When we talk about calories, it’s quite common to hear “This has too many calories”, or “Don’t eat that, it’s loaded with calories”. You’ll notice that most calorie chat is around counting them. But is that what it’s really all about? Or is there more to nutrition than just calorie counting?

Let’s try understanding calories first.

What are Calories?

When understanding calories, it’s important to know exactly what “calories” are. We hear them mentioned all the time, but often, the association is negative. Simply put, calorie is a unit of measurement. It’s used to measure the amount of energy we get from foods and beverages. Almost like the watts of a lightbulb.

assorted fruits on brown wooden bowls

Why are calories important?

The amount of calories – or energy – we get from the food and drinks we consume is what our body uses to function and complete activities. And that doesn’t just mean running or physical activity!

By consuming calories, we are able to perform basic functions to sustain a healthy body. Some examples are:

  • Breathing
  • Digesting our food
  • Brain function
  • Regulating body temperature

And then, we also use calories for more complex activities such as:

  • Being more productive at work
  • Physical growth and development
  • Exercise
  • Mood and emotional stability
  • Recovery and healing from injuries, illnesses, etc.
  • and so much more!

How many calories should I eat everyday?

There are a number of factors that you need to consider when working out how many calories you should eat in a day. This depends on things like:

  • Age
  • Sex
  • Height
  • Weight
  • Level of physical activity

Additionally, it’s important to identify your goal in terms of weight management. Are you maintaining your weight? Are you trying to gain or lose weight? And in some cases, health conditions are an important factor too. This is especially relevant for those who are injured, have gone through surgery and are in need of recovery, and those who have serious medical conditions – like diabetes or cancer, for instance.

The 2020-2025 Dietary Guidelines for Americans have detailed explanations of this topic and have a table with an estimated amount of calories you should eat in a day. You can check that out here.

Calorie Deficit vs. Calorie Surplus

Previously, we’ve mentioned that it’s important to identify what your goal is in terms of weight management. This is because we need it to identify if you would be needing a calorie deficit or a calorie surplus.

Calorie Deficit

A calorie deficit is when you consume fewer calories than your required number of calories per day. This is typically done when you are trying to lose weight. Ideally, deficits are only around 500-750 calories per day and this is done gradually. Extreme calorie deficits can be dangerous, and unsustainable.

Tip: To help create a calorie deficit, it’s often a good idea to increase your physical activity. If you’re eating less, and moving more, you’re likely to create a deficit more easily. Together, this can help you gradually lose weight in a healthy and consistent manner. Depending on the type of exercise, this combination can also help improve your body composition by increasing muscle mass.


A 26-year old female who is sedentary (i.e. does no physical activity) would typically need 1,800 calories per day*. And when in calorie deficit, a range from 500-750 calories per day can be deducted from the normal requirement, meaning they’d want to eat around 1200-1300 calories per day.

Instead of making the change suddenly, it’s a good idea to gradually decrease their calorie consumption to avoid drastic changes from their usual routine. This is why seeking guidance from a nutritionist-dietitian is ideal. Their guidance can help you make the change sensible and sustainably.

What you need to know about calorie deficits

Eating too little calories won’t help you lose weight. In fact, consuming too little calories per day can have negative effects to the body in the long run. There are times when people engage in a “very-low-calorie diet” (VLCD), where they consume less than 800 calories a day. Research suggests that this is typically not recommended. These types of diets are only (and very rarely) advised to those who are under strict monitoring under the obesity guidelines.

Calorie Surplus

A calorie surplus is the opposite of a deficit. This is when you consume more calories than your required number of calories per day. Muscle builders, and people who want to gain weight would benefit from calorie surplus. Depending on your health, and goal, a surplus can range from 250-500 calories per day and this is done gradually.

Tip: Together with a calorie surplus, you should usually engage in strength training or resistance exercises to ensure that the additional calories are used to build muscle rather than just adding fat. This approach helps in gaining weight in a healthy and balanced manner.


The same 26-year old female who is sedentary (from the deficit example) would typically need 1,800 calories per day*. When aiming for a calorie surplus, an additional 250-500 calories per day can be added to the normal requirement. This person may gradually increase their calorie consumption to ensure a balanced approach to weight gain.

Seeking guidance from a nutritionist-dietitian helps to ensure additional calories come from nutrient-dense foods. Plus, they can provide a structured plan for healthy weight gain.

What you need to know about calorie surpluses

Consuming too many calories can lead to unwanted fat gain and other health issues. It’s important to monitor your progress and adjust your intake as needed. Eating nutrient-dense foods is crucial to ensure that the extra calories contribute to overall health and well-being, rather than just increasing body fat.

Engaging in a structured exercise regimen, particularly strength training, can help in channeling the extra calories towards muscle growth. This balanced approach ensures that the weight gained is healthy and sustainable.

*Note: The calorie requirement provided in the example was based on the 2020-2025 Dietary Guidelines for Americans

Understanding the Quality of Calories in Food

When understanding calories, it’s also important to evaluate the quality of the food. Counting calories is one thing, but you also want to know what they’re doing for your body. It’s not all about counting calories, and the amount of energy you get from food but it’s also knowing that you’ll be getting the right amount of macronutrients and micronutrients from your calories. While you technically could live on a 1800-calorie diet of takeout and junk food, you likely wouldn’t feel great, and you probably wouldn’t be satisfied or satiated either.

pizza on white ceramic plates

Here’s an overview of what you should know about the quality of calories you get from food:

Low-calorie foods

Low-calorie foods are those that contain relatively few calories per serving, making them ideal for weight management and overall health. These foods are often nutrient-dense, providing essential vitamins and minerals without excessive calories. You can typically eat lots of these to stay full without making too much of a ‘dent’ in your calorie intake.


  • Fruits: Apples, oranges, berries, watermelon
  • Vegetables: Spinach, lettuce, celery, broccoli, cucumbers
  • Lean Proteins: Chicken breast, turkey, fish
  • Dairy and eggs: Plain yogurt, low fat milk, egg

High-calorie foods

High-calorie foods are those that contain a significant amount of calories per serving. While some high-calorie foods can be nutrient-dense, providing essential nutrients along with energy, others may be less beneficial to overall health.


  • Fatty Foods: Fried foods, fatty meats, oils, butter
  • Healthy High-Calorie Foods: Avocados, nuts (such as peanuts), quinoa, olive oil, dark chocolate (in moderation)

Empty calorie foods

Empty calorie foods are those that provide a lot of calories with little to no nutritional value. They are often high in added sugars and unhealthy fats, contributing to weight gain and potential health issues without offering essential nutrients.


  • Sugary Drinks: Sodas, sweetened energy drinks
  • Snacks and Desserts: Cakes, cookies, donuts, muffins
  • Candy: Chocolates, candies, candy bars
  • Processed Meats: Bacon, sausages
  • Condiments and Sauces: Ketchup, mayonnaise
  • Fast Foods and Junk Foods: Pizza, burgers, French fries
  • Solid Fats: Shortening
  • Alcoholic Beverages: Beer, wine, spirits

Check this out

In summary, calories aren’t just about the quantity, but also about the quality! If you’re curious to learn more about calories, you can check out these related blogs we have here at Samsung Food: