Editor’s Note: This post was updated on November 20, 2018 for accuracy and comprehensiveness. It was originally published on March 31, 2016.
Making a change in body composition comes down to focusing on two different areas: Gaining Lean Body Mass and losing fat mass. With obesity rates at an all time in this country, its the latter that many people struggle with. That’s because losing body fat is hard and requires that you maintain tremendous disciple. So it’s natural that people want to find some way to make it easier.
In theory, losing fat is straightforward: You need to be in a caloric deficit (which means eating less than your body demands, increasing your energy output, or probably both), and it’s going to take longer than you might want.
It sounds simple but its requires a lot of grueling hard work. People naturally want to find a way to make it easier. That why there are so many fat loss myths out there and whole cottage industry of misleading products, articles, and “gurus” to support them.
We want to help to dispel these myths and make sure you don’t waste your time and energy. Let’s take a look at some of the worst offenders and see what science has to say about them.
To Lose Fat, All You Have To Do Is Work Out
You might start your weight loss journey by signing up for a gym, which is a great start, but if you neglect your diet it’s ultimately a waste of your energy.
You see, fat loss occurs as the result of being in a caloric/energy deficit. That means you have to take in less calories than your body is using. According to the Centers for Disease Control, you need to reduce your food intake by at least 500 calories a day to lose around a pound of body fat per week.
Here’s the problem: if you start increasing your workouts at the gym, you body will instinctively want to increase its caloric intake. If you eat more calories than you burned, you are wasting your workout.
Let’s say your body needs a 2,100 calorie diet to maintain its weight, and on a normal day, you eat 2,100 calories. Your weight won’t change much, if at all. Now let’s say you burn 300 calories from a workout; now your body needs 2,400 calories to maintain weight. If you make no change to your diet, you’ll be in a -300 caloric deficit. But if you start increasing your caloric intake because you think “your metabolism is speeding up” (which is not how it works, by the way), you’ll negate any energy deficit you worked for, leading to no fat loss.
If You Eat At Night, You Get Fat
Intuitively, this make sense. If you eat a bunch of food and then go to sleep, your body turns it all into fat because you’re not moving around and using it. Just like a bear in winter, right?
This type of thinking ignores a basic physiological process: your metabolism, which is more formally known as your Basal Metabolic Rate. Your BMR is the amount of calories that your body consumes over a 24-hour period at rest, and according to the CDC, it’s the amount of calories you burn over a 24-hour period that affects your weight. That includes when you sleep.
Let’s say your BMR is 1,600 calories/day. That means your metabolism is burning roughly 67 calories per hour, which multiplied by 8 for an 8-hour sleep is a little over 533 calories.
This means that if you eat a meal right before sleeping, it’s much more important about how much you ate rather than when. If your daily caloric intake to maintain weight is 2,100 and you decide to have a 200-300 calorie snack before sleeping when you’ve already eaten 2,100 calories that day, then yes, you will likely gain weight. But if you’re watching your caloric intake and a 200-300-calorie snack is still within your limits, you will be fine.
You Can Go On A “Detox”, “Juice Cleanse”, or “Juice Fast” To Lose Fat
The myth that a juice cleanse can help with weight loss has so much staying power because it involves something people know they don’t do enough of: eat fruit and vegetables.
Juice cleanses promise to detox harmful “toxins” from your body, which are blamed for causing everything from tiredness, sluggishness and poor health to of course weight gain.
Juice cleanses are incredibly expensive – one company sells a 3-day detox regimen for nearly $200 – and are incredibly ineffective at producing lasting weight loss. Furthermore, there is virtually no peer-reviewed scientific literature supporting the benefits of a detox. Furthermore, you also won’t find any established organization like the CDC, Mayo Clinic, or US Department of Agriculture promoting them either. Instead, you’ll find these organizations expressly discouraging them.
Why do so many people still go on a juice cleanse?
Because of what happens when you go on a 3-day ANYTHING fast: you deprive your body of essential macronutrients, causing you to go into a temporary caloric deficit as well as significantly reducing the amount of glycogen in your body. This has a significant effect on weight loss, albeit temporary weight loss.
Glycogen is an energy molecule that your body creates primarily from carbohydrates. Your body loves glycogen, and under normal circumstances is its preferred energy source. When you significantly cut carbohydrates out of your diet, your glycogen stores become depleted. So a juice cleanse is not helping your body release toxins, it’s just depleting your glycogen stores. That is why people feel like they have no energy when they are on a fast.
Reduced glycogen in your body has a significant effect on your weight because water bonds to glycogen at a rate of about 3.5 grams per gram of glycogen. Cut out the glycogen when you go on a juice “cleanse” for a couple of days and all you’ve done is mostly lose water weight, energy and lean body mass. In a couple days you’ll gain all the body weight back, along with the glycogen stores, after your expensive “detox” ends.
You Have To Go On A Low-Fat Diet To Lose Fat
Remember this picture?
This one’s a bit tricky because technically it’s partially true: cutting dietary fat out of your diet will cause you to lose body fat if it causes you to be in a caloric deficit, but that’s only because cutting anything out of your diet will also cause you to lose fat too, regardless of the nutrient source. Dietary Fat alone doesn’t make you any fatter than carbs or protein do. Yet, a stigma against dietary fat still exists.
This a shocker for many because anyone born after 1980 has never lived in a world where the promotion of a high-carbohydrate, low-fat diet wasn’t a standard dietary recommendation from the US government. A plate dominated by pasta might have been a recommended weight loss meal.
That’s because in 1977, a controversial set of well-intention dietary recommendations explicitly linked certain nutrients like dietary fat to a whole host of dangerous diseases including heart disease, cancer, obesity, and strokes. In a effort to reduce the prevalence of these diseases, the high carb/low fat diet was introduced and officially recommended by the US Department of Agriculture.
Americans, following their government’s advice, began to eat replace fat with carbohydrates in their meals. What followed was a sharp, 20+ year rise in obesity.
In 2010, researchers in the journal Nutrients published a study bemoaned the fact that some controversial positions – such as the demonetization of fat – had been allowed to persist unproven for 30 years and reappear in the 2010 Dietary Guidelines for Americans.
5 years later, their concerns were finally heard. When the guidelines went through their scheduled revision, the 2015 guidelines both lessened the recommendations for carbs and increased those for fat while waiving the ban on dietary cholesterol altogether.
Does this mean that you can eat as much French fries, fried foods, and every other delicious fat-filled treat and expect to avoid health problems? Of course not. There is still such a thing as good and bad types of fat. Trans fat is still super bad. But this does mean that outright cutting out all fat from your diet isn’t always necessary.
While cutting fat is a good way to reduce overall caloric consumption (at 9 calories per gram, fat is the most calorie-dense macronutrient), what’s more important for most people is to try to stay within their recommended daily caloric intake and not take drastic dietary steps like significantly reducing or eliminating an entire nutrient group.
Oh, and the food pyramid? It actually doesn’t exist anymore.
You Can Burn Fat By Targeting It With Exercise
The myth that you can target body fat with targeted muscle gain, despite a significant amount of scientific literature saying otherwise is something many people wish could be true because it touches on a major problem that many people have: “How do I get rid of this belly fat?!”
Like juice cleanses and detoxes, this myth has created an endless supply of articles – like this one from Health.com – supporting the myth that spot reduction through targeted strength/resistance training can burn fat in a specific area.
That’s not entirely accurate. Strength and resistance training is helps with muscle gain, not necessarily fat burning. The more crunches you do, the bigger and stronger your abs will be; but you won’t get any closer to actually seeing abs without reducing your body fat percentage.
Does this mean the energy you spend developing your muscles won’t result in burning fat? No, it actually can, but the fat loss won’t be specific to the area you worked out. Increases in Lean Body Mass (which your skeletal muscle makes up a part), influence your metabolism by increasing your BMR. This means the amount of calories you’re eating plays a role as well.
So, in theory, if you increase the number of calories your body needs in a day because the muscle gain makes your hungrier, but you don’t increase your calorie intake at all, you could lose fat over time – but this is going to be a much slower/indirect process and will do nothing to target belly, arms, or any other problem area.
Don’t Waste Your Time
Extra body fat can significantly affect your self-esteem, confidence, and health. That’s why it’s so tempting to believe one or more of these fat loss myths, if they mean faster results.
Unfortunately, if you try to lose fat by following these or other myths you may have heard of, it’s going to waste time and energy and ultimately set you back.
Don’t waste your efforts. To lose fat, stick to the basics; stick to what’s been proven over and over again in the scientific literature. Proper diet and exercise might not sound like a fastest and easiest way to go, but there’s a reason why any credible trainer, nutritionist, or researcher worth their title will recommend it: because it works.
When you hear something about fat loss that sounds too good to be true, it probably is. Stick to the basics and you will see results.