MCFAs are rapidly converted into ketone bodies since they are primarily absorbed directly to the liver via the portal vein and transferred independently of the carnitine shuttle system to the mitochondria.

Dear Isabel. Thus cancer cells have then no or limited access to these MCT's FA. And ketones cannot be metabolized by cancer cells. In other words, MCT fatty oils are oke to consume. Is this correct? Thanks very much for your answer. Very much appreciated. Marcel

Dear Isabel. Know that currently I'm not on a KD. I consume about 60 to 80 g of carbs on a daily basis. Reason is that I have cancer. Marcel

Dear Marcel, like you I am also a chemist but retired (age 75). My wife and I started keto 15 nov 2015 and are still very low carb. Maybe not keto. We started for her sake >20 years of depression with good results (because keton bodies have been proven beneficial for brain energy). Because I was afraid of causing us harm I was and still am interested in scientific evidence concerning keto. Your question: the key factor in our diseases of civilisation (cancer inclusive) is insulin. Certainly not natural fat (like cocos oil that has 60% medium chain fatty acids). Insulin is a storage hormone and as such a growth factor. It is raised by intake of sugar but remember starch (bread) has a higher glycemic index than sucrose. If you eat 2 slices of bread your insulin and serum glucose will stay elevated for at least 150 min as if you drank 75 g of glucose solution (OGTT test). Cancer cells thrive on glucose. If you take a snack or a soft drink in between meals you will remain all the time in hyperglycemia (and hyperinsulinemia). That is far more disturbing than any oil consumption that has nearly no impact on your blood sugar level.

Dear Marcel: MCT FA are favored in some, but not all, ketogenic dietary therapies. You might look at Seyfried TN et al. "Ketogenic metabolic therapy, without chemo or radiation, for the long-term management of ID H1-Mutant glioblastoma: an 80 month follow-up case report." Frontiers in Nutrition 2021. doi:10.3389/fnut.2021.682243

Best wishes,, Isabel

Isabel, thanks for the reference and Eric I think you two have made a wise decision. We also eat little carb-rich products and more fat but not keto.

Cancer cells also thrive on glutamine. Any thoughts?

Yes, but I know that DON, 6-Diazo-5-oxo-L-norleucine, inhibits glutamine metabolism but in order to starve cancer cells you also need to inhibit beta-oxidation (certainly if you have prostate cancer (Koltai et al)) and FAS. Glucose inhibition is relatively easy (Koltai et al).

Koltai et al have recently published 2 books, one on prostate cancer and on cancer in general. Working on it.

From a therapeutic dietary perspective, managed macro and micro nutrient intake can help. To decrease glutamine, for example, protein can be restricted, which is a hallmark of classic ketogenic diet. There are many, many ways to enhance one's individualized regimen. On a large scale, constituents of milk fat exhibit several anticarcinogenic effects. On a small scale, something as simple as substituting green tea for other caffeinated beverages may help a bit ("Epigallocatechin gallate (EGCG), a green tea polyphenol, has numerous pharmacological effects, one of which is to inhibit GDH The effects of EGCG on GDH have been used to kill glutamine-addicted cancer cells during glucose deprivation or glycolytic inhibition and to suppress growth of neuroblastoma xenografts." Hensley et al., 2013).

Many thanks for your answers Isabel!