Nutritional Requirements for Adults

NUTRITIONAL REQUIREMENTS 1  Learning objectives At the end of this session you are expected to Describe dietary reference intake(DRI) Explain factors affecting energy requirements Describe factors affecting nutrient requirement Explain nutritional and energy need...

NUTRITIONAL REQUIREMENTS 1  Learning objectives At the end of this session you are expected to Describe dietary reference intake(DRI) Explain factors affecting energy requirements Describe factors affecting nutrient requirement Explain nutritional and energy need at 2 different life stages  We eat food because our body need: energy; compounds for growth, repair and reproduction; substances to regulate the production of energy, growth and repair. hiwot The energy supply Foods containing… protein carbohydrate fat …provide the body with energy. hiwot The other functions Food also provides… fibre; water; vitamins and minerals. These substances do not provide the body with energy, but are all needed to fulfil some important ‘support’ functions for hiwot the body.  How is energy measured? Food Energy is measured in units known as kilojoules (kJ) and kilocalories (kcal). This is a different way of measuring energy, just as distance is measured in centimetres and inches. 1 kilocalorie =4.18400 kilojoules hiwot Energy and nutrients Food and drinks provide us with different amounts of energy because of the variety of nutrients they contain. 1g protein provides (4 kcal). 1g carbohydrate provides 4kcal). 1g fat provides (9 kcal). hiwot  Do all activities require equal amount of energy? Which type of food provide much energy? 8 Energy balance Is the balance of the energy consumed through eating and drinking compared to energy burned is the state at which the number of calories eaten equals the number of calories used. Energy balance is affected by physical activity, body size, amount of body fat and muscle. hiwot  Different people need different amounts of energy. It is important to balance the amount of energy we eat with the amount of energy we use up. Some activities use more energy than others. 10  Energy contribution These foods provide 400kJ of energy: hiwot  Energy in vs Energy out Number of minutes to use up 400kJ of energy: © British Nutrition Foundation 2004  Energy requirement Energy requirement is the amount of energy needed to maintain health, growth, and an “appropriate” level of physical activity. 13  Principles and Definitions Human energy requirements are estimated from measures of – energy expenditure plus the additional energy needed for (growth, pregnancy and lactation. Energy balance is achieved when – input (i.e. dietary energy intake) is equal to output (i.e. total energy expenditure), – plus the energy cost of growth in childhood and pregnancy, or the energy cost to produce milk during lactation 14  Components of Energy Requirements Human beings need energy for the following: 1. Basal metabolism: Basal Metabolic Rate (BMR) is the number of calories burned as the body performs basic (basal) life-sustaining function. Commonly also termed as Resting Metabolic Rate (RMR), – which is the calories burned if you stayed in bed all day. 15  Basal metabolism comprises functions that are essential for life, such as – Cell function and replacement – The synthesis and secretion of enzymes and hormones. – Transportation of proteins and other substances – The maintenance of body temperature; – Uninterrupted work of cardiac , respiratory muscles and brain function BM represents 45 to 70 % of daily total energy. 16  Components of Energy Requirements... 2.Metabolic response to food: Eating requires energy for – ingestion , digestion of food, – and for the absorption, transport, etc of nutrients. 17  Components of Energy Requirements… 3.Physical activity. This is the most variable and second largest component of daily energy expenditure next to BMR 4. Growth. The energy cost of growth has two components: – 1) the energy needed to synthesize growing tissues; and – 2) the energy deposited in those tissues. 18  Components of Energy Requirements... 5.Pregnancy. During pregnancy, extra energy is needed for – the growth of the foetus, placenta and various maternal tissues 6.Lactation. The energy cost of lactation has two components: 1) the energy required to produce that milk 2) the energy content of the milk secreted 19  Changes in energy requirements with age BMR, depends on the mass of metabolically active(muscle) tissue in the body, The changes in body composition with age, – markedly affect energy requirements BMR is higher during child hood and adolescent and becomes lower during old age 20  Sex differences in energy requirements Which sex requires more energy? 21  Sex differences in energy requirements Men have a relatively greater muscle mass than women The greater body fat content of women means that – BMR per unit total body weight is somewhat lower in women. 22  BMR Age Male Female (calories (calories per hour) per hour) 30–39 39.5 36.5 40–49 38.5 36.5 50–59 37.5 35.0 60–69 36.5 34.0 23 NUTRITIONAL REQUIREMENT  Nutritional Requirement “ is defined as the The amount of each nutrient needed These are different for each nutrient and also vary between individuals and life stages, – e.g. women of childbearing age need more iron than men. 25 Why is it Important to Know the Nutritional Requirement?  Knowing Nutritional requirements are needed most especially for a) Prescriptive reasons:- – to Design nutrition education programs, – to procure food for national consumption, – To secure food for institutional consumption and – to run nutritional supplementation 27 b) For Diagnostic Reasons: - for identifying – whether a group or an individual is suffering from malnutrition of any kind or not. These include assessment nutritional status, – to evaluate nutritional intervention programs, – to determine whether the food available in the stock is adequate to feed the household, nation for certain duration of time etc  Dietary Reference Intakes (DRI) DRI’s are quantitative estimates of nutrient intake to be used for planning and assessing diets of healthy people Include: Estimated Average Requirement (EAR) Recommended Dietary Allowance (RDA) Lower Reference Nutrient Intake ( LRNI) Adequate Intake (AI) Tolerable Upper Intake Level (UL) 29  Estimated average requirement (EAR) : This is an estimate of the average requirement for energy or a nutrient It satisfies the energy and nutrient need of 50% of the population approximately 50% of a group of people will require more The EAR is used in particular for energy. 30  Recommended dietary allowance(RDA) Is the daily intake, which meets the requirements of – almost all (97.5 percent) apparently healthy individuals in age and sex-specific population group. RDA s are used mainly for – protein, vitamins and minerals. 31  Lower Reference Nutrient Intake (LRNI) The amount of a nutrient that is enough – for only the small number of people (2.5%) The majority of the population need more 32  Adequate intake (safe intake): These values are based on – observed or experimentally determined estimates of nutrient intake by a group (s) of healthy individuals. At this level there is no risk of deficiency and is below the level where it causes toxicity. 33  Upper tolerable nutrient intake level Are the maximum intake from food that is unlikely to pose risk of adverse health effects in almost all (97.5 %) apparently healthy individuals in an age and sex- specific population group 34 EARs, RDA/AIs and ULs for an average healthy adult males aged 30-50 years old are shown below Nutrient EAR RDA/AI UL Unit Vitamin A 625 900 3000 µg Vitamin C 75 90 2000 mg Vitamin D 10 15 100 µg Vitamin B6 1.1 1.3 100 mg α-tocopherol(Vitamin E) 12 15 1000 mg Calcium 800 1000 2500 mg Copper 700 900 10000 µg Folate (B9) 320 400 1000 µg Iodine 95 150 1100 µg Iron 6 8 45 mg Phosphorus 580 700 4000 mg Thiamin (B1) 1.0 1.2 ND mg Zinc 9.4 11 40 mg 35 DRI Scientific Basis for Establishing DRIs  Observed intakes in healthy populations  Epidemiological observations (Researches)  Animal experiments  Biochemical measurements 37 Diet planning for an adult in a group It has to be a healthy diet – Fulfills energy needs (macronutrients) – Provides sufficient amounts of essential nutrients (micronutrients) – Reduces risk of disease – Is safe to consume (low contaminants or potentially harmful added substances) 38  Criteria for selecting food items – Meeting the calorie requirement – AMDR(Acceptable macronutrient distribution range) – Dietary diversity – Availability in the market – Health condition – physiological status – Likes/dislikes – Affordability 39  Determining energy need Estimated Energy Requirement (EER) – Average dietary energy intake (kcal) to maintain energy balance – Based on age, sex, weight, height, level of physical activity For men EER = 662 – (9.53 X AGE) + PA X (15.91 X WT + 539.6 X HT) For Women EER = 354 – (6.91 X AGE) + PA X (9.36 X WT + 726 X HT)  Physical activity (PA) For men women Sedantary 1 1 Low active 1.12 1.14 Active 1.27 1.27 Very active 1.54 1.45 41 Level of DESCRIPTION PA · Activities of daily living only, such as shopping, cleaning, watering plants, taking out the trash, walking the dog, sedenta mowing the lawn, and gardening. ry · No moderate or vigorous activities. · Unless you do at least 30 minutes per day of intentional exercise, you are considered sedentary. · Activities of daily living, such as shopping, cleaning, watering plants, taking out the trash, walking the dog, mowing the lawn, and gardening. · Daily exercise that is equal to walking for 30 minutes at Low 4 miles per hour. For an adult of average weight, this Active amount of exercise will burn about 135 to 165 additional Calories. · More intense exercise can be performed for less time to achieve the same goal. For example, 15 or 20 minutes of vigorous activity, such as aerobics, skiing, or jogging on 42 a  If you're Active, your daily activities include: · Activities of daily living, such as shopping, cleaning, watering plants, taking out the trash, walking the dog, mowing the lawn, and gardening. Active · Daily exercise that is equal to walking for 1 hour 45 minutes at 4 miles per hour. For an adult of average weight, this amount of exercise will burn about 470 to 580 additional Calories. · More intense exercise can be performed for less time. For example, jogging for 50 minutes per day. If you're Very Active, your daily activities include: · Activities of daily living, such as shopping, cleaning, watering plants, taking out the trash, walking the dog, mowing the lawn, and gardening. Very · Daily exercise that is equal to walking for 4 hours 15 Active minutes at 4 miles per hour. For an adult of average weight, this amount of exercise will burn about 1145 to 43 1405 additional Calories.  Class work Calculate the EER of yourself 44  Determining Nutrient Needs for macro nutrients Acceptable Macronutrient Distribution Ranges (AMDR) – Describes the portion of the energy intake that should come from each macronutrient  AMDR Acceptable macronutrient distribution ranges (AMDRs) for carbohydrate, fat, and protein have been set by considering epidemiological evidences that suggest consumption within these ranges plays a role in reducing risk of chronic diseases. 46  AMDR – Expressed as ranges (percentage of total energy) with upper and lower boundary. Recommended AMDR – Carbohydrate=45%-65%, acceptable up to 70% – Fat=20-35% – Protein =8-10% 47 Dietary Guidelines Versus DRIs  Dietary Guidelines – Qualitative advice to the public about diet and chronic disease prevention (e.g., the Food Pyramid)  DRIs – Quantitative advice to professionals about amounts of nutrients needed. 48 49 CHO, protein and fat composition of teff compared to maize, sorghum, wheat and rice Teff maize sorghum wheat rice Energy 357 375 370 359 357 (kcal) Starch 73 72 63 71 64 (%) protein 11 8-11 8.3 11.7 7.3 (%) fat(%) 2.5 4.9 3.9 2 2.2 fiber 3 1.6 0.6 2 0.6-1 50 Mineral content of teff grain compared to other cereals, mg/100g Miner White Red Mixed Maiz Sorgh Whea Ric als teff teff teff e um t e Iron 9.5- 11.6- 11.5- 3.6- 3.5- 3.7 1.5 13.7 15.0 15.0 4.8 4.1 Zinc 2.4-6.8 2.3-6.7 3.8-3.9 2.6- 1.4- 1.7 2.2 4.6 1.7 Calciu 17-24 18-28 8.8-14.7 16 5.0- 15.2- 23 m 5.8 39.5 Coppe 2.5-5.3 1.1-3.6 1.6 1.3 0.41 0.23 0.16 r 51 52  Nutrient content of different types of breads, per 100 g Wheat bread, Rye bread, Wheat bread Rye bread wholemeal wholemeal Carbohydrates, g 49 41 41 39 Protein, g 8 8 5 7 Fat, g 1 1 1 1 Dietary fibre, g 3 7 7 8 Vitamins Vitamin B1 (Thiamine), 86 150 180 180 µg Vitamin B2 60 150 51 150 (Riboflavin), µg Vitamin B3 (Niacin), 2.2 5.0 1.8 1.6 mg Vitamin B6 17 79 80 150 (pyridoxine), µg Vitamin B9 (Folate), µg 22 29 16 14 Minerals Iron, mg 0.7 2.0 1.6 2.0 Zinc, mg 0.7 1.5 1.5 1.5 Magnesium, mg 24 60 46 55 53 banana 54  Nutritional Requirement during Critical Periods 55  There is Special nutrient requirement during: – Preconception – Pregnancy – Lactation – Infancy, adolescence … – Old age These groups are Vulnerable to malnutrition b/c – inadequacy plus – special requirement And it is an intergenerational 56 Preconception nutrition(Nutrition Before Conception) 57 A healthful diet before conception includes: – Avoiding teratogens: substances that cause birth defects Includes alcohol – Avoiding other possible hazards Smoking, caffeine, medications, some herbs and supplements preconception  Nutrition Before Conception A healthful diet before conception reduces the risk of developing nutrition-related disorders during pregnancy, such as: – Gestational diabetes – Pre-eclampsia preconception  Other Preconception Nutrition Concerns Some deficiency related problems develop very early in pregnancy. – Folate status prior to conception – neural tube defects Adequate folate (400 µg daily) before conception can reduce the risks preconception 60  Folate status prior to conception Folate status prior to conception is important – because inadequate folate status very early in pregnancy can cause Neural Tube Defects. Neural Tube Defects Develop within 21 days after conception (generally occurring between days 18-29 of gestation ) before women even know they are pregnant and before Antenatal care begins Folate status should be optimal before conception Major Nutritional concern in the preconception period preconception 61 Folate status prior to conception Folate supplements taken one month before conception and continued throughout the first trimester of pregnancy can help prevent neural tube defects. Neural tube defects – malformation of the brain, spinal cord or both during embryonic development that result in lifelong disability or death. preconception 62  Neural Tube Defects 1. Anencephaly: the brain is absent or fails to develop. 2. Spinabifida: incomplete closure of the spinal cord (split spine) – Mild cases may not be noticed but sever cases lead to death – Accompanied by varying degrees of paralysis depending on the severity of the defect. – Other problems include dislocated hip, kidney disorder, curvature of the spine, muscle weakness. 3. Encephalocele: the brain protrudes through the gap in skull.it results in leakage of fluid from around the brain,(CSF leak) preconception 63 Neural Tube Defects preconception 64 Neural Tube Defects 65 Weight status Underweight increases the risk of maternal complications during pregnancy and the delivery of small and pre-term babies Overweight increase the risk of clinical complications during pregnancy and delivery of new born with excessive fat preconception 66 Weight Loss and Fertility Weight loss >10-15% of usual weight decreases estrogen, FSH, LH levels. Consequences of these hormonal changes include Amenorrhea and Anovulatory cycles Short or absent luteal phases (ovulation to day of the menstrual cycle) Treatment with fertility drugs is not effective in underweight women Weight gain is recommended first line Rx preconception 67  Weight Loss and Fertility Hormonal levels return to normal when 95% of previous weight is regained. Weight loss also decreases fertility in Males. Studies from World War II showed 50% reduction in caloric intake during starvation resulted in a decrease in male fertility. Sperm viability & motility decrease when weight was 10 to 15% less than normal. Sperm production cease at a weight loss greater than 25% of normal weight. preconception 68  Body Fat and Fertility Decreased fertility seen with low or high body fat due to alterations in hormones in men Obesity reduces testosterone levels and infertility treatments are less effective in obese men. preconception 69  Body Fat and Fertility Weight loss is the initial treatment for infertility in men and women with high body fat. Low body fat has been associated with a delayed onset of menstruation. Generally fertility is compromised in women with BMI 30 preconception 70 Pregnancy preconception 71  Pregnancy Pregnancy is considered physiological if mothers: Produce a healthy baby with appropriate weight at birth Produce enough milk ( >750g/day in the first 6 months) and of good quality for the growth of exclusively breast fed infants during the first 6 months Mothers’ nutritional status is not 72  Prenatal nutrition is affected by: --Nutritional status prior to pregnancy and during pregnancy - Maternal age- adolescents need more calories - Parity 73  Pregnancy Increased requirements for energy & nutrients for Formation of tissue- placenta, fetus, amniotic fluid Increase in tissue -uterus, blood volume, breast & fat deposition Other changes- increased BMR So Adequate nutrition before & during pregnancy is essential for its progress & outcome. 74  There is strong evidence for r/ship b/n pre- pregnancy weight & weight gain during pregnancy and mortality during pregnancy. -ve outcomes of pregnancy- are more common in poorly nourished women Abortions, stillbirths & fetal malformations, morbidity & mortality (perinatal, infant & maternal), impaired growth & psycho-motor developments 75  Pregnancy Weight gain is essential to the well being of the developing fetus First 2 trimesters – Anabolic ( growth of breasts, uterus/placenta production of amniotic fluid, increased in blood volume & deposition of body fat). – The fetal growth is slow 76 Later trimester – Fetal growth- tripling of weight b/n 28 & 40 wks (1000g to 3200-3600g) – Catabolic for mother- uses fat stores – If her intake is not sufficient –her store will be depleted – the most vulnerable period for the fetus in terms of birth weight 77  Pregnancy A well nourished woman before pregnancy is expected to gains – ~20% (11-16kg) of her pre-pregnant weight during pregnancy 1st trimester- 1 to 2 kg & then 0.5 kg/wk – 60% attributable to maternal weight gain- fluid volume, protein & fat deposition – 40%-attributable to fetus, placenta, & amniotic fluid,fetus The required weight gain depends on pre- pregnancy status  Recommended weight gains based on pre- pregnancy weight _______________________________________________________ Pre pregnancy weight Recommended weight gain (kg) First trimester Total wt gain _______________________________________________________ Underweight (BMI