By definition, “a calorie is the energy required to raise the temperature of 1 gram of water by 1 degree Celsius.” The number of calories required to maintain health, may vary from person to person, owing to various factors. But in general, it can be estimated that an adult body requires at least 1000 to 1400 calories to have sufficient energy for the proper functioning of important organs like the brain, heart, and lungs. This minimum number of calories which you need to survive, is known as your resting metabolic rate (RMR). Resting metabolic rate varies greatly, depending upon age, sex, weight and muscle mass. For day to day activities, you need more number of calories than your resting metabolic rate (RMR). This extra energy required can be about 400 to 600 additional calories per day. These numbers are general averages and a dietitian can help you determine exactly how many calories your body needs. You may get an exact answer for your question ‘ how many calories should I eat ‘ after the physical examination of your body. Dietitians usually recommend an increase or decrease of about 500 calories per day according to the need. There are 3500 calories in one pound. Five hundred calories a day amounts to one pound per week. The amount of calories required by a person to be fit and active, may vary according to the basal metabolic rate and the body mass index.

     How Many Calories Should I Eat to Gain Weight
     Each day, if you consume more number of calories than those required by your body, you will eventually gain weight. An excess of 3500 calories is required to gain 1 lb of fat. For example, if your body needs 2000 calories a day to maintain its current weight and every day you consume 2500, in one week you would gain 1 lb. Remember, one day of overindulging does not result in instant weight gain. Read more on weight gain diet chart.

     How Many Calories Should I Eat to Lose Weight
     Obesity is a constant concern today as maximum percentage of the population consumes extra calories, than the amount actually required by the body. If these extra calories are not burnt with proper exercises, they are converted into fats. This leads to increase in weight and other health problems. People who are facing the problem of obesity, are always in search of weight loss diets. As seen above, if you reduce 500 calories from your daily diet, you can lose one pound per week. Both losing and gaining weight is not easy. There are no shortcuts, you should have patience. Consistency in exercising, control over mind while following a balanced diet, lifestyle changes are expected from you. Burning calories without exercising is also possible. Read more on how many calories should I eat to lose weight.

     How Many Calories Should I Eat a Day
     The following information about the daily calorie intake may provide you answer for your question, how many calories should I eat a day. The recommended calories per day for people in the age group between 19-50 years are almost the same. For women belonging to this age group, the recommended calorie intake is about 1,940 calories per day. Of course, this depends upon the age, lifestyle, health and activity level of the woman. The recommended calorie intake for men is about 2,550 calories per day while for children in the age group of 4 to 10 years, it is around 1,500 calories per day.

     The daily calorie intake drastically increases in the age group 11-14, as the body undergoes some changes. The daily calorie intake of boys increases to a gigantic 2,220 calories per day and for the girls it increases to 1,845 calories per day. A similar increase is again observed for the age group of 15-19 where the daily calorie intake for boys is about 2,755 and for girls it is about 2,110.

     If a pregnant woman asks me the question, ‘how many calories should I eat while pregnant ‘, I would tell her that on an average, a pregnant woman needs to increase the amount she eats daily, by about 300 calories. Generally, it is noticed that a pregnant woman gains about 25 to 35 pounds by the time her due date rolls around. Read more on normal calorie intake for females.

     If you ask me the question, ‘how many calories should i eat for breakfast ‘, I would like to tell you that, for breakfast, you should eat about 20-25% of your total day’s caloric intake. Read more on zero calorie foods.

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