It’s the Latest Diet Craze, But Is It Safe?

A nutritional fad called CICO – short for “Calories In, Calories Out” promises you can eat whatever you want, junk food included, and still shrink your waistline – as long as every day you expend more calories than you consume.
It’s a simplified approach to eating that essentially views fruits and vegetables through the same prism as candies and soda. All that matters is the total caloric tally.

Perhaps not surprisingly, many nutritional experts disagree. “Be healthy isn’t just about weight loss alone,” noted Lona Sandon, program director and assistant professor of clinical nutrition at the University of Texas Southwestern Medical Center in Dallas. “You have to consider the whole package.”

Sandon acknowledged that those who adopt a CICO approach to eating “might actually lose weight.” But there’s a downside: “nutrient deficiencies or even malnutrition,” she warned.

“You may not be providing all the nutrients your body needs if you are not paying attention to the types of foods you are putting in your body,” Sandon Said. “This could mean osteoporosis later in life, increased risk of cancer, heart disease, etcetera.”

Dietitian Connie Diekman added, “Weight loss, in an unhealthy way, is never a good idea.” She’s director of university nutrition at Washington University in St. Louis. “Managing calories to achieve weight loss is important, but if important nutrients are missing, then muscle mass will decline, bone health, mental acuity and many other essential functions will be compromised,” Diekman said.



My Take:
The industry standard textbook for nutritional education is Perspectives in Nutrition by Wardlaw and Hampl. The chapter on energy balance and weight control contains a formula for the “estimated energy requirements” or EER. Using age, weight, height and physical activity you can determine one’s EER. This this the caloric intake needed to maintain your current weight. If you subtract 400 Kcal from this total, theoretically, you will experience a slow but steady weight loss.

However, the formula rarely works because the quality of foods is vital to healthy weight loss. Junk food is very high in calories but very low in nutrients. By contrast, fruits and vegetables are generally very low in calories but nutrient dense.

Based on CICO, a 40 year-old male who is sedentary has an EER of 1800 Kcal. A daily diet of 1400 Kcal will result in weight loss. However, a cup of white rice is over 700 Kcal and one slice of pie is 400-700 Kcal. You’ve reached your daily intake with just these two items. Again, by contrast, an apple is 81 Kcal and a banana is 105 Kcal. The veggies are even lower – a cup of carrots is 48 Kcal and a cup of green beans is 110 Kcal. If you stick to the fruits and vegetables, you have eaten your fill before ever reaching 1400 Kcal.

Unfortunately, even combining CICO with healthy foods doesn’t guarantee weight loss. Approximately 25% of all caloric burn is thermogenic and based on your metabolism. If your metabolism is impaired, this factor skews the math to the point that the caloric intake need to be so low that the body stores fat as a response to the obvious lack of food in the environment. It will actually breakdown healthy organs and muscle to feed the body rather than burn the fat.

The Bottom Line:
CICO has some value as a general guideline for caloric consumption. The benefits of daily exercise do dramatically improve the effects of CICO. However, the need for nutrient dense, low calorie food (fruits and vegetables) is vital to obtain your optimal weight. Finally, metabolic factors from years of poor diet and exercise habits impair the success of any weight loss program.

Source: November 22, 2017 National Institutes of Health