CICO Diet: Guidelines, Foods, Benefits, Risks

Energy balance is the basic principle of weight loss, and for decades, it has been the foundation of the CICO diet. The “calories in, calories out” diet is a weight management approach centered on the theory that eating fewer calories than you burn will result in weight loss. It’s known for its flexibility, allowing individuals to consume any food in any portion size as long as it fits within their calorie deficit goals.

While this straightforward approach may appeal for various reasons, research has shown that sustainable weight loss is much more involved. Tracking calories can certainly support weight loss efforts, but it may not be appropriate for everyone.

Calories are a measurement of the energy derived from food and beverages, which the body uses as fuel to perform its biological functions. The balance between calories consumed and calories expended can influence body weight. Consuming more calories than you burn results in weight gain, while burning more calories than you eat results in weight loss.

People following the CICO diet to lose weight typically try to eat within a calorie deficit, meaning they aim to burn more calories than they consume.

Research on optimal weight loss strategies supports this concept, showing that a consistent calorie deficit can result in weight loss over time. However, as your weight trends down, your energy needs adjust, requiring a tighter calorie deficit.

The CICO diet for weight loss involves managing your calorie intake to reach a calorie deficit. There are no strict rules regarding macronutrient ratios or forbidden food groups. People following the CICO diet can structure their diet according to their needs and preferences.

However, there are general nutrition guidelines that may be beneficial for optimizing health and promoting weight loss, such as:

• Macronutrient balance: While the CICO diet does not mandate a macronutrient ratio, a balanced approach can support sustainable weight loss. The Acceptable Macronutrient Distribution Ranges (AMDR), which discuss the recommended percentage of calories that come from carbohydrates, protein, and fat, suggest the average healthy adult consumes:
• Protein: 10-35% of total calories
• Carbohydrates: 45-65% of total calories
• Fat: 20-35% of total calories
• Nutrient-dense foods: Prioritizing fresh, minimally processed foods can help people on the CICO diet stay within their calorie limits while meeting their micronutrient needs.
• Hydration: Staying hydrated is essential to overall health and weight loss.

The CICO diet includes any foods that fit within your daily calorie goals, allowing for a wide variety of options. However, the key is to include nutrient-dense foods that satiate hunger while supporting overall health.

When following the CICO diet, try to prioritize foods like:

• Meat and poultry: Beef, lamb, chicken, pork, duck, and turkey
• Seafood: Salmon, tuna, mackerel, trout, shrimp, and mussels
• Eggs: Whole eggs and egg whites
• Vegetables: Leafy greens, carrots, bell peppers, sweet potatoes, broccoli, asparagus, eggplant, butternut squash, zucchini, and Brussels sprouts
• Fruit: Apples, bananas, oranges, kiwis, grapes, watermelon, canteloupe, honeydew melon, and grapefruit
• Nuts: Almonds, peanuts, cashews, macadamia nuts, walnuts, and pistachios
• Grains: Rice, quinoa, barley, and buckwheat
• Sources of healthy fats: Chia seeds, olive oil, flaxseed oil, and avocado oil
• Dairy products: Milk, yogurt, cheese, kefir, and cottage cheese
• Sweets and desserts: Dark chocolate, baked goods made with whole grains, and frozen yogurt

While the CICO diet is known for its flexibility, limiting or avoiding certain foods can aid weight loss goals and promote overall wellness. Foods that are high in calories and low in nutrients can hinder weight loss and adversely affect overall health.

When following the CICO diet, it may be beneficial to limit your intake of:

• Sugary beverages: Sodas, sweetened teas, and energy drinks
• Fast food: Burgers, fried chicken, and pizzas
• Refined carbohydrates: Sugary cereals, low-fiber baked goods, white flour grain products
• High-fat, low-nutrient foods: Cream-based sauces, sugary desserts, and heavy cream
• Processed snacks: Chips, candy, cookies, ice cream, and deli meats

You can create many nutritionally balanced, CICO-friendly meals that honor your taste preferences and health goals. A day of eating on the CICO diet may look like this:

• Breakfast: Overnight oats with rolled oats, Greek yogurt, chia seeds, and berries
• Lunch: Turkey melt sandwich on whole wheat bread with turkey, Colby jack cheese, spinach, and tomato
• Snack: Carrot stick and hummus; cashews
• Dinner: Baked salmon with asparagus and cooked quinoa

Portion sizes can be tailored to fit your nutritional needs and calorie goals. Be mindful of added calories in condiments, sweeteners, and cooking fats.

The CICO diet and its emphasis on calorie tracking is a straightforward weight-loss approach. With no extensive meal plans or food restrictions, it allows flexibility that may reduce feelings of deprivation. Still, it’s essential to talk with your healthcare provider before restricting your calorie intake for weight loss.

Benefits of the CICO diet may include the following:

• Easy to follow: The CICO diet is simple in its approach. There are no complicated meal plans or food restrictions. Instead, it focuses solely on tracking calories consumed and burned. Its straightforward calculations make the CICO diet easy to understand and implement. Its simplicity encourages consistency over time, which research has linked to significant weight loss.
• Brings awareness to calorie intake: Tracking every calorie can be eye-opening, as it forces you to become more aware of daily habits and portion sizes. It creates a newfound awareness that helps individuals identify high-calorie dishes with little nutritional value and make healthy substitutions as needed.
• Offers flexibility: There are no food restrictions on the CICO diet, only caloric goals. This flexibility may make eating within a calorie deficit easier, as people following the diet can still enjoy their favorite meals and snacks.
• Affordable: Several free calorie-tracking apps are available to support people following the CICO diet, and research has shown that they can benefit sustainable weight loss. These apps typically include a large-scale food database, making it easy for users to log their daily calories and track their nutrient intake. Many platforms also have goal-setting and progress-tracking features to enhance accountability.

While the CICO diet can be a helpful framework for weight loss, it is not appropriate for everyone, and it’s essential to be aware of its potential risks. Not all calories are equal, and restricting dietary intake can have highly adverse effects, such as:

• Inadequate calorie intake: It can be easy to over-restrict calories on the CICO diet, causing your metabolism to adjust to preserve energy. Research has shown that significant calorie deficits can cause metabolic adaptations and a plateau in weight loss. Also, research suggests that energy deficits exceeding 500 calories daily may make it difficult to retain lean muscle mass during weight loss.
• Nutrient deficiency: Focusing solely on calorie intake prioritizes quantity over quality and may lead to dangerous vitamin and mineral deficiencies. Research has shown that calorie-restriction diets can fall short of many recommended nutrient intakes.
• Mental health effects: Successfully following the CICO diet depends on accurate calorie tracking, requiring dieters to log their calorie intake and output strictly. People with a history of eating disorders may find this style of dieting stressful and should consider the potential risks. The obsessive behaviors involved in the calories in, calories out diet may lead to disordered eating patterns and mental health implications.
• Non-nutritive eating habits: The flexibility of the CICO diet may encourage unhealthy eating habits. Consuming high-calorie, low-nutrient foods is possible while remaining within your calorie goal.

Some populations may be especially vulnerable to the risks associated with strict calorie tracking. The CICO diet is not appropriate for children, pregnant and breastfeeding individuals, and people with a history of eating disorders.

Nutrition needs are heightened during pregnancy and lactation, highlighting the need for adequate dietary intake. Similarly, nutrition plays a crucial role in the growth and development of children, and restrictive eating can negatively affect their long-term health.

The CICO diet is highly accessible and doesn’t require a significant financial investment. However, there are a few drawbacks to consider before starting the calorie-tracking diet. One major downside to the diet is the lack of guidance surrounding the restrictions.

Nutritional needs vary between individuals based on their age, sex, physical activity, and medical history. The optimal balance of calories in versus calories out is a guess unless your healthcare provider or registered dietitian (RD) gives you recommendations tailored to your needs.

Also, the CICO diet doesn’t necessarily prioritize nutrient-rich foods, meaning people following the CICO way of eating may stay within their calorie goals without meeting their micronutrient needs. Falling short of these needs can contribute to chronic medical conditions and health concerns.

The CICO “calories in, calories out” diet is established on the principle that creating a negative energy (calorie) balance supports weight loss. It is a straightforward weight management approach that emphasizes tracking calories without restricting certain foods or food groups. It’s relatively easy to follow, and its flexibility allows you to enjoy your favorite foods as long as they fit within your daily calorie goal.

However, the CICO diet is not appropriate for everyone. People following the CICO diet may be at risk for nutrient deficiency and lean muscle loss. Also, obsessively tracking calories may contribute to feelings of anxiousness over food and other mental health concerns.

Prioritizing a well-balanced diet can help mitigate the risks associated with calorie tracking while supporting weight loss efforts.