NMU 100 – High Glycemic Diet Increases Colon Cancer Risk
Nutrition / Natural Medicine Update No 100 (August 15, 2018)
with Dr. James Meschino
Topic: High Glycemic Diet Increases Colon Cancer Risk
Source: American Journal of Clinical Nutrition (August 2018)
An important study was published in the American Journal of Clinical Nutrition in August 2018. The findings combined data from two long-running studies: The Health Professionals Follow-Up Study, whereby researchers have followed the dietary patterns and health parameters of over 46,000 male health practitioners in the U.S. (from 1986-2012), and the Nurses’ Health Study, which has followed the dietary and health parameters of over 74,000 female nurses in the U.S. (from 1984-2012).
The diet of each of the more than 120,000 health practitioners was assessed every four years during the 26-year follow-up period. In this portion of the study, researchers assessed the glycemic nature of the individual diets, which means looking at the extent to which the diet would elicit a high blood sugar and high insulin secretion response – something known as the Empirical Dietary Index for Hyperinsulinemia (EDIH). They then correlated the glycemic potential of each person’s diet with risk of colorectal cancer.
The results showed that for men, those with the highest glycemic diets had a 33% increased risk of developing colon cancer compared to men adhering to the lowest glycemic dietary pattern. For women, women consuming the highest glycemic diets had a 22% increased risk of colon cancer compared to women who followed the lowest glycemic dietary pattern. This is important because previous studies have shown that very sugary/starchy diets (high glycemic diets) that promote high blood sugar and increase the release of insulin, as well as high insulin states, such as pre-diabetes, type 2 diabetes, and insulin-dependent diabetes, are all associated with increased risk of colo-rectal cancer.
A high-level of insulin promotes more rapid cell division of the cells that line the colon and rectum, which in turn, results in a greater risk of genetic mutations occurring – some of these mutations may produce cancerous changes resulting in colon cancer development. The researchers conclude, “the findings (of this study) suggest that the insulinemic potential of diet may partly underlie the influence of dietary intake on colorectal cancer development”.
Over the years studies have shown that 70-90% of colon cancer cases can be prevented through more prudent dietary and lifestyle factors. Keeping your fasting blood sugar level below 5.0mmol/L or more ideally 4.7 mmol/L (90 mg/dl or 85 mg/dl, respectively) is one way to help reduce risk (possibly by 26%, when combining data for men and women).
Other ways to reduce the risk of colorectal cancer include:
- Reducing or eliminating intake of high-fat animal products (with exception of fish), along with deep fried foods, breaded meats, creamy salad dressing, and foods loaded with trans-fats
- Consume at least 1000 mg per day of calcium from food and/or supplements
- Maintain a vitamin D blood level above 75nmol/L
- Ensuring that you consume at least 400 mcg per day of the B-vitamin, folic acid
- Reducing or eliminate alcohol intake
- Avoiding or reducing the intake of smoked meats, charred meats, BBQ-meats and meats cooked to high-temperatures
- Avoiding foods preserved with nitrates and nitrites
- Maintaining adequate intake of dietary fiber
- Remaining at your ideal body weight
- Engaging in regular physical exercise
- Not smoking
All these nutrition and lifestyle strategies have been shown to help reduce the risk of colo-rectal cancer to varying degrees. When you combine all these strategies into a comprehensive wellness game plan, the risk of colon cancer and many other degenerative disease (including heart disease, Alzheimer’s disease and other forms of cancer) can be markedly reduced. I would encourage you to review the list of these strategies again, as together they pave the way to helping to optimize your healthy life expectancy – the number of years you are likely to have a highly functioning body and mine. Of course, having regular colonoscopies (usually after the age of 50) to find and remove any polyps is also a vital prevention strategy in preventing colon cancer development. Remember that colo-rectal cancer is the second leading cause of cancer death in our society when you combine statistics for men and women. So, having a colo-rectal cancer prevention strategy is an important part of your overall wellness game plan.
I have included a link to the research studies cited here, in the text below
1. Tabung F, Wang, W, Fung, T, et al. Association of dietary insulinemic potential and colorectal cancer risk in men and women. Am J Clin Nutri. 2018, 108(2):363-370. https://academic.oup.com/ajcn/article-abstract/108/2/363/5036567?redirectedFrom=fulltext
2. C-peptide as a Marker of Insulinemic Response to Diet https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1829170/
3. Assessing Insulin Response: https://www.ncbi.nlm.nih.gov/books/NBK278954/
Eat Smart, Live Well, Look Great,