When we're trying to lose weight, it's very much a numbers game of calories eaten versus calories burned.
A great asset in the weight loss battle is, so-called, negative calorie foods; these are foods that burn more calories than they contain. A recent study confirmed that celery is one of these negative calorie foods.
Scientists from University Hospitals Coventry and Warwickshire NHS Trust and the University of Warwick placed Matt Tebbutt of Channel 4's Food Unwrapped in a metabolic chamber, which measured the calories ingested and burned while he ate celery in various forms over a period of 12 hours.
After being fed both celery raw and in a smoothie – each containing 53 calories — Tebbutt burned 72 calories while eating the raw celery and 112 while drinking the smoothie. In both cases, he burned more calories digesting the celery than the celery contained.
Foods like celery contain fewer calories than it takes the body to digest them, hence negative calorie foods. But is it really that simple? "Negative calorie foods can help your body burn fat and lose weight. They can boost the rate at which your body burns calories, both temporarily and in the long run. And they can help you feel full after you eat them - so you actually eat less food overall," wrote celebrity chef Rocco DiSpirito in his book The Negative Calorie Diet: Lose Up To 10 Pounds In 10 Days With 10 All You Can Eat Foods. Examples of these foods include almonds, apples, berries, celery, citrus fruits, cruciferous vegetables (broccoli, cabbage, cauliflower), cucumber, green leafy veggies, mushrooms, and nightshades.
We spoke to DiSpirito who explained that "negative calorie foods are great for weight control or a healthy lifestyle because they fill you up before they make you fat. If it is not processed food and it's eaten in its whole natural state, there is a good chance it is a negative calorie food. One of my favorites is water! It contains no calories yet burns one calorie per ounce consumed. It's like a magic trick!"
But don't get too excited quite yet. "Here's the thing: When we estimate how many calories a person needs, we are taking into account their Basal Metabolic Rate (BMR). This already includes how many calories we burn digesting our food. While you might burn a few extra calories eating foods such as celery or grapefruit (another negative calorie food), this won't replace an exercise regimen. You'd have to eat a TON of celery to get any sizeable calorie burn. Instead, eat foods like celery because they are low-calorie foods to fill up on and when you're full, you're less likely to eat the higher calorie foods like cookies or pizza. Another good celery trick- use it does dip into hummus, guacamole or a homemade Greek yogurt dip and swap out the chips." says Alix Turoff, RD of Top Balance Nutrition in New York City.