“the science of food, the nutrients and the substances, their action, interaction, and balance in relation to health and disease, and the process by which the organism ingests, absorbs, transport, utilizes, and excretes food substances”----The Council on Food and Nutrition of the American Medical Association

The social, cultural, psychological implications of food and eating

Provide energyProvide building blocksVital for growth and maintenance

Essential

Omission leads to declineRegain normal function when restored to the diet

Has specific biological function

Poor diet and sedentary lifestyle Risk factors for chronic diseases Poor diet and sedentary lifestyle are risk

factors for chronic diseases:◦ Disease of the heart (26.6% of all deaths)◦ Cancer (22.8%)◦ Cerebrovascular disease (5.9%)◦ Diabetes (3.1%)◦ Accounts for ~2/3 of all deaths

“Affliction of affluence” Optimal health We are living longer Your choice

Carbohydrates Fats Proteins Vitamins Minerals Water

Kcals-measure energy Essential nutrients Nonessential nutrients Energy-yielding nutrients: CHOs, P, fats Nutrients for growth, development, and

maintenance Nutrients that regulate body processes

Composed of C, H, O Provide a major source of fuel for the body Basic unit is monosaccharide (glucose) Simple and Complex CHO Energy yielding (4 kcal /gm)

Composed of C, H and fewer O Triglyceride is the major form of lipid Fats and oils Unsaturated Fatty Acids Saturated Fatty Acids Essential Fatty Acids (Omega 3, 6) Energy yielding (9 kcal /gm) Cholesterol and phospholipids

Composed of C, O, H, N Basic unit is amino acid Make up bones, muscles, other tissues, and

components (9) Essential amino acid (11) Nonessential amino acid Energy yielding (4 kcal /gm)

Composed of various elements Vital to life Enable chemical reactions Needed in tiny amounts Fat soluble Water soluble-destroyed in cooking Yields no energy

Inorganic substances-lacking carbon Function in cellular process, nervous

system, water balance, structural Needed in tiny amounts Not destroyed in cooking Trace minerals Major minerals Yields no energy

Composed of H, O Vital to life-forgotten nutrient Is a solvent, lubricant, medium for

transport, chemical processes, and temperature regulator

9-13 cups/day Makes up majority of our body 60% Yields no energy, no calories Inorganic

A chemical found in plants

◦ Not considered essential nutrients◦ Provide significant health benefits◦ Primarily found in fruits and vegetables

Carbohydrate Protein Fat Alcohol

4 kcal/gm 4 kcal/gm 9 kcal/gm 7 kcal/gm

ENERGY SOURCES

Build new compounds Muscular movement

Nerve transmission Ion balance

Measurement of energy“The amount of heat it takes to raise the temperature of 1 gram of water by 1 degree Celsius”

1,000 calories = 1 kcal = 1(food) Calorie

CHO: 4 kcal/gm Protein: 4 kcal/gm Fat: 9 kcal/gm (Alcohol: 7 kcal/gm) NOT A NUTRIENT!

Per serving FIG. 1.3 , pg. 12◦ CHO: 15g x 4 kcal/g = 60 kcal◦ PRO: 3g x 4 kcal/g = 12 kcal◦ FAT: 1g x 9 kcal/g = 9 kcal◦ TOTAL: 81 kcal, rounded down to 80

One day’s intake (1980 kcal) 290 gm of CHO (x 4 kcal/gm) 60 gm of fat (x 9 kcal/gm) 70 gm of protein (x 4 kcal/gm) % of kcal as CHO= (290 x 4)/1980 = 0.59 or

59% % of kcal as Fat= (60 x 9)/1980 = 0.27 or

27% % of kcal as PRO= (70 x 4)/1980 = 0.14 or

14%

16% of kcal as proteins◦~66% from animal sources◦10-35% advised

50% of kcal as carbohydrate◦~50% from simple sugars◦45-65% advised

33% of kcal as fat◦~60 % from animal fats◦20-35% advised

National Health and Nutrition Examination Survey (NHANES) [US Dept. of Health & Human Services]

Monitor energy intake Salt (sodium) in moderation Alcohol in moderation Fat in moderation Adequate fluids Eat 5-A-Day; DASH 8-A-Day Use supplements wisely, if at all Mealtime is a social time

Promote healthy lifestyle Reduce preventable deaths and diseases Reduce obesity in adults and children Increase intake of fruits, vegetables, and

whole grain products Lower intake of fat, saturated fats, and

sodium Increase intake of calcium and iron

Hunger◦ Physical biological drive

Appetite◦ Psychological drive

Hypothalamus◦ Neuropeptide YStimulates appetiteCauses CHOs cravingsDecreases energy

expenditureGhrelin-stomach cells-triggers appetite-lean people made more

Leptin-suppresses appetite-increases satiety-decreases fat depositionInsulin also increases

appetite CCK (cholecystokinin)Contributes to satiationPerson feels full ses fat

storage Serotonin increases satiety

Copyright 2005 Wadsworth Group, a division of Thomson LearningCopyright 2005 Wadsworth Group, a division of Thomson Learning

Hunger-physiological need to eat; unpleasant sensation;originated by chemicals in the brain.Influenced by: presence/absence of food, size & composition of a meal, eating patterns, climate, exerciseStomach designed to eat every 3-4 hours; as it empties the physiological signs start

Appetite-psychological desire to eat, pleasantA positive sensation to seek food involving the senses of smell and sight

Satiation-feeling of satisfaction that occurs during a meal and halts eating; receptors in the stomach stretchremind us to stop eating

Satiety-feeling of satisfaction or fullness. remind us not to eat again

People can override the signals!

Copyright 2005 Wadsworth Group, a division of Thomson LearningCopyright 2005 Wadsworth Group, a division of Thomson Learning

After fatty foods pass your lips and before they settle on to your hips, they go to your brain. And that may be an important clue to why - and when - we're prone to overeat. Research from the University of Texas Southwestern Medical Center in Dallas suggests that when certain molecules of saturated fat reach the brain, they interrupt signals (from the hormones leptin and insulin) that normally suppress appetite after we've eaten. The culprit most responsible is palmitic acid, a saturated fat found in foods such as butter, cheese, milk and beef. Absent this signal from the brain that we've had enough, we keep eating. The signaling disruption lasts about three days, the investigators said. They looked at the effects of fat on animals' brains by feeding them palmitic acid, monounsaturated fatty acid and oleic acid, an unsaturated fat found in olive and grapeseed oils. The only fat that sabotaged leptin and insulin signals was palmitic. The study was published in the September 2009 issue of The Journal of Clinical Investigation. Other new research showed that we tend to eat less when with a heavy friend who eats large portions and more when we're with a thin friend who eats a lot, suggesting social signals also influence patterns of eating. That study was published online on August 25, 2009 in the Journal of Consumer Research.

Regulated by the hypothalamus

Feeding center Satiety center Meal size and

composition Macronutrients in the

blood Hormones

Freshman Fifteen◦ Stressful situations◦ University environment◦ Peer pressure◦ Alcohol◦ Lack of Exercise

Tips to avoid the freshmen fifteen◦ Eat breakfast◦ Plan ahead◦ Limit liquid calories◦ Stock the fridge with healthy choices◦ Exercise regularly