The Plastics know all about calorie counting.
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  • The CICO diet is gaining popularity on Reddit.
  • Short for “Calories In, Calories Out,” it has positive and negative aspects.
  • Counting calories works, but it is not necessarily a long-term healthy-eating solution.
  • Food quality and quantity are both important for maintaining a healthy diet and weight.

Calories are often demonized, with diet culture promoting the slashing, burning, and obliterating of these numbers. Losing weight will always be linked with calories, even though you need energy from calories to survive.

Manipulating this energy is the thought process behind the CICO diet that is gaining popularity on Reddit. CICO, which stands for calories in calories out, goes back to old-school dieting principles.

Experts agree that the general concept of cutting calories can help you lose weight, but there are a few red flags that pop up with the CICO diet.

Here’s everything you need to know about the diet and why it might not be a long-term healthy-eating solution.

The main idea is that you can lose weight if you eat fewer calories than your TDEE.

The basic principle behind the diet has some merit. The Reddit CICIO postdescribed the technique as eating less than your total daily energy expenditure(TDEE) or the total number of calories you burn each day.

Registered dietitian Lisa DeFazio told INSIDER that cutting calories like this is the main idea behind weight loss and that this approach could help you lose weight if done properly.

“I’ve seen a lot worse diets out there, and this surprisingly does make scientific sense,” she said. “You can experiment with yourself, eat your regular diet, calculate the calories, and then just cut 500 calories a day. That’s pretty much the key to weight loss.”

DeFazio said that calculating calories can be good for people trying to lose weight especially, because most people don’t realize how much food they really eat.

The biggest red flag with this approach, however, is focusing only on the numbers.

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Quality and quantity are both important.
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Although calories are an important factor in weight loss, registered dietitian nutritionist Malina Linkas Malkani, media spokesperson for the Academy of Nutrition and Dietetics and creator of the Wholitarian Lifestyle, told INSIDER that the quality of what you eat is key for long-term weight management and overall health and wellbeing.

“When people focus solely on a number of calories per day but eat only junk, they can end up suffering from a long list of issues,” Malkani said.

These issues include nutrient deficiencies, a loss of lean body mass (which can lower metabolism), fatigue, hormonal imbalances, bad moods, gastrointestinal functions, skin problems, compromised immunity and poor sleep, according to Malkani. DeFazio agreed, and added that eating junk food while cutting calories can lead to other issues like high cholesterol and heart disease.

“Being thin doesn’t ensure health, and I think that’s really a key thing people get confused on,” she said. “There’s always a focus on people that are very overweight, but thin people have heart attacks too.” This point goes back to the importance of overall health, not just the number on the scale.

Cutting calories only works for so long and won’t necessarily help you develop long-term healthy habits.

nutrition facts calories
Weight loss is about numbers, but overall health is more complicated than that.

Malkani said the CICO diet is not only a short-term solution that could lead to health issues if done improperly, but it likely won’t work well over time.

“In the long term […] it’s highly likely that negative health outcomes will multiply and intensify, and that weight loss will slow down on the CICO diet, as the metabolic rate changes over time with changes in the body,” she said.

Over time, DeFazio said that cutting calories will lead to your maintenance weight. For some, it might lead to a plateau before hitting that goal number. Note that trying to lose weight while already at a healthy weight will be more difficult since your body needs whatever calories it receives, according to DeFazio.

“Sometimes, people have unrealistic expectations of what a healthy weight should be,” DeFazio said. “It will go until you reach your healthy weight, and then you stay at that calorie level.”

Once you reach your goal weight, the next step is maintaining it. According to DeFazio, people often think they can eat more after losing weight, which is not the case.

This goes back to the overarching issue of the CICO diet. Cutting calories can help you lose weight if you eat healthily. Once you reach that number, however, keeping it off requires implementing other healthy practices like regular exercise, a nutrient-dense diet, and an average amount of calories. Weight loss might be a numbers game, but overall heath is more complex than that.