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USF professor discusses cholesterol, saturated fat and obesity myths

TAMPA, Fla. -- Food and drug companies, as well as the government, have misled Americans to believe that a diet high in cholesterol and fat leads to heart disease and obesity, according to a University of South Florida researcher.

David Diamond, a neuroscientist in the Departments of Psychology, Molecular Pharmacology and Physiology, and a career scientist at the Tampa VA Hospital, recently presented his findings--backed by more than a hundred years of scientific evidence--at a lecture hosted by the USF College of Arts and Sciences at the University Club in downtown Tampa. The lecture is available on iTunes U for free.

Diamond said there are two myths which have pervaded our society: consumption of food high in fat and cholesterol cause heart disease, and individuals will live longer if they lower their serum cholesterol through the use of medication.

“Americans are in a state of confusion,” Diamond said. “We have been led to fear foods high in cholesterol, such as eggs and beef, but the real culprit in causing heart disease, is simple carbohydrates, obtained from potatoes and refined sugar.”

According to Diamond, when an individual consumes sugar, the sugar attaches to protein molecules, which interferes with their functioning. Those abnormal protein molecules become incorporated into arterial walls, which contribute to the arteries becoming stiff. When an individual’s blood pressure rises rapidly, as occurs during stress, a tear can develop in the arterial wall. Bacteria enter the damaged artery and cause an infection. The body’s immune system sends white blood cells and LDL cholesterol, the so-called “bad cholesterol,” to the rescue to kill the bacteria.

“Cholesterol doesn’t cause the damage,” Diamond said. “It is, in fact, the spackle that helps arteries to be repaired.”

Diamond started studying cholesterol and heart disease when he turned 50, after he discovered his blood was “full of fat” and he was gaining weight. His doctor said he needed to take medication to lower his sky-high cholesterol and triglyceride levels, but Diamond decided to do some research first.

While researching heart disease and obesity, Diamond found a book by William Banting which was written in 1864. The book described how Banting, who suffered from obesity and poor health, used a low carbohydrate diet to lose weight and to improve his health. Diamond said Banting reported that he lost more than 40 pounds and lived into his 80s.

Fast-forward to the 20th century, Robert Atkins wrote a book on the benefits of a low carb diet in 1972. Diamond said the Atkins diet is quite similar to the diet described by Banting in 1864. Diamond further emphasized that he has found more than 150 years of research which has shown that a diet consisting of foods high in fat, such as meat and butter, but very low in carbohydrates, has long been shown to be an effective strategy to lose weight and to improve health.

Diamond said he found convincing research that has shown it is the carbohydrates (sugar) in your food that raises cholesterol and triglyceride levels, not the fat.

“Ultimately it is the high levels of sugar in your blood that can kill you,” Diamond said.

In 2007, against his doctor’s wishes, Diamond changed from his diet high in carbohydrates to follow guidelines developed by Banting and Atkins. His new diet consisted of 70 percent fat, 20 percent protein and 10 percent carbohydrates. He began eating eggs, butter, beef, roasted chicken with the skin, full fat cheese, coconut, dark chocolate, nuts and vegetables, such as broccoli. He allowed himself only small amounts of fruit, bread, potatoes and no refined sugar.

Diamond said his results were shocking -- his weight dropped more than 20 pounds and his triglycerides dropped from 800 (which was dangerously high) to 160, which was closer to a healthy level. His cholesterol levels also declined toward healthy levels on a diet of foods high in fat and cholesterol.

Diamond said current food recommendations have led to what he calls “fat-phobia.” The fear of eating fat has caused people to turn to high carbohydrate sources of food, resulting in excess consumption of sugar, which has contributed to the dramatic increase in obesity in recent decades.

Diamond then explained the origin of “fat-phobia.” In the 1950s, America was overwhelmed with the fear of heart disease. According to Diamond, one scientist, Ancel Keys, said Americans were having so many heart attacks because they were eating too much fat. Keys produced a now infamous graph depicting that the amount of fat in the diet predicted the extent of heart disease in countries around the world. However, Diamond revealed that Keys’ findings were fraudulent; Keys had created the association between fat and heart disease by picking data that made it appear as if there was an association between fat in the diet and heart disease.

Although other scientists at the time tried to show that Keys had deceived the public, the damage had been done. From that point on Americans were told to follow a low fat diet restricted in animal-derived food.

Diamond quoted one of the top cardiovascular researchers of the 20th century, Dr. George Mann, who said Americans have been “misled by the greatest scientific deception of our times -- the notion that consumption of animal fat causes heart disease.”

Diamond said the obesity epidemic was fueled by governmental guidelines developed in the 1970s which informed the public that eating foods low in fat was part of a healthy lifestyle. This incorrect belief led to the Food Pyramid, which recommended 6-11 servings of bread and grains per day. According to Diamond, the USDA food pyramid has been a recipe for obesity.

To add to the misrepresentation of cholesterol, Diamond said the National Cholesterol Education Program (NCEP) established a high cholesterol level at 240, which is far lower than necessary for individuals to consider taking cholesterol lowering medication.

Diamond found that most of the members of the NCEP were provided financial support from drug companies that benefited from the guidelines. Diamond asserted that this was a conflict of interest which was not revealed to the American public.

“When they [the NCEP] lowered the guidelines for safe cholesterol levels, they added 20 million Americans to the list of people who needed to have statins [cholesterol-lowering drugs] prescribed,” Diamond said. He also noted that experts in the field of cardiovascular research have disputed the NCEP guidelines for using statins to lower cholesterol.

Statins generate a vast amount of income for drug companies, according to Diamond. Lipitor, the most common statin, generates more than $10 billion per year.

He said that contrary to popular opinion, there is little evidence that people who take statins after having a heart attack will live significantly longer than those who do not take statins. And the adverse side effects of statins are more extensive than most people are aware of, including erectile dysfunction, type 2 diabetes, renal failure, liver dysfunction and cancer.

“Elevated rates of cancer have been reported in people on statins and, in general, in people with low cholesterol,” Diamond said.

In 2004, top experts in cardiovascular research in the U.S. and U.K. sent a letter to the National Institutes of Health (NIH) and Congress stating that the NCEP’s guidelines were inaccurate. The letter requested that the NIH develop new cholesterol guidelines which should be established by scientists not paid by drug companies. The request was denied by the NIH.

Diamond said the public needs to educate themselves. In his talk he identified numerous science writers and scientists who inspired him to learn the real science behind the fat and cholesterol myths. Diamond said he has learned that cholesterol has been considered a villain, when in fact, it is a misunderstood hero.

Download Diamond's PowerPoint presentation


Note to media: To schedule an interview with David Diamond, please contact Michele Dye, communications and marketing director for the USF College of Arts and Sciences, at

Filed under:Arts and Sciences Research School of Social Sciences Psychology  
Author: Melissa Russell and Nicole Nemeth