(HealthDay News) -- A natural protein might help the body rid itself of fat while suppressing appetite.
Researchers say the protein, called ciliary neurotrophic factor (CNTF), acts directly with muscles, boosting the body's fat-burning ability as it helps protect against some of the effects of obesity.
"While hormones such as leptin were initially thought to be the cure-all for weight loss, they were later found to be ineffective in obesity due to the presence of proteins which inhibit their ability to stimulate fat metabolism. Fortunately, CNTF's effects on fat burning are maintained," research leader Dr. Greg Steinberg, of the University of Melbourne in Australia, said in a prepared statement.
Reporting in this week's issue of Nature Medicine, his team found that CNTF activates an enzyme called skeletal muscle AMP kinase, which in turns boosts the body's ability to metabolize fat and sugar. The pathways activated by CNTF are similar to those activated by exercise. The findings may help in the development of new ways to reduce the risk of metabolic abnormalities associated with excess weight.
The study was funded by the Heart and Stroke Foundation of Canada, the Canadian Institutes of Health Research (CIHR), and the Canadian Diabetes Association.
Until recently, most obesity research has concentrated on the regulation of appetite by hormones such as leptin.
"Dr. Steinberg's finding is significant because this new pathway that overcomes leptin resistance opens the door to a more promising avenue for the development of a therapeutic anti-obesity agent," Dr. Diane Finegood, scientific director of the CIHR's Institute of Nutrition, Metabolism and Diabetes, said in a prepared statement.
More information
The U.S. Institute of Diabetes and Digestive and Kidney Diseases explains the health risks of being overweight.
Monday, September 25, 2006
Study Shows Liver, Kidney, and Pancreatic Cancers More Frequent in Diabetes Patients By Salynn Boyles
Study Shows Liver, Kidney, and Pancreatic Cancers More Frequent in Diabetes Patients
Reviewed By Louise Chang, MDon Monday, September 25, 2006
Sept. 25, 2006 -- Adults with diabetes may be at increased risk for developing several kinds of cancer, according to new research from Japan.
In the study, men with diabetes were found to have more liver, kidney, and pancreatic cancers than men without the disease. And women with diabetes had more stomach and liver cancers than women who didn't have diabetes.
The Japanese study presents some of the strongest evidence yet linking diabetes and cancer, but it is not yet clear if diabetes actually causes malignant disease, researchers from the National Cancer Center, Tokyo, wrote.
Diabetes Rates on the Rise
As with other industrialized countries, including the U.S., diabetes rates have skyrocketed in Japan in recent years, and they continue to rise.
Approximately 150 million people worldwide have diabetes. But that number is expected to double within the next two decades as the population ages.
"The remarkable increase in the diagnosis of diabetes in Japan in recent years may affect future trends in the incidence and type of cancer," the Japanese researchers write in the Sept. 25 issue of the Archives of Internal Medicine.
Researcher Manami Inoue, MD, PhD, and colleagues followed nearly 98,000 men and women in Japan for 9 to 13 years. Participants were between the ages of 40 and 69 when they entered the study.
At enrollment, 3,097 of the men (6.7%) and 1,571 of the women (3.1%) had diabetes or had a history of having the disease. By the end of the study's follow-up in December 2003, 3,907 men, including 366 with diabetes, and 2,555 women, including 104 with diabetes, had developed cancer.
Total cancer risk was found to be 27% higher for men with diabetes than for men without the disease. For women with diabetes, they found an increased risk for stomach and liver cancers specifically.
Among men, the risk was especially high for cancers of the liver, kidney, and pancreas.
Reviewed By Louise Chang, MDon Monday, September 25, 2006
Sept. 25, 2006 -- Adults with diabetes may be at increased risk for developing several kinds of cancer, according to new research from Japan.
In the study, men with diabetes were found to have more liver, kidney, and pancreatic cancers than men without the disease. And women with diabetes had more stomach and liver cancers than women who didn't have diabetes.
The Japanese study presents some of the strongest evidence yet linking diabetes and cancer, but it is not yet clear if diabetes actually causes malignant disease, researchers from the National Cancer Center, Tokyo, wrote.
Diabetes Rates on the Rise
As with other industrialized countries, including the U.S., diabetes rates have skyrocketed in Japan in recent years, and they continue to rise.
Approximately 150 million people worldwide have diabetes. But that number is expected to double within the next two decades as the population ages.
"The remarkable increase in the diagnosis of diabetes in Japan in recent years may affect future trends in the incidence and type of cancer," the Japanese researchers write in the Sept. 25 issue of the Archives of Internal Medicine.
Researcher Manami Inoue, MD, PhD, and colleagues followed nearly 98,000 men and women in Japan for 9 to 13 years. Participants were between the ages of 40 and 69 when they entered the study.
At enrollment, 3,097 of the men (6.7%) and 1,571 of the women (3.1%) had diabetes or had a history of having the disease. By the end of the study's follow-up in December 2003, 3,907 men, including 366 with diabetes, and 2,555 women, including 104 with diabetes, had developed cancer.
Total cancer risk was found to be 27% higher for men with diabetes than for men without the disease. For women with diabetes, they found an increased risk for stomach and liver cancers specifically.
Among men, the risk was especially high for cancers of the liver, kidney, and pancreas.
Thursday, May 11, 2006
The facts about weight loss
The Weight-Loss Industry
Looking for a quick and easy way to lose weight? You're not alone. An estimated 50 million Americans will go on diets this year. And while some will succeed in taking the weight off, very few — perhaps 5 percent — will manage to keep all of it off in the long run.
One reason for the low success rate is that many people look for quick and easy solutions to their weight problems. They find it hard to believe in this age of scientific innovations and medical miracles that an effortless weight-loss method doesn't exist.
So they succumb to quick-fix claims like 'Eat All You Want and Still Lose Weight!' or 'Melt Fat Away While You Sleep!' And they invest their hopes (and their money) in all manner of pills, potions, gadgets, and programs that hold the promise of a slimmer, happier future.
The weight-loss business is a booming industry. Americans spend an estimated $30 billion a year on all types of diet programs and products, including diet foods and drinks. Trying to sort out all of the competing claims — often misleading, unproven, or just plain false — can be confusing and costly.
This brochure is designed to give you the facts behind the claims, to help you avoid the outright scams, and to encourage you to consider thoroughly the costs and consequences of the dieting decisions you make.
The Facts About Weight Loss
Being obese can have serious health consequences. These include an increased risk of heart disease, stroke, high blood pressure, diabetes, gallstones, and some forms of cancer. Losing weight can help reduce these risks. Here are some general points to keep in mind:
Any claims that you can lose weight effortlessly are false. The only proven way to lose weight is either to reduce the number of calories you eat or to increase the number of calories you burn off through exercise. Most experts recommend a combination of both.
Very low-calorie diets are not without risk and should be pursued only under medical supervision. Unsupervised very low-calorie diets can deprive you of important nutrients and are potentially dangerous.
Fad diets rarely have any permanent effect. Sudden and radical changes in your eating patterns are difficult to sustain over time. In addition, so-called 'crash' diets often send dieters into a cycle of quick weight loss, followed by a 'rebound' weight gain once normal eating resumes, and even more difficulty reducing when the next diet is attempted.
To lose weight safely and keep it off requires long-term changes in daily eating and exercise habits. Many experts recommend a goal of losing about a pound a week. A modest reduction of 500 calories per day will achieve this goal, since a total reduction of 3,500 calories is required to lose a pound of fat. An important way to lower your calorie intake is to learn and practice healthy eating habits.
In Search of the 'Magic Bullet'
Some dieters peg their hopes on pills and capsules that promise to 'burn,' 'block,' 'flush,' or otherwise eliminate fat from the system. But science has yet to come up with a low-risk 'magic bullet' for weight loss. Some pills may help control the appetite, but they can have serious side effects. (Amphetamines, for instance, are highly addictive and can have an adverse impact on the heart and central nervous system.) Other pills are utterly worthless.
The Federal Trade Commission and a number of state Attorney General have successfully brought cases against marketers of pills claiming to absorb or burn fat. The Food and Drug Administration has banned 111 ingredients once found in over-the-counter diet products. None of these substances, which include alcohol, caffeine, dextrose, and guar gum, have proved effective in weight-loss or appetite suppression.
Beware of the following products that are touted as weight-loss wonders:
Diet patches, which are worn on the skin, have not been proven to be safe or effective. The FDA has seized millions of these products from manufacturers and promoters.
'Fat blockers' purport to physically absorb fat and mechanically interfere with the fat a person eats.
'Starch blockers' promise to block or impede starch digestion. Not only is the claim unproven, but users have complained of nausea, vomiting, diarrhea, and stomach pains.
'Magnet' diet pills allegedly 'flush fat out of the body.' The FTC has brought legal action against several marketers of these pills.
Glucomannan is advertised as the 'Weight Loss Secret That's Been in the Orient for Over 500 Years.' There is little evidence supporting this plant root's effectiveness as a weight-loss product.
Some bulk producers or fillers, such as fiber-based products, may absorb liquid and swell in the stomach, thereby reducing hunger. Some fillers, such as guar gum, can even prove harmful, causing obstructions in the intestines, stomach, or esophagus. The FDA has taken legal action against several promoters containing guar gum.
Spirulina, a species of blue-green algae, has not been proven effective for losing weight.
Phony Devices and Gadgets
Phony weight-loss devices range from those that are simply ineffective to those that are truly dangerous to your health. At minimum, they are a waste of your hard-earned money. Some of the fraudulent gadgets that have been marketed to hopeful dieters over the years include:
Electrical muscle stimulators have legitimate use in physical therapy treatment. But the FDA has taken a number of them off the market because they were promoted for weight loss and body toning. When used incorrectly, muscle stimulators can be dangerous, causing electrical shocks and burns.
'Appetite suppressing eyeglasses' are common eyeglasses with colored lenses that claim to project an image to the retina which dampens the desire to eat. There is no evidence these work.
'Magic weight-loss earrings' and devices custom-fitted to the purchaser's ear that purport to stimulate acupuncture points controlling hunger have not been proven effective.
Diet Programs
Approximately 8 million Americans a year enroll in some kind of structured weight-loss program involving liquid diets, special diet regimens, or medical or other supervision. In 1991, about 8,500 commercial diet centers were in operation across the country, many of them owned by a half-dozen or so well-known national companies.
Before you join such a program, you should know that according to published studies relatively few participants succeed in keeping off weight long-term. Recently, the FTC brought action against several companies challenging weight-loss and weight-maintenance claims. Unfortunately, some other companies continue to make overblown claims.
The FTC stopped one company from claiming its diet program caused rapid weight loss through the use of tablets that would 'burn fat' and a protein drink mix that would adjust metabolism. The FTC also took action against three major programs using doctor-supervised, very low-calorie liquid diets, and they agreed to stop making claims unless they could back them up with hard data.
Before you sign up with a diet program, you might ask these questions:
What are the health risks?
What data can you show me that proves your program actually works?
Do customers keep off the weight after they leave the diet program? ?
What are the costs for membership, weekly fees, food, supplements, maintenance, and counseling? What's the payment schedule? Are any costs covered under health insurance? Do you give refunds if I drop out?
Do you have a maintenance program? Is it part of the package or does it cost extra?
What kind of professional supervision is provided? What are the credentials of these professionals?
What are the program's requirements? Are there special menus or foods, counseling visits, or exercise plans?
Clues to Fraud
It is important for consumers to be wary of claims that sound too good to be true. When it comes to weight-loss schemes, consumers should be particularly skeptical of claims containing words and phrases like:
easy
effortless
guaranteed
miraculous
magical
breakthrough
new discovery
mysterious
exotic
secret
exclusive
ancient
Sensible Weight Maintenance Tips
Losing weight may not be effortless, but it doesn't have to be complicated. To achieve long-term results, it's best to avoid quick-fix schemes and complex regimens. Focus instead on making modest changes to your life's daily routine. A balanced, healthy diet and sensible, regular exercise are the keys to maintaining your ideal weight. Although nutrition science is constantly evolving, here are some generally-accepted guidelines for losing weight:
Consult with your doctor, a dietician, or other qualified health professional to determine your ideal healthy body weight.
Eat smaller portions and choose from a variety of foods.
Load up on foods naturally high in fiber: Fruits, vegetables, legumes, and whole grains.
Limit portions of foods high in fat: dairy products like cheese, butter, and whole milk; red meat; cakes and pastries.
Exercise at least three times a week.
U. S. Food and Drug Administration
Looking for a quick and easy way to lose weight? You're not alone. An estimated 50 million Americans will go on diets this year. And while some will succeed in taking the weight off, very few — perhaps 5 percent — will manage to keep all of it off in the long run.
One reason for the low success rate is that many people look for quick and easy solutions to their weight problems. They find it hard to believe in this age of scientific innovations and medical miracles that an effortless weight-loss method doesn't exist.
So they succumb to quick-fix claims like 'Eat All You Want and Still Lose Weight!' or 'Melt Fat Away While You Sleep!' And they invest their hopes (and their money) in all manner of pills, potions, gadgets, and programs that hold the promise of a slimmer, happier future.
The weight-loss business is a booming industry. Americans spend an estimated $30 billion a year on all types of diet programs and products, including diet foods and drinks. Trying to sort out all of the competing claims — often misleading, unproven, or just plain false — can be confusing and costly.
This brochure is designed to give you the facts behind the claims, to help you avoid the outright scams, and to encourage you to consider thoroughly the costs and consequences of the dieting decisions you make.
The Facts About Weight Loss
Being obese can have serious health consequences. These include an increased risk of heart disease, stroke, high blood pressure, diabetes, gallstones, and some forms of cancer. Losing weight can help reduce these risks. Here are some general points to keep in mind:
Any claims that you can lose weight effortlessly are false. The only proven way to lose weight is either to reduce the number of calories you eat or to increase the number of calories you burn off through exercise. Most experts recommend a combination of both.
Very low-calorie diets are not without risk and should be pursued only under medical supervision. Unsupervised very low-calorie diets can deprive you of important nutrients and are potentially dangerous.
Fad diets rarely have any permanent effect. Sudden and radical changes in your eating patterns are difficult to sustain over time. In addition, so-called 'crash' diets often send dieters into a cycle of quick weight loss, followed by a 'rebound' weight gain once normal eating resumes, and even more difficulty reducing when the next diet is attempted.
To lose weight safely and keep it off requires long-term changes in daily eating and exercise habits. Many experts recommend a goal of losing about a pound a week. A modest reduction of 500 calories per day will achieve this goal, since a total reduction of 3,500 calories is required to lose a pound of fat. An important way to lower your calorie intake is to learn and practice healthy eating habits.
In Search of the 'Magic Bullet'
Some dieters peg their hopes on pills and capsules that promise to 'burn,' 'block,' 'flush,' or otherwise eliminate fat from the system. But science has yet to come up with a low-risk 'magic bullet' for weight loss. Some pills may help control the appetite, but they can have serious side effects. (Amphetamines, for instance, are highly addictive and can have an adverse impact on the heart and central nervous system.) Other pills are utterly worthless.
The Federal Trade Commission and a number of state Attorney General have successfully brought cases against marketers of pills claiming to absorb or burn fat. The Food and Drug Administration has banned 111 ingredients once found in over-the-counter diet products. None of these substances, which include alcohol, caffeine, dextrose, and guar gum, have proved effective in weight-loss or appetite suppression.
Beware of the following products that are touted as weight-loss wonders:
Diet patches, which are worn on the skin, have not been proven to be safe or effective. The FDA has seized millions of these products from manufacturers and promoters.
'Fat blockers' purport to physically absorb fat and mechanically interfere with the fat a person eats.
'Starch blockers' promise to block or impede starch digestion. Not only is the claim unproven, but users have complained of nausea, vomiting, diarrhea, and stomach pains.
'Magnet' diet pills allegedly 'flush fat out of the body.' The FTC has brought legal action against several marketers of these pills.
Glucomannan is advertised as the 'Weight Loss Secret That's Been in the Orient for Over 500 Years.' There is little evidence supporting this plant root's effectiveness as a weight-loss product.
Some bulk producers or fillers, such as fiber-based products, may absorb liquid and swell in the stomach, thereby reducing hunger. Some fillers, such as guar gum, can even prove harmful, causing obstructions in the intestines, stomach, or esophagus. The FDA has taken legal action against several promoters containing guar gum.
Spirulina, a species of blue-green algae, has not been proven effective for losing weight.
Phony Devices and Gadgets
Phony weight-loss devices range from those that are simply ineffective to those that are truly dangerous to your health. At minimum, they are a waste of your hard-earned money. Some of the fraudulent gadgets that have been marketed to hopeful dieters over the years include:
Electrical muscle stimulators have legitimate use in physical therapy treatment. But the FDA has taken a number of them off the market because they were promoted for weight loss and body toning. When used incorrectly, muscle stimulators can be dangerous, causing electrical shocks and burns.
'Appetite suppressing eyeglasses' are common eyeglasses with colored lenses that claim to project an image to the retina which dampens the desire to eat. There is no evidence these work.
'Magic weight-loss earrings' and devices custom-fitted to the purchaser's ear that purport to stimulate acupuncture points controlling hunger have not been proven effective.
Diet Programs
Approximately 8 million Americans a year enroll in some kind of structured weight-loss program involving liquid diets, special diet regimens, or medical or other supervision. In 1991, about 8,500 commercial diet centers were in operation across the country, many of them owned by a half-dozen or so well-known national companies.
Before you join such a program, you should know that according to published studies relatively few participants succeed in keeping off weight long-term. Recently, the FTC brought action against several companies challenging weight-loss and weight-maintenance claims. Unfortunately, some other companies continue to make overblown claims.
The FTC stopped one company from claiming its diet program caused rapid weight loss through the use of tablets that would 'burn fat' and a protein drink mix that would adjust metabolism. The FTC also took action against three major programs using doctor-supervised, very low-calorie liquid diets, and they agreed to stop making claims unless they could back them up with hard data.
Before you sign up with a diet program, you might ask these questions:
What are the health risks?
What data can you show me that proves your program actually works?
Do customers keep off the weight after they leave the diet program? ?
What are the costs for membership, weekly fees, food, supplements, maintenance, and counseling? What's the payment schedule? Are any costs covered under health insurance? Do you give refunds if I drop out?
Do you have a maintenance program? Is it part of the package or does it cost extra?
What kind of professional supervision is provided? What are the credentials of these professionals?
What are the program's requirements? Are there special menus or foods, counseling visits, or exercise plans?
Clues to Fraud
It is important for consumers to be wary of claims that sound too good to be true. When it comes to weight-loss schemes, consumers should be particularly skeptical of claims containing words and phrases like:
easy
effortless
guaranteed
miraculous
magical
breakthrough
new discovery
mysterious
exotic
secret
exclusive
ancient
Sensible Weight Maintenance Tips
Losing weight may not be effortless, but it doesn't have to be complicated. To achieve long-term results, it's best to avoid quick-fix schemes and complex regimens. Focus instead on making modest changes to your life's daily routine. A balanced, healthy diet and sensible, regular exercise are the keys to maintaining your ideal weight. Although nutrition science is constantly evolving, here are some generally-accepted guidelines for losing weight:
Consult with your doctor, a dietician, or other qualified health professional to determine your ideal healthy body weight.
Eat smaller portions and choose from a variety of foods.
Load up on foods naturally high in fiber: Fruits, vegetables, legumes, and whole grains.
Limit portions of foods high in fat: dairy products like cheese, butter, and whole milk; red meat; cakes and pastries.
Exercise at least three times a week.
U. S. Food and Drug Administration
Ways to Win at Weight Loss
Americans trying to lose weight have plenty of company. According to a 1995 report from the Institute of Medicine, tens of millions of Americans are dieting at any given time, spending more than $33 billion yearly on weight-reduction products, such as diet foods and drinks.
Yet, studies over the last two decades by the National Center for Health Statistics show that obesity in the United States is actually on the rise. Today, approximately 35 percent of women and 31 percent of men age 20 and older are considered obese, up from approximately 30 percent and 25 percent, respectively, in 1980.
The words obesity and overweight are generally used interchangeably. However, according to the IOM report, their technical meanings are not identical. Overweight refers to an excess of body weight that includes all tissues, such as fat, bone and muscle. Obesity refers specifically to an excess of body fat. It is possible to be overweight without being obese, as in the case of a body builder who has a substantial amount of muscle mass. It is possible to be obese without being overweight, as in the case of a very sedentary person who is within the desirable weight range but who nevertheless has an excess of body fat. However, most overweight people are also obese and vice versa. Men with more than 25 percent and women with more than 30 percent body fat are considered obese.
Many people who diet fail to lose weight — or, if they do lose, fail to maintain the lower weight over the long term. As the IOM report, 'Weighing The Options: Criteria for Evaluating Weight-Management Programs,' points out, obesity is 'a complex, multifactorial disease of appetite regulation and energy metabolism.'
Because many factors affect how much or how little food a person eats and how that food is metabolized, or processed, by the body, losing weight is not simple. For example, recent studies suggest a role for genetic makeup in obesity. This area is still controversial, and more studies will be needed before scientists can say with certainty that a person's genes may set limits on how much weight can be lost and maintained.
Yet many people persist in seeking simple cures to this complex health problem. Lured by fad diets or pills that promise a quick and easy path to thinness, they end up disappointed when they regain lost weight.
No Shortcuts
'There are no shortcuts — no magic pills,' said Lori Love, M.D., Ph.D., of the Food and Drug Administration's Center for Food Safety and Applied Nutrition. Losing weight sensibly and safely requires a multifaceted approach that includes setting reasonable weight-loss goals, changing eating habits, and getting adequate exercise. Appetite suppressants (diet pills) or other products may help some people over the short term, but they are not a substitute for adopting healthful eating habits over the long term.
The first step in losing weight safely is to determine a realistic weight goal. The table, at right, developed by the U.S. Department of Agriculture and the Department of Health and Human Services, offers a range of suggested weights for adults based on their height.
A physician, dietitian or nutritionist also can help you set a reasonable goal. To reach the goal safely, plan to lose 1 to 2 pounds weekly by consuming approximately 300 to 500 fewer calories daily than usual (women and inactive men generally need to consume approximately 2,000 calories to maintain weight; men and very active women may consume up to 2,500 calories daily).
Moderation, Variety and Balance
After determining a reasonable goal weight, devise an eating plan based on the cornerstones of healthful eating — moderation, variety and balance, suggested Victor Herbert, M.D., J.D., professor of medicine and director of the Nutrition Center at the Mount Sinai School of Medicine and Bronx VA Medical Centers in New York City, and member of the board of directors of the National Council Against Health Fraud.
"Moderation means not eating too much or too little of any particular food or nutrient; variety means eating as wide a variety as possible from each, and within each, of the five basic food groups; and balance refers to the balance achieved by following moderation and variety, as well as the balance of calories consumed versus calories expended," he explained. To lose weight, fewer calories should be consumed than expended; to maintain weight loss, the number of calories consumed and expended should be about the same.
Because fat is the most concentrated source of calories (9 calories per gram compared to 4 calories per gram for carbohydrate and protein), it is usually the focus of weight-maintenance and weight-loss diets. Limiting fat intake alone will likely limit calories, as well. Just as for the general population, weight-conscious consumers should limit fat intake to no more than 30 percent of total calories, according to the Dietary Guidelines for Americans.
Alcoholic beverages also are a source of calories (7 per gram of alcohol). Twelve ounces of regular beer, for example, provides 150 calories; the same amount of 'light' beer, 105 calories. Five ounces of wine or 1.5 ounces of 80-proof distilled spirits provide 100 calories. But alcohol provides few, if any, nutrients, so if you drink alcoholic beverages and want to reduce your weight, consider reducing or eliminating your alcohol intake.
In selecting your diet, follow the five basic food groups and the recommended number of servings from each as incorporated into the Food Guide Pyramid developed by USDA and HHS. These groups are (1) bread, cereal, pasta, and rice; (2) vegetables; (3) fruits; (4) milk, yogurt and cheese; and (5) meat, poultry, fish, dry beans, eggs, and nuts. A sixth group (fats, oils and sweets) consists mainly of items that are pleasing to the palate but high in fat and/or calories; these should be eaten in moderation.
Avoid low-calorie fad diets that exclude whole categories of food such as carbohydrates (bread and pasta) or proteins (meat and poultry). These diets may be harmful because they generally do not include all nutrients necessary for good health. "Every fad diet that demands an unusual eating pattern, such as emphasizing only a few types of foods, deviates from one or more of the guidelines of moderation, variety and balance," Herbert said. 'The greater the deviation, the more harmful the diet is likely to be."
Using the Food Label
To help consumers plan a healthful diet, FDA and USDA have revamped food labels. By law, most food labels now must display a Nutrition Facts panel containing information about how the food can fit into an overall daily diet. Nutrition Facts state how much saturated fat, cholesterol, fiber, and certain nutrients are contained in each serving.
On the food label, %Daily Value shows what percentage of a given nutrient is provided in one portion for daily diets of 2,000 calories.
Whether or not a given food fits into a weight-loss diet depends on what other foods you eat that day. For most people, the goal is to select a variety of foods that together add up to approximately 100 percent of the Daily Value for total carbohydrate, dietary fiber, vitamins, and minerals; total fat, cholesterol and sodium each may add up to less than 100 percent.
Foods that claim to contain fewer calories or less fat than similar servings of similar products must show the difference on the label. For example, on a container of low-fat cottage cheese, the label would show that a serving of the low-fat product contains 80 calories and 1.5 grams of fat while regular cottage cheese contains 120 calories and 5 grams of fat per serving.
Camille Brewer, a registered dietitian and nutritionist in FDA's Center for Food Safety and Applied Nutrition, advised caution, however, when choosing foods that are labeled 'fat-free' and 'low-fat.' Some of these foods, like 'low-fat' cakes and cookies, still may be high in calories because of added sugars. So dieters should always check the Nutrition Facts panel to get complete information, she said.
Look for foods high in fiber, such as fruits, vegetables, legumes and whole grains. Fiber can be an important aid in weight maintenance because eating enough of it can help make a person feel full and thus not eat as much.
To see how the new label can help you stick to your diet, see Dieters' Label Checklist (a 119K PDF file)
Exercise
Regular exercise is important for overall health, as well as for losing and maintaining weight. There is evidence to suggest that body fat distribution affects health risks. For example, excess fat in the abdominal area (as opposed to hips and thighs) is associated with greater risk for high blood pressure, diabetes, early heart disease, and certain types of cancer. Vigorous exercise can reduce abdominal fat and thus lower the risk of these diseases.
The Dietary Guidelines for Americans recommends a half hour or more of moderate physical activity on most days, preferably every day. The activity can include brisk walking, calisthenics, home care, gardening, moderate sports exercise, and dancing. Regular exercise can help the body use up calories consumed daily, as well as excess calories stored as fat. Weight-bearing exercises also help tone muscles and may reduce the risk of osteoporosis.
OTC Diet Pills
The 1991/1992 Weight Loss Practices Survey, sponsored by FDA and the National Heart, Lung, and Blood Institute, found that 5 percent of women and 2 percent of men trying to lose weight use diet pills. Products considered by FDA to be over-the-counter weight control drugs are primarily those containing the active ingredient phenylpropanolamine, such as Dexatrim and Acutrim. PPA is available OTC for weight control in a 75-mg controlled-release dosage form. The medicine should be used in combination with a restricted diet and exercise.
Using diet pills containing PPA will not make a big difference in the rate of weight loss, said Robert Sherman of FDA's Office of OTC Drug Evaluation. 'Even the best studies show only about a half pound greater weight loss per week using PPA combined with diet and exercise,' he added. Sherman cautions that the recommended dosage of these pills should not be exceeded because of the risk of possible adverse effects, such as elevated blood pressure and heart palpitations.
Since PPA is also used as a nasal decongestant in over-the-counter cough and cold products, consumers should read the labels of OTC decongestants to see if they contain PPA. They should not take PPA in two products labeled for different uses.
Sherman notes that FDA has received a small number of reports indicating that PPA use might be associated with an increased risk of stroke. A large-scale safety study was begun in September 1994 to explore the possibility. Based on available data, the agency does not believe that an increased risk of stroke is a concern when PPA is used at recommended dosages.
Rx Drugs
FDA has approved several prescription drugs for obesity. The newest is Xenical (orlistat), which FDA approved in April 1999.
Xenical is the first in a new class of anti-obesity drugs known as lipase inhibitors. Lipase is the enzyme that breaks down fat for use by the body. Xenical interferes with lipase function, decreasing fat absorption by 30 percent. Since undigested fats are not absorbed, there is less calorie intake, which may have a positive effect on weight control.
Other approved anti-obesity prescription drugs available on the market include:
Dexedrine and other amphetamines
Ionamin and Adipex-P (phentermine), Sanorex (mazindol), Tenuate (diethylpropion), Prelu-2 (phendimetrazine) and other amphetamine derivatives
Meridia (sibutramine).
In mostly short-term studies of obese adults following a calorie-restricted diet, those who took the appetite suppressants lost more weight on average than those who took a placebo. The amount of weight lost varied from study to study.
FDA approved the drugs only for use with calorie-restricted diets. The drugs are 'not magic pills,' warned Leo Lutwak, M.D., Ph.D., of FDA's division of metabolism and endocrine drug products. "They don't work unless you make dietary and exercise changes."
Also, they should be used only for a few weeks partly because, aside from Xenical, the drugs are addictive and have the potential for abuse. They shouldn't be used in combination with each other or with other drugs for appetite control because such combinations have not been evaluated for safety. And the drugs should be used only in people who are obese — not people looking to lose a few pounds, Lutwak said.
"Weight-loss drugs are serious medicine for a serious disease," he said.
Also, he pointed out that while obesity may be associated with other serious diseases, studies have never shown that weight loss produced with the use of prescription weight-loss drugs benefits obesity-associated conditions. However, changes in diet and activity may improve associated diseases, such as diabetes and high blood pressure, even with only modest changes in weight, Lutwak said.
Until September 1997, two other drugs, fenfluramine (Pondimin and others) and dexfenfluramine (Redux), were available for treating obesity. But, at FDA's request, the manufacturers of these drugs voluntarily withdrew them from the market after newer findings suggested that they were the likely cause of heart valve problems in a large proportion of people using them. FDA recommended that anyone taking the drugs stop and that they contact their doctor to discuss their treatment. (For the latest information on this topic, visit www.fda.gov/cder/news/feninfo.htm on FDA's Website.)
Weight-Loss Programs
Many people turn to weight-loss programs for help in planning a daily diet and changing lifestyle habits. The IOM report provides guidelines for evaluating the potential effectiveness of such programs.
"To improve their chances for success, consumers should choose programs that focus on long-term weight management; provide instruction in healthful eating, increasing activity, and improving self-esteem; and explain thoroughly the potential health risks from weight loss," according to the report. Consumers should also demand evidence of success. If it is absent or consists primarily of testimonials or other anecdotal evidence, "the program should be viewed with suspicion."
IOM recommends that potential clients be given a truthful, unambiguous, non-misleading statement about the program's approaches and goals, and a full disclosure of costs. The cost breakdown should include initial and ongoing costs, as well as the cost of extra products.
The basic tenet of weight loss — to eat fewer calories than you burn and to stay active — is easy to say but, like most lifestyle changes, not so easy to do. With realistic goals, and a commitment to losing weight slowly, safely and sensibly, the chances of long-term success improve dramatically.
Marilynn Larkin is a writer in New York City. Paula Kurtzweil, a member of FDA's public affairs staff, also contributed to this article.
Obesity a Disease
Obesity is now considered a disease--not a moral failing. According to a 1995 report from the Institute of Medicine, 'obesity is a heterogeneous disease in which genetic, environmental, psychological, and other factors are involved. It occurs when energy intake exceeds the amount of energy expended over time. Only in a small minority of cases is obesity caused by such illnesses as hypothyroidism or the result of taking medications, such as steroids, that can cause weight gain.'
Public health concerns about this disease relate to its link to numerous other diseases that can lead to premature illness or death. The report notes that overweight individuals who lose even relatively small amounts of weight are likely to:
lower their blood pressure (and thereby the risk of heart attack and stroke)
reduce abnormally high levels of blood glucose (associated with diabetes)
bring blood levels of cholesterol and triglycerides (associated with cardiovascular disease) down to more desirable levels
reduce sleep apnea, or irregular breathing during sleep
decrease the risk of osteoarthritis of the weight-bearing joints
decrease depression
increase self-esteem.
Of course, losing excess weight is also likely to improve appearance, which is a strong motivation for many people.
by Marilynn Larkins
This article combines two articles that originally appeared in the July-August 1994 and January-February 1996 issues of FDA Consumer and contains revisions made in May 1998 and May 1999.
Publication No. (FDA) 99-1287
Yet, studies over the last two decades by the National Center for Health Statistics show that obesity in the United States is actually on the rise. Today, approximately 35 percent of women and 31 percent of men age 20 and older are considered obese, up from approximately 30 percent and 25 percent, respectively, in 1980.
The words obesity and overweight are generally used interchangeably. However, according to the IOM report, their technical meanings are not identical. Overweight refers to an excess of body weight that includes all tissues, such as fat, bone and muscle. Obesity refers specifically to an excess of body fat. It is possible to be overweight without being obese, as in the case of a body builder who has a substantial amount of muscle mass. It is possible to be obese without being overweight, as in the case of a very sedentary person who is within the desirable weight range but who nevertheless has an excess of body fat. However, most overweight people are also obese and vice versa. Men with more than 25 percent and women with more than 30 percent body fat are considered obese.
Many people who diet fail to lose weight — or, if they do lose, fail to maintain the lower weight over the long term. As the IOM report, 'Weighing The Options: Criteria for Evaluating Weight-Management Programs,' points out, obesity is 'a complex, multifactorial disease of appetite regulation and energy metabolism.'
Because many factors affect how much or how little food a person eats and how that food is metabolized, or processed, by the body, losing weight is not simple. For example, recent studies suggest a role for genetic makeup in obesity. This area is still controversial, and more studies will be needed before scientists can say with certainty that a person's genes may set limits on how much weight can be lost and maintained.
Yet many people persist in seeking simple cures to this complex health problem. Lured by fad diets or pills that promise a quick and easy path to thinness, they end up disappointed when they regain lost weight.
No Shortcuts
'There are no shortcuts — no magic pills,' said Lori Love, M.D., Ph.D., of the Food and Drug Administration's Center for Food Safety and Applied Nutrition. Losing weight sensibly and safely requires a multifaceted approach that includes setting reasonable weight-loss goals, changing eating habits, and getting adequate exercise. Appetite suppressants (diet pills) or other products may help some people over the short term, but they are not a substitute for adopting healthful eating habits over the long term.
The first step in losing weight safely is to determine a realistic weight goal. The table, at right, developed by the U.S. Department of Agriculture and the Department of Health and Human Services, offers a range of suggested weights for adults based on their height.
A physician, dietitian or nutritionist also can help you set a reasonable goal. To reach the goal safely, plan to lose 1 to 2 pounds weekly by consuming approximately 300 to 500 fewer calories daily than usual (women and inactive men generally need to consume approximately 2,000 calories to maintain weight; men and very active women may consume up to 2,500 calories daily).
Moderation, Variety and Balance
After determining a reasonable goal weight, devise an eating plan based on the cornerstones of healthful eating — moderation, variety and balance, suggested Victor Herbert, M.D., J.D., professor of medicine and director of the Nutrition Center at the Mount Sinai School of Medicine and Bronx VA Medical Centers in New York City, and member of the board of directors of the National Council Against Health Fraud.
"Moderation means not eating too much or too little of any particular food or nutrient; variety means eating as wide a variety as possible from each, and within each, of the five basic food groups; and balance refers to the balance achieved by following moderation and variety, as well as the balance of calories consumed versus calories expended," he explained. To lose weight, fewer calories should be consumed than expended; to maintain weight loss, the number of calories consumed and expended should be about the same.
Because fat is the most concentrated source of calories (9 calories per gram compared to 4 calories per gram for carbohydrate and protein), it is usually the focus of weight-maintenance and weight-loss diets. Limiting fat intake alone will likely limit calories, as well. Just as for the general population, weight-conscious consumers should limit fat intake to no more than 30 percent of total calories, according to the Dietary Guidelines for Americans.
Alcoholic beverages also are a source of calories (7 per gram of alcohol). Twelve ounces of regular beer, for example, provides 150 calories; the same amount of 'light' beer, 105 calories. Five ounces of wine or 1.5 ounces of 80-proof distilled spirits provide 100 calories. But alcohol provides few, if any, nutrients, so if you drink alcoholic beverages and want to reduce your weight, consider reducing or eliminating your alcohol intake.
In selecting your diet, follow the five basic food groups and the recommended number of servings from each as incorporated into the Food Guide Pyramid developed by USDA and HHS. These groups are (1) bread, cereal, pasta, and rice; (2) vegetables; (3) fruits; (4) milk, yogurt and cheese; and (5) meat, poultry, fish, dry beans, eggs, and nuts. A sixth group (fats, oils and sweets) consists mainly of items that are pleasing to the palate but high in fat and/or calories; these should be eaten in moderation.
Avoid low-calorie fad diets that exclude whole categories of food such as carbohydrates (bread and pasta) or proteins (meat and poultry). These diets may be harmful because they generally do not include all nutrients necessary for good health. "Every fad diet that demands an unusual eating pattern, such as emphasizing only a few types of foods, deviates from one or more of the guidelines of moderation, variety and balance," Herbert said. 'The greater the deviation, the more harmful the diet is likely to be."
Using the Food Label
To help consumers plan a healthful diet, FDA and USDA have revamped food labels. By law, most food labels now must display a Nutrition Facts panel containing information about how the food can fit into an overall daily diet. Nutrition Facts state how much saturated fat, cholesterol, fiber, and certain nutrients are contained in each serving.
On the food label, %Daily Value shows what percentage of a given nutrient is provided in one portion for daily diets of 2,000 calories.
Whether or not a given food fits into a weight-loss diet depends on what other foods you eat that day. For most people, the goal is to select a variety of foods that together add up to approximately 100 percent of the Daily Value for total carbohydrate, dietary fiber, vitamins, and minerals; total fat, cholesterol and sodium each may add up to less than 100 percent.
Foods that claim to contain fewer calories or less fat than similar servings of similar products must show the difference on the label. For example, on a container of low-fat cottage cheese, the label would show that a serving of the low-fat product contains 80 calories and 1.5 grams of fat while regular cottage cheese contains 120 calories and 5 grams of fat per serving.
Camille Brewer, a registered dietitian and nutritionist in FDA's Center for Food Safety and Applied Nutrition, advised caution, however, when choosing foods that are labeled 'fat-free' and 'low-fat.' Some of these foods, like 'low-fat' cakes and cookies, still may be high in calories because of added sugars. So dieters should always check the Nutrition Facts panel to get complete information, she said.
Look for foods high in fiber, such as fruits, vegetables, legumes and whole grains. Fiber can be an important aid in weight maintenance because eating enough of it can help make a person feel full and thus not eat as much.
To see how the new label can help you stick to your diet, see Dieters' Label Checklist (a 119K PDF file)
Exercise
Regular exercise is important for overall health, as well as for losing and maintaining weight. There is evidence to suggest that body fat distribution affects health risks. For example, excess fat in the abdominal area (as opposed to hips and thighs) is associated with greater risk for high blood pressure, diabetes, early heart disease, and certain types of cancer. Vigorous exercise can reduce abdominal fat and thus lower the risk of these diseases.
The Dietary Guidelines for Americans recommends a half hour or more of moderate physical activity on most days, preferably every day. The activity can include brisk walking, calisthenics, home care, gardening, moderate sports exercise, and dancing. Regular exercise can help the body use up calories consumed daily, as well as excess calories stored as fat. Weight-bearing exercises also help tone muscles and may reduce the risk of osteoporosis.
OTC Diet Pills
The 1991/1992 Weight Loss Practices Survey, sponsored by FDA and the National Heart, Lung, and Blood Institute, found that 5 percent of women and 2 percent of men trying to lose weight use diet pills. Products considered by FDA to be over-the-counter weight control drugs are primarily those containing the active ingredient phenylpropanolamine, such as Dexatrim and Acutrim. PPA is available OTC for weight control in a 75-mg controlled-release dosage form. The medicine should be used in combination with a restricted diet and exercise.
Using diet pills containing PPA will not make a big difference in the rate of weight loss, said Robert Sherman of FDA's Office of OTC Drug Evaluation. 'Even the best studies show only about a half pound greater weight loss per week using PPA combined with diet and exercise,' he added. Sherman cautions that the recommended dosage of these pills should not be exceeded because of the risk of possible adverse effects, such as elevated blood pressure and heart palpitations.
Since PPA is also used as a nasal decongestant in over-the-counter cough and cold products, consumers should read the labels of OTC decongestants to see if they contain PPA. They should not take PPA in two products labeled for different uses.
Sherman notes that FDA has received a small number of reports indicating that PPA use might be associated with an increased risk of stroke. A large-scale safety study was begun in September 1994 to explore the possibility. Based on available data, the agency does not believe that an increased risk of stroke is a concern when PPA is used at recommended dosages.
Rx Drugs
FDA has approved several prescription drugs for obesity. The newest is Xenical (orlistat), which FDA approved in April 1999.
Xenical is the first in a new class of anti-obesity drugs known as lipase inhibitors. Lipase is the enzyme that breaks down fat for use by the body. Xenical interferes with lipase function, decreasing fat absorption by 30 percent. Since undigested fats are not absorbed, there is less calorie intake, which may have a positive effect on weight control.
Other approved anti-obesity prescription drugs available on the market include:
Dexedrine and other amphetamines
Ionamin and Adipex-P (phentermine), Sanorex (mazindol), Tenuate (diethylpropion), Prelu-2 (phendimetrazine) and other amphetamine derivatives
Meridia (sibutramine).
In mostly short-term studies of obese adults following a calorie-restricted diet, those who took the appetite suppressants lost more weight on average than those who took a placebo. The amount of weight lost varied from study to study.
FDA approved the drugs only for use with calorie-restricted diets. The drugs are 'not magic pills,' warned Leo Lutwak, M.D., Ph.D., of FDA's division of metabolism and endocrine drug products. "They don't work unless you make dietary and exercise changes."
Also, they should be used only for a few weeks partly because, aside from Xenical, the drugs are addictive and have the potential for abuse. They shouldn't be used in combination with each other or with other drugs for appetite control because such combinations have not been evaluated for safety. And the drugs should be used only in people who are obese — not people looking to lose a few pounds, Lutwak said.
"Weight-loss drugs are serious medicine for a serious disease," he said.
Also, he pointed out that while obesity may be associated with other serious diseases, studies have never shown that weight loss produced with the use of prescription weight-loss drugs benefits obesity-associated conditions. However, changes in diet and activity may improve associated diseases, such as diabetes and high blood pressure, even with only modest changes in weight, Lutwak said.
Until September 1997, two other drugs, fenfluramine (Pondimin and others) and dexfenfluramine (Redux), were available for treating obesity. But, at FDA's request, the manufacturers of these drugs voluntarily withdrew them from the market after newer findings suggested that they were the likely cause of heart valve problems in a large proportion of people using them. FDA recommended that anyone taking the drugs stop and that they contact their doctor to discuss their treatment. (For the latest information on this topic, visit www.fda.gov/cder/news/feninfo.htm on FDA's Website.)
Weight-Loss Programs
Many people turn to weight-loss programs for help in planning a daily diet and changing lifestyle habits. The IOM report provides guidelines for evaluating the potential effectiveness of such programs.
"To improve their chances for success, consumers should choose programs that focus on long-term weight management; provide instruction in healthful eating, increasing activity, and improving self-esteem; and explain thoroughly the potential health risks from weight loss," according to the report. Consumers should also demand evidence of success. If it is absent or consists primarily of testimonials or other anecdotal evidence, "the program should be viewed with suspicion."
IOM recommends that potential clients be given a truthful, unambiguous, non-misleading statement about the program's approaches and goals, and a full disclosure of costs. The cost breakdown should include initial and ongoing costs, as well as the cost of extra products.
The basic tenet of weight loss — to eat fewer calories than you burn and to stay active — is easy to say but, like most lifestyle changes, not so easy to do. With realistic goals, and a commitment to losing weight slowly, safely and sensibly, the chances of long-term success improve dramatically.
Marilynn Larkin is a writer in New York City. Paula Kurtzweil, a member of FDA's public affairs staff, also contributed to this article.
Obesity a Disease
Obesity is now considered a disease--not a moral failing. According to a 1995 report from the Institute of Medicine, 'obesity is a heterogeneous disease in which genetic, environmental, psychological, and other factors are involved. It occurs when energy intake exceeds the amount of energy expended over time. Only in a small minority of cases is obesity caused by such illnesses as hypothyroidism or the result of taking medications, such as steroids, that can cause weight gain.'
Public health concerns about this disease relate to its link to numerous other diseases that can lead to premature illness or death. The report notes that overweight individuals who lose even relatively small amounts of weight are likely to:
lower their blood pressure (and thereby the risk of heart attack and stroke)
reduce abnormally high levels of blood glucose (associated with diabetes)
bring blood levels of cholesterol and triglycerides (associated with cardiovascular disease) down to more desirable levels
reduce sleep apnea, or irregular breathing during sleep
decrease the risk of osteoarthritis of the weight-bearing joints
decrease depression
increase self-esteem.
Of course, losing excess weight is also likely to improve appearance, which is a strong motivation for many people.
by Marilynn Larkins
This article combines two articles that originally appeared in the July-August 1994 and January-February 1996 issues of FDA Consumer and contains revisions made in May 1998 and May 1999.
Publication No. (FDA) 99-1287
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