Teach Me

Reduced-Calorie Diet: Pros, Cons and a Basic Guide

Many people start a new diet because they’re struggling with their unhealthy eating habits. If you’re looking to make changes to your diet and improve your physical wellness, such as losing weight, you may have considered cutting back on how much you eat with a reduced-calorie diet.

A reduced-calorie diet is an eating plan that involves limiting the overall number of calories you eat or drink in a day. Limiting what you eat and drink can have some benefits, but it can also negatively impact your health in many ways.

Before you swap your Twinkies and Diet Coke for celery and water, here’s what to know about a reduced-calorie diet so you can stay on track with your wellness goals.

Reduced-calorie diets should be done short-term

The 2020–2025 Dietary Guidelines for Americans suggest a diet of 1,600 to 2,400 calories per day for most adult females and 2,200 to 3,000 for males to maintain your weight.

However, a reduced-calorie diet focuses on the extreme limitation of food and calories. By taking in less calories than you burn (through exercise and daily living), you’ll start to lose weight.

A reduced-calorie diet can contain as low as 800 calories a day but, on average it’s around 1,200 to 1,500 calories a day, which tends to be unsustainable.

“Some study results suggest that calorie restriction may have health benefits for humans, but more research is needed before we understand its long-term effects,” said Beril Hezer, a registered dietitian with Banner Health. “There is no data in humans on the relationship between calorie restriction and longevity.”

“This type of diet should be done under the surveillance of a registered dietitian to avoid overly restricting calories or missing out on essential nutrients,” said Hezer.

When focusing on weight loss, it can be beneficial to focus on long-term results with little changes each day that will add up to weight loss in the future.

You may experience other effects than just weight loss

You may start to look more svelte, but you could experience negative side effects as well. If you’re a little overzealous about calorie counting and reduce your calories too low, you could risk missing out on important nutrients, such as calcium and iron. This can leave you feeling tired and sluggish.

Feeling hangry or foggy headed? When you aren’t eating as much, you could also feel more mentally and physically exhausted.

Seek help from a health care professional

While a reduced-calorie diet may intuitively be as simple as cutting back on your food intake, calories must be counted. You’ll need to know how much food you eat and drink at every meal to count calories. You may even need to use measuring tools, such as a food scale, food journal or an app, to try to keep your calorie counts precise.

Another thing you can do is seek help from a health care provider, such as a registered dietitian who has experience in weight management. They can evaluate your overall health to determine if a reduced-calorie diet is right for you and then plan out the perfect diet based on your medical history and data.

Reduced-calorie diets aren’t for everyone

If you’re looking to lose a quick couple of pounds, this form of extreme diet isn’t right for you. In addition, reduced-calorie diets aren’t recommended for athletes and those who have an eating disorder, are pregnant or breastfeeding or are under age 18. Dieting can also have emotional and psychological consequences.

“Reduced-calorie diets are typically recommended for obese patients for the sake of their health but there are numerous factors that play into obesity such as hormonal disturbances, interactions with the gut microbiome, lack of sleep and socioeconomic status,” Hezer said.

What can I eat and drink on a reduced-calorie diet?

There is no official rule on what you can and cannot eat on a reduced-calorie diet. If you’re eating mostly reduced-calorie junk food and diet soft drinks, you may lose weight, but it could be at the expense of your health. 

“Choose fresh whole foods that are naturally low in calories if weight loss is the goal, such as vegetables,” Hezer said. “Things that are low in calories but also filling are oats, Greek yogurt, soup, berries, eggs, popcorn, cottage cheese, legumes and watermelon.”

Focus on foods that provide more calories per bite, such as those packed with nutrients and fiber. Another sustainable way to maintain a healthy body weight is to swap food items.

“Instead of whole yogurt, try low-fat Greek yogurt. Instead of fruit-flavored yogurt, try plain yogurt and fruit or pick ones with less added sugar. Instead of whole milk, try low-fat milk or almond milk,” Hezer said. “Additionally, swapping foods that require more chewing, such as adding raw vegetables and salads into your meals, is recommended because it takes 20 minutes for your brain to send signals that you’re full.”

Here are some foods you can eat on a reduced-calorie diet:

  • Dairy products and alternatives: Low-fat milks, yogurts and cheese and dairy alternatives like soy, almond, cashew, coconut and hemp
  • Fruit and vegetables: All fresh and frozen fruits and vegetables
  • Whole grains: Whole wheat breads and pastas, brown rice, barley and quinoa
  • Meats and meat substitutes: Lean meats, such as chicken and fish, eggs, tofu, nuts and seeds
  • Fats: Olive oil, nut or seed oils and avocados
  • Drinks: Water, sparkling water, coffee and tea

What to avoid: Refined carbohydrates (like chips and cookies), high-fat foods and sweetened beverages (like Coke and other sodas)

Try out these reduced-calorie recipes including breakfast, lunch and dinner from EatingWell:


Eating and drinking fewer calories than you burn can help you lose weight, but it may not be simple or suitable for you. Speak to your health care provider or a registered dietitian before going on this or any other kind of diet. To find a doctor or registered dietitian at Banner Health, visit bannerhealth.com. With their expertise, you’ll find out the best course of action for you, including creating a diet plan, monitoring your progress and adjusting your diet as needed.

Related articles:

Decoding the Diet Nutrition Weight Loss