"People who have difficulty controlling their weight tend to have inherently slow 'metabolisms.'"

Although some earlier scientific studies incorrectly made such a conclusion,1 more recent and better-designed studies have generally found that obesity-prone individuals have resting metabolic rates as fast as those of other people with similar muscle and organ mass.1,2 Studies show that even in infancy3 and youth,4 excess weight gain is generally a result of excess eating rather than a slow metabolism. The incorrect conclusions of some earlier studies are at least partially due to the tendency of obese individuals to underestimate the number of calories they consume by 20 to 50%.5,6,7 This tendency to underestimate the number of calories eaten may result in part from irregular eating habits, such as skimping on breakfast or lunch and then eating unhealthy snacks or binging at dinner, drinking "energy" or soft drinks between meals, snacking at bedtime, etc.

Gaining weight actually increases one's resting metabolic rate because of the extra calories required to maintain the added tissue and to function with the additional body weight. If you are overweight, therefore, you probably currently have a faster metabolic rate than people of similar frame size who are not overweight. Such an increase in metabolic rate will tend to work against additional weight gain and stabilize your weight unless you eat even more daily calories than before.

"Some people are genetically fat."

In fact, we are all "genetically fat" when in an obesigenic (obesity-promoting) food environment and living a sedentary lifestyle. Accumulating body fat under such conditions is the expected result of normal genes functioning correctly.

It is our food environment and lifestyles that are broken, not our genes.

There are genes that are statistically associated with having more body fat or having greater difficulty in losing it. However, only a few obesity-related genes have major effects on body fat. These genes are rare and generally act by increasing one's proclivity to overeat.10 Most obesity-related genes have relatively minor effects. These genes may act by increasing one's proclivity to overeat, reducing one's proclivity to be physically active, or by some unknown mechanism.10,12 There is very little evidence for important obesity-related genes that act by reducing one's resting metabolic rate.12 The influence of genes with minor effects can be made inconsequential by making minor adjustments in one's food environment, eating habits, and/or level of physical activity.

Some groups of people, such as the Pima Indians of the United States and Mexico, are believed to have more than their share of these obesity-related genes. However, even this group should not be considered "genetically fat." While the Pima living in the United States are among the most obese populations in the world, the Pima living in remote areas of Mexico, where the environment is physically demanding and more traditional foods are eaten, are lean like non-Pima Mexicans living in the same environment.13

In summary, genes with major effects on your ability to control your body fat are rare. Genes with minor effects are more common. Although these genes may make weight loss more difficult, they cannot make you gain fat if you are not eating excess calories, or stop you from losing it if you maintain a calorie deficit.

We all have genes that are designed to store extra calories as fat. The best way to prevent your genes from causing an accumulation of fat is to remove yourself from the ambient obesigenic environment and sedentary lifestyle and to create a more suitable personal food environment14 and physically active lifestyle.

"Some people are genetic 'endomorphs', and therefore naturally plump and rounded."

Although individuals may be naturally short, stocky, or muscular, no one is naturally fat. The primary purpose of body fat is to store energy in times of excess so that it is available for retrieval in times of need. Fat that is a permanent part of a person would be unavailable in times of need, and therefore counter to this purpose. See the "Some people are genetically fat" section above for additional discussion of this topic.

"Gaining weight is a natural part of aging."

Not true. Whatever your age, the only way to gain fat is to eat more calories than you burn. Older people tend to have more fat than younger people for the same reason that they tend to have more money: they have had more time to accumulate it. Also, most of us live in a more obesigenic food environment and are less physically active than in our younger years.

Although the resting metabolic rate of most adults slows with age due to loss of muscle and organ mass,15a this slowing can be largely averted or even reversed with strengthening15b,16,17 and endurance18,19 exercises. Alternatively, older adults who don't want to go to the effort of keeping their metabolisms up can prevent weight gain by reducing calorie consumption proportionately to match their slower metabolisms.

"Everyone has a natural weight that their body returns to when they are not dieting."

No, you do not have a single "natural weight." The amount of body fat that is "natural" for you depends primarily on your daily calorie consumption and level of physical activity. If you start eating more calories per day while maintaining the same level of physical activity, your body will gain fat until it reaches a new "natural" point that is stable.

This point will be reached when your daily metabolic rate (the number of calories your body burns each day) increases enough to equal the number of calories you eat each day. As you gain more and more fat, your daily metabolic rate increases as a result of two processes. First, with the extra weight on your body, everyday tasks become more difficult, causing more calories to be burned as you perform these activities. Second, as you gain weight, you develop more muscle mass to heft around the extra weight. More calories are required to maintain this extra muscle, as well as to maintain and function with the extra fat, even when you are at rest. These extra calorie requirements result in an increase of your resting metabolic rate.

Eventually, the increasing weight will cause your daily metabolic rate to increase enough to cancel out the additional calories, and you will stop gaining weight.

If you become concerned with your expanding waistline, and start eating a little less, you will reach your stable weight even sooner. If, on the other hand, you make even greater increases in your calorie consumption, the stable point will take longer to reach, or may not be reached at all before you die.

Similarly, if you make a habit of consuming substantially fewer calories each day, you will lose weight (both fat and muscle) until your daily metabolic rate decreases to a point that it matches your new level of daily calorie consumption.

"Being slim means being hungry."

Not with good eating habits. Eating 4 to 6 small balanced meals per day, and keeping food out of sight between meals, should eliminate most substantial feelings of hunger. A properly balanced meals includes some protein and fat, as well as carbohydrates in the form of vegetables and course whole grains. Foods made of processed grains or added sugars should be avoided or eaten in smaller amounts. The combination of fat, fiber, protein, and relatively intact tissue structure of such meals provides longer satisfaction after the meal ends. Avoiding sugars and refined starches, as well as avoiding snacks and the sight of food between meals, helps prevent unnecessary cravings.

"If it says 'granola bar' or 'energy drink' it must be good for you."

Not if the first ingredient is a sugar (such as sucrose, maltose, brown sugar, glucose, honey, or corn syrup), or if two of the first three ingredients are sugars. Sugars supply energy (i.e. calories) but little else. If you are overweight, you are already consuming too much energy.

"You can never be as slim as before you had children."

You don't have to look too hard to find women who have proven this belief wrong. Fat gained during pregnancy can be lost like any other fat, by adjustments in eating and exercise habits. It can also be lost by breast feeding, which can use 400 to 500 calories per day. Abdominal muscle tone that was lost can be improved with strength exercises such as crossover crunches, abdominal vacuums and kegel exercises.

"Eating healthy means not being able to have dessert."

Sweets and other unhealthful foods can be eaten every day, or even every meal, as long as they are eaten in smaller portions. Smaller portions, when eaten slowly to savor every part, can bring as much pleasure as larger portions.

"Carbs should be eaten separately from protein or fat."

This advice was shown to be unhelpful in a recent study.20

"For losing weight, the less fat you eat, the better."

Only up to a point. As far as your weight is concerned, the main problem with fat is that it is calorie dense. A cup of vegetable oil, for example, has more than twice the number of calories as a cup of sugar. Fat is not all bad, however. A little fat in your meal may help keep you satisfied longer by slowing the digestion of carbohydrates. Fat can also make food taste better. As a result, a diet that includes a moderate amount of fat can be easier to stick with over the long term, resulting in more weight loss than would occur on a very low fat diet. In other words, extremely low fat diets seem to encourage cheating or giving up altogether.21,22

Some people mistakenly believe that fat-free or low-fat foods will not make them "fat." Excess calories from any source -- whether fat, protein, or carbohydrate -- will be stored by the body as fat.

"'Miracle' supplements make losing weight much easier."

Once thing that makes Fat Loss Facts different from most other weight loss web sites is that we don't sell anything. The reason is simple. Extra body fat is caused by extra calories, and in order to remove it, you need to eat less or burn more. You don't need a miracle supplement or drug for that, just correct information and the determination to use it to live a healthier lifestyle.

Put down your credit card and do a little independent research before you buy any "miracle supplement." Words like "detoxify," "purify," "cleanse," "miracle," "ancient," "sacred," "organic," and "amazing" are more often used by marketers than by scientists or medical professionals. Do you really trust someone who wants you to buy an expensive product more than you trust mainstream medical research or your own doctor? Do you really believe that something out of a bottle can substitute for healthful eating and a physically active lifestyle? Supplements are great for making or losing loads of money, but for optimal health, a balanced diet and exercise will probably be sufficient. When it comes to expensive nutritional supplements, a little skepticism can save you money, time, and maybe even your health. The FDA23 and FTC24 have web sites with some excellent tips and resources for evaluating claims about nutritional and dietary supplements. Quackwatch.Org25 also lists some useful resources for investigating extraordinary claims. If you are still unsure, ask your doctor about it.

"How fat you are depends on the kind of bacteria in your gut."

Recent scientific studies26 have been interpreted this way by some. What the studies really suggested was that "bad" bacteria can add up to about 2 percent more calories to your meal by digesting components of your food for you that you would otherwise be unable to digest. This amounts to 20 to 50 calories per day, worst case, for most adults. Most of us need to decrease the amount of food we eat each day by 10 times that amount or more. The effect of the bacteria then, is comparatively small. The studies also showed that obese individuals who lose weight also lose much of the "bad" bacteria. This suggests that the abundance of bad bacteria is perhaps more a result of excess fat or of overeating than it is a cause of excess fat. Regardless, you will be better served by not eating a cookie than by worrying about whether the number of digestible calories it contains is 100 or 102.