The concept of negative or zero-calorie foods, while popular on diet platforms, remains a topic of debate. The premise suggests that our bodies expend as much energy, if not more, digesting certain fruits and vegetables than the energy they provide.

However, there is no scientific backing for this notion. Even the foods lowest in calories, like celery and watercress, contain essential energy for their digestion.

In 2019, a researcher at the University of Alabama conducted a study involving celery and a bearded dragon. You can read the study here. Although the choice of a reptile may seem peculiar, bearded dragons have an omnivorous diet and a digestive process akin to humans.

The large lizard consumed 5% of its body weight in celery. Researchers monitored metabolic rates, gathered fecal and urinary samples, and assessed energy expelled through excretion.

The findings revealed that lizards only utilized about three-quarters of the energy provided by celery, which challenges the idea of negative calorie foods.

Nonetheless, some nutrition experts contend that emphasizing calorie count is not the best strategy for weight management, as the body employs different biological processes for digesting various food types.

For example, our bodies expend considerably more energy breaking down proteins compared to fats and carbohydrates, which are more easily accessible for energy. Thus, the type of food is more crucial than merely the calorie content.

Ultra-processed foods are often high in fats and carbohydrates, offering quick satisfaction but packing a lot of energy, much of which gets stored in fat cells.

In contrast, whole foods, particularly those rich in protein and fiber, generally require more energy for digestion than their processed counterparts.

Fruits and vegetables, often branded as negative or zero-calorie foods, are vital components of a balanced diet.

However, relying solely on these could deprive you of essential nutrients and lead to significant hunger and frustration.

This article addresses the inquiry (from Dani Sherman via email) regarding “Are Negative Calorie Foods Real?”

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