During the early 1990s, scientists created an enclosed ecosystem (in a huge set of buildings) called Biosphere 2 and attempted to see if people could live in a sealed facility for two years, living on food they grew in a sustainable atmosphere. The scientists tried to recreate different environments (desert, ocean, savannah) to sustain life, and to provide oxygen, water and food.
Because of the difficulty in growing enough food for the eight researchers living in the facility, they had to eat fewer calories, but calories that came from high-nutrition foods. The results were so positive, the Calorie Restriction with Optimal Nutrition (CRON) diet was born.
In short, you eat fewer calories, but you eat Super Foods that provide all of the carbs, protein, fat, vitamins, minerals, dietary fiber and other nutrients you need. The results of this diet seem to indicate eating this way produces better weight management, improved blood cholesterol, better sleep, lower blood pressure and more energy.
Should You Try It?
Unlike many fad diets, CRON does not ask you to greatly reduce or eliminate whole subsets of foods. It’s not a short-term weight-loss plan, although you can lose weight on it based on the fact that you’re eating fewer calories. You should always check any new diet with your doctor or registered dietitian, but because of its reliance on a wide variety of healthy foods, the CRON diet might be less dangerous than other well-known fad diets.
What Foods Should you Eat?
If you’re interested in trying your own version of the CRON diet before doing more research and going on the “official” CRON eating plan, read up on Super Foods. Super Foods are those that are at the top end of providing lots of vitamins and minerals than others in their groups. For example, instead of having an 800-calorie dinner of steak, mashed potatoes, and green beans, you might have a 600-calorie dinner of salmon, sweet potatoes, and broccoli. Instead of making a salad with iceberg lettuce topped with veggies, ham and cheese, you’d eat a smaller salad made with spinach, topped with high-nutrition veggies, eggs, and walnuts.
Won’t I Be Hungry?
The key to success with any eating plan is to gradually taper your calories rather than crashing or cutting your daily food intake drastically. Eating higher-quality carbohydrates, nuts, seeds, proteins, and fats will help prevent the hunger pangs you get when you eat too many low-quality foods that contain sugars. Your body will get used to fewer calories over time (you won’t be hungry). You will feel “starved,” however, if you try to cut your daily calories from 2,000 to say, 1,400 overnight.
How Many Calories?
Check out our blog post, “How Many Calories Should You Eat Each Day?,” to learn your recommended calorie target based on your age, sex and activity level. With a CRON diet, you seek to reduce your daily calories, but still meet the same recommended daily numbers for carbs, protein, fat, vitamins, minerals and dietary fiber. It’s possible to do this by eating high-nutrition foods.
Do I Have to Go Completely CRON?
Even if you aren’t interested in following a CRON diet long term, take a look at the foods you have in your cupboard, pantry and refrigerator. Look for substitutes for those foods you think are “filler” foods that really don’t pack a high-nutrition punch. Make it a goal this year to balance your meals each day by adding more Super Foods and reducing or eliminating empty carbs, fatty proteins and sugary foods and drinks. Write a list of five basic foods you eat each week that aren’t packed with nutrients, and write down five (or more) Super Foods you want to eat more of this year. Also, read up on expanding veggie options for more suggestions.