The calorie calculator can help you in determining how many calories should you eat a day - and how many to cut if you want to lose weight. In this article, you will find what formulas does our calorie counter use, but also what kinds of food to eat to cut down your weight in a responsible way.
The recommended calorie intake depends on many factors. Some of them are easy to find out: your age, height, weight and sex. Some, like the level of your physical activity, are more qualitative than quantitative, but it's possible to measure and classify them. Other ones, like your metabolism or overall health, are very difficult to estimate. That's why, even though our calorie calculator takes into account most factors that influence the amount of calories you need every day, it may not give results that are 100% accurate. Consider it more of a guideline than a rigorous directive.
For example, a 40-year-old man who has a physical job (equivalent to exercising 5 days a week), is an average American in height (5 ft 9 in) and weight (194.7 lbs) should take in 2764 calories a day. On the other hand, his daughter, an average 16-year-old girl (5 ft 4 in, 117 lbs) who exercises once a week only, needs 1795 calories a day - almost a thousand calories less than her father.
Calories are measures of energy. 1 calorie is equivalent to 4.18 joules.
In nutrition, we actually deal with kilocalories (kcal), where 1 kcal is equal to a thousand of the "smal" calories. As you could expect, 1 kcal = 4.18 kJ. (This article uses the term "calories" to describe kilocalories, like probably every other healthy diet article in Internet).
The calorie calculator bases on the Mifflin - St Jeor equation. It allows you to find your Basal Metabolic Rate (BMR) - the amount of energy needed for your body to support basic vital functions only. It is different for men and women:
BMR(men) = (10 * weight / 1kg + 6.25 * height / 1cm - 5 * age / 1 year + 5) kcal / day
BMR(women) = (10 * weight / 1kg + 6.25 * height / 1cm - 5 * age / 1 year - 161) kcal / day
After you calculate the BMR, you need to multiply it by a factor corresponding to your physical activity level:
If you're not sure which activity level to choose, always go for a lower number. That's because most people overestimate how much they exercise, and if you want to lose weight, it's safer to assume that you are not as active as you'd expect yourself to be.
There are about 3500 calories stored in each pound of body fat (of course, this is an average amount). If you want to lose a pound a week, it is easy to calculate that you need to cut 500 calories from your daily demand. Similarly, if you want to gain weight, taking in additional 500 calories a day will help you gain a pound weekly. Remember that you can create this deficit either by eating less or increasing the demand by exercising.
You should never cut more than 1000 calories a day from your diet. As a rule of thumb, you should never go below 1200 calories a day if you're a woman and 1800 if you're a man.
It's also a good idea to check whether you're really overweight. Our BMI calculator can be of use to you.
Calories are not the only thing we get from food. Eating 1000 calories equivalent of popcorn is definitely not the same as eating 1000 calories from vegetables and fruit. We also need nutrients - food components such as carbohydrates, proteins, vitamins, iron and others. If you want to lose weight, you need to double-check whether you won't deprive your organism of important substances by cutting down your calorie intake.
The best idea is always to consult a specialist, for example a dietitian, who will create a diet plan perfectly suited to your needs. In no case should you blindly follow any diet plan taken from an anonymous source. The list below provides some rules that can become an inspiration for your diet. They are taken from the Dietary Guidelines for Americans. If you are interested in the topic of healthy nutrition, you should give them a look - this document is full of valuable information.