Does Sugar Feed Cancer Cells?

Does Sugar Feed Cancer Cells?

Esther Trepal, RD, MS, CDN answers reader questions about nutrition during treatment and beyond:

"I’ve been told it’s bad to eat sugar when you have cancer, but I crave it for energy. Should I avoid it completely?"

I’m assuming you are referring to the belief that sugar “feeds” cancer. This is one of those concepts that is oversimplified, and can be misleading. During digestion, sugar is broken down into glucose, which is the primary energy source for our cells, including tumor cells. But here’s a fact: all carbohydrates are broken down into glucose. Carbohydrates are found in wheat and other grains, cereal, fruit, and sweeteners of all kinds (including honey, molasses, and agave).

The real issue, to me, is how does that glucose get into the cell? And is there a way to modulate it? You may be familiar with a hormone called insulin. This hormone opens the cell for the glucose to enter. It is known as a hormone that promotes growth, not a favorable effect when we’re talking about tumors. When we eat carbohydrates and they reduce to glucose, the body responds by releasing insulin. The more glucose, the more insulin. By slowing down the release of glucose, you can prevent large spikes in insulin that promote uptake of glucose and growth of tissue.

I want to turn your question around a little. Rather than focusing on sugar, you should consider the quality of all the carbohydrates you are eating. What I call “high quality” carbs include whole foods and whole grains. For example, an apple is better than apple sauce is better than apple juice. Or brown rice is better than white rice. The “whole” aspect slows down the digestive process, thereby slowing the production of glucose. In turn, the release of insulin is more stable.

So, what about those cravings for sweets? Make no mistake, sugar is not a “health food.” But sometimes it is just what we need. Keep the amounts moderate and occasional. But remember, it’s not just the sugar. Cakes and pastries come with white flour, another poor quality carb. Consider making your own desserts with reduced amounts of sugar, along with increased amounts of fruit and whole wheat flour. You can also satisfy your sweet tooth with high quality carbs, such as fruit and some of the sweeter vegetables, such as sweet potatoes, winter squash, peas, carrots and beets.

Quick answer: Sugar feeds all cells, not just cancer cells and should be limited but not completely avoided.

12 Replies

  • Cancer is to do with environment and food intake!

    Sugar is in most of our pre prepared, so if we go for pre prepared food intake we may have a problem!

    If we cook our food from fresh veg and other things then we can limit the sugar.

    with cancer it is like a lottery, luck?

  • The experts that are truly interested in prevention, not sustaining the status quo, or just using drugs to attempt a cure, say that too much carbohydrate is the highest risk of cancer.

    because carbohydrate is the macronutrient cancer NEEDS

  • Very informative, thank you!

  • You're welcome.

  • I keep it simple by going whole-food organic. That's my "diet". A kind of organic mediteranian diet actually, but, I do have organic sugar and molasses in my morning coffee (organic), other than that it's an exception, a sandwich of home made bread (usually an oats mix). Carb desserts are rare, (pie, cake, etc) on holiday or birthday usually. But, I don't limit myself otherwise. I know the usual "warnings" will follow. Trust me I heard them all :) but, I agree with the OP, eating healthy whole-foods in general with "unhealthy" carbs occasionally I doubt hurts that much.

  • I disagree.

  • Would it be possible to offer an explanation?

  • I think culturally we've lost sight of what a moderate amount of carbohydrate is. Three hundred years ago apparently we ate less than four pounds of sugar a year, now the average is nearly 150lbs.

    Sugar and molasses are sugar, whether they're organic or not, and combined with the insulin spike caused by caffeine, that's not a healthy combination. This cultural acceptance of unhealthy behaviour, thinking it is healthy, sets us up for poor health. We may then be unable to cope with the stress of occasional, further unhealthy carbs. It depends how frequent 'occasional' is too; how do we know when the last atherosclerotic lesion has subsided, leaving us better prepared to cope with the next onslaught?

    With chronic inflammation due to excess insulin/IGF-1 from a high carbohydrate diet, organic or not, repair and recuperation will be poor.

    I hope that answers your query bala?

  • Thank you.

  • I believe chronic inflammation may be caused by unnatural substances foreign to the body (pesticides, hormones, antibiotics, gmos) affecting the pancreas, blood pressure, and other chronic conditions, as well as depleting vitamins. An organic whole food diet cuts out a lot, and a few things cleared up for myself. I actually eat less now, and my son's allergies cleared after years of having them, at his amazement too. I think there's something more to chronic inflammation than sugar and carbs. My blood pressure is still in the normal range and, if necessary, I'd look for things like cinnamon to control blood glucose. I do understand the warnings on white sugar, flour, hfcs, etc. however.

  • Thank you for your view Rusti.

    Fructose thickens blood seven times as much as glucose. That will definitely add to inflammation/blood pressure issues. It is a question of balance; when glycogen stores are full any excess will be turned to fat, that is why a high-fructose diet results in fatty-liver, and insulin-resistance the same as alcohol (fermented sugar). Added to that, it is high levels of IGF-1, stimulated by high-glycaemic carbs or anomalies such as baked beans or yoghurt, that result in narrowed arteries, by causing growth of the endothelial linings.

    By eating less overall, you may now be having a balanced amount of carbs; try calculating how much carbohydrate you eat now . However, remember this is a chronic condition (metabolic syndrome) that can take years/decades to manifest itself, or give detectable signs. How old are you?

    You are so right that toxins give our body more to fight, and refined foods, stripped of micro-nutrients, leave us susceptible to illness.

  • Well, I'm in my 60's though people don't take me for my age, so that's a good thing too, cuz I don't feel it :) Asthma has been good, and I'm not aware of any other problems, though I do want to watch out for diabetes having a bad diet for so long I'm sure it's already affected. Even so, I'd be dealing with it naturally, and with things like cinnamon. My problem is no longer overloading on anything so, I don't really get into cutting particular foods out as yet. Basically I try to stay balanced. Having a juicer like nutrabullet has helped me have a little more green veggies than I normally would. I'd recommend that to anyone. It's so easy and not too expensive.