Pancreatic tumor cells use fructose to divide and proliferate, U.S. researchers said on Monday in a study that challenges the common wisdom that all sugars are the same.
Tumor cells fed both glucose and fructose used the two sugars in two different ways, the team at the University of California Los Angeles found.
They said their finding, published in the journal Cancer Research, may help explain other studies that have linked fructose intake with pancreatic cancer, one of the deadliest cancer types.
“These findings show that cancer cells can readily metabolize fructose to increase proliferation,” Dr. Anthony Heaney of UCLA’s Jonsson Cancer Center and colleagues wrote.
“They have major significance for cancer patients given dietary refined fructose consumption, and indicate that efforts to reduce refined fructose intake or inhibit fructose-mediated actions may disrupt cancer growth.”
I found some suggested meal plans on the USDA’s official My Plate site, which I’ll share in another post. Whole milk isn’t on the meal plan for breakfast, but orange juice and strawberry-flavored (i.e., sugary) skim milk are. Remind me again … which of those drinks contains fructose and which doesn’t?
Scientists at Johns Hopkins have identified a compound that could be used to starve cancers of their sugar-based building blocks. The compound, called a glutaminase inhibitor, has been tested on laboratory-cultured, sugar-hungry brain cancer cells and, the scientists say, may have the potential to be used for many types of primary brain tumors.
The Johns Hopkins scientists, inventors on patent applications related to the discovery, caution that glutaminase inhibitors have not been tested in animals or humans, but their findings may spark new interest in the glutaminase pathway as a target for new therapies.
Glutaminase is an enzyme that controls how glucose-based nutrients are converted into the carbon skeleton of a cell. Additional enzymes that help construct the so-called “bricks” of the carbon skeleton are controlled by a gene called IDH1. In some brain cancer cells, IDH1 is mutated and the resulting enzyme grinds up the bricks into nutrients that feed cancer cells.
Yes, yes, I know what you’re thinking: if blocking the glucose pathway slows cancer growth, why not just tell people to stop eating foods that spike glucose? Well, I’m pretty sure the answer lies in the fact that scientists have applied for patents. You can’t patent dietary advice, but you can patent a drug.
The drug metformin, a mainstay of diabetes care for 15 years, may have a new life as a cancer treatment, researchers said.
In a study in mice, low doses of the drug, combined with a widely used chemotherapy called doxorubicin, shrank breast-cancer tumors and prevented their recurrence more effectively than chemotherapy alone.
The findings add to a growing body of evidence that metformin, marketed as Glucophage by Bristol-Myers Squibb Co. and available in generic versions, could be a potent antitumor medicine.
In the report, being published in the Oct. 1 edition of Cancer Research, a journal of the American Association for Cancer Research, researchers said the combination of metformin and doxorubicin killed both regular cancer cells and cancer stem cells.
In contrast, doxorubicin alone had limited effect on the stem cells.
Mice that grew tumors generated from human breast-cancer cells have remained tumor-free for nearly three months on the combined treatment, while tumors have recurred in those not given the diabetes remedy.
Researchers said the results have potentially broad implications for cancer treatment.
Hmmm, now why would a drug given to type 2 diabetics be effective against cancer? You have to read pretty far down the article to find out:
How metformin affects cancer isn’t certain, but one possibility is that it deprives tumor cells of sugar.
“Cancer cells are gluttons for glucose,” said George Prendergast, president and chief executive officer of Lankenau Institute for Medical Research, Wynnewood, Pa. “It is likely that metformin is taking advantage of this gluttony of the cancer cell in order to attack it.”
Cancer cells are gluttons for glucose … I’ll be sure to think about when I’m drinking my USDA-approved skim milk with added sugar.
The link above is to an observational study based on food questionnaires, so it doesn’t exactly meet the gold standard for research. Nonetheless, here’s the conclusion:
The positive associations of glycemic index and load with colorectal cancer suggest a detrimental role of refined carbohydrates in the etiology of the disease.
The next time some vegan zealot trots out an observational study showing a weak association between meat and cancer, you can reply with this one and explain that since glycemic load is strongly associated with colorectal cancer, you’re sticking with a low-glycemic diet – meat included. If the vegan zealot starts quoting the China Study, you can reply with this (sort of) China study of Chinese Americans:
These data indicate that increased eCarb (non-fiber carb) and total carbohydrate consumption are both associated with increased risk of colorectal cancer in both sexes, and that among women, relative risk appears greatest for the right colon, whereas among men, relative risk appears greatest for the rectum.
So get T. Colin Campbell’s high-carb diet out of my face.
This one isn’t a study; it’s a case report from 1995 of two pediatric cancer patients put on ketogenic diets. Here are some quotes from the abstact:
OBJECTIVE: Establish dietary-induced ketosis in pediatric oncology patients to determine if a ketogenic state would decrease glucose availability to certain tumors, thereby potentially impairing tumor metabolism without adversely affecting the patient’s overall nutritional status.
So all the way back in 1995, at least some doctors suspected that depriving cancers of glucose might help. Sheesh. Anyway …
RESULTS: Within 7 days of initiating the ketogenic diet, blood glucose levels declined to low-normal levels and blood ketones were elevated twenty to thirty fold. Results of PET scans indicated a 21.8% average decrease in glucose uptake at the tumor site in both subjects. One patient exhibited significant clinical improvements in mood and new skill development during the study. She continued the ketogenic diet for an additional twelve months, remaining free of disease progression.
Improvements in mood and skill development? No, no, no … low-carb diets make you depressed and irritable. I know that’s true, because I read it on Yahoo Health.
Compared to normal cells, cancer cells have a prodigious appetite for glucose, the result of a shift in cell metabolism known as aerobic glycolysis or the “Warburg effect.” Researchers focusing on this effect as a possible target for cancer therapies have examined how biochemical signals present in cancer cells regulate the altered metabolic state.
Now, in a unique study, a UCLA research team led by Thomas Graeber, a professor of molecular and medical pharmacology, has investigated the reverse aspect: how the metabolism of glucose affects the biochemical signals present in cancer cells.
In research published June 26 in the journal Molecular Systems Biology, Graeber and his colleagues demonstrate that glucose starvation — that is, depriving cancer cells of glucose —activates a metabolic and signaling amplification loop that leads to cancer cell death as a result of the toxic accumulation of reactive oxygen species, the cell-damaging molecules and ions targeted by antioxidants like vitamin C.
Hey, I don’t care if it’s an amplification loop that does the job or if the cancer cells just die off from a lack of fuel. The point is, once again we see that depriving cancer cells of sugars can kill them.
One of the yeah-but questions I’ve received frequently in emails is “But what about the Asians? They eat a lot more carbohydrates than we do, and they’re not all fat and diabetic!”
I usually reply that while it’s true that Asians eat more rice than most Americans, they don’t match our consumption of sodas, pasta, muffins, ice cream, pancakes, cereal and Little Debbie Snack Cakes. Their total carbohydrate consumption may not be higher than ours, and even if it is, they don’t still consume nearly as much sugar.
I’ve tried without success to find recent statistics on what Americans eat vs. what the Japanese and Chinese eat, but perhaps those figures wouldn’t be relevant anyway. After all, diabetes is becoming a huge problem in China, so we can no longer point to them as an example of people who eat a high-carb diet without becoming diabetic. My guess is that as their incomes rose, they began buying more sugary foods.
I did, however, manage to find some data from the late 1990s, when the “Asians eat a lot of carbohydrates but don’t become fat or diabetic” opinion was probably more accurate. So let’s look at what the data tells us.
The first thing that jumps out at me is that even in the late 1990s, American men were getting nearly one-fourth of their calories from sugar. Yeesh.
Plugging the figures above into Excel, here’s what we get for carbohydrate and sugar consumption:
Carbohydrate grams per day
As I suspected even before I ran the numbers, Japanese men do not (or did not in the late 1990s) consume more carbohydrates per day than American men. However, Chinese men do. So why weren’t the Chinese afflicted with diabetes in the 1990s? Well, take a look at these figures:
Sugar grams per day
In the 1990s, at least according to this study, Japanese men consumed slightly fewer carbohydrates overall than American men and significantly less sugar. The Chinese consumed more carbohydrates overall, but only about one-fourth as much sugar as American men.
The figures for women are similar. I won’t go through them all, but here are the numbers for carbohydrate and sugar intake:
Carbohydrate grams per day
Sugar grams per day
I think the message is clear: American got itself into a big ol’ health crisis largely by consuming too much sugar. If you’re metabolically healthy and enjoy rice, fine. It probably won’t hurt you. But if you want to remain metabolically healthy, stay away from sugar.
When Dr. Robert Atkins found himself with a patient who was particularly resistant to losing weight or stuck in a long weight-loss stall, he recommended what he called a Fat Fast: a diet of around 1,000 calories per day with 90% of the calories coming from fat. (This was a short-term intervention, not a long-term diet.) The idea was to force the patient into nutritional ketosis.
I’ve never tried going quite that high in fat (I feel better when I don’t skimp on the protein), but I know very high-fat diets have worked wonders for people. On the low-carb cruise a few years ago, I met a Swedish gentleman named Sten who’d been obese most of his life, but lost a ton of weight after he switched to diet of more than 70% fat. (That’s him with Chareva in the picture below. If you look closely at his shirt, you can see a picture of him with a pair of his fat-guy pants.)
Jimmy Moore also broke out of a cycle of creeping weight gain by switching to a diet of 80% fat. He’s now lost more than 70 pounds since last May.
If you’ve considered a Fat Fast, you may be asking yourself the same question I asked Jimmy Moore when he visited last July: what the heck do you eat to keep your fat intake that high? I like fat, but who the heck wants to gulp down heavy cream or butter every day? That sounds monotonous, even for fat-lovers.
Not surprisingly, low-carb cookbook author Dana Carpender (along with friends Amy Dungan and Rebecca Latham) decided to overcome that objection by writing a cookbook full of very high-fat recipes.
The Fat Fast Cookbook (available as Kindle book or PDF) isn’t a guidebook for stuffing yourself with thousands of calories of fat per day. You could certainly do that by eating multiple portions of the recipes, but the book is intended for people who want to try the kind of fat fast recommended by Dr. Atkins. Consequently, the recipes are for snacks and meals that are also low in calories.
Nearly a third of the book is dedicated to explaining the science behind a fat fast and the proper way to do one. Here’s an example of the research cited in an opening chapter:
Next, Kekwick and Pawan [the researchers in a 1956 study] put obese subjects on one of four different diets. The diets all had the same calorie count—1,000 calories per day—but the composition of those calories varied: 1,000 calories of a mixed or balanced diet, 1,000 calories with 90% from carbohydrate, 1,000 calories with 90% from protein, or 1,000 calories with 90% from fat. If it were true that a calorie is a calorie is a calorie, then patients should have lost roughly the same amount of weight on all four diets. Did they? No. Indeed, on the high-carbohydrate diet the patients actually gained a little weight, overall—on just 1,000 calories per day. They lost some weight on 1,000 calories per day of a balanced diet, and even more on 1,000 calories per day with 90% from protein. But overwhelmingly, patients lost the most weight on 1,000 calories per day when 90% of those calories came from fat. Kekwick and Pawan concluded, So different were the rates of weight-loss on these isocaloric diets that the composition of the diet appeared to outweigh in importance the intake of calories.
Finally, Kekwick and Pawan determined that a group of patients could maintain their weight on 2,000 calories per day of a mixed or balanced diet. Then they put them on a diet of protein and fat, but very little carbohydrate. They found that their patients could consistently lose weight on 2,600 calories per day so long as carbohydrate was sharply restricted. This was one of the early pieces of research establishing a standard low-carb, Atkins-style diet for long term weight loss and maintenance.
Before you jump in with both feet, however, Carpender and her co-authors provide some warnings. If you’re a diabetic on glucose-lowering medications (and perhaps even if you’re not), you should have a doctor supervise you before switching to such a radical change in diet. In fact, you may not to want to take up a fat fast as your first change in diet at all:
We are assuming that most people reading this are already on a low carbohydrate diet. If, instead, you have been eating American Standard (full of junk), or a low fat/high carbohydrate diet, whether of processed food or whole grains and beans, you have trained your body to run on glucose rather than fat. That can be changed, but it takes a transition period. Your body takes a few days to a few weeks to get with the program and create the enzymes necessary to burn fat for fuel instead of glucose. Because of this, going straight to a Fat Fast from a diet rich in carbohydrate will very likely make you feel awful for a few days—your body simply won’t know where to get energy. We very much recommend that you go on a standard low carbohydrate diet first—we’re big fans of The New Atkins For a New You, Dr. Atkins’ New Diet Revolution, and Protein Power.
Jimmy Moore weighs in (sorry, Jimmy, couldn’t resist the pun) in the introductory chapters to describe the mistakes he made with his previous low-carb diet and how a high-fat diet re-ignited his weight loss.
Then it’s on to the recipes – 50 in all — which are grouped by fat content.
In the Below 80% Fat (just barely below) category, there are recipes for Asian noodles, mini cheesecakes, broccoli-cheese soup, and a breakfast scramble. (Don’t ask me to post the recipes. I’m not giving way the authors’ work.)
In the 80%-83% Fat category, you’ll find hot cereal (with coconut and flax meal instead of grains), chocolate pudding, deviled eggs, creamed spinach, jalapeno poppers and stuffed mushrooms, among many others.
Moving all the way up to the 88% Fat and Higher category, you’ll find recipes for coconut flax bread, fettuccine alfredo (using shiratake noodles) and Mocha Mascarpone Mousse.
I haven’t had a chance to try the recipes yet, but they certainly look appealing. I don’t feel a need to go on a calorie-restricted fat fast, but I’ll add many of these dishes to my to-be-tried list just because they sound delicious.
By the way, there are recipes for salads and other less-indulgent dishes in the book as well. It’s just not as much fun to show pictures of those.
If you’re interested in trying a fat fast – or just want more recipes in your low-carb repertoire – I’d recommend giving this book a look. If the diet isn’t boring, you’re more likely to stick with it.
The topic, which was suggested by Jimmy, is Feeding Kids For Health. Since feeding our girls is mostly Chareva’s responsibility, I brought her into the episode, followed by the girls themselves. I think you’ll enjoy their insights on how to get kids to eat vegetables.
It’s 75 degrees today in Franklin. I’d say Spring has sprung. Good weather for some farm work.
While I was sitting at a desk writing software for a living last week, Chareva took advantage of the warmer weather and doubled the size of the chicken yard. All the fencing behind the barn (right side of the picture) is newly installed.
We haven’t let the chickens into that area yet because we still need to put a net over it. It wouldn’t do the chickens any good to peck some fresh ground and then get carried off by a hawk.
Chareva and the girls have also been working on getting the garden going.
Cardboard? Yeah, I wondered about that myself. Chareva tells me the cardboard prevents weeds and attracts worms.
This year’s crop will include (assuming all goes well) broccoli, kale, spinach, carrots, lettuce, tomatoes, herbs, squash, green beans, sugar-snap peas, zucchini, strawberries and sweet potatoes.
I continued my war against the briar jungle a few weekends ago by clearing a large area around our creek, which runs between the front and back pastures you see in the picture below. Before my two days of hacking away, we couldn’t see the back pasture from where I took this picture. That’s how thick the jungle was.
I also learned the value of a good helmet that weekend. I cut through a vine as thick as my wrist that had wrapped itself around one of the trees. Turns out that tree had a dead limb that was held in place by the vine — as I discovered when the limb fell and delivered what would probably have been a knockout blow to an unprotected head. The helmet absorbed much of the impact, and all I did was stagger like a drunk for a moment before recovering.
I had originally planned to clear the jungle at the back of our property as well, but I was overcome with a dose of realism. I work full-time, I’ve got a roast to write and produce before the low-carb cruise in just six more weeks, and clearing another acre or so of jungle could have easily occupied all my weekends. So I went looking on Craigslist and noticed an ad titled Reclaim Your Jungle.
The crew that did the reclaiming used an impressive machine that basically sucks weeds, bushes, briar patches and small trees into the front and grinds them into chips. In a matter of hours, they cleared an area that would have taken me lord-only-knows-how-many days with my rotating saw. It was money well spent.
The two areas you see behind our back-yard fence in the pictures below were briar jungles before. We couldn’t see much of anything past the fence. Now we can see all the way to the hills behind our property.
Shortly after that area was cleared, I looked out the window one day and saw this: deer wandering down from the hills. We counted six of them. They’ve probably been visiting that area regularly, but we couldn’t see them before.
With the last of the briar jungle gone, I was able to spend part of this weekend doing tasks more appropriate for my tools, such as tackling the dead tree along our driveway.
That’s the tree that once dumped a big, heavy branch onto a spot where Sara had been standing just moments before. We told the girls not to play near the thing anymore until I could cut down the remaining branches.
I don’t plan to cut down the remaining stump. It’s not dangerous, and it’s right in the middle of an approach to one of my disc-golf baskets. Jimmy Moore demonstrated a tendency to hit that tree during our rounds, so I want to leave at least part of it in place.
The limbs I cut down are already dry enough to burn, so we’ll be chopping those up for the wood stove.
Speaking of the wood stove, I heard something making noise inside the stovepipe this morning. Chareva opened the top of the stove to take a peek — I of course was looking for a weapon in case a small badger jumped out and attacked her. Turns out a bird had made its way into the stove.
It sat there calmly for a moment (long enough for a picture), then suddenly panicked and began to fly around the room. This caused the girls to scream — which to a small bird sounds like “we’re going to catch you and eat you,” so it flew around the room even more desperately. After attempting several times to snag the bird with a fishing net (as I did my part by capturing the effort on video), Chareva finally opened a window and the bird escaped to freedom.
One of the silliest arguments against eating meat offered by vegan zealots is that cattle cause global warming. Their argument boils down to two (incorrect or meaningless) points:
1. Trees are cut down to produce the crops required to feed cattle.
2. Cow farts add so much methane to the atmosphere, the greenhouse effect is amplified.
Trees may indeed be cut down to produce crops, but of course vegans consume crops – where do they think their whole-wheat pastas and soybean burgers come from, anyway? As Lierre Keith argued so eloquently in The Vegetarian Myth, it’s monocrop farming that’s damaging the environment, and vegetarians regularly consume the products of monocrop farming: corn, wheat, soybeans, etc.
I once responded to a vegetrollian who accused me of ruining the planet with my carnivorous diet by spelling out two scenarios:
1. A local farmer raises cattle on grass. During their lives, the cattle produce new topsoil by pooping on the ground. They require no fertilizer to grow, and they fertilize the soil naturally. When it’s time to turn the cattle into burgers and steaks, they’re driven a short distance to a local slaughterhouse, then the meat is driven a short distance to a local store, where I buy some of it and take it home to my freezer.
2. A farmer somewhere in Iowa grows soybeans, which requires massive amounts of fertilizers made from oil shipped in from the Middle East. The soybeans also require pesticides. The fertilizers and pesticides run off into local streams and rivers, poisoning the water and killing the marine life. The soybeans are then piled onto a gas-guzzling truck and shipped a long distance to an Archer Daniels Midland plant, where they’re processed into soy burgers. The soy burgers are then placed on another gas-guzzling truck and shipped to a grocery store in California, where our vegan buys them and convinces himself he’s saving the planet by eating them.
The vegetrollian never responded to my two scenarios.
The cow-fart issue is, of course, simply ridiculous. In response to yet another vegetrollian who raised that issue, I mentioned two points:
1. The Great Plains were once home to millions of buffalo, yet their methane production somehow failed to push the planet into a permanent warming cycle.
2. Given that vegetarians live on grains and beans, they’re probably major methane producers themselves. I certainly was during my vegetarian days … although it never occurred to me that I might be warming the planet.
Once again, no response from the vegetrollian.
As illogical as these beliefs are (especially the cow-fart issue), I’m not surprised that so many vegans have adopted them. As I’ve said before, many vegans are akin to religious zealots, and their beliefs are essentially religious. Raising cattle for the purpose of eating them is evil, so there must be evil consequences. The only problem is that those beliefs don’t hold up to science.
In the past environmentalists, from Lord Stern to Sir Paul McCartney, have urged people to stop eating meat because the methane produced by cattle causes global warming.
Sir Paul has written some fantastic songs, so enjoy those. Just don’t take his advice on diet.
However a new study found that cattle grazed on the grasslands of China actually reduce another greenhouse gas, nitrous oxide.
Authors of the paper, published in Nature, say the research does not mean that producing livestock to eat is good for the environment in all countries. However in certain circumstances, it can be better for global warming to let animals graze on grassland.
I’d say it’s a lot better for the planet to let animals graze on grassland. More on that later.
Klaus Butterbach-Bahl, of the Karlsruhe Institute of Technology in Germany, carried out the study in Inner Mongolia in China. He found that grassland produced more nitrous oxide during the spring thaw when sheep or cattle have not been grazing. This is because the greenhouse gas, also known as laughing gas, is released by microbes in the soil. When the grass is long snow settles keeping the microbes warm and providing water, however when the grass is cut short by animals the ground freezes and the microbes die. Related Articles
Dr Butterbach-Bahl said the study overturned assumptions about grazing goats and cattle.
“It’s been generally assumed that if you increase livestock numbers you get a rise in emissions of nitrous oxide. This is not the case,” he said.
Plant-based diets are generally seen as healthy – but they are not necessarily the healthiest diets for the environment, according to new French research.
The study, published in the American Journal of Clinical Nutrition, examined the nutritional value of the self-reported diets of nearly 2,000 French adults and compared dietary composition with estimates of greenhouse gas (GHG) emissions generated by the ingredients’ production.
Per 100 grams, the researchers found that animal products like meat, poultry, dairy, fish and eggs were indeed associated with much higher GHG emissions than fruits, vegetables and starchy foods. However, despite containing larger amounts of plant-based foods, diets of the highest nutritional quality were not necessarily the lowest in GHG emissions.
Due to ease of transportation and storage, and relative lack of waste, the least healthy foods, like sweets and salted snacks, were associated with some of the lowest emissions on an energy basis.
The researchers used a database to estimate GHG emissions per 100 grams of each food for the 400 most commonly consumed foods within the sample population. But when they looked at what people ate to meet their energy needs, they found the ‘healthiest’ diets – defined as those high in fruit, vegetables and fish – were associated with about the same level of emissions as the least healthy diets.
They explained that it was necessary to eat far more low-energy food in order to meet daily energy needs.
“Altogether, our results therefore seem to contradict the widely accepted view that diets that are good for health are also good for the planet,” they wrote.
I disagree with their belief that plant-based diets are the healthiest, but you get the idea: 100 grams of broccoli may require less energy to produce than 100 grams of chicken, but the 100 grams of chicken will provide a lot more energy. (Good luck eating enough broccoli to feel full.)
The researchers noted that red meat requires the most energy to produce and therefore has the greatest impact on the environment. Well, that depends on how it’s raised, doesn’t it? There’s a lot more to environmental impact that just energy use. Below I’ve embedded a TED talk that several readers recommended. Look at what this scientist (who has enough integrity to admit his previous beliefs were wrong) has to say about the effects of livestock on the planet:
I recommended that speech to yet another vegetrollian who showed up on the blog this week to lecture me about how eating meat will ruin the planet. (She also assured me she’s a “happy vegan,” then expressed her hope that John Nicholson, author of The Meat Fix, dies of a coronary soon. Yeah, that’s the kind of wish a happy person makes.)
No reply from the vegetrollian on the TED talk so far.