whTfvSqbnY - Calories and Caloric Needs Six Major Nutrients...

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Calories and Caloric Needs Six Major Nutrients in Food - A nutrient is any subst ance in food that the body can us e to obt ain e n ergy, synthesize tissues, or regulat e functions - Essential Nutrients fall into 6 cat egories: o wat er, carbs, lipids (fats and oils), proteins, vita mins, a nd minerals - A deficiency is the sign of a lack of a nutrient in the diet (ie: scurvy, a n e mia, Functions of Dietary Nutrients - 3 major functions o Contribute to cell and body structure o Provide energy o Regulate body processes - Macronutrients : ne ed ed in large quantities (carbs, protein, fat) - Micronutrients : n e ed ed in s m all a m ounts (vita mins, minerals) Key Differences Among Nutrients - Cell and body structure lipids, protein, water, minerals - Provide energy carbs, lipids, protein - Regulate body processes lipids, proteins, water, vitamins, minerals Nutrients: Organic or Inorganic - Organic: substa nce s tha t conta in ca rbon o Ca rbs, lipids, prote ins, vita m ins - Inorganic : substa nce s tha t do not conta in ca rbon o Mine ra ls, wa te r Ene rgy in Foods - Food contains chemical energy in the form of kilocalories . - 1 kcal = the amount of energy needed to raise the temp of a kilogram of - 1 food calorie = 1 kilocalorie = 1,000 calories Measuring Food Energy - Food energy is measured using a bomb calorimeter - Food energy values o Carbs = 4 cal/gram o Proteins = 4 cal/gram o Lipids = 9 cal/gram o Alcohol = 7 cal/gram Calculating Calories in Food - Amount of component x cal/gram = calories - Example: How many calories are in a Big Mac with 45 grams of carbs, 25 grams of protein, and 29 grams of fat? o 45 grams of carbs x 4 cal/gram = 180 calories o 25 grams of protein x 4 cal/gram = 100 calories o 29 grams of fat x 9 cal/gram = 261 calories o Total = 541 calories
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Be Food Smart: % Calories in Food - Recommendation: 30% or less of your total calories from fat each day - Example: You and your date share a bucket of hot buttered popcorn at the movies. Your share of calories is 825 and 38 grams of fat. Does this splurge o 38 grams x 9 cal/gram = 342 calories from fat o 342 calories from fat / 825 total calories = 41% Energy Release from Food - The gastrointestinal (GI) tract is the body’s organ which digests food and - Digestion = chemical and physical breakdown of food into smaller units - Absorption = movement of digested nutrients from GI tract into the Functions of the GI Tract - Ingestion: receipt and softening of food in the mouth - Transport of ingested food - Secretion of digestive enzymes, acid, mucus, and bile - Absorption of the end products of digestion - Movement of undigested material - Elimination of digestive waste products Parts of the GI Tract - Mouth - Esophagus - Stomach - Small Intestine - Large Intestine - Rectum Special Features of the GI Tract - Long hollow tube (central space is the lumen) - Lined with mucosa cells (screening, absorption) - Muscles control movement (circular, longitudinal, and sphincter) - Peristalsis moves and mixes (rhythmic contractions)
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whTfvSqbnY - Calories and Caloric Needs Six Major Nutrients...

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