ENERGY BALANCE ENERGY INTAKE ENERGY EXPENDITURE. BMR Physical activity SDA of Food. 1 kcal = 4,182 kj

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1 Nutrition

2 Energy Balance

3 ENERGY BALANCE ENERGY INTAKE ENERGY EXPENDITURE BMR Physical activity SDA of Food 1 kcal = 4,182 kj

4 THE BASAL METABOLIC RATE The least amount of energy required by the resting human body to keep normal functions of the most important life processes BASAL CONDITIONS: At least 12 hours after the last meal Several hours after strenuous exercise After a night of restful sleep Comfortable temperature of the air BMR the average adult -1 kcal/kg body weight/hour kcal/m2/hour Factors affecting BMR: Age Pregnancy Sex Body composition Hormonal profile Undernourishment Life style Body temperature THE TOTAL ENERGY NEED (TMR): BMR S.D.A. /Specific dynamic action of food/ Activity physical activity /everyday activities, special activities work, exercise/

5 The term "physical activity" should not be mistaken with "exercise". Exercise, is a subcategory of physical activity that is planned, structured, repetitive, and purposeful in the sense that the improvement or maintenance of one or more components of physical fitness is the objective. Physical activity includes exercise as well as other activities which involve bodily movement and are done as part of playing, working, active transportation, house chores and recreational activities. (

6 Total Metabolic Rate Men 1. Body weight x 24 hours = BMR 2. BMR x Activity = TMR Women 1. Body weight x 24 hours = BMR 2. BMR x 0,9 = Corrected BMR 3. Corrected BMR x Activity = TMR

7 Activity: 1.2 Sedentary Light Exercise (1-3 /week) 1.55 Regular exercise (3-5 /week) Daily exercise (6-7 /week) Athlete

8 ENERGY INTAKE ENERGY EXPENDITURE ENERGY IMBALANCE OVERWEIGHT or OBESITY

9 Statistics!!! in 2005, 1.6 billion - overweight million - obese to 2015, probably 2.3 billion - overweight million - obese

10 BMI - defined as a person's weight in kilograms divided by the square of his height in meters (kg/m2). Underweight BMI 18,5 Normal BMI = 18,5-24,9 Overweight BMI = 25-29,9 Obesity BMI > 30

11 Waist circumference is a helping indicator of visceral fat this fat is the most metabolically active and thus the most harmful Women cm Men >88 cm = highly increased risk 1 >80 cm = increased risk 1 >102 cm = highly increased r >94 cm = increased risk 1 1 Lean MEJ, et al. Lancet;1998:351:853 6

12 Raised BMI is a major risk factor for noncommunicable diseases such as: cardiovascular diseases (mainly heart disease and stroke) diabetes musculoskeletal disorders (especially osteoarthritis a degenerative disease of the joints); some cancers (endometrial, breast, and colon). 44% of the diabetes burden, 23% of the ischaemic heart disease burden and between 7% and 41% of certain cancer burdens are attributable to overweight and obesity. (

13 Causes? In 90% - positive energy balance

14 ENERGY IMBALANCE OBESITY AND OVERWEIGHT ENERGY INTAKE ENERGY EXPENDITURE an increased intake of energy-dense foods that are high in fat, salt and sugars but low in vitamins, minerals and other micronutrients a decrease in physical activity due to the increasingly sedentary nature of many forms of work, changing modes of transportation, and increasing urbanization (

15 How to prevent??? 1. Eat healthy!

16 Be active! How to prevent???

17 Regular and adequate levels of physical activity in adults: reduce the risk of hypertension, coronary heart disease, stroke, diabetes, breast and colon cancer, depression; improve bone and functional health; and are a key determinant of energy expenditure, and thus fundamental to energy balance and weight control. (

18 How to prevent??? 3. Reduce stress

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20 Pyramids of Food Plate Physical activity

21 WHY DO WE NEED CARBOHYDRATES? Major source of food energy Glucose - principal energy source (nervous cells, red blood cells) Glycogen - 1 % of total body caloric stores (liver g, muscle g) Necessary for lipid metabolism Components of glycolipids, glycoproteins (basement membrane collagen, mucopolysaccharides, nerve cell myelin, hormones, hormone receptors) May contain dietary fibres (cellulose, pectin, gums) Maintain good intestinal motility Bind toxins, cholesterol

22 Water Soluble Vitamins

23 Vitamin B1 (thiamine pyrophosphate) Decarboxylation of -keto acids (pyruvate, -ketoglutarate) Transketolation (pentose phosphate pathway) Adult RDA 1,1 mg (women), 1,5 mg (men) Unstable to oxidation, heat

24 Deficiency -beriberi (Singhalese I can t, I can t)

25 Glucose Pyruvate Lactate Acidosis Acetyl- CoA level of high energy compounds (ATP) Peripheral vasodilatation Cardiac failure Neurons (CNS) chromatolysis, swelling Degeneration of myelin sheaths Manifestations of encephalopathy and/or polyneuropathy

26 Deficiency -beriberi (chronic, adults) Dry - neurologic changes (peripheral) bilateral, symmetric lower extremities muscle weakness, tenderness positive squat test Cerebral Korsakoff S. confusion, aphonia Wernicke S. nystagmus, ophthalmoplegia, coma Wet blood vessels dilation cardiac failure primary weakness high blood flow heart muscle enlargement edema Mixed (Singhalese I can t, I can t)

27 Vitamin B2 (riboflavin) flavin mononucleotide - FMN, flavin adenine dinucleotide - FAD coenzymes of flavoproteins Deficiency: Oral changes Skin changes Eye changes Cheilitis red, chapped, dry lips Dry, scaly, greasy skin Conjunctivitis Angular stomatitis Dermatitis Superficial opacities, /corners - cracks, fissures, crusts/ /face, groin, genital areas/ ulcerations Glossitis smooth, red tongue, Lacrimation, photophobia flat, swollen, pebbled papillae Sources: PLANTS: whole grains, peas, yeast, peanuts, ANIMALS: liver, meat, fish, milk Very unstable to sunlight Adult RDA: 1,3 mg (women), 1,7 mg (men)

28 Vitamin B6 (pyridoxal phosphate) Deficiency Amino acid metabolism Tryptophan serotonin, niacin Glycogenolysis Linoleic acid arachidonic acid Sphingolipid synthesis GABA metabolism Convulsions Adult RDA: 1,6 mg (women), 2 mg(men) (unstable to alkali, ultraviolet rays, oxidation) Source: salmon, liver, meat, yeast, whole grains

29 Vitamin C (ascorbic acid) A reducing agent (a redox system); An antioxidant Necessary for hydroxylazes Essential for collagen synthesis Helps maintain the integrity of connective tissue, osteoid, dentin Synthesis of adrenal steroid hormones, epinephrine, bile acids Keeps iron in ferrous form iron absorption, activates folic acid Adult RDA - 60 mg

30 Bone lesions; defective ossifications, fractures, Cessation of bone growth Vitamin C (ascorbic acid) Deficiency - scurvy Gingivitis Secondary infection, gangrene Loosening of teeth Fragility of vessels walls pinpoint (petechial) haemorrhages, perifollicular petechiae, ecchymoses, bruises, hemorrhages (skin, muscles, gums, joins) bleeding from mucous membranes Weak, defective intercellular cement substances: subcutaneous tissue, bone, teeth, cartilage, blood vessel walls

31 Niacin (B3) nicotinamide adenine dinucleotide (NAD) nicotinamide adenine dinucleotide phosphate (NADP) coenzymes of dehydrogenases Deficiency pellagra (4 D`s disease) Decreased delivery of energy to the functioning elements of the cells - lesions dermatitis dementia depression diarrhea Sources: Animal: meat, poultry, fish, yeast, peanut Plant: legumes, nuts GI tract bacteria Tryptophan (+ B1, B2, B6) Moderately stable Adult RDA: 15 mg (women), 19 mg (men)

32 Folic acid and B 12 deficiency

33 Folic acid (folate, folic acid and folacin) THFA - a one-carbon groups carrier DNA synthesis (purines, thymine) Replication of cellular genes, promotion of growth Amino acids metabolism (serine, glycine, homocystine, methionine, tyrosine, histidine) Phospholipids metabolism (cholin synthesis)

34 Megaloblastic anemia Folic acid Deficiency GI manifestations (glossitis, diarrhea) CNS defects (spina bifuda) fetus Adult RDA: 0,4 mg (?) Stored (liver) Destroyed by overcooking, stable in acid solutions

35 Vitamin B 12 (cobalamin) Folic acid conversion to its coenzyme form (THFA) Synthesis of thymidine (DNA) Replication of cellular genes Promotion of growth Promotion of red blood cells formation and maturation Homocysteine methionine Adult RDA: 2 µg Stored (liver)

36 Vitamin B 12 Deficiency - pernicious anaemia Neurological symptoms Demyelination Degeneration Sensation disturbances, muscle weakness Memory loss, depression ( intrinsic factor) Cholin synthesis GI manifestations Glossitis Atrophic gastritis DNA synthesis Megaloblastic anaemia

37 WHY DO WE NEED LIPIDS? Contain nutrients - essential fatty acids, fat-soluble vitamins Linoleic acid and linolenic acid Regulation of cholesterol metabolism Maintenance of functions, integrity of cell membranes Synthesis of prostaglandins, thromboxanes, prostacyclins, leukotrienes Concentrated sources of energy (should provide % of daily dietary requirement for energy) Thermal insulation, protection against injury, trauma Account for most of body s stored energy (15% body weight - males, 25% body weight-females) Increase the satiety value of food (!)

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39 Fat Soluble Vitamins

40 Vitamin A (retinol, retinal) Photoreceptor pigments Antioxidant Cells growth, proliferation, differentiation Epithelial structure, function Mucus secretion Adult RDA: 5000 IU (1 g of retinol = 3,33 IU, 1 IU = 0,3 g of retinol) Preformed Sources: Provitamins (carotenes) Orange, yellow pigments 1 g of -carotene = 0,167 g of retinol

41 Eye manifestation: Night blindness (nyctalopia) Deficiency Dryness of conjunctiva, cornea (xerosis) Blocked tear ducts Xerophthalmia Keratomalacia (softening, necrosis of cornea) Blindness Epithelial degeneration (keratinization) Secondary infections Follicular hyperkeratosis

42 Acute toxicity (> 100,000 µg or 300,000 IU - children) Chronic toxicity > 33,000 µg - 100,000 IU/day for months - older children, adults, 6,000 to 20,000 µg (20,000 to 60,000 IU)/day of water-miscible vitamin A- infants within a few weeks, Massive doses (50,000 to 120,000 µg or 150,000 to 350,000 IU) of vitamin A or its metabolites are given daily to persons with acne (a risk - vitamin A toxicity).

43 Vitamin D (1,25(OH) 2 D 3 calcitriol) intestinal absorption of calcium and phosphate Facilitates action of PTH on mobilizing calcium ions Deficiency Slow, faulty development of bones, teeth Soft, deformed bones Rickets (Children) Osteomalacia (Adults) Source: ANIMALS: liver of fish, animals, fish, milk, egg yolk - cholecalciferol - D 3 1,25(OH) 2 D 3 produced from 7-dehydrocholesterol in human body PLANTS: vegetables, fruits, cereal ergocalciferol - D 2 Adult RDA 200IU - 400IU

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46 Vitamin E ( -tocopherol) An antioxidant ; Prevents oxidation of fat (PUFAs), vitamin A, C, Maintenance of cell membranes (erythrocytes, hepatocytes, muscle cells, spermatogenesis) Deficiency Abnormalities of muscle, liver, bone marrow, brain function, reproduction Hemolytic anemia Spinocerebellar desease Source: Fats, oils; butter, margarine, meat, chiken, fish, green leafy vegetables, germ of cereals Destroyed by oxidation RDA: 8 mg (women), 10 mg (men)

47 Vitamin K Hepatic formation of clotting factors (II, VII, IX, X) Deficiency Retarded blood clotting bleeding hemorrhagic d. of the newborn late hemorrhagic d. Sources: Green vegetables Intestinal bacteria Sensitive to acid, alkali, light, oxidation Adult RDA µg (women), µg (men)

48 WHY DO WE NEED PROTEINS? Dietary - provide essential amino acids Structural components Enzymes, hormones, neuromodulators, neurotransmitters Transporters for oxygen (hemoglobin) Regulator of plasma (colloid) osmotic pressure - albumin A buffer system - albumin and hemoglobin Transporters (albumin, globulin) Antibodies (globulin) A precursor (tryptophan) for vitamin (niacin) Components of chromatin (nucleoproteins) Energy source (10-15% of daily energy intake should come from proteins) Requirement - 0,8g - 1,0 g of mixed proteins/kg body weight/day - determined by: body size, age, pregnancy, lactation, hormonal profile, nervous system state, activity, nutritional status, diseases, biological value of protein

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