Colorectal Cancer Prevention
Updated: Jun 30, 2022
Prevention is infinitely preferable in cost and human suffering than treatment after-the-fact. For instance, lung cancer was the most common cause of death in the 1960’s when most people smoked and now it is a rare condition among non-smokers. Similarly, there is compelling evidence that a high fiber, low carbohydrate diet has huge potential for reducing colorectal cancer (CRC). In the same way that lung cancer was reduced by eliminating the root cause (smoking), new cases of CRC might be reduced by 93% (a staggering 1.2 million cases a year) by reversing the fiber to carb ratio in our staple foods. Accomplishing this goal requires a paradigm shift in prevention nutrition and would depend on convincing people of the need to change behavior and the affordability and availability of equally acceptable alternative foods.
The Evidence
Colorectal cancer (CRC) is the third commonest cancer after lung, prostate and breast cancer affecting 1.3 million every year but has been increasing by 6% per year in young adults for at least the past 25 years. Any increase in incidence of a disease over a short time implicates an environmental root cause. In the case of CRC there are well established biological mechanisms that suggest excess high glycemic carbohydrates and near universal fiber deficiency of barely 10g/day in their food is the most likely explanation for the increased CRC in young adults.
Cheap industrially produced foods based on high glycemic starches and sugars make up between 50%-60% of average food consumption and this is a major contributor to obesity, and pre-diabetes estimated to affect half of Americans. With the type of food available in our stores and restaurants it is almost impossible to achieve adequate fiber intake at the same time as minimizing blood glucose and insulin spikes from high glycemic foods. For instance, on one hand it takes 1.7kg of broccoli to achieve the RDA of 40g fiber a day (20g per 1000 kcal) but getting 40g of fiber from whole wheat flour comes along with 1000 kcal of high glycemic starch which creates high blood glucose and insulin levels contributing to weight gain and insulin resistance. However, the recommended daily amount of fiber is likely to be insufficient for CRC prevention which most likely requires in excess of 50g per day.
Even before this recent surge in new cases of CRC it has always been a problem in Western Societies with an annual incidence of 65 per 100,000 as opposed to 1.5 per 100,000 in East Africa where fiber consumption is at least 100g/day (Hadza Study) whereas average US fiber intake is 10-15g/day. Could it be possible to prevent over 95% of CRC cases in the USA with a change in our staple diet? The evidence suggests this might be so:
High glycemic carbohydrates dominate modern diets
60% of foods we now consume are made from rapidly digested starch and sugars
Fiber Gap: only 5% of the population achieves recommended fiber consumption.
Butyric acid is an absolutely essential nutrient and cell signaling molecule for colonic epithelial cells. Its absence produces an energy crisis and malfunctioning of colon lining cells.
On the other hand, butyrate promotes apoptosis (cell death) in colonic cancer cells.
Butyrate is produced by bacterial fermentation of fiber and the amount of butyrate produced is proportional to the amount of non-digested carbohydrate entering the colon.
The currently available food environment fosters an irremediable “Fiber Gap” between recommended and actual dietary fiber consumption unless supplements are used.
It has previously been difficult to achieve a low carb, high fibre macronutrient profile but this is can easily be achieved replacing flour and sugar in staple baked goods with Fiberflour and Fibersugar available from www.lonjevity-foods.com. We have produced a blend of general purpose baking flour that dramatical reverses the carb to fibre ratio, 14%:42% in FiberFlour versus 70%:12% in whole-wheat flour. Our solution makes behavior change easy, in fact redundant as we provide the ingredients to turn junk food into therapeutic functional food that eliminates glucose and insulin increases after meals while providing 7 sources of prebiotics to optimize microbial diversity and provide substrate for butyrate and other SCFAs.
A word of warning to the LCHF community who emphasize high meat and fat consumption and underplay the importance of prebiotics. Fiber deficiency can devastate microbial diversity and short chain fatty acid production. Diets dominated by meat and fat have been demonstrated to increase the risk of CRC while high fiber has been shown to reduce these risks through proven mechanisms.