing colorectal cancer incidence, while flexible sigmoidoscopy was superior to FOBT.

Conclusions: Low-dose aspirin seems to be equally effective as flexible sigmoidoscopy or guaiac FOBT screening to reduce colorectal cancer incidence and mortality, and more effective for cancers in the proximal colon. A randomized comparative effectiveness trial of aspirin vs. screening is warranted."

There is even a study (R) of over 600,000 men and women in which aspirin use at least 16 times per month was associated with a 40% reduced risk of colon cancer mortality over the six-year study period.

A 2016 study in JAMA Oncology also found aspirin use staved off colorectal cancer. This study included nearly 136,000 people who were followed for 32 years. Taking either a 325 mg tablet or an 81 mg tablet at least twice a week reduced overall cancer incidence by 3%, the risk for gastrointestinal cancer by 15% and colorectal cancer by 19%.

What might explain these findings? Well, there are several potential mechanisms by which aspirin can be helpful against cancer, including the following:

• Aspirin is a prostaglandin inhibitor, so it can help address hormone imbalances that contribute to colorectal cancer development
• It lowers your iron, which is another potential cancer contributor
• It has anti-inflammatory effects
• It has anti-lipolytic effects, so it inhibits insulin resistance and Type 2 diabetes, both of which are risk factors for cancer
  

If you decide to implement this recommendation it is likely that taking one regular aspirin a day, preferably with your largest meal to avoid any gastrointestinal damage, would be the best strategy. If you are taking blood thinners, are very sick, or are on multiple medications, using willow bark would likely be a safer option.

Related: Aspirin Inhibits Metastatic Cancer Spread, Reducing Mortality by 21 Percent: November 2023 Study

Best Natural Aspirin Alternative and Aspirin Purchasing Guidelines

If you decide to use aspirin, avoid coated extended-release versions due to their additives. Opt for immediate-release aspirin, which can be found on Amazon. Check the inactive ingredients list carefully — corn starch should be the only one listed. 

If you're sensitive to aspirin, consider using a salicylic acid or willow bark supplement instead. When you take aspirin, your body metabolizes the acetylsalicylic acid into salicylic acid, which is responsible for aspirin's anti-inflammatory, pain-relieving and antithrombotic effects. This compound is naturally found in willow bark.

Willow bark stands out as a compelling natural alternative to aspirin, embodying the age-old wisdom of traditional medicine. Unlike synthetic pharmaceuticals, willow bark's active compounds have coexisted with human biochemistry for millennia, resulting in a natural affinity that modern drugs struggle to replicate.

This harmony stems from our ancestors' long-standing consumption of small amounts of these compounds, allowing our bodies to adapt and utilize them efficiently.

While 240 mg to 600 mg of willow bark extract (15% salicin) is often estimated to provide a salicin dose that is roughly equivalent to 325 mg of aspirin, due to the differences in metabolism and bioavailability between salicin and aspirin, the total amount of willow bark extract needed is typically larger.

For dosage, to approximate the effects of 81 mg of aspirin, you would need 400 mg to 800 mg of willow bark extract standardized to 15% salicin. To match the effects of 111 mg of aspirin, you would need 500 mg to 1 gram of willow bark extract standardized to 15% salicin.

Overall, aspirin is a versatile and underappreciated medication with a wide array of health benefits beyond its well-known cardiovascular applications. From cancer prevention to potential treatments for liver disease and cognitive decline, aspirin's diverse effects warrant further research and consideration.

Its metabolic impacts and potential to influence hormone balance add another layer to its therapeutic potential. The breadth of aspirin's potential benefits suggests that this common, inexpensive medication may have more to offer than health authorities are acknowledging in supporting overall health and preventing various chronic conditions.

Colon Cancer and Vitamin D

Numerous epidemiologic studies have shown that higher intake or blood levels of vitamin D are associated with a reduced risk of colorectal cancer (Gandini 2011). Nine studies were identified for analysis on vitamin D blood level and colorectal cancer.

Coffee for Colorectal Cancer

In a large group of patients with metastatic colorectal cancer, consumption of a few cups of coffee a day was associated with longer survival and a lower risk of the cancer worsening, researchers at Harvard-affiliated Dana-Farber Cancer Institute and other organizations report in a study published by JAMA Oncology (2020).

The findings, based on data from a large observational study nested in a clinical trial, are in line with earlier studies showing a connection between regular coffee consumption and improved outcomes in patients with non-metastatic colorectal cancer. 

Exercise Helps Colon Cancer Survivors Live as Long as Cancer-Free Peers

In a 2025 study published in the American Cancer Society, researchers from Louisiana State University (LSU) found that exercisers with colon cancer may live approximately as long as those without it.

The authors assessed data from two post-treatment clinical trials involving 2,876 people with stage 3 colon cancer. Stage 3 colon cancer means that the cancer has spread beyond the colon to nearby lymph nodes but hasn’t yet reached distant organs. Participants self-reported their exercise levels following cancer surgery, as well as during and after chemotherapy. Researchers then compared this data with that from the general population, matched according to sex, age, and year.

The pooled data from the two trials indicated that among the 1,908 individuals alive in the third year following cancer treatment, those who engaged in less than three MET (metabolic equivalent) hours had a 3.1 percent lower likelihood of surviving three additional years, whereas those exercising 18 or more MET hours per week had a 2.9 percent higher likelihood of survival.

Three MET hours is the equivalent of one hour of brisk walking, while 18 MET hours equate to five hours of brisk walking, lead author Justin C. Brown of the Louisiana State University Health Sciences Center told The Epoch Times in an email.

“This new information can help patients with colon cancer understand how factors that they can control—their physical activity levels—can have a meaningful impact on their long-term prognosis,” said Brown in a press statement.

This study builds on findings from a 2022 study by the same group of LSU researchers. The earlier study suggested that exercise can prevent, as opposed to delay, cancer recurrence. Findings demonstrated that in patients with a history of colon cancer, those who were physically active had improved survival rates three years after surgical resection compared to those who were inactive.

Protecting Your Colon Health Starts With Protecting Your Gut Health

The health of your gut affects that of your entire body, which is why protecting your colon health shares many of the same principles as protecting your gut health. For instance, according to one study, dried plums (i.e. prunes) may lower your risk of colon cancer by building your gut bacteria.13

Adequate fiber is also important. For every 10 grams of fiber you add to your daily diet, your risk of colon cancer decreases by 10%.14 Well-cooked vegetables are your best source of fiber. Overall, I believe about 25 to 50 grams of fiber per 1,000 calories consumed daily is an ideal amount to aim for.

Fermented foods are also gaining recognition as an important tool for both gut health and disease prevention, including colon cancer. For example, butyrate, a short-chain fat created when microbes ferment dietary fiber in your gut, has been shown to induce programmed cell death of colon cancer cells.15

In short, eating a high-vegetable, fiber- and fermented food-rich diet is key for preventing colon cancer, and the reason for this is directly related to the way it affects your gut microbiome. According to one study, "intestinal bacteria can act in concert with diet to reduce or increase the risk of certain types of colorectal cancer."16

Keep in mind, though, that while fiber can nourish your microbiome, it can also feed the endotoxin-producing gut bacteria unless your gut health is optimal, so it’s important to properly introduce fiber-rich foods into your diet. 

Avoid Antibiotic-Laden CAFO Meats and Processed Meats

Both processed meats and red CAFO meats have been linked to colon cancer, and it's important to understand that many of these contain antibiotic residues as well as other compounds that may influence your cancer risk.

Processed meats, such as bacon, ham, pastrami, salami, pepperoni, hot dogs and some sausages, are those preserved by smoking, curing, salting or adding chemical preservatives. The nitrates found in processed meats are frequently converted into nitrosamines, which are clearly associated with an increased risk of certain cancers.

A 2007 analysis by the World Cancer Research Fund (WCRF) found that eating just one sausage a day may raise your risk of bowel cancer.17 Specifically, 1.8 ounces of processed meat daily — about one sausage or three pieces of bacon — was found to raise your likelihood of cancer by 20%.

Research also suggests that people who eat the most red meat (in one study this was 5 ounces a day) have a 24% greater risk of colorectal cancer than those who eat the least.18 Red meat is likely not the problem in and of itself, however; the way it's cooked, and the source it comes from, likely play a role. Grass fed beef, for instance, contains cancer-fighting compounds.

When it comes to meats, I recommend eating organically raised grass fed meats only and cooking them only lightly (rare, not well-done). For the record, I believe most people need some animal protein to be optimally healthy, but most eat far more protein than is necessary.

What Else Can Lower Your Risk of Colon Cancer?

Colorectal cancer is the third most common cancer in the U.S., aside from skin cancers, as well as the fourth leading cause of cancer-related deaths in women, and the third in men.19 More than 95,500 cases of colon cancer were expected to be diagnosed in 2017, according to the American Cancer Society, so taking steps to prevent it is important.

It's important to avoid the unnecessary use of antibiotics, not only due to their potential link to colon cancer but also for a myriad of other reasons. Be mindful of choosing organic, antibiotic-free meats and dairy products as well. In terms of other methods to lower your colon cancer risk, there are many lifestyle-based changes you can make, including:

1. Eat more vegetables — Vegetables contain an array of antioxidants and other disease-fighting compounds that are very difficult to get anywhere else — like magnesium. Results from one meta-analysis indicated that for every 100-milligram increase in magnesium intake, the risk of colorectal tumor decreased by 13%, while the risk of colorectal cancer was lowered by 12%.20 Beyond magnesium, plant chemicals called phytochemicals can reduce inflammation and eliminate carcinogens, while others regulate the rate at which your cells reproduce, get rid of old cells and maintain DNA. Alice Bender, MS, RD, a nutritionist for the American Institute for Cancer Research, says the evidence on fiber and colon cancer, while mixed, is strong enough to make recommendations. “Our 2007 expert report looked at all the studies and concluded that foods high in fiber, not necessarily the fiber itself, can lower risk for colorectal cancer,” she tells WebMD. “We know that a plant-based diet rich in fruits, nonstarchy vegetables, legumes, and whole grains is associated with a lower risk of a number of the most common cancers – colorectal, stomach, mouth, pharynx, larynx, and esophageal” Bender says.
2. Optimize your vitamin D levels — Vitamin D deficiency is a risk factor for colorectal cancer. In one study published in the journal Gut, people with higher blood levels of vitamin D were less likely to develop colorectal tumors.21 This may be because vitamin D is beneficial for your immune system, which in turn may help to limit the growth of cancerous tumors.
3. Exercise — There is convincing evidence that regular exercise can significantly reduce your risk of colon cancer.22 One study revealed that physically active men and women have about a 30% to 40% reduction in the risk of developing colon cancer compared with inactive persons, for instance.23
4. Limit your alcohol intake and quit smoking — Both excessive alcohol intake and smoking are associated with an increased risk of colorectal cancer. When it comes to alcohol, I generally define "moderate" alcohol as a 5-ounce glass of wine, a 12-ounce beer or 1 ounce of hard liquor, with a meal, per day. I do recommend eliminating all forms of alcohol. If you're a smoker, you can find tips for quitting here.
5. Maintain a healthy weight and control belly fat — A number of studies have linked obesity to an increased risk for about a dozen different cancers, including cancer of the colon. In a 2014 study that analyzed data from more than 5 million people over the age of 16, every 11-pound increase in body weight was associated with an increased risk for 10 types of cancer.24 If you're overweight or obese, even small amounts of weight loss can lead to significant benefits for your health. In terms of cancer prevention, losing excess belly fat is particularly important, as belly fat is linked to an increased risk of colon cancer regardless of your body weight.
6. Optimize carbohydrate intake — The other part of the equation is carefully modulating your carbohydrate intake. Carbohydrates play a role in supporting mitochondrial function since glucose is the preferred fuel for energy production at the cellular level. Tailor your carbohydrate consumption to support a healthy microbiome by aiming for about 250 grams of targeted carbohydrates daily for most adults. Individuals with higher activity levels may require more. Introduce carbohydrates gradually to allow your gut to adapt, thereby minimizing digestive issues and endotoxin levels. Begin with white rice and whole fruits to nourish beneficial bacteria before considering vegetables, whole grains and starches. Avoiding high-fiber diets initially is important if your gut microbiome is compromised, as excessive fiber will increase endotoxin levels. If your gut health is severely compromised, focus on easily digestible carbohydrates like dextrose water for the first week or two. Sip it slowly throughout the day to support gradual gut healing.

Frequently Asked Questions (FAQs) About Gut Health and Colon Cancer

Q: Why are more young adults getting colorectal cancer?

A: Poor diet, processed foods, gut microbiome imbalances, and environmental toxins are major factors driving the rise.

Q: What are the early warning signs of colorectal cancer?

A: Unexplained weight loss, persistent abdominal pain and changes in bowel habits are key symptoms to watch for.

Q: How does gut bacteria affect colon cancer risk?

A: Harmful bacteria like Fusobacterium nucleatum and pks+ E. coli produce toxins that damage DNA, increasing cancer risk.

Q: How do processed foods increase cancer risk?

A: They fuel harmful gut bacteria, trigger inflammation, damage mitochondria and create conditions for cancer to grow.

Q: What steps can I take to protect my gut and lower cancer risk?

A: Remove vegetable oils from your diet, reduce toxin exposure, balance your carb intake, limit antibiotic use and introduce Akkermansia after improving diet for six months.

Key Take-Aways

“Cancer cells are not alien invaders,” Chris Wark (author of bestselling 2018 book, Chris Beats Cancer) reminds his readers. “Cancer cells are your cells with your DNA. Cancer is not just in you, it is you. The presence of cancerous tumors is the result of a breakdown in the normal functioning of your body … Cancer is a condition created by the body that the body can resolve, if given the proper nutrition and care.”

The University of Michigan research suggests that dietary and lifestyle changes—limiting protein intake as well as restricting calories—may help thwart cancer growth and also make chemotherapy more effective.

 
Whether you choose a conventional treatment plan or an alternative one, it appears that in order to stop colon cancer from proliferating in your body, limiting your exposure to known carcinogens (which include glyphosate, some volatile organic compounds, and certain pharmaceutical medications and injections), along with eating a lower protein diet, will help you take back your health.

This article has been edited to include additional information. The original version of the article was published on The Epoch Times.

This article is part of the diet and cancer series. Other diet and cancer related articles in the series:

• Best Anti Cancer Supplements

• Ivermectin for Colorectal Cancer?

• Expert Explains Cancer May Be Metabolic Disease, and Shares a Cure

• Eat These Foods to Starve Cancer Cells to Death

• Could yogurt help protect against colorectal cancer?

• Hydroxychloroquine and Pancreatic Cancer

• Hyperthermia, Sauna, Immunotherapy and Vitamin C for Cancer

• Shocking News About Beans, Peas, Oat Cereals and Potatoes

• An 11-year retrospective case series using multiple nutritional and herbal agents (2017 update)

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• 9 Clin Microbiol Rev. 2013 Apr; 26(2): 231-254
• 10, 11 Los Angeles Times April 4, 2017
• 12 Washington Post May 19, 2015
• 13 Science Daily, September 25, 2015
• 14 Nutr Cancer. 2005;53(1):117-25
• 15 Nutrients 2024, 16(4), 529
• 16 Medical News Today January 27, 2017
• 17 Nutr Cancer. 2008; 60(2): 131-144
• 18 Cancer Res. March 15, 2010;70:2406
• 19 American Cancer Society, Colorectal Cancer
• 20 The American Journal of Clinical Nutrition Volume 96, Issue 3, September 2012, Pages 622-631
• 21 Gut January 15, 2015
• 22 J. Nutr. November 1, 2002 vol. 132, no. 11 3456S-3464S
• 23 Medicine & Science in Sports & Exercise, November 2003 - Volume 35 - Issue 11 - pp. 1823-1827
• 24 Lancet. 2014 Aug 30;384(9945):755-65