Do different types of carbohydrates (glucose, fructose, etc) feed cancer cells more efficiently than other types?

Asked on November 29, 2014
Created November 27, 2014 at 7:52 PM

I am very active in the weight room and have been considering adding white rice for a little extra energy for my workouts. However, the whole "carbs feed cancer" idea has been stuck in the back of my head ever since I first heard it. I obviously care about my overall health more than just my workouts, so if adding rice (predominantly glucose) is just as effective at feeding cancer cells (still not even sure if that's an accurate claim) as other forms of carbohydrates, I won't do it. Thanks!

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on November 28, 2014
at 03:17 PM

Yeah, carbs feed cancer cells only if they already exist, but they also cause higher ROS in mitochondria over beta-oxidation (burning fat), higher glycation - especially via fructose, so keeping carbs generally low is a good idea.  This doesn't mean you should go zero carbs, but it's a good idea to keep it on the lower end of the spectrum, and it's a good idea to do something like a 2-7 day fast once a year.


You can do certain things such as eat carbs by themselves, away from protein and away from fat.  Away from fat because carbs trigger insulin to a higher level than protein, so if you eat carbs with fat, you're pushing digested fat into fat cells at a higher rate.  Away from protein due the glycation.  You could do intermittent fasting i.e. skipping breakfast in order to go into autophagy and allow for repairs.


You could eat carbs later in the day to slow down the cortisol response so you don't wind up with a high added chronic stress.


Fructose is safe after a fasted workout because at that point your liver will preferrentially convert it to glycogen instead of triglycerides.  Part of the danger with fructose is that it's a higher glycator of protein than glucose, tends to feed existing cancer cells at a faster rate than glucose, and depletes liver enzymes because it's processed nearly the same way as alcohol.  So maybe an hour or so after working out, fruit would be a good choice.


There also seems to be a correlation between overall insulin secretion and cancer growth as well as estrogen and cancer growth.  Certainly not all cancers follow this, but keeping your carbs on the lower side will cause you to secrete less insulin overall. 


Carrying less body fat will prevent aromatase from converting testosterone to estrodiol, so this is a plus as well.  Avoiding estrogenic environmental toxins such as plasticizers from BPA, and even BPA-free items is a good idea.  Avoiding hot takeout in plastic, styrofoam containers, bottled water, or using or touching plastic as much as possible would help.  Switch to things like glass, stainless stell, and silicone when possible. 


Things like DIM and other estrogen blockers can help, though they may have side effects with mitochonrial ATP production.


Mind you most of the damning evidence against fructose exists because people do stupid things like drink 2 liters of soda a day.  They generally don't apply to eating a bunch of fruit (though consuming 2 liters of juice would have the same detrimental effect.)


There's apparently some pathway in the liver that when consuming fish oil (any n3 PUFAs really) and fructose toghether, or alcohol and fish oil may trigger carcinogenic pathways, so that's another thing to avoid.


Most of the current research on cancer says that it's caused by damage to the mitochondria which triggers a whole bunch of changes in both the host cell and the mitochondrion to disable apoptosis, make teleomerase and prevent beta-oxidation.  This doesn't apply to every cancer, but certainly many.


It would probably be a good idea to go into autophagy every so often, either through IF or full on long fasts because this triggers cellular repair including apoptosis and the reabsorption of broken mitochondria - this doesn't guarantee that you won't get cancer, but it makes it more likely that repairs or apoptosis will happen before a cell becomes cancerours. 


Certainly environmental carcinogenic toxins and ionizing radiation are still triggers for cancer and should be avoided.


But overall, I wouldn't sweat the occasional cup of white rice, or fruit.



on November 29, 2014
at 11:16 AM

Thanks for the detailed explanation!

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on November 28, 2014
at 02:56 PM


Dietary sugar is not associated with any major types of cancer. If you already have cancer it might be different.

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