Negative calories are a concept based on the idea that some foods have a calorie count that’s smaller the calories used by your body to digest and metabolize them. Therefore, eating them would be like exercise, helping you lose weight as you eat.

Since there are many diets that use the concept of negative calories, it’s important to know more about it, so you can separate actual scientific data from simple misconception. Here are the 10 things you should know about the negative calorie food myth, from the explanation of what a calorie actually is to negative-calorie beverages.

1. Understanding Calories

Measuring the amount of energy required to produce heat, the term calorie is used for food to signify the amount of stored energy you’ll get once you eat it. If the energy isn’t consumed by your body completely, it either exits the body through the digestive system, or it sticks around, as a fatty deposit.

Negative Calorie Foods Myth

2. The Thermic Effect of Food Explained

Since your body doesn’t have direct access to the energy stored in food, it need to use calories in order to digest it in order to be able to use it. The thermic effect of food is usually linked to 5 to 10% of the energy stored in what you’re eating. One of the things you should know about the negative calorie foods myth is that the thermic effect should be over 100% in order for the term “negative” to actually be accurate.

3. Negative Calorie Foods Exist… In Theory

While negative calorie foods may exist, we haven’t found them yet. When a food it labeled as having negative calories, the true meaning is of it is that it has a low calorie content. However, the calories that remain after your body uses up to 10% for digestion, are still positive.

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4. Are There Zero-Calorie Foods?

You won’t find zero calorie foods that weren’t produced in a lab. The only natural element that has zero calories is water. Artificial sweeteners have been designed to deliver 0 calories, but unless you’re eating a plate of Aspartame for lunch, one of the things you should know about the negative calorie foods myth is that every food that isn’t completely synthetic has “positive” calories.

Artificial Sweetener Aspartame

5. Low-Calorie Foods Are Still Good for Weight Loss

Many foods have been labeled as negative-calorie, when they’re actually low calorie. The most often included in a negative calorie foods list include: apples, asparagus, beets, broccoli, cabbage, cauliflower, celery, cucumbers, garlic, grapefruit, lemons, lettuce, onions and turnips.

6. Negative Calorie Diets Are Playing You for a Fool

One of the most important things you should know about the negative calorie foods myth is to be wary of any diets that use the term. Even if they explain that they actually mean very low calorie foods, they’re hoping to make you spend money on books that aren’t advertised honestly.

7. You Don’t Need Negative Calories, But Foods That Boost Your Metabolism

When you’re trying to lose weight, you should be focused on foods and exercise that boost your metabolism, instead of trying to find the negative calorie food that you can eat anytime. Vegetables and fruits that are high in fiber and low in calories are your best best for a food that has a positive effect on your metabolism even when eaten in large quantities.

8. Zero-Calorie Drinks Still Include Positive Calories

Every beverage that’s advertised as a zero calorie drink has a few calories. This is one of things you should know about the negative calorie foods myth, along with the fact they often lack any actual nutrition. If you’re looking for low-calorie foods and drinks, vegetables and fruits are your best bet, eaten whole, not just the juice with has less fiber but all of the sugar.

Enviga Calorie Burning Drink Banned

9. Coca-Cola and Nestle Tried to Market a Negative Calorie Drink

The Coca-Cola Company and Nestlé had to pay a $650,000 fine in 2007, after being sued for claiming that their green tea drink, Enviga, burned up to 33 calories more than it delivered in a 12-ounce can. It didn’t, but it did contain stimulants like caffeine.

10. The One True Negative Calorie “Food” Is…

Ice cold water! One of the things you should know about the negative calorie foods myth is that a glass of ice water has a negative quality of 8.8 kcal. This doesn’t mean much though, as drinking one glass a day for a year will only help you lose a single pound.

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