The Science & Math of Weight Loss : Learn 5 Basic Rules

Whether you’re interested in losing weight or simply want to learn more about how your body works to shed pounds, it’s important to understand that there are some wonderful science and math equations to lose weight.

While people often make it seem overly complicated, understanding the precise science and math behind weight loss and getting in better shape is much easier than most of us actually think.

1. Calories In and Calories Out

calorie in out

When attempting to lose a pound, the average person would need to burn 3500 calories. Of course, this may seem excessive to those who don’t have enough time or energy for exercising after a long day at work.

However, most don’t realize that your body burns quite a few calories on its own, even when you’re sitting down and relaxing.


For example, an average individual burns roughly 50 calories per hour as they sleep, meaning sleeping for eight hours equals around 400 calories burned.

Calories burned by our body for its basic functioning is called ‘Basal Metabolic Rate” or BMR. You can check your BMR using the free calculator below.

BMR & Calorie Calculator

require require

Your body Carb requirment ......

The calorie count is then adjusted based on your goal:

  • Weight loss: Reduce by 10-20%
  • Weight gain: Add 500 calories
  • Weight maintenance: Unchanged
  • This calorie count is split into macronutrient percentages in the following ratios, based on splits commonly recommended by our nutrition experts for muscle gain, weight loss, and weight maintenance. (Yes, weight gain and maintenance are the same ratio, but the calories and macros are different.)

    • Weight loss: 40/40/20 (carbohydrates/protein/fats)
    • Weight gain: 40/30/30
    • Weight maintenance: 40/30/30
    • Finally, your carbohydrate intake comes from applying those percentages to your daily calorie number. Each gram of carbohydrates is "worth" 4 calories.

If the calculator has shown your BMR in 1500-2000 range (depends on your age, gender, and activity level) it means that your body burns so many calories even when you are doing almost nothing. Fantastic right!

How Does it Happen?

In addition to burning calories when you sleep, you can burn them while doing random things, such as sitting and reading a book or preparing a meal in the kitchen. And you will burn even more calories when walking and participating in physical activities, such as jogging, pilates, heavy lifting, and more.

As burning 3500 calories can help you shed a pound, you should consider a calorie deficit to help you reach your weight goal.

If you’d generally consume around 2000 calories to maintain your current weight, a reduction of roughly 500 calories per day can help you lose around one kg of weight a week, while maintaining or increasing activity levels to see that number drop on the scale.

Now let’s conclude the math.

If you can reduce 500 calories per day by eating a little less (perfectly doable) you are going to burn 1 pound fat in a week’s time. However, when you are on a mission to burn fat, you should aim to burn 500 more calories by doing some physical activity.

So, overall, you are causing 1000 calories deficit per day, 30,000 calories per month. That’s about 8.5 lbs of fat gone in a month with little effort. WOW!

That’s about weight loss math. Now let’s investigate some scientific facts.

2. Are All Calories Equal?

All calories are not equal

All calories are not equal. Here’s What you need to know

Not all calories are equal. Dieters must know this fact when dieting and attempting to reach a goal weight.

In fact, certain foods can leave you feeling full, keeping you off from snacking between some of your main meals and helping you on a weight loss journey.

However, some foods may have the opposite effect, making you feel even hungrier.

Unfortunately, an excessive amount of carbohydrates, such as bread, pasta, and sweets, can cause the body to begin storing fat instead of using it for energy. When the body stores fat, it often leads to weight gain instead of weight loss.

Therefore, your diet should consist more of foods that can make you feel fuller for longer. These are nothing but protein rich foods. They also help you lose fat faster if you add exercising to your routine. Use the calculator below to find out your daily protein need.

Protein Calc

age should be in 14 to 80 range
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You should take ...... of protein per day

With this in mind, even if a bag of chips or a brownie is anywhere between 100-300 calories, you’re still better off eating something with same amount of calories but good for you, such as a fresh fruit salad or baked seasoned vegetables. Healthy foods tend to boost metabolism, helping your body burn off excess fat faster so that you can shed unwanted weight.

3. Know about Low Glycemic Index (GI)


When trying to reach a healthy weight, it is good to follow a low-glycemic index diet which consists of foods, that help stabilize blood sugar, such as broccoli, cabbage, eggplant, spinach, and peppers.

Not only are these foods good for the body, but they also help prevent health issues like heart diseases.

When you are on ‘mission weight loss mode’ avoid over sugary fruits like Mango, Sapodilla (Sapota), cherries etc. Replace them with Avocado, Guava, Papaya etc.

See complete list Glycemic Index chart for more ideas.

Check our free Glycemic index chart here.

4. How Does Exercise Supplement Your Diet?

how exercise aid weight loss

Although a healthy diet consisting of more fresh fruits, vegetables, and whole grains can help you with your weight loss journey, exercises also supplement the diet and help you cross the hurdles rather in an easy way.

Any healthy weight loss plan must include a exercise plan.

When you’re moving your body and getting active,

  • you’re building muscle,
  • gaining strength,
  • and burning calories, making it easier to shed pounds at a steady pace.

Visit our Workouts section for easy exercise ideas.

Losing weight may seem complicated, but it’s a matter of understanding how many calories to consume, which foods are best to eat and how to incorporate more physical activity into our routine to burn additional calories. With the right approach, you can reach your goal weight in time.

This is an elementary level information about losing weight the right way everyone should know. However, we want to add one more additional point about metabolism

5. Understand the metabolic process

Metabolism is all about how many calories you burn daily, and the much discussed “slow and fast metabolism” is more of a myth than reality.

Well, it is a fact that metabolism and weight go hand in hand but contrary to the idea, slow metabolism is not the reason for increased weight, at least not directly. It’s the food intake and the amount physical exercise and activity that determine your weight gain or weight loss.

Metabolism and Weight Loss-Are They Related?

Metabolism and Weight Loss-Are They Related?

There are many ,similar questions which sprout in the mind of health or rather “weight” conscious people, who often curse the slow metabolism rate for their weight gain, but is it really so?

If you intake more food than your body is able to burn into energy, then the excess amount is stored in your body, mostly in the form of fat.

This excess amount also influences the hormonal activity responsible for metabolism and hence hinders the metabolic rate.

To overcome it or control it, you have to engage yourself in some physical activities like exercises, sports, swimming, biking etc. which would help in burning the excess calories and also develop lean body muscles and reduce the fat percentage in your body resulting in weight loss.

The so called “modern dieting” is a similar diet plan where the body consumes less than what it burns. In fact, all those metabolism boosting diet programs, meal replacement plans, pills, potions and supplements would only assist you to consume fewer calories because ultimately it’s all about ‘calories-in & calories-out’.

Accelerated fat burning, turbocharged metabolism, 5 seconds iced water hack etc. are merely marketing words to fool ignorant people!

Read this >> More about metabolic process ‘catabolism & anabolism

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