Energy

1. Energy • Capacity to do work • Derived from the sun • Photosynthesis—co2 + h20 • Humans consume plants and animal flesh • **Carbohydrate,*fat, some alcohol intake, minimal amount of protein • Body uses energy • ATP (water is a byproduct) • Body weight is an indicator (of adequacy and inadequacy)

2. Components of Total Energy Expenditure • Basal metabolic rate • Amount of energy expended at rest in a neutral temperature (if too hot/cold may get inaccurate reading) • Thermic effect of food (TEF) • The cost of processing food • Fat has lowest thermic effect (b/c easiest to digest) • Protein has highest thermic effect (b/c difficult to digest) • Activity thermogenesis • Production of heat energy (from activity) • Most variable!

3. Basal and Resting Energy Expenditure • Minimal energy compatible with life • Breathing, sleeping • Energy used over 24 hours • 60% to 70% of total energy expenditure (TEE)

4. Factors Affecting REE • Body size (obese individuals: uses more energy b/c body has increased need to support large body) • Body composition (lean vs. high fat muscle mass) • Age (basal metabolic rate decreases 2-3% every decade after 30) • Sex (men who have lean body mass have higher rate) • Hormonal Status (females: post-menopausal, calorie needs go down) • Caffeine, nicotine, and alcohol (caffeine/nicotine speed up basal metabolic rate—if decreases, true increase in weight; alcohol—slows down basal metabolic rate—if decreases, caloric intake decreases as well) • Fever (increased temp can increase caloric intake 10-15%) • Extreme environmental temperatures (may alter caloric needs as well)

5. Thermic Effect of Food • Accounts for about 10% of TEE • Protein—higher than fat • Obligatory and facultative thermogenesis • Affected by composition of the diet • Spices can increase TEF • Schedule can alter TEF (if divide meals up throughout day, the body will utilize nutrients more efficiently throughout the day versus if you eat all your food at night)

6. Activity Thermogenesis • Energy expended during sports or fitness exercise and activities of daily living • **Most variable component of TEE (altered the most) • Affected by body size, efficiency of individual habits of motion, fitness level • Fine tuned athlete may have a factor of 1.5-2 • Couch potato may have factor of <1-1

7. Units of Energy Measurement • Kilocalories (kcal) Carbohydrate = 4 kcal/g Protein = 4 kcal/g Fat = 9 kcal/g • Kilojoule (kJ) – the metric value Carbohydrate = 17 kJ Protein = 17kJ Fat = 38 kJ

8. Measuring Energy Expenditure • Direct calorimetry • Measures the heat of chemical reaction • Used mostly in research/laboratori • Accurate reading • **Indirect calorimetry gold standard0 • Calculating heat in a living organism that’s produced from production of carbon dioxide and nitrogen waste • Used more commonly—esp. in hospital • Accurate reading • Doubly labeled water • Tracking hydrogen & oxygen that has been partially replaced in body using isotopes—measures CO2 production

9. Estimated Energy Requirements • Each method for calculating energy needs differs and has limitations (b/c is a formula) • Good starting point • Cereal measurements & recall—take into account

10. Measuring energy Intakes • Self-recorded estimates • Ex: Fitday • Limitations: accuracy • Self-reported estimates • Ex: 24-hr recall • Limitations: accuracy (not reporting all they ate; females tend to underreport) • Underestimating and underreporting

11. Estimation of Energy Expenditure • Harris-Benedict equations (oldest formula) Women – REE (kcal) = 655+9.56 xwt(kg) + 1.85 xwt(cm) 4.68x(age) • Men – REE ( kcal) = 66.5+13.75 x wt (kg) + 5 x ht.(cm)-6.78x(age)

12. Estimation of Energy Expenditure • **Mifflin-St Jeor (gold standard—came in the 90s) • Men: RMR = 9.99W + 6.25 H – 4.92A+5 • Women: RMR = 9.99W + 6.25H-4.92A-161 • W=weight in Kilograms • H=height in centimeters • A=Age in years

13. Total Energy Expenditure • Multiply the REE by a physical activity level (PAL) • Chair-bound PAL 1.2 • Seated work PAL 1.4-1.5 • Standing work PAL 1.8-1.9 • Significant activity (30-60 min. 5 x wk) + 0.3 • Strenuous work PAL 2-2.4

14. Vitamins and Metabolism • Vitamins and minerals • Are required for proper metabolism • Do not directly provide energy • *Function as coenzymes • Are necessary for obtaining energy from the macronutrients

15. Vitamins and Metabolism • Enzymes: a protein that accelerates the rate of a chemical reaction. • Required for all metabolic reactions • Coenzymes: a molecule that combines with an enzyme to facilitate enzyme function. • Vitamins and minerals! • Only required for some metabolic reactions

16. Vitamins and Metabolism

17. Vitamins and Metabolism

18. Thiamine Coenzymes • Thiamine Monophosphate (TMP) • Thiamine Triphosphate (TTP) • Thiamine Pyrophosphate (TPP)

19. Riboflavin Coenzymes • Flavin Adenine Dinucleotide (FAD) • Flavin Mono Nucleotide (FMN)

20. Niacin Coenzyme • Nicotinamide Adenine Dinucleotide (NAD) • Nicotinamide Adenine Dinucleotide Phosphate

21. Vitamin B6 Coenzyme • Pyrodridoxal Phosphate (PLP)

22. Folate Coenzyme • Tetrahydrofolic acid (THF)

23. B-complex Vitamins • The B-complex vitamins are especially important for energy metabolism. • The B-complex vitamins include: • thiamin (B1) folate • riboflavin (B2) vitamin B12 • niacin pantothenic acid • vitamin B6 biotin

24. B-complex Vitamins • Thiamin (vitamin B1) • Coenzyme thiamin pyrophosphate required for carbohydrate metabolism • Best source= whole grains (enriched sources) • Beriberi – deficiency of thiamin resulting in muscle wasting and nerve damage

25. B-complex Vitamins • Riboflavin (vitamin B2) • Is part of coenzymes involved in oxidation-reduction reactions • Apart of the antioxidant enzyme—assists with fighting against oxidative damage (cancers, disease states) • Milk is a good source of riboflavin (light sensitive container) • Meats • Fish • Ariboflavinosis – riboflavin deficiency; sore throat, fatigue, swollen mucous membranes • Alcoholics in US • 3rd world countries

26. B-complex Vitamins • Niacin • Nicotinamide and nicotinic acid • Good sources: meat, fish, poultry, enriched bread products • Toxicity can result from supplements (not common) • Pellagra – severe niacin deficiency • Classic signs in an alcoholic when in a hospital setting • 4 classic signs: Diarrhea, Dermatitis, Dementia, Death • Seen in corn-based diets

27. B-complex Vitamins • Vitamin B6 (pyridoxine) • Group of 6 related compounds • Good sources: *enriched cereals, meat, fish, poultry, starchy vegetables • Toxicity from supplements can result in nerve damage, skin lesions • Alleviates PMS, carpal tunnel syndrome • Light sensitive container • **Imperative for metabolism for amino acids • Facilitate 100 enzymes necessary for amino acid metabolism • 25%-100% from diet source=cereals

28. B-complex Vitamins • Folate • Involved in DNA synthesis, amino acid metabolism, nucleotide synthesis • **Critical for cell division on early embryos (need an adequate amount before conception) • Women of child-bearing years need to supplement • Good sources: ready-to-eat cereals (primary source), enriched bread products • Toxicity can mask vitamin B12deficiency • “Abundant in foliage”

29. B-complex Vitamins • Vitamin B12 (cobalamin) • Part of coenzymes for blood formation • Found only in animal-based foods • We take in adequate or excessive amounts because of our meat-loving diet • Blood formation, nerve function, Homocysteine break-down—*key products needed to decrease risk of heart disease • Meat, fish, poultry, dairy, eggs (vegetarians need to supplement oftentimes) • Deficiency results in anemia, low energy, fatigue, shortness of breath, and can lead to pernicious anemia—occurs often with age b/c of lack of protein/ thus decreased HCL levelsatrophic gastritis, intrinsic factor, decreased absorption of B12

30. B-complex Vitamins • Pantothenicacid • “From everywhere” • Good sources: chicken, beef, egg yolk, potatoes, oat cereals, tomato products • No toxicity from excess pantothenic acid • Deficiencies are very rare

31. B-complex Vitamins • Biotin • Biotin content has been determined for very few foods • Liver, egg yolks, small amount in cooked cereals • Deficiency symptoms (rarely seen) include hair thinning, loss of hair color, red rash on face • Important for gluconeogenesis!!! (making glucose from non-carbohydrate sources) • Protein avidinprevents absorption

32. Iodine • Iodine is a trace mineral. • Supports energy regulation • Critical for the synthesis of thyroid hormones • Regulates body temperature • Regulates resting metabolic rate (RMR) • Good sources: saltwater fish, shrimp, *iodized salt (main source), milk and dairy products • Deficiencies: • Creatinism(inadequate amounts of saltmental retardation, stunted growth) • Goiter (hypothyroidism—decreased thyroid hormones) • Endemic hypothyroidims: iodine deficiency

33. Chromium • Chromium is a trace mineral. • *Assists in insulin as it transports glucose from the blood into the cells • Small amounts needed • Good sources: mushrooms, prunes, dark chocolate, beer, wine, nuts, whole grains • Chromium deficiency inhibits glucose absorption by body cells increased blood glucose level (very rare)

34. Manganese • Manganese is a trace mineral. • Coenzyme involved in energy metabolism • Part of the antioxidant enzyme superoxide dismutase (helps as a cancer fighting agent) • Good sources: whole-grain foods, brown rice, pineapple, pine nuts, okra, spinach • Toxicity impairs the nervous system causing spasms and tremors (very rare)

35. Sulfur • Sulfur is a major mineral. • Component of thiamine and biotin • Key role in detoxification (breakdown) of alcohol and drugs by the liver • Found in a few amino acids • Sufficient sulfur is synthesized from the protein in our diets

36. Vitamin K • Vitamin K is a fat-soluble vitamin. • Coenzyme for synthesis of proteins involved in blood clotting • Intestinal bacteria produces some K • Good sources: green leafy (dark) vegetables • Deficiencies can result in diseases that disturb absorption of fats • Can occur in some disease states as well as inadequate intake of dark leafy greens • Ex: Crohn’s disease, Cystic fibrosis, Celiac’s disease that isn’t controlled • Concern in the U.S.

37. Iron • Iron is a trace mineral. • Functions of iron • A component of the protein hemoglobin which carries oxygen in erythrocytes • A component of myoglobin which carries oxygen in muscle cells • *Coenzyme involved in energy metabolism of carbohydrates, fats, and proteins • #1 deficiency across the world since meat sources are a primary source & women lose iron every month • Need small amounts but essential for the survival of all cells

38. Iron

39. Iron • Iron can be stored in the body as: • Ferritin • Homosiderine • Usually stored in liver, bone marrow, intestinal mucosa, & spleen • Two types of iron are found in foods • Heme iron – found inanimal based foods and **more absorbable • Stored in the hemoglobin or myoglobin of meat • Non-heme iron – not easily absorbed (b/c of the fiber, amount, and accessibility to the body)

40. Iron • Recommended intake • RDA varies based on age and gender. • Adult Men: 8 mg/day • Adult Women: 27 mg/day (decreases post-menopausal) • Sources of iron • Meat (40% heme, 60% non-heme), poultry, fish (100% non-heme), clams (100% non-heme), oysters (100% non-heme), enriched cereals and breads (100% non-heme)

41. Iron • Iron Consumption • Iron deficiency is the most common nutrient deficiency in the world • High risk people include infants, young children, preadolescent girls, premenopausal women, and pregnant women • Bioavailability: 18% of a mixed diet of plant and animal diets will be absorbed • Plant based diets are 10% • Decreased absorption when taking in a lot of tannins (in teas) and calcium

42. Iron

43. Zinc • Zinc is a trace mineral. • Functions of zinc • Coenzyme for hemoglobin production • Part of superoxide dismutase antioxidant enzyme system • Helps fight free radicals • Assists in the digestion of CHO, fats, and proteins

44. Zinc • Recommended intake • RDA is 8 mg/day for women, 11 mg/day for men. • Sources of zinc • Red meats, some seafood, whole grains, enriched grains and cereals • Increased levels of non-heme iron (plant-based diet) inhibits zinc absorption • Body’s absorption of zinc goes from a 10% to a 35% periods of growth (infants, children, sexual development, and pregnancy)

45. Copper • Copper is a trace mineral. • Functions of copper • Part of superoxide dismutase antioxidant enzyme system • Required for iron transport • Helps with collagen production • Coenzyme for energy metabolism • Cancer fighting properties • Required for all iron transport

46. Copper • Recommended intake • RDA for adults is 900 mg/day. • Sources of copper • Organ meats (liver & onions), seafood, nuts, seeds, whole grain foods (most common for us) • Genetic concern where body does not utilize the copper given to it (Wilson’s disease) • Zinc supplements are given to help with the update of copper as well as low amounts in the diet

47. Anemia • Anemia means “without blood”; any condition of low hemoglobin levels. • Decreased oxygen in the body=fatigue & low energy levels • There are many types and causes of anemia including: • Iron-deficiency anemia (microsinic anemia) • Pernicious anemia (related to low levels of B12; prevalent in geriatric population) • Macrocyticanemia (related to low levels of folate) • Caused by nutrition inadequacies (primary anemia); some with a chronic disease state may have anemia as well—Cancer, Crohn’s, Rheumatoid Arthritis (Secondary anemia)

48. Anemia • Iron-deficient anemia • Symptoms are fatigue, pale skin, impaired work performance, depressed immune function, impaired memory • Results in small red blood cells that don’t carry enough hemegolobin • Look at serum iron level in lab tests • Normal: 60-170 mg/dL

49. Anemia • Pernicious anemia • Primary cause of vitamin B12 deficiency • Symptoms are pale skin, reduced energy, fatigue, neurological symptoms • Occurs after the loss of specific cells in the stomach or if individuals consume low levels of B12 in the diet • Low levels of intrin

50. Anemia • Macrocytic anemia • Results in enlarged red blood cells carrying insufficient hemoglobin • Shows common symptoms of anemia including weakness, fatigue, difficulty concentrating, irritability, headache, shortness of breath