Diploma in Hospitality Management
Nutrition
Lecture Two
Refer to page 29 of Food Nutation text
This lecture will discuss four the energy supplied in nutrients and how much you need.
Bomb calorimeter measures the energy released when the food is burnt.
This includes energy from indigestible foods as well as digestible food .The energy content of this "fibre" must be subtracted from the bomb calorimeter measurement.
Carbohydrate contain 16 kj/gram
Protein contain 17 kj/gram
Fat contains 37 kj/gram
Alcohol contains 29 kj/gram
Vitamins and Minerals are need to effectively extract energy from the macronutrients
The extraction of energy from food
Repackaging energy in ATP packets
Glucose = approx 100 ATP
But catabolism yield up 38 ATP / glucose
and as little as 0 ATP as in Brown Adipose Tissue
The rest is lost as heat
The average day can be dived into three stages: Rest Work and Play
Energy need for each stage are about: 2000kj 3-4000kj 3-4000kj
Over all per day = from 6000kj for total bed rest to 10,000 for a very active individual
The need depend on body mass and sex
How can the energy needs of the body be measured
?The energy released by catabolism can be measured indirectly by measuring the amount of CO2 breathed out This is called "Indirect Calorimetry".
People can have a respirometer attached so that oxygen in and CO2 breathed out can be measured or people can be housed in a room connected to monitors that measure the O2 going into the room and the CO2 going out.
Which nutrients are used first for energy?
Actually all macronutrients are used for energy all the time. Different material in different tissues eg.:
The brain needs glucose
Aerobic Muscles use fat
The liver uses mainly excess protein.
chance of early death
chance of early death
Obese people do not get osteoporosis. This may be due to their higher insulin secretion reducing calcium lost in the urine.
Obesity caused by physiology
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