January-February 2002; revised April 2002, March 2003, and April 2004
By Linda Bren
Americans are getting fatter. We're putting on the pounds at an alarmingly rapid rate. And we're sacrificing our health for the sake of super-sized portions, biggie drinks, and two-for-one value meals, obesity researchers say.
More than 60 percent of U.S. adults are overweight, according to the Centers for Disease Control and Prevention (CDC). And about 15 percent of children and adolescents ages 6 to 19 are overweight.
Poor diet and physical inactivity account for more than 400,000 premature deaths each year in the United States, second only to deaths related to smoking, says the CDC. People who are overweight or obese are more likely to develop heart disease, stroke, high blood pressure, diabetes, gallbladder disease, and joint pain caused by excess uric acid (gout). Excess weight can also cause interrupted breathing during sleep (sleep apnea) and wearing away of the joints (osteoarthritis). Carrying extra weight means carrying an extra risk for certain types of cancer, including endometrial, breast, prostate, and colon cancer.
But there is hope for overweight Americans. They can take small, achievable steps to improve their health and reverse the obesity epidemic. This message is the cornerstone of a national education campaign announced in March 2004 by the Department of Health and Human Services (HHS).
As part of HHS' renewed efforts to combat obesity, the Food and Drug Administration's Obesity Working Group released its Calories Count report in March 2004, highlighting actions that the agency will work toward to help consumers make smart choices about their diet. These actions include strengthening food labeling, educating consumers about maintaining a healthy diet and weight, and encouraging restaurants to provide calorie and nutrition information. Also included are increased enforcement to ensure food labels accurately portray serving size and strengthened scientific research aimed at reducing obesity and developing foods that are healthier and lower in calories.
Overweight refers to an excess of body weight, but not necessarily body fat. Obesity means an excessively high proportion of body fat. Health professionals use a measurement called body mass index (BMI) to classify an adult's weight as healthy, overweight, or obese. BMI describes body weight relative to height and is correlated with total body fat content in most adults.
To get your approximate BMI, multiply your weight in pounds by 703, then divide the result by your height in inches, and divide that result by your height in inches a second time. (Or you can use the interactive BMI calculator at www.nhlbisupport.com/bmi/bmicalc.htm.)
A BMI from 18.5 up to 25 is considered in the healthy range, from 25 up to 30 is overweight, and 30 or higher is obese. Generally, the higher a person's BMI, the greater the risk for health problems, according to the National Heart, Lung and Blood Institute (NHLBI). However, there are some exceptions. For example, very muscular people, like body builders, may have a BMI greater than 25 or even 30, but this reflects increased muscle rather than fat. "It is excess body fat that leads to the health problems such as type 2 diabetes, high blood pressure, and high cholesterol," says Eric Colman, M.D., of the FDA's Division of Metabolic and Endocrine Drug Products.
In addition to a high BMI, having excess abdominal body fat is a health risk. Men with a waist of more than 40 inches around and women with a waist of 35 inches or more are at risk for health problems.
Obesity, once thought by many to be a moral failing, is now often classified as a disease. The NHLBI calls it a complex chronic disease involving social, behavioral, cultural, physiological, metabolic, and genetic factors. Although experts may have different theories on how and why people become overweight, they generally agree that the key to losing weight is a simple message: Eat less and move more. Your body needs to burn more calories than you take in.
The BMI ranges shown at left are for adults. They are not exact ranges of healthy and unhealthy weights. However, they show that health risk increases at higher levels of overweight and obesity. Even within the healthy BMI range, weight gains can carry health risks for adults.
Directions: Find your weight on the bottom of the graph. Go straight up from that point until you come to the line that matches your height. Then look to find your weight group.
Healthy Weight: BMI from 18.5 up to 25 refers to healthy weight.
Overweight: BMI from 25 up to 30 refers to overweight.
Obese: BMI 30 or higher refers to obesity. Obese persons are
Although many people who lose weight may eventually gain it back, it's a myth that this happens to everyone, says Rena Wing, Ph.D., a professor of psychiatry at Brown Medical School in Providence, R.I. Wing, the co-developer of a research study known as the National Weight Control Registry, has worked to deflate this myth.
Tucked away in the registry's database is information about the weight-control behaviors of more than 3,000 American adults who have lost an average of 60 pounds and have kept it off for an average of six years.
How do they do it?
These successful weight losers report four common behaviors, says Wing. They eat a low-calorie, low-fat diet, they monitor themselves by weighing in frequently, they are very physically active, and they eat breakfast. Eating breakfast every day is contrary to the typical pattern for the average overweight person who is trying to diet, says Wing. "They get up in the morning and say 'I'm going to start my diet today,' and they eat little or no breakfast and a light lunch. Then they get hungry and consume most of their calories late in the day. Successful weight losers have managed to change this pattern."
Six years after their weight loss, most of the registry's successful losers still report eating a low-calorie, low-fat diet. They also exercise for about an hour or more a day, expending about 2,800 calories per week on a variety of activities.
Wing also reports that more than 70 percent of the registry's weight losers became overweight before age 18.
Although Barbara Croft of Columbus, Ohio, was not an overweight child, she gained weight once she left home and started cooking for herself. Replacing the plain and simple meals she had as a child with pizza, sodas, and meat and vegetables laden with sauces, the 5-foot-5-inch Croft worked her way up to 350 pounds. "I always ate from all the food groups--I just ate huge portions and I ate in between meals," says Croft.
When she was diagnosed with type 2 diabetes in February 1999, Croft got scared. "I worried about the health consequences--about going blind. I already have a little numbness in my feet."
Croft went on a diet and lost 200 pounds in 19 months. She has continued to keep it off for more than three years. "This is the third time I've lost over 100 pounds," says the 52-year-old, 150-pound Croft, "but this is the longest I've been able to keep the weight off." In her two previous weight losses, Croft ate nutritious meals, but didn't exercise. This time, she started walking for exercise, but could only walk about a block at first. "My husband went with me because he was afraid I wouldn't make it," she says. Now, Croft walks on a treadmill for 50 minutes a day--25 minutes each morning and night.
She still eats balanced meals, but restricts her portions. And she always eats breakfast. "I have Egg Beaters, two pieces of low-calorie bread, fruit, decaf coffee, and 8 ounces of water." Croft dines out almost every night, typically eating half her dinner of grilled chicken or salmon and a vegetable or salad. She sends the other half back so she isn't tempted to overeat.
"Losing the weight was easy--maintaining it is much harder," says Croft.
Croft had tried commercial weight-loss programs in the past, but this last time she did it on her own. "You have to find out what works for you," she says.
Croft's diabetes is under control now without medication. And she says her knees don't hurt anymore, she can buy clothes in a regular store, and she started traveling again now that she can fit into an airplane seat.
The first step to weight loss is setting a realistic goal. By using a BMI chart and consulting with your health care provider, you can determine what is a healthy weight for you.
Studies show that you can improve your health with just a small amount of weight loss. "We know that physical activity in combination with reduced calorie consumption can lead to the 5 to 10 percent weight loss necessary to achieve remission of the obesity-associated complications," says William Dietz, M.D., Ph.D., director of the Division of Nutrition and Physical Activity at the CDC. "Even these moderate weight losses can improve blood pressure and help control diabetes and high cholesterol in obese or overweight adults."
To reach your goal safely, plan to lose weight gradually. A weight loss of one-half to two pounds a week is usually safe, according to the Dietary Guidelines for Americans 2000. This can be achieved by decreasing the calories eaten or increasing the calories used by 250 to 1,000 calories per day, depending on current calorie intake. (Some people with serious health problems due to obesity may lose weight more rapidly under a doctor's supervision.) If you plan to lose more than 15 to 20 pounds, have any health problems, or take medication on a regular basis, see your health care professional before you begin a weight-loss program.
Dieting may conjure up visions of eating little but lettuce and sprouts--but you can enjoy all foods as part of a healthy diet as long as you don't overdo it. To be successful at losing weight, you need to change your lifestyle--not just go on a diet, experts say. This requires cutting back on the number of calories you eat by eating smaller amounts of foods and choosing foods lower in calories. It also means being more physically active.
Consider limiting portion sizes, especially of foods high in calories, such as cookies, cakes and other sweets; fried foods, like fried chicken and french fries; and fats, oils, and spreads. Reducing dietary fat alone--without reducing calories--will not produce weight loss, according to the NHLBI's guidelines on treating overweight and obesity in adults.
Use the Food Guide Pyramid developed by the U.S. Department of Agriculture and HHS to help you choose a healthful assortment of foods. Include bright-colored (red, yellow, green, and orange) vegetables and fruits, grains (especially whole grains), low-fat or fat-free milk, and fish, lean meat, poultry, or beans. Choose foods naturally high in fiber, such as fruits, vegetables, legumes (such as beans and lentils), and whole grains. The high fiber content of many of these foods may help you to feel full with fewer calories. To be sure that a food is whole grain, check the ingredient list on the food label--the first ingredient should be whole wheat or whole grain.
All calorie sources are not created equal. Carbohydrate and protein have about four calories per gram, but all fats, including oils like olive and canola oil, have more than twice that amount (nine calories per gram).
Keep your intake of saturated fat, trans fat, and cholesterol as low as possible. All of these fats raise LDL (or "bad
cholesterol"), which increases your risk for coronary heart disease. Foods high in saturated fats include high-fat dairy products (like cheese, whole milk, cream, butter, and regular ice cream), fatty fresh and processed meats, the skin and fat of poultry, lard, palm oil, and coconut oil. Trans fat can often be found in processed foods made with partially hydrogenated vegetable oils such as vegetable shortenings, some margarines (for example, stick margarines that are hard), crackers, cookies, candies, snack foods, fried foods and baked goods.
If you drink alcoholic beverages, do so in moderation (no more than one drink a day for women, and no more than two drinks a day for men). Alcoholic beverages supply calories but few nutrients. A 12-ounce regular beer contains about 150 calories, a 5-ounce glass of wine about 100 calories, and 1.5 ounces of 80-proof distilled spirits about 100 calories.
Limit your use of beverages and foods that are high in added sugars--those added to foods in processing or preparation, not the naturally occurring sugars in foods such as fruit or milk. Foods high in added sugars provide calories, but may have few of the other beneficial nutrients, such as fiber, vitamins, and minerals, that your body needs. A food high in added sugars will list a sugar as the first or second ingredient on the ingredient list. Some examples of added sugars are corn syrup, high fructose corn syrup, maltose, dextrose, honey, fruit juice concentrates, and maple syrup. In the United States, foods high in added sugars include non-diet soft drinks, sweetened beverages, including teas, fruit drinks, and fruitades, sweets and candies, and cakes and cookies.
Under regulations from the FDA and the U. S. Department of Agriculture, the food label, found on almost all processed foods, offers more complete, useful and accurate nutrition information than ever before. Even when restricting calories and portions, you should use the Nutrition Facts panel on the food label to make sure you get all the essential nutrients for good health.
When concerned about reducing calories or controlling your weight, one of the first places you should look on the Nutrition Facts panel is the serving size and the number of servings per package, which are listed at the top. The serving size affects the calories, the amounts of each nutrient, and the percent Daily Values (%DV) for the nutrients listed on the panel.
"To be sure you know how many calories you're consuming, you need to compare what you are actually eating to the serving size on the label," says Naomi Kulakow, coordinator for education and outreach in the FDA's Center for Food Safety and Applied Nutrition. For example, if there is one cup in a serving and the package contains two servings, you need to double the calories and other nutrient numbers if you eat the whole package. Many items sold as single portions--like a 20-ounce soft drink, a 3-ounce bag of chips, and a large bagel--actually provide two or more servings.
In addition to calories and serving sizes, there are other parts of the Nutrition Facts panel, such as the list of nutrients, that can help you make healthy food choices while you lose weight. The nutrients listed first are the ones that some people eat more of than they need. Eating too much fat, saturated fat, trans fat, cholesterol, or sodium may increase your risk for chronic diseases like heart disease, diabetes, some cancers, or high blood pressure. "These are nutrients you should try to limit in your diet," says Kulakow. "The goal is to stay below 100 percent of the Daily Value for each of them for the day."
The Nutrition Facts panel also shows how much dietary fiber, vitamin A, vitamin C, calcium, and iron are contained in a serving. These are the nutrients you want to get at least 100 percent of the Daily Value every day for good health.
The %DV is the quickest way to determine how a serving of food fits in with recommendations for a healthful diet, says Kulakow. To tell if a food is high or low in a nutrient, "just glance at the %DV--5 percent of the Daily Value or less is low, and 20 percent or more is high," she says.
You can also use the %DV to compare similar products or to help you balance food choices throughout the day. "For example, if you eat a favorite food that's high in fat at one meal, balance it with low-fat foods at other times of the day," says Kulakow. Or use the %DV when comparing foods and claims, for example, to find out which frozen dinner is lower in saturated fat--particularly when it involves a comparative nutrient claim, such as reduced-fat. "You don't need to know the precise definition of 'low' or 'reduced,'" says Kulakow. "Just look at the Percent Daily Value and see which product is higher or lower in the nutrient you are interested in."
The %DVs are based on a 2,000-calorie daily diet. But even if you eat more or less than 2,000 calories, the %DV still gives you a frame of reference to gauge your calorie and nutrient intake.
"Too often, people use the food label only when they want to restrict calories and fat--but not as a tool to help them increase the nutrients they need to get in adequate or greater amounts," says Kulakow. While restricting calories is important for weight loss, getting adequate amounts of fiber, calcium, and other key nutrients is also critical to good health.
Kulakow advises caution when choosing foods that are labeled "fat-free" and "low-fat." Fat-free doesn't mean calorie-free. To make a food tastier, sometimes extra sugars are added, which adds calories. (See "Fat-Free vs. Regular Calorie Comparison.") So dieters should always check the Nutrition Facts panel to get complete information, says Kulakow.
Get further guidance on using the Nutrition Facts panel on this Web site.
Most health experts recommend a combination of a reduced-calorie diet and increased physical activity for weight loss.
In addition to helping to control weight, physical activity decreases the risk of dying from coronary heart disease and reduces the risk of developing diabetes, hypertension, and certain cancers. Researchers also have found that daily physical activity may help a person lose weight by partially lessening the slow-down in metabolism that occurs during weight loss.
Exercise does not have to be strenuous to be beneficial. And some studies show that short sessions of exercise several times a day are just as effective at burning calories and improving health as one long session.
To lose weight and to maintain a healthy weight after weight loss, many adults will likely need to do more than 30 minutes of moderate to intensive physical activity daily.
For obese people who have difficulty losing weight through diet and exercise alone, there are a number of FDA-approved prescription drugs that may help. "On average, individuals who use weight-loss drugs lose about 5 percent to 10 percent of their original weight, though some will lose less and some more," says the FDA's Colman.
All of the prescription weight-loss drugs work by suppressing the appetite except for Xenical (orlistat). Approved by the FDA in 1999, Xenical is the first in a new class of anti-obesity drugs known as lipase inhibitors. Lipase is the enzyme that breaks down dietary fat for use by the body. Xenical interferes with lipase function, decreasing dietary fat absorption by 30 percent. Because the undigested fats are not absorbed, fewer calories are available to the body. This may help in controlling weight. The main side effects of Xenical are cramping, diarrhea, flatulence, intestinal discomfort, and leakage of oily stool.
Meridia (sibutramine), approved by the FDA in 1997, increases the levels of certain brain chemicals that help reduce appetite. Because it may increase blood pressure and heart rate, Meridia should not be used by people with uncontrolled high blood pressure, a history of heart disease, congestive heart failure, irregular heartbeat, or stroke. Other common side effects of Meridia include headache, dry mouth, constipation and insomnia.
Other anti-obesity prescription drugs that were approved by the FDA many years ago based on very short-term, limited data include: Bontril (phendimetrazine tartrate), Desoxyn (methamphetamine) and Ionamin and Adipex-P (phentermine). They are "speed"-like drugs that should not be used by people with heart disease, high blood pressure, an overactive thyroid gland, or glaucoma. These drugs are approved only for short-term use, such as a few weeks.
"There is no magic pill for obesity," says David Orloff, M.D., director of the FDA's Division of Metabolic and Endocrine Drug Products. "The best effect you're going to get is with a concerted long-term regimen of diet and exercise. If you choose to take a drug along with this effort, it may provide additional help."
Prescription weight-loss drugs are approved only for those with a BMI of 30 and above, or 27 and above if they have other risk factors, such as high blood pressure or diabetes.
People should contact a doctor before using any kind of drug, including a weight-loss drug.
Until recently, weight-control drugs containing the active ingredient phenylpropanolamine (also used as a nasal decongestant) were available over-the-counter (OTC). However, based on evidence linking this ingredient to an increased risk of bleeding in the brain (hemorrhagic stroke), the FDA asked drug manufacturers to discontinue marketing products containing phenylpropanolamine. In addition, the FDA issued a public health advisory in November 2000, warning consumers to stop using products containing this ingredient.
The FDA is proposing to classify phenylpropanolamine as "not generally recognized as safe" and is proceeding with regulatory actions that will likely remove this ingredient from the market. Although cough-cold products were reformulated using other nasal decongestant ingredients, there is no currently available active ingredient that is generally recognized as safe and effective for use in an OTC weight-control drug product.
Some dietary supplement makers claim their products work for weight loss. These products are not approved by the FDA before they are marketed. Under existing laws, manufacturers have the responsibility for ensuring that their dietary supplement products are safe and effective.
Many weight-loss products claim to be "natural" or "herbal," but this does not necessarily mean that they're safe. These ingredients may interact with drugs or may be dangerous for people with certain medical conditions. If you are unsure about a product's claims or the safety of any weight-loss product, check with your doctor before using it.
"Losing weight requires major lifestyle changes, including diet and nutrition, exercise, behavior modification, and--when appropriate--intervention with drug therapy," says Judith S. Stern, Sc.D., professor of nutrition and internal medicine at the University of California, Davis, and vice president of the American Obesity Association. "But it is always worth making the effort to improve your health."
Linda Bren is a staff writer for FDA Consumer.
The cabbage soup diet, the low-carbohydrate and high-protein diet, and other so-called "fad" diets are fundamentally different from federal nutrition dietary guidelines and are not recommended for losing weight.
Fad diets usually overemphasize one particular food or type of food, contradicting the guidelines for good nutrition, which recommend eating a variety of foods from the Food Guide Pyramid. These diets may work at first because they cut calories, but they rarely have a permanent effect.
A high-protein diet is one fad diet that has remained popular over the years. "High-protein items may also be high in fat," says Robert Eckel, M.D., professor of medicine at the University of Colorado Health Sciences Center in Denver. High-fat diets can raise blood cholesterol levels, which increases a person's risk for heart disease and certain cancers.
High-protein diets force the kidneys to try to get rid of the excess waste products of protein and fat, called ketones. A buildup of ketones in the blood (called ketosis) can cause the body to produce high levels of uric acid, which is a risk factor for gout (a painful swelling of the joints) and kidney stones. Ketosis can be especially risky for people with diabetes because it can speed the progression of diabetic renal disease, says Eckel.
"It's important for the public to understand that no scientific evidence supports the claim that high-protein diets enable people to maintain their initial weight loss," says Eckel. "In general, quick weight-loss diets don't work for most people."
Department of Health and Human Services'
Small Steps program
Tools and information for eating better and living a healthier lifestyle
National Institute of Diabetes and Digestive and Kidney Diseases
National Heart, Lung, and Blood Institute
Report of the FDA's Working Group on Obesity, 2004
American Dietetic Association
(800) 877-1600, or (800) 366-1655 for recorded food/nutrition messages
National Weight Control Registry
(800) 606-NWCR (606-6927)
This study gathers information from people who have successfully lost weight and kept it off. The registry would like to hear from anyone 18 or older who has lost at least 30 pounds and maintained that weight loss for at least a year.
Pub No. FDA 04-1303C
The BMI ranges for adults are shown in this chart. They are not exact ranges of healthy and unhealthy weights. However, they show that health risk increases at higher levels of overweight and obesity. Even within the healthy BMI range, weight gains can carry health risks for adults.
The chart shows heights (without shoes) ranging from 4 feet 10 inches to 6 feet 6 inches on one axis, and weights (without clothes) from 50 pounds to 275 pounds on the other axis. The range of Body Mass Index (BMI) from 18.5 to 30 is shown on the chart so that if you find the point where your height and weight intersect you can determine your BMI.
You can more simply use the interactive BMI calculator at www.nhlbisupport.com/bmi/bmicalc.htm.
(Source: Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2000.)
This is a mirror of the page at http://www.fda.gov/fdac/features/2002/102_fat.html
See also Ways to Win at Weight Loss (FDA Consumer, May 1999)