Keto And Colon Cancer: Is There A Link?

The ketogenic, or keto, diet is a weight loss method that uses fat as the primary source of calories and drastically limits carbohydrates. Research has shown that certain types of diets are known to increase the risk of developing colorectal cancer. However, little is known about diets that may help prevent or treat it. Some studies have shown that a keto diet may help prevent and treat colorectal cancer by slowing the growth of tumours. However, it is important to note that the majority of these studies have been conducted on mice, and more research is needed to understand the effects of a ketogenic diet on humans.

Ketogenic diets may slow the growth of colorectal cancer

A ketogenic diet is a very high-fat and low-carbohydrate diet. It puts the body into a metabolic state where it uses fat for energy instead of sugars. This process is called ketosis, where fat is transformed into molecules known as ketone bodies.

Research has shown that certain diets can increase the risk of developing colorectal cancer. These include diets high in red meat, processed meats, sugar, or alcohol. However, little is known about diets that may help prevent or treat this type of cancer.

A study in mice suggests that a ketogenic diet may slow the growth of colorectal cancer. The study found that a compound produced while eating a ketogenic diet, called β-hydroxybutyrate (BHB), may inhibit the development of colorectal cancer. BHB binds to a receptor on epithelial cells, instructing them to stop dividing. The study found that mice with colorectal cancer that were fed a ketogenic diet had slower-growing tumours and lived longer. Similar results were seen when the researchers repeated the experiment using mice engineered to develop colorectal cancer.

The human body is resilient, and when food is scarce, it shifts from breaking down and using calories from the diet to dipping into its reserves of fat. Many studies have suggested that ketosis triggered by fasting may have health benefits, including reduced blood sugar levels and improved sensitivity to insulin.

The ketogenic diet has grown in popularity as a weight-loss method, and it does seem to help some people lose weight in the short term. Researchers have been intrigued about whether fasting and diets that mimic fasting, including the keto diet, could help prevent or play a part in treating cancer.

Human Studies

While the mouse study results suggest that a ketogenic diet can slow or stop the development of colorectal cancer and be used to treat existing cancers, the study leaders and other experts have warned that this does not mean a ketogenic diet or taking a BHB supplement should be used to prevent or treat colorectal cancer. Further studies on BHB's effects in humans are needed before any conclusions can be made about its role in cancer prevention or treatment.

BHB is widely available as a dietary supplement marketed for weight loss, but its risks and benefits need further study. Clinical trials are being set up to test ketone supplementation in people with colorectal cancer, as well as to see the ketone's potential anticancer effects in other parts of the body.

Potential Side Effects

While a ketogenic diet may have potential benefits in slowing the growth of colorectal cancer, it is important to note that it may also have unintended side effects. In mice with pancreatic and colorectal cancer, a keto diet accelerated a lethal wasting disease called cachexia, which contributed to about 2 million deaths per year. Patients and mice with cachexia experience loss of appetite, extreme weight loss, fatigue, and immune suppression.

In conclusion, while ketogenic diets may slow the growth of colorectal cancer, further research is needed to understand its potential benefits and side effects fully. It is important to consult with a healthcare professional before starting any new diet, especially for those who are already managing a health condition.

Obesity is a risk factor for colorectal cancer

The pooled RRs of colorectal cancer for the obese vs. normal category of BMI were 1.334 (95% CI, 1.253–1.420). There was heterogeneity among studies of BMI (P<0.001) but not among studies of WC (P = 0.323). Both general and central obesity were positively associated with the risk of colorectal cancer in this meta-analysis.

When the analysis was stratified by proximal colon and distal colon, the results showed that there was a strong association for higher BMI levels with proximal colon cancer or distal colon cancer. There was no statistically significant heterogeneity among studies of BMI (proximal colon cancer: P = 0.058, I2 = 40.5%; distal colon cancer: P = 0.798, I2 = 0%).

When the analysis was stratified by sex, the pooled RRs of colorectal cancer from male and female studies for the obese vs. normal categories of BMI were 1.467 (95% CI,1.363–1.579) and 1.153 (95% CI, 1.078–1.234), respectively. The pooled RRs of colorectal cancer from male and female studies for the highest vs. lowest categories of WC level were 1.477 (95% CI, 1.300–1.677) and 1.442 (95% CI, 1.296–1.604), respectively.

The mechanisms that might underlie the association between excess weight and colorectal cancer remain unclear. Two hormonal systems – the insulin/insulin-like growth factor (IGF) axis and adipokines (adiponectin and leptin) – are the most studied candidates. First, the involvement of insulin and IGF-1 in colorectal carcinogenesis has been supported by experimental and clinical studies. Circulating total IGF-I, a major determinant of free IGF-I concentrations, is associated with increased risk of colorectal advanced adenomas and cancer. The main reason is that increased free IGF-I, with concomitant changes of environment mitogenesis and anti-apoptosis in the cellular, favour tumour formation. Moreover, there is an increased risk of colorectal cancer development associated with type 2 diabetes.

Second, previous studies have demonstrated that the fat itself can also influence colorectal cancer risk. Adipocytes and preadipocytes could promote proliferation of colorectal cancer cells. Fatty acid synthase overexpression has been shown to be associated with colorectal cancer phenotype. Adipokines such as adiponectin, leptin are also associated with the risk of colorectal cancer. Adiponectin, as an insulin-sensitizing agent and a negative regulator of angiogenesis, is secreted mainly from visceral adipose tissue, which could inhibit colorectal cancer growth in animal models, and its circulating concentrations were associated with colorectal cancer risk in clinical trials. Leptin could also favour colorectal cancer growth in vivo and in vitro experiments as a pleiotrophic hormone being mitogenic, anti-apoptotic, pro-angiogenic, and proinflammatory in various cellular systems. The relationship between circulating leptin concentrations and colorectal cancer risk has been demonstrated.

The ketogenic diet can help a person lose weight

The keto diet is so filling that people can lose weight without counting calories or tracking food intake. One review of 13 studies found that a very low-carb, ketogenic diet was slightly more effective for long-term weight loss than a low-fat diet. People who followed the keto diet lost an average of 2 pounds more than the group that followed a low-fat diet. Another study in 34 older adults found that those on a ketogenic diet for 8 weeks lost nearly five times as much total body fat as those on a low-fat diet.

The ketogenic diet can also help people with type 2 diabetes, as it can improve insulin sensitivity and blood sugar management. A small study in women with type 2 diabetes found that following a ketogenic diet for 90 days significantly reduced levels of hemoglobin A1C, a measure of long-term blood sugar management.

However, there are some potential drawbacks to the keto diet. It can be challenging to maintain, and some people may experience "keto flu" symptoms such as poor energy and mental function, increased hunger, sleep issues, nausea, digestive discomfort, and poor exercise performance. Long-term risks may include kidney or liver problems, and there is a potential for nutrient deficiencies if a variety of recommended foods are not included in the diet.

While the keto diet may be an effective weight-loss strategy for some, it is important to consult with a healthcare professional before starting any new diet, especially one that involves significantly reducing carbohydrate intake, such as the keto diet.

The ketogenic diet may be beneficial for people with certain types of brain cancer

The Ketogenic Diet and Cancer

The ketogenic diet, or keto diet, is a high-fat, low-carbohydrate diet that has gained popularity as a weight loss method. This diet causes the body to burn its own fat by producing ketones, which can serve as an emergency fuel source. While the long-term safety and effectiveness of the keto diet are still unknown, recent studies suggest that it may have potential benefits for people with certain types of cancer.

Keto Diet and Brain Cancer

The keto diet has been suggested as a possible adjuvant therapy for brain cancer, particularly malignant gliomas. Glioma is a collective term for tumours that arise from glial cells in the brain, with astrocytoma being the most common form. The survival rate for glioma is low, and current treatments have limited effectiveness. However, research indicates that the keto diet may be a beneficial adjunct to standard treatments such as surgery, radiation therapy, and chemotherapy.

A clinical trial involving 15 subjects with glioblastoma multiforme (GBM), the most aggressive form of primary brain cancer, found that combining the keto diet with standard treatments was feasible and well-tolerated. The keto diet was started concurrently with radiation and chemotherapy, and continued for six weeks. This approach did not add any significant side effects and resulted in weight loss for all participants.

Another study published in the July 2021 issue of *Neurology®* examined the use of a modified keto diet, specifically the modified Atkins diet with intermittent fasting, in 25 people with astrocytomas. The diet was found to be safe and feasible, with no serious side effects. It led to changes in metabolism in the body and brain, including increased ketone concentrations. However, the study was not designed to determine the impact on tumour growth or survival rates.

Keto Diet and Colorectal Cancer

In addition to brain cancer, the keto diet has also shown potential benefits for colorectal cancer. Studies in mice have found that a ketone called β-hydroxybutyrate (BHB) produced during ketosis can slow the growth of abnormal cells in the colon and colorectal cancer cells. When treated with BHB, these cancer cells seemed to "start sleeping" instead of dying.

While these findings are intriguing, experts caution that they do not provide sufficient evidence to recommend the keto diet or BHB supplements for preventing or treating colorectal cancer in humans. Further clinical trials are needed to understand the role of BHB in cancer prevention and treatment.

The ketogenic diet may offer potential benefits for people with certain types of brain cancer, such as astrocytoma and glioblastoma multiforme. However, more research is needed to confirm these findings and fully understand the role of the keto diet in cancer treatment. It is important to consult with healthcare professionals before starting any new diet, especially for individuals with cancer or other health conditions.

The ketogenic diet may not be suitable for cancer patients without medical supervision

The ketogenic diet has been a topic of interest for cancer researchers in recent years. While it has been shown to have some positive effects on cancer in mice, it is not necessarily a suitable diet for human cancer patients without medical supervision.

A ketogenic diet is a very high-fat, low-carbohydrate diet that can put the body into a state of ketosis, where it burns fat for energy instead of glucose. This diet has been shown to slow the growth of abnormal cells in the colon and colorectal cancer cells in mice, suggesting it may be a potential avenue for preventing or treating colorectal cancer.

However, it is important to note that these studies were conducted on mice, and mouse metabolism is different from human metabolism. Therefore, the results may not translate directly to human cancer patients. In fact, one potential issue with the keto diet for cancer patients is that it may be difficult to maintain weight and muscle mass, which are already threatened by the disease.

Additionally, while the keto diet can help with weight loss, it is not yet clear if this weight loss can be maintained long-term. Obesity is a risk factor for developing colorectal cancer, so the keto diet may help reduce this risk. However, this does not mean that it is suitable for cancer patients who are already overweight or obese, as it has not been proven to be effective in humans, and it may be challenging for those already struggling with weight-related health issues.

Furthermore, the keto diet has been shown to have unintended side effects in mice with cancer. It accelerates cachexia, a lethal wasting disease characterized by loss of appetite, extreme weight loss, fatigue, and immune suppression. This disease is common in patients with progressive cancer and can make it difficult for them to handle anti-cancer treatments.

Therefore, while the ketogenic diet may hold some promise for cancer prevention or treatment, it is not suitable for cancer patients without careful medical supervision. More research is needed to understand the effects of this diet on human cancer patients, and it should not be used as a replacement for standard treatments without the recommendation of a patient's oncologist.

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