Fasting has gained attention not just as a weight-loss trend, but as a potential way to lower the risk of serious diseases like colorectal cancer. New research, published in the journal PLOS ONE, shows that fasting may help slow tumor growth and even improve overall survival by 20% in people with colorectal cancer.
These effects are linked to how fasting changes the body at a cellular level. However, scientists warn that fasting alone is not enough to prevent cancer, especially since genetics also play a big role.
Fasting activates a natural process in the body called autophagy. This is like the body’s cleaning system—it removes damaged or aging cells and makes room for new, healthy ones.
According to a review in Public Health Toxicology, autophagy helps prevent the early steps that lead to cancer by reducing cell damage and keeping cells in good working order. When this process works well, it may reduce the chance of abnormal cells growing into tumors.
Fasting also seems to help the immune system fight off cancer more effectively. A study in Oncotarget found that fasting can reduce the number of certain immune cells in the tumor environment—called M2 macrophages—that usually help cancer hide from the body’s defense systems.
By changing the behavior of these cells, fasting may make it easier for the immune system to spot and destroy cancer cells early on.
In addition to possibly reducing cancer risk, fasting may even help people who are undergoing cancer treatment. A review by Bowel Cancer Australia looked at how fasting-like diets—such as time-restricted eating—might reduce the side effects of chemotherapy.
In some cases, fasting appears to protect healthy cells while making cancer cells more vulnerable to treatment. Although this research is still in early stages, it suggests that fasting could be a helpful part of cancer care in the future.
But fasting isn’t without risks. A study from MIT, reported in Medical News Today, showed that while fasting followed by eating again can help the gut renew itself, it might also speed up tumor growth in people who already have genetic risks.
This shows that fasting might be helpful for some, but harmful for others. It highlights the need for people to get medical advice before starting any fasting routine—especially if they have health issues or a family history of cancer.
There are many types of intermittent fasting (IF), which is a way of eating that includes planned periods of not eating. One of the most popular is the 16/8 method, where people fast for 16 hours and eat during an 8-hour window.
Other methods include the 5:2 diet (eating normally five days a week and cutting calories on two), alternate-day fasting, and the Warrior Diet (eating one large meal at night). Some of these fasting styles have been shown to reduce inflammation and support cell repair, which could play a role in lowering cancer risk.
Even traditional practices like Ramadan fasting, which involves not eating from sunrise to sunset, have drawn interest from scientists. One study showed that this type of fasting might reduce the relative risk of colorectal cancer by about 2.4%.
Still, fasting is not safe for everyone. People with diabetes, those taking certain medications, or individuals with a history of eating disorders should avoid fasting unless they’re under a doctor’s care. It’s always best to talk to a health care professional before making big changes to your diet.
Most importantly, while fasting may offer many health benefits, it’s not a complete shield against cancer. Genetics are a major factor, and many people at risk show no early warning signs. This is why screening is so important. Detecting cancer early can save lives.
Today, colonoscopy is still the most reliable method for finding colon cancer, but not everyone is comfortable with it. Fortunately, there are less invasive options. One such test is COLOTECT, developed by BGI Genomics.
It uses next-generation sequencing (NGS) technology to analyze stool samples for abnormal DNA methylation—one of the earliest signs that cancer may be developing. This test offers a simpler way to screen for colorectal cancer, especially for people who are at average risk or hesitant about colonoscopy.
In the end, fasting may help the body stay strong and resist disease, but it should be part of a bigger picture. Healthy lifestyle choices like eating well, staying active, and avoiding smoking are all important.
But the most powerful combination includes not just good habits, but also regular screenings to catch problems early. Tools like COLOTECT, along with smart lifestyle choices, give people the best chance to stay ahead in the fight against colorectal cancer.
If you care about cancer, please read studies about a new method to treat cancer effectively, and this low-dose, four-drug combo may block cancer spread.
For more information about cancer prevention, please see recent studies about nutrient in fish that can be a poison for cancer, and results showing this daily vitamin is critical to cancer prevention.
The research findings can be found in PLOS ONE.
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