Calories – Carbs, Proteins, and Fats – Why and How Much Do You Need Them?

Updated on April 20th, 2020

The idea of a conscious choice for a healthy life has changed the way people eat, workout, or even go about regular routines. One such prominent change is the dietary habit. Either it is eating organic to build a healthy life or following a particular diet to reduce weight or ward off diseases.

Health experts and people around the globe have realized the importance of it in both short-term and long-term health. The calorie count is one of the most common points that are a vital part of designing any diets.

What Exactly Are Calories?

A calorie is a unit of measurement. It refers to the amount of energy in the diet we intake, including foods and beverages. When we eat the calories in our body increases, it then turns energy, which fuels our body to function effectively. The body uses this energy to perform metabolic processes, regulating body heat, growth of cells or tissues, muscular activity, and various physical and psychological functions.

Everything we eat has calories, but not all of it may be healthy. Because some foods may contain the right amount of calories, but may not be nutritious. Meaning, it doesn’t exhibit any significant benefit to our body.

Example: Carbonated drinks may have calories but have no nutritional value.

Junk foods have high amounts of calories but have minimal nutritional value.

Importance of Understanding Calories

calories importance

Calories are essential, but one should also consider the nutritional value of the food alongside its calories. The calorie need per day also depends on numerous factors, including age, sex, weight, physical activity, and health conditions. It also significantly depends on the basal metabolic rate, which is the energy required to regulate vital functions of the body such as breathing, blood circulation, keeping the body warm, and many others.

Eating excess calories can make one obese and more prone to various chronic conditions. Obesity, diabetes, high blood pressure, liver, kidney, and cardiac disorders are some of the common health issues associated with excess calories.

Besides, lower calorie intake or restricting calories also has various complications associated with it. It can cause nutritional deficiency, hamper metabolism, weaken bones, muscles & immune system, and lower the body’s overall energy. These conditions can severely impact a person’s physical and psychological well-being.

Hence, regulating calorie consumption is highly essential. It not only keeps you healthy but also helps the body in fighting any diseases or infections.

Yes, the calorie count is highly essential. But, the sources of calories and how they impact the body are vital to get the desired results. Be it weight loss or achieving long-term health goals.

calories infographic

How Many Calories Should You Eat in a Day?

As mentioned above, daily calorie consumption depends on various factors, including age, sex, height, weight, and other health conditions. An average adult woman needs around 2,000 calories per day, while an average adult man needs around 2,500 calories per day. It should contain carbohydrates, proteins, and fats, which are the three essential macronutrients. All these three are highly essential for healthy bodily functions.

The calorie intake also depends on the level of physical activity.

Find here the list of the table that gives you a brief idea of daily caloric intake(1).

AGE Sedentary Moderately Active Active AGE Sedentary Moderately Active Active
2 1,000 1,000 1,000 2 1,000 1,000 1,000
3 1,000 1,400 1,400 3 1,000 1,200 1,400
4 1,200 1,400 1,600 4 1,200 1,400 1,400
5 1,200 1,400 1,600 5 1,200 1,400 1,600
6 1,400 1,600 1,800 6 1,200 1,400 1,600
7 1,400 1,600 1,800 7 1,200 1,600 1,800
8 1,400 1,600 2,000 8 1,400 1,600 1,800
9 1,600 1,800 2,000 9 1,400 1,600 1,800
10 1,600 1,800 2,200 10 1,400 1,800 2,000
11 1,800 2,000 2,200 11 1,600 1,800 2,000
12 1,800 2,200 2,400 12 1,600 2,000 2,200
13 2,000 2,200 2,600 13 1,600 2,000 2,200
14 2,000 2,400 2,800 14 1,800 2,000 2,400
15 2,200 2,600 3,000 15 1,800 2,000 2,400
16 2,400 2,800 3,200 16 1,800 2,000 2,400
17 2,400 2,800 3,200 17 1,800 2,000 2,400
18 2,400 2,800 3,200 18 1,800 2,000 2,400
19-20 2,600 2,800 3,000 19-20 2,000 2,200 2,400
21-25 2,400 2,800 3,000 21-25 2,000 2,200 2,400
26-30 2,400 2,600 3,000 26-30 1,800 2,000 2,400
31-35 2,400 2,600 3,000 31-35 1,800 2,000 2,200
36-40 2,400 2,600 2,800 36-40 1,800 2,000 2,200
41-45 2,200 2,600 2,800 41-45 1,800 2,000 2,200
46-50 2,200 2,400 2,800 46-50 1,800 2,000 2,200
51-55 2,200 2,400 2,800 51-55 1,600 1,800 2,200
56-60 2,200 2,400 2,600 56-60 1,600 1,800 2,200
61-65 2,000 2,400 2,600 61-65 1,600 1,800 2,000
66-70 2,000 2,200 2,600 66-70 1,600 1,800 2,000
71-75 2,000 2,200 2,600 71-75 1,600 1,800 2,000
76 and up 2,000 2,200 2,400 76 and up 1,600 1,800 2,000

Consuming the calories, as mentioned above, can help in maintaining proper weight and healthy physical and psychological functions.

When a dietitian or a health expert designs a calorie-diet plan, they also consider muscle-mass, body fat content, bone density, and various other factors, including health and environmental conditions.

Calorie Burn

Everyday our body burns the calories that we consume in the form of foods.

In general, brain metabolism uses around 20% of the energy we get from calories. The rest is used in regulating various body functions, including basal metabolism.

When living in cold environments or lower temperature regions, our body requires more energy from calories to maintain body temperature and to perform other functions. Whilst the warm environment or for people living in a hot temperate region may require lower energy in comparison.

It is not only the calorie content that matters. The type of calories is also highly important for a healthy body. For example, unhealthy fats have higher calorie content, but eating them just to fill the daily calorie need damages the body. Hence, proper regulation of carbohydrates, proteins, and healthy fats are highly essential for both short-term and long-term health.

[Read: 1300 Calorie Diet]

Calories in Food & Their Roles

calories in foods
Image: ShutterStock

There are three primary types of calories in foods, namely carbohydrates, proteins, and fats. Understanding the importance of these calories helps you in sticking to your diets with keen interests.

1. Carbohydrates

Carbohydrates are one of the vital calories and an essential source of energy for the body’s function. They account for nine calories per gram. Based on availability, our body first burns carbohydrates before proteins or fats (2). When we consume carbohydrates, our body breaks it into glucose. The glucose or sugar enters the bloodstream.

The glucose in the bloodstream, also known as blood glucose stimulates the pancreas to secrete insulin. Here, insulin plays a vital role in directing the body to either use the glucose either as energy for the current purpose or to store it for the future. Glucose is an essential source of energy for the brain, red blood cells, central nervous system, and other systems.

For future purposes, the body stores glucose in the liver and muscles. When you are on fast or do not eat for long periods, the pancreas secretes a different hormone that signals the liver to release the reserved glucose.

Carbohydrates Calorie Content

In general, 45 to 60% of daily calories should come from carbohydrates. Excess carbohydrates trigger more insulin, which makes your body store the excess glucose as fat. It can raise blood sugar levels and cause overweight or obesity. Besides, it leads to diabetes, poor metabolic health, fatty liver, and increases the risk of digestive or cardiac disorders (2).

Carbohydrates are also known as carbs.

Carbohydrates are of four types. Namely, simple carbs, complex carbs, fibers and starches.

Candy, sodas, table sugars, and honey are simple carbs that can raise the blood sugar instantly. They are harmful if consumed regularly or in large amounts. These are the common culprits of obesity, diabetes, and heart diseases.

Spinach, broccoli, whole grains, and brown rice are some of the common foods that contain complex carbs. These regulate the blood sugar levels in a healthier way. They also contain essential vitamins and minerals.

Starchy carbs found in potatoes and grains are also a vital source of energy and essential nutrients.

Carbohydrate foods with rich fiber content are known to promote long-term gut health, regulating weight, and also in lowering the risk of heart diseases. Spinach, avocado, and lentils are some of the good sources for it.

[Read: Zero Calorie Foods]

Best Sources for Healthy Carbohydrate Calories

The best way to get good calorie content of carbohydrates is from fruits, vegetables, tubers, nuts & seeds, dairy, and whole grains.

Candies, ice-creams, white bread, preserved foods, sugary or artificially flavored foods, and drinks also contain carbohydrates. But, as mentioned above, these are considered unhealthy, and you may try to avoid it.

2. Proteins

In a regular diet, protein should be around 10 to 35% of the total calorie intake. A gram of protein constitutes nine calories. Similar to carbs, these also help in fueling the body’s energy. Alongside these also play a critical role in the growth and maintenance of the body. Proteins are known as building blocks of life, and even every cell in the body has proteins in it.

Why Are Proteins so Essential?

Proteins are known to have five significant responsibilities in the body. They are a vital building block of bones, cartilage, skin, and muscles. Hemoglobin is a type of protein found in red blood cells that supply oxygen and nutrients throughout the body.

It supports the digestive system, transportation of nutrients, and making new cells and chemicals in the body. One of the key known factors of protein is its role in regulating hormones for growth and development.

Unlike fats or carbs, the body does not store protein, and there is no reservoir to replenish the body when it needs it. Hence, it is highly essential to have the right amount of protein-calorie count in everyday diet. Even most of the hair and nails contain proteins.

There are three main types of proteins and are as follows.

  • The first type of protein is the essential amino acids supplied through food.
  • The second type is the nonessential amino acids made by the essential amino acids or after the breakdown of proteins.
  • The third type is the conditional amino acids required by the body during stress or illness.

Benefits of maintaining proper calorie content of proteins:

  • They enrich the recovery process of the body during physical workouts or injuries.
  • Mitigates the loss of muscles and builds lean muscles.
  • It helps in maintaining and regulating hunger.
  • Curbs hunger and reduces appetite.

Best Sources of Proteins as Calories

Fish or poultry, eggs, tofu, turkey or chicken, lentils or cooked beans, low-fat dairy, and whole grains are a good source of proteins. Nuts and seeds such as almonds, peanuts, peanut butter, walnuts, and sunflower seeds are also a good source of proteins.

Excess or lower calorie content of proteins

Abnormal consumption of proteins can lead to various disorders in the body.

While protein is essential for the body, excess concentrations of protein than the recommended calorie percentage can lead to:

  • Digestive disorders
  • Nausea, or irritability
  • Dehydration
  • Headaches
  • Cardiovascular disorders
  • Kidney or liver issues
  • Osteoporosis or other bone disorders
  • Seizures

At the same time, the lower caloric content of protein can lead to protein deficiency, which can also have various effects on the body. They are as follows:

  • Edema
  • Muscle cramps
  • Weakness
  • Soreness
  • Infections
  • Anemia
  • Brain fog
  • Liver disorders
  • Cardiac problems
  • Malabsorption of nutrients

Is Protein-Diet Good for Weight Loss?

Yes, a protein-rich diet in the recommended dosage can help in weight loss. It does so by reducing food cravings, appetite, promoting weight-regulating hormones, and also by burning more calories.

If you need to maintain a healthy life in the long-run, make sure that your calorie content is well-balanced with all the three essential macronutrients. Lowering or increasing this calorie requirement can hamper health and disrupt the overall functions.

[Read: Keto Friendly Diets]

3. Fats

Fats have a bad image, and in general, some believe that limiting fat is healthy for the body, but that is not true. Like other macronutrient calories, restricting or consuming excess fat can be harmful to health.

Fats like carbs are the essential source of energy for the body, and they should constitute about 25-35% of daily calorie intake. According to a source (4), calories are more energy-dense than carbs or proteins and contain nine calories per gram. They support cell growth, protect organs, regulate the warm temperature in the body, and are also an important part of cell walls. Fats also hydrate and act as an excellent moisturizer for the skin.

Fats are one of the essential calories that play a vital role in hormone and gene regulation. These calories also promote the absorption of fat-soluble A, D, E, and K vitamins.

[Read: Benefits of Okinawa Diet]

Types of Fat in Dietary Calories

There are four types of fats. They are monounsaturated, polyunsaturated, saturated, and trans fats.

Saturated and trans fat are considered bad fats as they are solid at room temperature. These tend to increase bad cholesterol and reduce the good cholesterol levels in the body. Besides, these are the common culprits of obesity, heart diseases, diabetes, inflammation, and other chronic diseases in the body.

Consuming monounsaturated and polyunsaturated fats are essential as they are known to improve heart health, reduce bad cholesterol, and improve good cholesterol levels in the body.

You should restrict the trans fat consumption and try to bring it down to 0% of your daily calorie intake. You can keep the calorie content of saturated fat 10% or lower than that. The caloric content of monounsaturated fat can be around 15 to 20%, while the caloric content of polyunsaturated fat can be around 5 to 10%.

Good Sources of Healthy Fats With Right Caloric Content

  • Walnuts
  • Avocados
  • Whole eggs
  • Chia seeds
  • Extra virgin oil
  • Cheese
  • Sunflower seeds
  • Soybean oil
  • Safflower oil
  • Corn oil
  • Fish such as salmon, herring, mackerel

If you restrict healthy fat or lower the calorie content of it in your diet, it can have the following effects on you:

  • Dry skin
  • Feel more hungry
  • Puts heart at risk
  • Unregulated body temperature
  • Mental exhaustion
  • Chronic inflammation
  • Reduce the padding or support for body organs
  • Probable loss of menstrual cycle
  • Lower absorption of fat-soluble nutrients

Healthy Ways to Regulate or Reduce Calorie Intake


As discussed above, calories in forms of carbs, proteins, and fats are highly essential. Restricting any of them or binging on the other ones can be harmful. However, by careful measure, one can maintain a healthy calorie content by reducing either one of them in a specified and a gradual manner. Below listed are some tips:

1. Drink More Water

Drinking water can increase the number of calories you burn. It does so by increasing the metabolic rate (5).

Other drinks such as green tea, ginger tea, coffee, and other healthy beverages also aid in losing weight and reducing appetite. Besides, these also enrich the body with some vital compounds.

2. Physical Workout

Physical workout can help you increase the calorie burn and also reduce the excess body fat.

Swimming, jogging, skipping rope, push-ups, pull-ups, are some of the best calorie-burning exercises that you can do at home.

3. Minimal Calorie Count

By checking with the dietitian, you can consume minimal calories of carbs and fats, while increasing the amount of protein. A high-protein diet is also one of the most effective ways to lose weight as it increases metabolism, curbs hunger, and appetite.

How Many Calories Does the Body Burn?

The body burns calories in various ways. Not just during physical activity, but even to regulate everyday functions, our body burns calories. The Harris-Benedict formula is one of the most common and widely used techniques to measure calorie burn. It uses the Basal metabolic rate and daily activities. Check the below calculator of the daily calorie burn:

Sex Units Calculation
Metric BMR = 66.5 + ( 13.75 x weight in kg ) + ( 5.003 x height in cm ) – ( 6.755 x age in years )
Imperial BMR = 66 + ( 6.2 x weight in pounds ) + ( 12.7 x height in inches ) — ( 6.76 x age in years )
Metric BMR = 655.1 + (9.563 x weight in kg) + ( 1.850 x height in x age in years)
Imperial BMR = 655.1 + (4.35 x weight in pounds ) + ( 4.7 x height in inches) – (4.7 x age in years )

If you want to get more accurate results, you can also use the below tool:

Harris-Benedict calculator

1. Resting Metabolic Rate

Our body usually burns more calories or uses it in the form of energy for constant functions of building, repairing, and regulating cells and various functions in the body.

The energy needed to perform digestion, respiration, circulation, and the energy needed by the brain to power nerves are some of such regular functions.

2. Daily Routines

Our body also burns calories when we perform our regular activities such as walking even in homes, cleaning, using hands to work, and others. In simple words, any activity or movement that we do requires energy, and it burns calories.

There are various forms of diets such as keto diet, Dubrow diet, Okinawa diet, pescatarian diet, and few others, which help you in reducing one excess calorie intake while enriching the nutritious value.

Bottom line

Calories are the units used to measure energy. If you are planning to go on a diet that involves restricting one or two of the macronutrients, it is highly recommended to consult a dietician or a health expert. Just restricting the calorie intake without understanding the biology and nature of your body can hamper the health condition. It could also have severe negative impacts on both short-term and long-term health.


1. Can We Survive on a Low-Carb Calorie Diet?

Yes, the body can work without high or by reducing the carbohydrate content.

2. Do Men Burn More Calories Than Women?

Yes, men tend to burn more calories than women because of more muscle, heavier bones, and lesser body fat in comparison to women.

View Comments (0)

Leave a Reply

Your email address will not be published.

Scroll To Top

Sign up for our Newsletter !
Get access to quality &
Natural Health Tips right from the Experts
Subscribe !
Send this to a friend