Warning: This article discusses cancer, which may be upsetting to some readers.
A bowel cancer surgeon has raised a critical alert for gym enthusiasts who frequently use protein powders.
As a person who goes to the gym a few times weekly, protein shakes have become quite the staple for me.
However, Dr. James Kinross, a consultant colorectal surgeon at Imperial College London, cautions that people should be cautious about their gut health.
The WHO indicates that by 2040, the global incidence of colorectal cancer is expected to rise to 3.2 million new cases annually.
With the increase in colon cancer rates globally, the microbiome scientist has explained why he views protein powders as a potential risk.
With two decades of experience in the field, Dr. Kinross has noted that limiting red meat consumption to just once a week is beneficial for gut health, emphasizing that bowel cancer can, in fact, be prevented.
Bowel Cancer Surgeon’s Protein Powder Alert
For those looking to build muscle, Healthline states that active individuals should aim for 1.2 to 2 grams of protein per kilogram of body weight.
Dr. Kinross, however, has observed a growing obsession—especially among men—regarding high protein intake, which he believes can be unhealthy in modern gym culture.
“These protein powders can be harmful to your gut. When proteins are broken down and metabolized, one of the byproducts can be toxins that cause inflammation and, in the long run, lead to bowel cancer,” he shared with LADbible.
“Moreover, high protein powders, including creatine, significantly alter your microbiome.”
The microbiome refers to the gut’s microorganisms, which can influence the risk of colon cancer by impacting inflammation, immune responses, and overall metabolism.
In addition to protein powders, highly processed foods containing additives—like instant noodles and sugary cereals—could elevate colon cancer risk by fostering inflammation and altering gut bacteria.
Instead of reaching for protein powders, Dr. Kinross suggests opting for plant-based proteins rather than animal-based options.
“And honestly, it’s best to steer clear of powdered fibers and those types of nutrition counters; they can be detrimental to your gut,” he advised.
The Connection Between Red Meat and Bowel Cancer
While red meat is typically viewed as a protein powerhouse, Dr. Kinross mentions it should be treated as an occasional indulgence.
“If you’re going to eat red meat, choose high-quality cuts and limit it to once a week. It should feel like a treat,” he noted.
He elaborated on the specific dangers, explaining that red meat contains an amino acid processed by the liver, potentially leading to harmful effects. “There’s a certain metabolite we suspect contributes to the risk.”
Alternatives to Red Meat
While Dr. Kinross advocates reducing red meat intake, he also recognizes that one doesn’t need to adopt a fully vegan lifestyle.
“Simply replacing a serving of red meat with white fish or chicken can significantly lower your risk of bowel cancer,” he highlighted.
“You don’t have to go completely vegan for a healthy gut—that’s a misconception. But having meat at every meal? Not a good idea.”
The Three Pillars of Bowel Cancer
According to Dr. Kinross, ultra-processed foods are only part of the equation, as he identifies three main contributors to colon cancer.
Genes
“The genetics you inherit play a role. We’re improving at identifying hereditary cancers, though only about 5% of bowel cancers are linked to genetics,” he explained.
Environment
“What you consume, along with environmental pollutants, can heighten cancer risk,” he added. This includes not just ultra-processed foods but also microplastics and other toxins present in our surroundings.
“Ultra-processed foods are often more affordable and accessible, making them the go-to for many, especially within deprived communities. Corporations are to blame for aggressively marketing these foods to young individuals and children,” he said.
Microbes
As previously noted, specific gut microbes are strongly linked to bowel cancer risk.
Dr. Kinross points out that the imbalance of beneficial bacteria is also a concern. “It’s not just that there are too many harmful bacteria; it’s also about lacking enough good bacteria,” he summarized.
Preventing Bowel Cancer Through Early Screening
“Catching bowel cancer in early stages can lead to complete recovery,” he is certain.
“In terms of screening, Scotland schedules colonoscopies at 50, while England is moving towards that age as well. But we have to adapt as the disease evolves.”
“If you have any concerns, please see your doctor. No matter if you’re experiencing bleeding or a change in bowel habits—just go. Be persistent in asking for appropriate cancer screenings.”
Dr. Kinross mentioned, “Colonoscopy is the gold standard, but there are simpler fecal tests available that can also highlight your risk for bowel cancer.”
Recognizing Bowel Cancer Symptoms
As outlined by the NHS, symptoms of bowel cancer might include:
- Changes in bowel habits
- Rectal bleeding
- A sensation of needing to pass stool even after doing so
- Abdominal pain
- A lump in the abdomen
- Bloating
- Unexplained weight loss
- Extreme fatigue without explanation
If you find yourself experiencing any of these symptoms and wish to talk to someone, consider reaching out to a support line, such as Macmillan’s Cancer Support Line available daily from 8 am to 8 pm.
