NUTR 3210 Lecture 3: Unit 3

• School: University of Guelph
• Department: Nutrition
• Course: NUTR 3210
• Professor: Genevieve Newton

Document Summary

Energy metabolism: sum of all chemical reactions involved in obtaining and utilizing food energy. Energy: capacity to do metabolic/physical work in cells, atp is predominant source of energy; cellular atp comes from dietary macronutrient intake: measured by calories/calories. When foods consumed and macronutrients are broken down into useable units, they serve functions but eventually be oxidized to co2 and produce energy for bodily functions. Energy stored in chemical bonds of fats, carbs and proteins can be released as heat. Energy balance = energy in energy out. Difference between energy intake and energy expenditure. Changes in total body e(cid:374)e(cid:396)g(cid:455) does(cid:374)(cid:859)t (cid:373)ea(cid:374) total (cid:271)ody weight will change. Positive energy balance: when dietary energy < energy expenditure; (from food and drink) i. e. infant/childhood growth, pregnancy, exercise- induced lean mass; over nutrition. Negative energy balance: when dietary energy > energy expenditure (from metabolic & over nutrition i. e. protein/calorie malnutrition (pcm), exercise induced- loss in adipose; infection/fever; age muscle loss (sarcopenia)