Speaker 1: Welcome to brain Stuff from how stuff works dot com
Speaker 1: where smart Happens. I am Marshall Brain with today's question,
Speaker 1: how many calories does a person need daily? The number
Speaker 1: of calories the body consumes in a day is different
Speaker 1: for every person. You may notice on the nutritional labels
Speaker 1: of the foods you buy that the percent daily values
Speaker 1: are based on a two thousand calorie diet. Two thousand
Speaker 1: calories is a rough average of what a person might
Speaker 1: eat in a day, but your particular body might need
Speaker 1: more or less than two thousand calories. Height, weight, gender, age,
Speaker 1: muscle mass, and activity level all affect your caloric needs.
Speaker 1: There are three main factors involved in calculating how many
Speaker 1: calories your body needs in a day. First, there's your
Speaker 1: base al metabolic rate. Second there's your physical activity, and
Speaker 1: third there's the thermic value of food. Your basil metabolic rate,
Speaker 1: or BMR, is the amount of energy your body needs
Speaker 1: to function at rest. This accounts for about sixty two
Speaker 1: seventy of the calories burned in a day, and it
Speaker 1: includes the energy required to keep the heart beating, the
Speaker 1: lungs breathing, the eyelids blinking, the body temperature stabilize the brain, thinking,
Speaker 1: and so on. In general, men have a higher BMR
Speaker 1: than women do. One of the most accurate methods of
Speaker 1: estimating your basil metabolic rate is the Harrass Benedict formula.
Speaker 1: For example, for an adult male, you take sixty six
Speaker 1: plus your body weight and pounds times six point three
Speaker 1: plus your height niches times twelve point nine minus your
Speaker 1: age in years time six point eight, and that will
Speaker 1: give you your basel metabolic rate. The second factor in
Speaker 1: the equation, physical activity, consumes the next highest number of calories.
Speaker 1: Physical activity includes everything for making your bed in the
Speaker 1: morning to jogging, walking, lifting, bending, and just generally moving
Speaker 1: around burns calories. But the number of calories you burn
Speaker 1: in any given activity depends on your body weight. There
Speaker 1: are many sites on the web that will help you
Speaker 1: to calculate the number of calories that you use in
Speaker 1: different activities. Finally, the thermic effect of food is the
Speaker 1: final addition to the number of calories your body burns.
Speaker 1: This is the amount of energy your body uses to
Speaker 1: digest the food you eat. It takes energy to break
Speaker 1: food down to its basic elements in order to be
Speaker 1: used by your body. To calculate the number of calories
Speaker 1: you expend in this process, multiply the total number of
Speaker 1: calories you eat in a day by point one or
Speaker 1: ten percent. If you need some how determining how many
Speaker 1: calories you eat in a day, look for a free
Speaker 1: food diary site on the web. The total number of
Speaker 1: calories of body needs in a day is the sum
Speaker 1: of these three different calculations. Do you have any ideas
Speaker 1: or suggestions for this podcast? If so, please send me
Speaker 1: an email at podcast at how stuff works dot com.
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