Low Carb in the News
The value and healthfulness of low carb is making the news more and more
Here, we'll be sharing the latest with you!
"Eating Low-Carb Meals After Exercise Increases Insulin Sensitivity"
A university study says that aerobic exercise, a known means of increasing insulin sensitivity, is most effective if the meals following it are low in carbohydrates. The study also revealed that consuming a low-calorie meal after exercising does not increase insulin sensitivity any better than eating a low-carb meal after a workout. In addition, it found that the beneficial effects of exercise are immediate and do not build up over time or last very long. Improvements in metabolism, including insulin sensitivity and lowered blood pressure, occur directly as a result of the latest exercise session, but taper off within hours or days. There is no "storing up" the benefits of exercise.
The study, which appears in the online edition of the Journal of Applied Physiology, was conducted by the University of Michigan. It looked at the effects of post-exercise diet on nine sedentary men, all healthy and in their late 20s. The men, who fasted beforehand, participated in four different study sessions, each lasting almost 30 hours.
The sessions differed in terms of what the men ate after exercising (or not exercising) on a treadmill and stationary bicycle:
* In a control session, the men did not exercise and ate meals that matched their daily calorie expenditure (approximately 12 calories per pound of weight).
* In another session, the men did 90 minutes of moderate exercise, followed by a meal that matched the calories they had just expended. The meal had balanced amounts of protein, fat, and carbohydrates.
* In a third session, the men exercised at moderate intensity for 90 minutes, then ate a meal with enough calories to match their energy expenditure, but with relatively low carbohydrate content. In this case, the amount of carbohydrate was 200 grams, less than half the carbs in the balanced meal.
* In a fourth session, the men exercised for 90 minutes at moderate intensity, then ate a low-calorie meal (about one-third fewer calories than the other two meals) that did not have enough calories to match what they had expended in exercise. This meal had a relatively high carbohydrate content.
The participants experienced increased insulin sensitivity after each of the three exercise sessions. However, the low-carb meals produced "significantly more" insulin sensitivity. That finding, said the researchers, indicates that even without dieting or losing weight, sedentary people who exercise and then eat a low-carb meal can gain an immediate metabolic benefit.
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"New Favorable Low Carb Study: Low-Carb Diet Burns More Liver Fat "
DALLAS—People on low-carbohydrate diets are more dependent on the oxidation of fat in the liver for energy than those on a low-calorie diet, according to a study from researchers at UT Southwestern Medical Center.
The findings, published in the journal Hepatology,could have implications for treating obesity and related diseases such as diabetes, insulin resistance and nonalcoholic fatty liver disease,said Jeffrey Browning, MD, assistant professor in the UT Southwestern Advanced Imaging Research Center and of internal medicine at the medical center.
"Instead of looking at drugs to combat obesity and the diseases that stem from it, maybe optimizing diet not only can manage and treat these diseases, but also prevent them," said Browing,the study’s lead author.
The study was not designed to determine which diet was more effective for losing weight; however, the average weight loss for the low-calorie dieters was about 5 pounds after two weeks, while the low-carbohydrate dieters lost an average of 9.5 pounds.
To determine how diet affects glucose production and utilization in the liver, researchers randomly assigned 14 obese or overweight adults to either a low-carbohydrate or low-calorie diet and monitored seven lean subjects on a regular diet. After two weeks, researchers used advanced imaging techniques to analyze the different methods the subjects used to make glucose.
Researchers found that participants on a low-carbohydrate diet produced more glucose from lactate or amino acids than those on a low-calorie diet.
"Understanding how the liver makes glucose under different dietary conditions may help us better regulate metabolic disorders with diet," Browning said.
The different diets produced other differences in glucose metabolism.Low-calorie dieters got about 40 percent of their glucose from glycogen, which comes from ingested carbohydrates, and is stored in the liver until the body needs it. Low-carb dieters got only 20 percent of their glucose from glycogen. Instead of dipping into their reserve of glycogen, the subjects burned liver fat for energy.
The findings are significant because the accumulation of excess fat in the liver—primarily a form of fat called triglycerides—can result in nonalcoholic fatty liver disease (NAFLD).
Browning previously has shown NAFLD may affect as many as one-third of U.S. adults. The disease is associated with metabolic disorders such as insulin resistance,diabetes and obesity, and it can lead to liver inflammation, cirrhosis and liver cancer.
* Sources:UT Southwestern Medical Center: Low-carbohydrate diet burns more excess liver fat than low-calorie diet, study finds
"Low Carb Connoisseur Announces Website Relaunch"
"Good Calories, Bad Calories"
Review from Amazon:
"Gary Taubes's Good Calories, Bad Calories is easily the most important book on diet and health to be published in the past one hundred years. It is clear, fast-paced and exciting to read, rigorous, authoritative, and a beacon of hope for all those who struggle with problems of weight regulation and general health--as who does not? If Taubes were a scientist rather than a gifted, resourceful science journalist, he would deserve and receive the Nobel Prize in Medicine."
-Richard Rhodes, winner of the Pulitzer Prize
"If Taubes were inclined to sensationalism, he might have titled this book "The Great Low-Fat Diet Hoax." Instead, he tackles the subject with the seriousness and scientific insight it deserves, building a devastating case against the low-fat, high-carb way of life endorsed by so many nutrition experts in recent years. With diabetes and heart disease at stake as well as obesity, those "experts" owe us an abject apology."
In this groundbreaking book, the result of seven years of research in every science connected with the impact of nutrition on health, award-winning science writer Gary Taubes shows us that almost everything we believe about the nature of a healthy diet is wrong.
For decades we have been taught that fat is bad for us, carbohydrates better, and that the key to a healthy weight is eating less and exercising more. Yet with more and more people acting on this advice, we have seen unprecedented epidemics of obesity and diabetes. Taubes argues persuasively that the problem lies in refined carbohydrates (white flour, sugar, easily digested starches)"via their dramatic effect on insulin, the hormone that regulates fat accumulation"and that the key to good health is the kind of calories we take in, not the number. There are good calories, and bad ones.
Taubes traces how the common assumption that carbohydrates are fattening was abandoned in the 1960s when fat and cholesterol were blamed for heart disease and then "wrongly"were seen as the causes of a host of other maladies, including cancer. He shows us how these unproven hypotheses were emphatically embraced by authorities in nutrition, public health, and clinical medicine, in spite of how well-conceived clinical trials have consistently refuted them. He also documents the dietary trials of carbohydrate-restriction, which consistently show that the fewer carbohydrates we consume, the leaner we will be.
With precise references to the most significant existing clinical studies, he convinces us that there is no compelling scientific evidence demonstrating that saturated fat and cholesterol cause heart disease, that salt causes high blood pressure, and that fiber is a necessary part of a healthy diet. Based on the evidence that does exist, he leads us to conclude that the only healthy way to lose weight and remain lean is to eat fewer carbohydrates or to change the type of the carbohydrates we do eat, and, for some of us, perhaps to eat virtually none at all.
Good Calories, Bad Calories is a tour de force of scientific investigation"certain to redefine the ongoing debate about the foods we eat and their effects on our health.
Many of you remember a young science author named Gary Taubes, who
endeared himself to low carbers everywhere last year when he penned
an article called The
Soft Science of Dietary Fat for Science magazine's March 30, 2001 issue (here's
He took a serious look at the dubious "science" that says fat is bad.
He received a 2001 Science in Society Journalism Award for this amazing article.
This week he renewed his hero-status with me (and countless others) when his
if It's All Been a Big Fat Lie? was published, continuing his exploration of
the dietary wrongs of the U.S. (and elsewhere.) Below, see the beginning of
this great article, and then click on the link above to read the article in its
"What if It's All Been a Big Fat Lie?"
If the members of the American medical establishment were to have a collective find-yourself-standing-naked-in-Times-Square-type nightmare, this might be it. They spend 30 years ridiculing Robert Atkins, author of the phenomenally-best-selling Dr. Atkins' Diet Revolution and Dr. Atkins' New Diet Revolution, accusing the Manhattan doctor of quackery and fraud, only to discover that the unrepentant Atkins was right all along. Or maybe it's this: they find that their very own dietary recommendations "eat less fat and more carbohydrates" are the cause of the rampaging epidemic of obesity in America. Or, just possibly this: they find out both of the above are true.
When Atkins first published his "Diet Revolution" in 1972, Americans were just coming to terms with the proposition that fat "particularly the saturated fat of meat and dairy products" was the primary nutritional evil in the American diet. Atkins managed to sell millions of copies of a book promising that we would lose weight eating steak, eggs and butter to our heart's desire, because it was the carbohydrates, the pasta, rice, bagels and sugar, that caused obesity and even heart disease. Fat, he said, was harmless.
Atkins allowed his readers to eat "truly luxurious foods without limit," as he put it, "lobster with butter sauce, steak with bearnaise sauce . . . bacon cheeseburgers," but allowed no starches or refined carbohydrates, which means no sugars or anything made from flour. Atkins banned even fruit juices, and permitted only a modicum of vegetables, although the latter were negotiable as the diet progressed.
Atkins was by no means the first to get rich pushing a high-fat diet that restricted carbohydrates, but he popularized it to an extent that the American Medical Association considered it a potential threat to our health. The A.M.A. attacked Atkins's diet as a "bizarre regimen" that advocated "an unlimited intake of saturated fats and cholesterol-rich foods," and Atkins even had to defend his diet in Congressional hearings.
Thirty years later, America has become weirdly polarized on the subject of weight.
On the one hand, we've been told with almost religious certainty by everyone from the surgeon general on down, and we have come to believe with almost religious
certainty, that obesity is caused by the excessive consumption of fat, and that if we eat less fat we will lose weight and live longer. On the other, we have
the ever-resilient message of Atkins and decades' worth of best-selling diet books, including "The Zone," "Sugar Busters" and "Protein Power" to name a few. All push some variation of what scientists would call the alternative
hypothesis: it's not the fat that makes us fat, but the carbohydrates, and if we eat less carbohydrates we will lose weight and live longer.
The perversity of this alternative hypothesis is that it identifies the cause of obesity as precisely those refined carbohydrates at the base of the famous Food Guide Pyramid "the pasta, rice and bread" that we are told should be the staple of our healthy low-fat diet, and then on the sugar or corn syrup in the soft drinks, fruit juices and sports drinks that we have taken to consuming in quantity if for no other reason than that they are fat free and so appear intrinsically healthy. While the low-fat-is-good-health dogma represents reality as we have come to know it, and the government has spent hundreds of millions of dollars in research trying to prove its worth, the low-carbohydrate message has been relegated to the realm of unscientific fantasy.
Over the past five years, however, there has been a subtle shift in the scientific consensus. It used to be that even considering the possibility of the alternative hypothesis, let alone researching it, was tantamount to quackery by association. Now a small but growing minority of establishment researchers have come to take seriously what the low-carb-diet doctors have been saying all along. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health, may be the most visible proponent of testing this heretic hypothesis. Willett is the de facto spokesman of the longest-running, most comprehensive diet and health studies ever performed, which have already cost upward of $100 million and include data on nearly 300,000 individuals. Those data, says Willett, clearly contradict the low-fat-is-good-health message "and the idea that all fat is bad for you; the exclusive focus on adverse effects of fat may have contributed to the obesity epidemic."
Click here to read full article.