There is a lot of weight loss advice on the internet.

Most of it is either unproven or proven not to work.

Here are the top 12 biggest lies, myths, and misconceptions about weight loss.

1. All calories are equal

The calorie is a measurement of energy. All calories have the same energy content.

However, this does not mean that all calorie sources have the same effects on your weight.

Different foods go through different metabolic pathways and can have vastly different effects on hunger and the hormones that regulate your body weight.

For example, a protein calorie is not the same as a fat or carb calorie.

Replacing carbs and fat with protein can boost your metabolism and reduce appetite and cravings, all while optimizing the function of some weight-regulating hormones (1, 2, 3).

Also, calories from whole foods like fruit tend to be much more filling than calories from refined foods, such as candy.

SUMMARY Not all calorie sources have the same effects on your health and weight. For example, protein can increase metabolism, reduce appetite, and improve the function of weight-regulating hormones.

2. Losing weight is a linear process

Losing weight is usually not a linear process, as some people think.

Some days and weeks you may lose weight, while during others you may gain a little bit.

This is not a cause for concern. It’s normal for body weight to fluctuate up and down by a few pounds.

For example, you may be carrying more food in your digestive system or holding on to more water than usual.

This is even more pronounced in women, as water weight can fluctuate significantly during the menstrual cycle (4).

As long as the general trend is going downwards, no matter how much it fluctuates, you will still succeed in losing weight over the long term.

SUMMARY Losing weight can take a long time. The process is generally not linear, as your weight tends to fluctuate up and down by small amounts.

3. Supplements can help you lose weight

The weight loss supplement industry is massive.

Various companies claim that their supplements have dramatic effects, but they’re rarely very effective when studied.

The main reason that supplements work for some people is the placebo effect. People fall for the marketing tactics and want the supplements to help them lose weight, so they become more conscious of what they eat.

That said, a few supplements have a modest effect on weight loss. The best ones may help you shed a small amount of weight over several months.

SUMMARY Most supplements for weight loss are ineffective. The best ones can help you lose a bit of weight, at most.

4. Obesity is about willpower, not biology

It is inaccurate to say that your weight is all about willpower.

Obesity is a very complex disorder with dozens — if not hundreds — of contributing factors.

Numerous genetic variables are associated with obesity, and various medical conditions, such as hypothyroidism, PCOS, and depression, can increase your risk of weight gain (5).

Your body also has numerous hormones and biological pathways that are supposed to regulate body weight. These tend to be dysfunctional in people with obesity, making it much harder to lose weight and keep it off (6).

For example, being resistant to the hormone leptin is a major cause of obesity (7).

The leptin signal is supposed to tell your brain that it has enough fat stored. Yet, if you’re resistant to leptin, your brain thinks that you’re starving.

Trying to exert willpower and consciously eating less in the face of the leptin-driven starvation signal is incredibly difficult.

Of course, this doesn’t mean that people should give up and accept their genetic fate. Losing weight is still possible — it’s just much harder for some people.

SUMMARY Obesity is a very complex disorder. There are many genetic, biological, and environmental factors that affect body weight. As such, losing weight is not just about willpower.

5. Eat less, move more

Body fat is simply stored energy.

To lose fat, you need to burn more calories than you take in.

For this reason, it seems only logical that eating less and moving more would cause weight loss.

While this advice works in theory, especially if you make a permanent lifestyle change, it’s a bad recommendation for those with a serious weight problem.

Most people who follow this advice end up regaining any lost weight due to physiological and biochemical factors (6).

A major and sustained change in perspective and behavior is needed to lose weight with diet and exercise. Restricting your food intake and getting more physical activity isn’t enough.

Instructing someone with obesity to simply eat less and move more is like telling someone with depression to cheer up or someone with alcoholism to drink less.

SUMMARY Telling people with weight problems to just eat less and move more is ineffective advice that rarely works in the long term.

6. Carbs make you fat

Low-carb diets can aid weight loss (8, 9).

In many cases, this happens even without conscious calorie restriction. As long as you keep carb intake low and protein intake high, you’ll lose weight (10, 11).

Even so, this does not mean that carbs cause weight gain. While the obesity epidemic started around 1980, humans have been eating carbs for a very long time.

In fact, whole foods that are high in carbs are very healthy.

On the other hand, refined carbs like refined grains and sugar are definitely linked to weight gain.

SUMMARY Low-carb diets are very effective for weight loss. However, carbs are not what causes obesity in the first place. Whole, single-ingredient carb-based foods are incredibly healthy.

7. Fat makes you fat

Fat provides around 9 calories per gram, compared with only 4 calories per gram of carbs or protein.

Fat is very calorie-dense and commonplace in junk foods. Yet, as long as your calorie intake is within a healthy range, fat does not make you fat.

Additionally, diets that are high in fat but low in carbs have been shown to cause weight loss in numerous studies (12).

While packing your diet with unhealthy, high-calorie junk foods laden with fat will definitely make you fat, this macronutrient is not the sole culprit.

In fact, your body needs healthy fats to function properly.

SUMMARY Fat has often been blamed for the obesity epidemic. While it contributes to your total calorie intake, fat alone does not cause weight gain.

8. Eating breakfast is necessary to lose weight

Studies show that breakfast skippers tend to weigh more than breakfast eaters (13).

However, this is probably because people who eat breakfast are more likely to have other healthy lifestyle habits.

In fact, a 4-month study in 309 adults compared breakfast habits and found no effect on weight whether the participants ate or skipped breakfast (14).

It’s also a myth that breakfast boosts metabolism and that eating multiple small meals makes you burn more calories throughout the day (15).

It’s best to eat when you’re hungry and stop when you’re full. Eat breakfast if you want to, but don’t expect it to have a major effect on your weight.

SUMMARY While it’s true that breakfast skippers tend to weigh more than breakfast eaters, controlled studies show that whether you eat or skip breakfast doesn’t matter for weight loss.

9. Fast food is always fattening

Not all fast food is unhealthy.

Because of people’s increased health consciousness, many fast food chains have started offering healthier options.

Some, such as Chipotle, even focus exclusively on serving healthy foods.

It’s possible to get something relatively healthy at most restaurants. Most cheap fast food restaurants often provide healthier alternatives to their main offerings.

These foods may not satisfy the demands of every health-conscious individual, but they’re still a decent choice if you don’t have the time or energy to cook a healthy meal.

SUMMARY Fast food does not have to be unhealthy or fattening. Most fast food chains offer some healthier alternatives to their main offerings.

10. Weight loss diets work

The weight loss industry wants you to believe that diets work.

However, studies show that dieting rarely works in the long-term. Notably, 85% of dieters end up gaining the weight back within a year (16).

Additionally, studies indicate that people who diet are most likely to gain weight in the future.

Thus, dieting is a consistent predictor of future weight gain — not loss (17).

The truth is that you probably shouldn’t approach weight loss with a dieting mindset. Instead, make it a goal to change your lifestyle permanently and become a healthier, happier, and fitter person.

If you manage to increase your activity levels, eat healthier, and sleep better, you should lose weight as a natural side effect. Dieting probably won’t work in the long term.

SUMMARY Despite what the weight loss industry would have you believe, dieting usually doesn’t work. It’s better to change your lifestyle than to hop from diet to diet in the hope of losing weight.

11. People with obesity are unhealthy and thin people are healthy

It’s true that obesity increases your risk of several chronic illnesses, including type 2 diabetes, heart disease, and some cancers (18, 19, 20).

However, plenty of people with obesity are metabolically healthy — and plenty of thin people have these same chronic diseases (21).

It seems to matter where your fat builds up. If you have a lot of fat in your abdominal area, you’re at a greater risk of metabolic disease (22).

SUMMARY Obesity is linked to several chronic diseases, such as type 2 diabetes. However, many people with obesity are metabolically healthy, while many thin people are not.

12. Diet foods can help you lose weight

A lot of junk food is marketed as healthy.

Examples include low-fat, fat-free, and processed gluten-free foods, as well as high-sugar beverages.

You should be skeptical of any health claims on food packaging, especially on processed items. These labels usually exist to deceive — not inform.

Some junk food marketers will encourage you to buy their fattening junk food. In fact, if the packaging of a food tells you that it’s healthy, there’s a chance it’s the exact opposite.


Oftentimes, products marketed as diet foods are junk foods in disguise, as they’re heavily processed and may harbor hidden ingredients.

The bottom line

If you’re trying to lose weight, you may have heard a lot of the same myths. You may have even believed some of them, as they’re hard to avoid in Western culture.

Notably, most of these myths are false.

Instead, the relationship between food, your body, and your weight is very complex.

If you’re interested in weight loss, try learning about evidence-based changes you can make to your diet and lifestyle.