|Help for 'Diet War' Veterans|
Panel Weighs In on 'Diet, Fat & Cholesterol'
By Carla Garnett
Photos by Ernie Branson
On the Front Page...
If you've ever worried about how much fat to eat, whether you should diet or the difference between "good" and "bad" cholesterol, then the recent seminar, "Promoting Healthy Lives: Diet, Fat & Cholesterol," was tailormade for you. Sponsored by the Office of Research on Women's Health as part of its 2001-2002 seminar series, the event featured three experts to present the facts, and perhaps more importantly refute the innumerable myths that swirl perpetually around these three topics.
"Controversy on how much fat we should eat and what type has been debated since back in the 1950s," began Dr. Frank Sacks, a professor of cardiovascular disease prevention at Harvard School of Public Health who also runs a clinic in hyperlipidemia at Brigham and Women's Hospital. "Not every issue has been solved and we're far from having it nailed down yet."
Questions remain, he continued, concerning the ideal amount of fat in the diet to help prevent cardiovascular disease, whether low-fat or moderate-fat diets are better for healthy weight loss, and how physical activity factors in the equation. What is clear, he said, is that these questions and many others must be resolved in order to reduce the burden of such disorders as heart attack, stroke, diabetes and obesity.
The Truth About Cholesterol
Sacks also tackled the complex issue of "good" and "bad" cholesterol. Cholesterol, he explained, is an essential molecule produced naturally by the liver. The molecule travels via lipoproteins through the bloodstream. Harmful lipoproteins LDL and VLDL popularly referred to as the "bad cholesterol" take cholesterol to unhealthy places in the body. HDL the so-called "good cholesterol" is beneficial because it transports cholesterol out of the body. The liver makes enough cholesterol so that we never need to eat any. In fact, Sacks said, problems begin when we overload the liver with cholesterol we consume.
"Cholesterol is one molecule that can be carried in different directions," he said. "We're worried about cholesterol being delivered by LDL and VLDL to the artery wall and thereby leading to atherosclerosis. HDL is protective. It reflects cholesterol being carried out of the artery wall, reversing atherosclerosis."
Guidelines for bad cholesterol amounts in the blood for adults have been established by NHLBI's National Cholesterol Education Program. In general, LDL below 100 is optimum. High HDL a reading at 60 or above is considered to be a health benefit.
Sacks said researchers have developed a formula called the "Metabolic Syndrome" to determine risk for such problems as hypertension and diabetes. Data in five categories abdominal obesity (waist circumference), triglycerides (fat), HDL, blood pressure and fasting glucose are collected; undesirable levels in any three of the five constitute the syndrome. Prevalence of the syndrome which Sacks called "a combination of age, genetic susceptibility and our habits" has increased considerably worldwide over the past 10 years. An estimated 40 percent of the U.S. population has the syndrome that he said "is increasing because of things we do to ourselves. It represents a real challenge for us to solve."
Sacks concluded by discussing how the formulas and measurements can be used to achieve the ultimate goal preventing disease. He said despite developing an ideal equation, several obstacles block the goal: poor communication with patients, economics of healthcare, heavy marketing of unhealthy foods and incentives for gluttony.
Optimize Mind as Well as Body
On the issue of dieting, Dr. Gary Foster, clinical director of the Weight and Eating Disorders Program at the University of Pennsylvania School of Medicine, proposed a societal mind change in body image perception.
"What's relevant here is how we think," he said. "Obesity has become somewhat of a moral issue. There's this moral connotation associated with eating. Some people even talk about cheating on their diets. It's part of the vernacular. How do you equate a 220-calorie decision with your morality? Clean up that cognitive ecology. Some people see it as a cosmetic issue. Professionals see it as a health issue. It's certainly not accurate or effective to view obesity as some lack of will power, or to see obese people as weak-willed, lazy or undisciplined. The data just don't support that. The biggest challenge we face is: How do we get ourselves at peace with not weighing what the fashion models weigh?"
How the nation arrived at this critical health juncture is simple, Foster said, showing slides of ever-increasing portion sizes of popular foods. In 1950, the standard soft drink serving was 8 oz. In 1970, the 12-oz. can came along. These days, a 20-oz. bottle is popular, not to mention the 32-oz. and 64-oz. sizes available at almost every venue. "What's happened is that we eat more and move less," he explained.
Sharing a term "obesogenic" that explains society's role, Foster said, "The environment is quite toxic" and exacerbating the problem is that "we place a premium on energy-saving devices," such as escalators and remote controls, which reduce opportunities to burn off excess calories. "We don't have to give up these things," he said, "but we do have to realize that there are consequences."
Given the culture's obsession with unreasonably small body images, Foster suggested that individuals adjust their interiors before addressing their posteriors.
"You probably can't lose as much weight as you want," he concluded. "Behavior makes a difference, but biology matters too. To diet or not to diet? My suggestion is to make small changes that last and avoid dramatic changes that don't last. Think about health, not just about weight. This has to be a positive process something you're doing for yourself and not against yourself. If you're punishing yourself for being bad by going on this restrictive diet, it's not going to work. And, finally, take your life off hold. Live your life now. If you take nothing else away from this talk, take this: do not make your weight part of your self-esteem."
Fat: Where It's At, Where It's Going
"Okay, so how many of you are completely confused about what to eat and what you are supposed to do for your bodies?" asked Dr. Pamela Peeke, only half-joking but correctly reading the many perplexed faces in the audience. "How many of you are veterans of the diet wars?" she pressed. As several attendees hesitantly raised their hands, a grinning Peeke quipped, "All of the rest of you are liars!"
A former NIH senior research fellow and an internationally recognized expert on nutrition and stress, Peeke opened her presentation with a humorous quote from Mark Twain: "'The only way to keep your health is to eat what you don't want, drink what you don't like and do what you'd rather not.' What we'd like to do is give a few data bites so that you might go home and realize that you don't have to have this kind of an attitude," she explained. "What you want to do to optimize your body and your mind at the same time is quite doable. It's just that you don't want to turn yourself into a science fair project."
Delving into her lecture, "Facts About Fat," Peeke said the key to understanding the true nature of fat is knowing what kind to eat, and where it ends up on your body. "We all realize after quite a bit of media hype that this issue of 'fat as bad' is just ridiculous...The fact that we're eating potentially too much of certain fats, and the forms of fat we're eating and the way those fats are processed that's really where the topic should begin."
The prevalence of obesity in the U.S. is increasing, she lamented, and the U.S. is "probably number one in the world now." According to the Centers for Disease Control and Prevention, for the first time in history, there are more overweight and obese people in the nation than people of normal weight.
"The saddest part about this is what is happening to the children," she said. "One out of four is quite overweight and obesity is rising, as are the consequences. Children with type 2 diabetes are much more prevalent. This used to be an old person's disease (that means over 50, she said with a wink). We're now diagnosing this at ages 7, 10, 15. The incidence of type 2 diabetes between ages 30 and 40 has increased 70 percent."
Peeke mentioned that while researchers were heartened several years ago when a gene for obesity was identified, they also realize that genes are not solely responsible for obesity.
"In certain families, there is no question there is a strong predisposition," she acknowledged, "but what I like to say is 'genetics may load the gun, but environment pulls the trigger.'"
Supporting Foster's conclusion that today's culture offers little help, Peeke noted that in the U.S., 41 percent of food dollars are spent outside the home. In the 1950s, Americans spent only 19 percent of their food dollars outside the home. These days, she said, 34 percent of our calories are consumed outside the home; in 1977, only 18 percent.
The solution, Peeke advised, is for individuals to take control of what they eat. Fat has an important role in digestion and production of energy for the body, she said, but it's the type of fat that makes all the difference.
To see a broadcast of the full seminar via computer, visit http://videocast.nih.gov.
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