Wednesday, November 24, 2010

Low Fat Finally Gets the Boot.

Bonnie and Steve:
In one of the biggest missteps of the last forty years, public health educators convinced most Americans that eating low-fat foods was good for their health. After seeing our population become fatter than any time in its history, FINALLY, researchers are putting that catastrophic notion to bed.

The chief proponent of this dietary faux pas, American Dietetic Association (ADA), finally swallowed their pride and admitted at their annual conference there is strong evidence that replacing fat with carbohydrates could be harmful to health. Recommendations to reduce saturated fat intake are largely based on the notion that high levels increase risk of cardiovascular disease, but unless saturated fat is replaced with other fats, many studies have suggested that fat reduction could increase risk of heart disease.

At the conference, four leading experts presented evidence suggesting that low fat diets may be less healthy than those containing at least a moderate amount of fat. In particular, all four agreed that replacing saturated fat with carbohydrates – as has been widely recommended in the United States – is likely to raise the risk of cardiovascular disease. "The emphasis should be on displacing saturated fat and trans fat with unsaturated fat because that is where the data is,” one researcher said. “…‘Displace saturated fat with polyunsaturated fat’ was simplified to ‘low fat’. Then ‘low fat’ became ‘low calorie’. The low fat message is still very pervasive, especially in the lay press.”

Chair of the Harvard School of Public Health’s nutrition department Dr. Walter Willett took it even further. “If anything, the literature shows a slight advantage of the high fat diet,” he said. “The focus on fat in dietary guidelines has been a massive distraction…We should remove total fat from nutrition facts panels on the back of packs.” He added that while the pervasive dietary guidance given to consumers has been to eat fats sparingly, to load up on starch and eat non-fat products, “the food industry quickly realized sugar was cheaper than fat and laughed all the way to the bank.” “It was really the type of fat that was important,” he said. “If you replaced saturated fat with polyunsaturated fat there was a reduction of risk.”

“The biggest problem in America at the moment is eating behavior,”
Professor of public health and professor of epidemiology at the University of Pittsburgh’s Graduate School of Public Health, Dr. Lewis Kuller said. “…Eating is a social pleasure and not a therapeutic challenge. We have done a great job of confusing the public.”

Assistant professor of medicine at Harvard Medical School Dr. Mozaffarian agreed with the other speakers about a lack of evidence linking total fat consumption and cardiovascular disease risk. High levels of low density lipoprotein (LDL cholesterol) and high triglyceride levels have both been linked to increased risk of cardiovascular disease, but Mozaffarian said there has often been overreliance on single biomarkers in drawing conclusions about fats’ impact on heart health, “even one as hallowed as LDL cholesterol”. “Overall dietary quality is very important for cardiovascular risk,” he said. “Saturated fats may raise LDL cholesterol but increasing levels of all fats lowers triglycerides…You can’t look at data across countries and draw conclusions. Nor can you look at animal studies or a single biomarker and draw conclusions from that.”

Concluding the discussion, Dr. Lichtenstein warned against focusing on single nutrients for disease risk reduction. She said: “We need to stop focusing on individual dietary components because when one goes down, another goes up.”

Don't these comments sound awfully similar to what somebody you know has been saying for a long, long time now? This next piece adds even more fascinating fuel to the fire.

Reducing Carbs the key to Quality Longevity?

Excerpts from a recent article in The Daily Mail

The problem is that this longevity does not mean a healthier life, thanks to chronic diseases such as diabetes and arthritis. But now a U.S. geneticist is thought to have discovered a secret to a long life, full of health and energy. And the answer might be as simple as cutting down on carbohydrates.

University of California, San Francisco Professor Cynthia Kenyon, whom many experts believe should win the Nobel Prize for her research into aging, has discovered that the carbohydrates we eat directly affect two key genes that govern youthfulness and longevity. She made her remarkable breakthrough after studying roundworms. By tweaking some of their genes she has been able to help these worms live up to six times longer than normal, as well as make them stay healthy all that time as well.

Professor Kenyon’s work has been successfully repeated in labs around the world — the genes she found controlling aging in worms do the same thing in rats and mice, probably monkeys, and there are signs they are active in humans, too. This work has revolutionized our understanding of aging. Ten years ago, scientists thought aging was probably the result of a slow decay, a sort of rusting. But Professor Kenyon has shown that it’s not about wear and tear, but instead it is controlled by genes.

At 18 days old the average roundworm is flabby, ­sluggish and wrinkled. Two days later it will probably be dead.
Professor Kenyon found that damping down the activity of just one of their genes had a dramatic effect. Instead of dying at about 20 days, the first set of mutant worms carried on living to more than 40 days. They weren’t sluggish and worn out — they behaved like youngsters. In human terms it was the equivalent of talking to someone you thought was about 30 and finding they were actually 60. With more sophisticated genetic manipulation, she now has some worms that have lived for an astonishing 144 days. An increase of that proportion would allow humans to live to 450.

Professor Kenyon found out was why ­drastically reducing calories has such a remarkable effect. She discovered that it changed the way two crucial genes behaved. It turned down the gene that controls insulin, which in turn switched on another gene, which acted like an elixir of life. We jokingly called the first gene the Grim Reaper because when it’s switched on, the lifespan is fairly short. The ­second ‘elixir’ gene seems to bring all the anti-aging benefits — its proper name is DAF 16, but it was quickly nicknamed ‘Sweet Sixteen’ because it turned the worms into teenagers. It sends out instructions to a whole range of repair and renovation genes. Your supply of natural anti­oxidants goes up, damping down damaging free radicals. The Sweet Sixteen gene also boosts compounds that make sure the skin and muscle-building ­proteins are working properly, the immune system becomes more active to fight infection and genes that are active in cancer get turned off.

Discovering the Grim Reaper gene has prompted the professor to ­dramatically alter her own diet, ­cutting right back on carbohydrates. That’s because carbs make your body produce more insulin (to mop up the extra blood sugar carbs ­produce); and more insulin means a more active Grim Reaper. So the vital second gene, the ‘elixir’ one, won’t get turned on.

To test this, last year she added a tiny amount of ­sugary glucose to the normal diet of some of her worms that had had their genes engineered so they were living much longer, healthier lives. The effect was remarkable. The sugary glucose blocked the “youthful” genes and they lost most of the health gains.

Following Kenyon’s lead, other researchers started looking for the Grim Reaper/ Sweet Sixteen combination in other animals — and of course in humans. They found it. One clue came from a small remote community of dwarves living in northern Ecuador who are cancer-free. They are missing the part of the Grim Reaper gene that controls a hormone called insulin-like growth factor. The downside is they only grow to 4ft tall because the hormone is needed for growth.
But this missing bit of the Grim Reaper gene also means they don’t develop cancer and are less likely to suffer from heart disease or obesity.

Research is at its early stage, but raised insulin triggers an increase in cholesterol production in the liver, makes the walls of blood vessels ­contract so blood pressure goes up and stimulates the release of fats called triglycerides.

Besides dietary modification, Kenyon says, another way to reduce insulin levels is to exercise, which makes you more sensitive to it, which in turn means you need less of it. It also gives another health benefit in a surprising way. Exercise actually increases the level of damaging free radicals which stimulates the body to produce more protective anti-oxidants.

Results of the Largest Study on Diet Ever Done

Researchers at the Faculty of Life Sciences (LIFE), University of Copenhagen, can now unveil the results of the world's largest diet study: If you want to lose weight, you should maintain a diet that is high in proteins with more lean meat, beans and fewer finely refined starch calories such as white bread and white rice. With this diet, most people can also eat until they are full without counting calories and without gaining weight. Finally, the extensive study concludes that the official dietary recommendations are not sufficient for preventing obesity.

The design comprised the following five diet types:
-A low-protein diet (13% of energy consumed) with a high glycemic index (GI)
-A low-protein, low-GI dietA high-protein (25% of energy consumed), low-GI diet
-A high-protein, high-GI diet
-A control group which followed the current dietary recommendations without special instructions regarding glycemic index levels
-A high-protein, low-GI diet works best A total of 938 overweight adults with a mean body mass index (BMI) of 34 kg/sq m were initially placed on an 800-kcal-per-day diet for eight weeks before the actual diet intervention was initiated.

The average weight regain among all participants was 0.5 kg, but among the participants who completed the study, those in the low-protein/high-GI group showed the poorest results with a significant weight gain of 1.67 kg. The weight regain was 0.93 kg less for participants on a high-protein diet than for those on a low-protein diet and 0.95 kg less in the groups on a low-GI diet compared to those on a high-GI diet.

The study was conducted by eight European research centers and headed by Thomas Meinert Larsen, PhD, and Professor Arne Astrup, DrMedSc and Head of Department at the Faculty of Life Sciences (LIFE) and is funded by an EU grant of EUR 14.5 million.

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