Sugar-cancer connection is a myth, according to Mayo Clinic

This was posted in my doctor's office today:

Myth: People with cancer shouldn't eat sugar, since it can cause cancer to grow faster.

Fact: Sugar doesn't make cancer grow faster. All cells, including cancer cells, depend on blood sugar (glucose) for energy. But giving more sugar to cancer cells doesn't speed their growth. Likewise, depriving cancer cells of sugar doesn't slow their growth.

This misconception may be based in part on a misunderstanding of positron emission tomography (PET) scans, which use a small amount of radioactive tracer — typically a form of glucose. All tissues in your body absorb some of this tracer, but tissues that are using more energy — including cancer cells — absorb greater amounts. For this reason, some people have concluded that cancer cells grow faster on sugar. But this isn't true.
For other myths, see:

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Nutriionist at my oncologist's office told me anything white is not good because of the chemicals that turn the product white i.e., ...white bread, white sugar, white flour.
Also, from the get-go, when I first was diagnosed, I was told to use raw sugar (not brown sugar, but raw) if I needed sweetening at all. I like it now and white sugar or even splenda is too sweet for me.
I'm glad, however, to read that the myth about sugar making cancer grow faster is a myth, but I'll stick with the raw sugar.

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Researchers from the Harvard Medical School as well as many, many others say otherwise. So many clinical studies have been done on the effects of sugar and cancer that I cannot go along with the Mayo Clinic. Sorry!

Blessings and hugs!!!

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It seems you are told TO or NOT TO consume something, then a few years later they come back with the opposite. Who knows.... I guess you just gotta use your own judgement ;)

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This is how I'm thinking....I'm going to keep on trying to keep as much sugar as I can out of my diet, and if it turns out that sugar wasn't bad for me, then that's okay anyhow because I'm not hurting myself by not eating it. But if it is really true that it is bad, then I've helped myself in the long run, right? That way I'm covered whichever way it turns out :)

Blessings and hugs!!!

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I agree with Kate...Your damned if your do your damned if you don"t....I just eat and drink whatever I can on any given day.......Use your own judgment.Whats right for me may not be right for you I have always consumed everything in moderation .So why change now and go to one extreme or the other...May you all have the best of health possible as we all battle the cruddy cancer.....

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The Mayo report is correct in that sugar doesn't cause cancer to "grow faster". All cells need "glucose" to survive. If there is a loss of glucose uptake, then all cells die, including the healthy ones.

In healthy cells glucose uptake is regulated by certain growth factors that regulate metabolism. Unfortunately cancer cells are able to maintain metabolism using a special protein, even when the growth factors are absent.

That having been said, the points made about moderation and healthy diet are key in that they take care of the healthy cells so that we can better fight the cancer we have, withstand the treatments we need, and feel better overall so that we can enjoy living.

I had a pretty healthy diet before, and am trying to do even better now. However, even though sugar is empty calories and has no nutritional value, I never beat myself up when I indulge in the occasional cup of ice cream. :-)

Best to all.

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Well, I have to agree with abbaschild and disagree with the Mayo Clinic. Sugar is bad for cancer. It is not a myth. I stopped sugar... my cancer slowed down. I got upset and started eating it 5 years later and my cancer started to grow. Who knows... but I choose to stay away from it. Cancer cells definitely suck it up quicker. That is why IPT for cancer works well. Insulin Potential Therapy. They use a little sugar with the chemo and it goes right to the cancer cell and leaves the good cells alone.
You have to believe in whatever you do. Sometimes, that alone, will cause that something to work well.

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abbaschild, Can you post a link from the Harvard Medical Studies regarding sugar and cancer? I would like to read them.

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I've actually have never heard of this until now. Glad I didn't either. I adored my chocolate during chemotherapy.

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Here is how sugar really affects cancer cells:
"The German biologist Otto Heinrich Warburg won the Nobel Prize in medicine for his discovery that the metabolism of malignant tumors is largely dependent on glucose consumption. In fact, the PET scan commonly used to detect cancer simply measures the areas in the body that consume the most glucose. If a particular area stands out because it consumes too much sugar, cancer is very likely the cause.
When we eat sugar or white flour - foods with a high glycemic index, blood levels of glucose rise rapidly. The body immediately releases a dose of insulin to enable the glucose to enter cells. The secretion of insulin is accompanied by the release of another molecule, called IGF (insuline growth factor), whose role is to stimulate cell growth. In short, sugar nourishes tissues and makes them grow faster. Furthermore, insulin and IGF have another effect in common: They promote the factors of inflammation, which also stimulate cell growth and act, in turn, as fertilizers for tumors. Today we know that the peaks of insulin and the secretion of IGF directly stimulate not only the growth of cancer cells but also their capacity to invade neighboring tissues. Moreover, after injecting breast cancer cells into mice, researchers have shown that the cancer cells are less susceptible to chemotherapy when the mouse's insulin system has been stimulated by the presence of sugar. The researchers concluded that a new class of medications is needed now to fight cancer: medication that reduce insulin peaks and IGF in the blood.......
All the scientific literature points in the same direction: people who want to protect themselves from cancer should seriously reduce their consumption of processed sugar and bleached flour"
Read on in Dr. Servan-Schreiber's book "Anticancer"

Another thing to avoid is corn syrup that is in all kinds of processed foods and artificial sweeteners are poison too.

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If the Mayo clinic's article were true then how do you explain the fact that cancer is three times more common in diabetics? A recent scientific paper just came out proving that sugar and glutamine together cause a rapid increase in cancer growth. Glutamine is found in dairy and MSG. Recent studies on Glucophage, a drug used to lower blood sugar in diabetics has been shown to slow down cancer growth, especially breast, prostate and ovarian. A friend of mine who has been in a 12 year remission from malignant melanoma recently went on an ice cream binge and got a recurrence. Maybe it's a coincidence. All the same, I'm sticking to my low carb diet.

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Well I gotta add what I always add to these discussions. Cancer is bad enough, and if you have late stage ovarian cancer it will probably recur sooner or later no matter what you do. So I figure if it's gonna shorten my life anyway I'm gonna make the most of the time I have, which includes living and eating for pleasure. Among other things, that means I get to have premium ice cream at least twice a day :)

By the way, I've been doing the NED happy-dance since I finished chemo in April 2009.


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You do understand that Otto Heinrich Warburg won the Nobel Prize won almost 80 years ago in 1931? And that all of the cells in our bodies need glucose? And what works in animal studies most of the time does not work in humans? Just because someone writes a book does not make something true. Just like the internet--look at all the email junk you receive that when you research it, turns out not to be true. If all you had to do was remove sugar from your diet, don't you think none of us would be eating sugar. That this would have been studied and proven a long time ago? And let's not forget the story of Lorenzo's oil, where adding oil to the diet decreased the fatty acids around the myelin. The truth is nobody knows. One study, no matter which way it goes, really doesn't really mean anything. If you think that eliminating sugar increases your chance for survival--that's what you should do. I firmly believe moderation in all things and that's what I am doing. I really do not mean to tick anybody off but we all need to step back and not post our beliefs as truths until the scientific community as a whole agrees with us. Or at the very least throw on a "I believe."

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I have been a vegetarian to some degree for 36 years. The three years prior to my breast cancer in 1993 I was living on a low fat , mostly organic, Vegan diet with only natural sugar (honey, fruit concentrate) The year before my breast cancer I was totally sugar free, except of course that naturally occuring in fruits and vegetables.

As I begin my 2nd recurrence with OV CA I do not blame my diet but the BRAC2 gene.

i still believe in the value /importance of a plant based diet though I will have fish now on occasion if we eat out. And if I crave a chocolate chip cookie (or a chocolate malt (notice the recurring chocolate theme), I do not deny myself. Moderation in all things!

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A healthy diet for everyone includes carbohydrates, but complex are best. Sugar and sweets are not complex carbohydrates. I eat occasionally alittle something sweet but try not to eat much simple sugar products. Sometimes I am better than others, but I try. Aside from cancer it is not good for me since adult onset diabetes runs in my family.

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This research looked into glucose and tumor growth. The key is to block glutamine's affect on glucose absorption.

The researcher noted this about sugar and diet:
"Cancer patients should eat a balanced diet to promote good health. Cutting out sugar would not inhibit tumor growth, said Don Ayer, a professor of oncological sciences at the Huntsman Cancer Institute. Even with a sugar-free diet, there still would be plenty of glucose in the blood to feed cancer."

This is the full article regaridng the research:
U. researchers: Tumors hungry for sugar
Huntsman Institute » Findings point to new ways to fight cancer.

By Brian Maffly

The Salt Lake Tribune
Updated: 08/24/2009 09:48:06 AM MDT

Click photo to enlarge
U. oncological scientist Don Ayer. (Courtesy Huntsman Cancer Institute)

University of Utah biochemists have made a breakthrough in understanding how cancer cells feed on glucose, possibly paving the way for new drugs designed to starve cancer into submission.

Cancer cells use glucose in tandem with another crucial nutrient, the protein glutamine, an amino acid found in many foods, according to findings published this week by researchers at the Huntsman Cancer Institute. The findings could spur development of new chemotherapies that would stall tumor growth by deactivating cancer cells' ability to use glucose, said Don Ayer, a professor of oncological sciences whose lab published the research in the Proceedings of the National Academy of Science .

For decades, science has known that cancer cells suck up inordinate quantities of glucose, nature's ubiquitous biological fuel, in a process that quickly blows tiny tumors into deadly malignancies.

PET scans use cancer cells' high rate of glucose metabolism to build images of tumors. These cells also need glutamine, just like normal cells.

"It's absolutely clear you need both for tumor growth. They seem to need it more than other nutrients. If you deprive them of one or the other, tumors don't grow," Ayer said.

Mohan Kaadige, a postdoctoral researcher in Ayer's lab, spearheaded the study, whose co-authors include Ayer; Sadhaasivam Kamalanaadhan, also a member of the Ayer lab; and Ryan Looper, an assistant professor in the Department of Chemistry.
The lab's work, funded by the National Institutes of Health and the American Cancer Society, seeks to unlock the molecular mysteries associated with tumor proliferation.

"Research into the factors that regulate the metabolism and growth of cancer cells is still at an early stage," said Janet Shaw, a U. professor in the Department of Biochemistry and a former Huntsman researcher. "Dr. Ayer's discovery that glutamine and glucose utilization are linked is important because it identifies a number of new molecular targets that could be manipulated to interfere with the growth and survival of tumor cells."

This week's discovery builds on the lab's previous research identifying the role of MondoA, a protein that switches genes on and off, in tumorigenesis. This protein affects the gene TXNIP, which suppresses tumor growth by blocking glucose uptake into cancer cells. The Ayer team discovered that in the presence of glutamine, MondoA deactivates TXNIP. This is important because it suggests new ways to impede tumor growth.

"If you don't have glutamine, the cell is short-circuited due to a lack of glucose, which halts the growth of the tumor cell," Ayer said.

The next step is to learn how the Mondo protein works in relationship with glutamine.

"If you can modify the metabolism of the tumor cell you can have a benefit. This is not a new idea," Ayer said. "If we can figure out how glutamine signals to Mondo, that has quite a bit of chemotherapeutic potential."

Were it developed, a drug that blocks glucose uptake would not likely choke off normal cell growth, as many cancer chemotherapy drugs currently do because of their toxicity.

"Tumor cells seem to be addicted to glucose. Normal cells are not. They grow at a slower rate and if you challenge them with nutrient deprivation they can be more flexible," Ayer said.

Ayer emphasized that his lab's findings shed no light on dietary impacts on tumor growth. Glutamine is the most common amino acid in our bodies and glucose levels are tightly regulated by our endocrine system, regardless of sugar consumption.
Cancer and diet

The fact that cancer cells might die if deprived of glucose doesn't mean cancer patients should cut sugar out of their diets, researchers say.

Cancer patients should eat a balanced diet to promote good health. Cutting out sugar would not inhibit tumor growth, said Don Ayer, a professor of oncological sciences at the Huntsman Cancer Institute. Even with a sugar-free diet, there still would be plenty of glucose in the blood to feed cancer.

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Here is a good website that indicates glycemic load:

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