Food and Health Saturday, 7 March 2015

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11:36 am

Shift from nutrient deficiency focus Move to emphasis on chronic disease prevention Future - sustainability and food security Science of human nutrition is not the only influence to what we eat or are recommend to consume (e.g. availability of food)

How does food consumption affect health? • Limitations of looking at individual components of the diet such as specific foods and nutrients. • Dietary patterns provide a better context for determining whether diet has an impact on health. However the specific component that causes these impacts cannot be determined unlike when investigating individual foods and nutrients. • Not necessary to eliminate food groups or conform to a single dietary pattern to achieve healthy dietary patterns • Individuals can combine foods in a variety of different ways to achieve healthy dietary patterns - should be tailored to individuals

How does nutrition practice and research relate to food policy? • Nutritional Health of Population ○ Health services to the community ○ Public Health agency (e.g. government) ○ Nutrition research ○ Food industry Food Innovation

Food Philosophy • An approach to food influenced by ideals and values ○ Health effects ○ Moral/ ethical issues ○ Sustainability Religion NUTR1230 Page 1

Dietary Guidelines Monday, 16 March 2015

12:06 pm

What are the Dietary Guidelines • The Australian Dietary Guidelines provide up-to-date advice about the amount and kinds of foods that we need to eat for health and wellbeing. They are based on scientific evidence and research Guideline 1: • To achieve and maintain a health weight, be physically active and choose amounts of nutritious food and drinks to meet your energy needs ○ Older people should eat nutritious foods and keep physically active to help maintain muscle strength and a healthy weight Guideline 2: • Enjoy a wide variety of nutritious foods from these five food groups every day: ○ Plenty of vegetables of different types and colours and legumes/ beans ○ Fruit ○ Grain (cereal) foods, mostly wholegrain and/or high cereal fibre varieties, such as breads, cereals, rice, pasta, noodles, polenta, couscous, oats, quinoa and barley ○ Lean meats and poultry, fish, eggs, tofu, nuts and seeds and legumes/beans ○ Milk, yoghurt, cheese and/or their alternatives, mostly reduced fats • And drink plenty of water Guideline 3: • Limit intake of foods containing saturated fat, added salt, added sugars and alcohol • Limit intake of foods high in saturated fat such as many biscuits, cakes, pastries, pies and other savoury snacks ○ Replace high saturated fat foods such as butter, with foods containing polyunsaturated and monounsaturated fats such as oils, avocado and nut butter/pastes • Limit intake of food and drink with added salt, choose low sodium alternatives, do not add salt to food in cooking or at table • Limit food intake of foods containing added sugars such as confectionary, sugar sweetened soft drinks and cordials, fruit drinks, vitamin waters and sports drinks • If you choose to drink alcohol, limit intake. For women who are pregnant, planning a pregnancy or breastfeeding, not drinking alcohol is the safest option

Guidline 4: • Encourage, support and promote breastfeeding Guidline 5: • Care for your food; prepare and store it safely EAR (estimated energy requirement) • A daily nutrient level estimate to meet the requirements of half the healthy individuals in a particular life stage and gender group RDI (recommended daily intake) • The average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97-98 per cent) healthy individuals in a particular life stage and gender group

UL (Upper level) • The highest average daily intake likely to pose no adverse health effects to almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects increases. NUTR1230 Page 3

adverse effects increases.

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Limitations • EAR can be based on studies with limited numbers of individuals • Precise variation in nutrient requirements is not known • Assumption that the curve of requirement is normal • EARs may have been extrapolated from one population group to another • The degree of uncertainty has not been specified but that uncertainty has been applied at a RDI calculation • Scientific basis of the NRVs is not as strong as many people think • The targets for chronic disease prevention are focussed on heart disease and some cancers they are not comprehensive Diet Assessment • Diet history interview • Food records • 24-hour recall • Food frequency questionnaire • Short questions • Online dietary assessment

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Protein Timing • 2 serves of 40g every 8 hours for 12 hours • 4 serves of 20g every 3 hours for 12 hours • 8 serves of 10g every 1.5 hours for 12 hours • 6 biopsy's were taken over the 12 hour period • Maintain blood glucose concentration at the optimum levels for muscle repair, growth maintenance

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Protein Timing and Distribution • Optimal protein synthesis occurred when 20g of protein was ingested every 3 hours High Protein intake • Protein intake in excess of requirements may not be necessarily be stored as fat • Kidneys get rid of excessive nitrogen therefore can be at risk if you intake excessive amounts of protein and have kidney problems • In study of resistance trained individuals, high protein diet led to an increase in fat free mass compared to the control group on a regular diet

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Carbohydrates Monday, 30 March 2015

9:59 am

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Provide energy, particularly during high-intensity exercise Regulate fat and protein metabolism Exclusive energy source for the nervous system Synthesized into muscle and liver glycogen Glycogen is an aerobic fuel source and does not require oxygen to be burnt, unlike fat Some forms of glucose are absorbed slowly into the bloodstream, others are absorbed quickly (for example sugars in coke is taken up very rapidly compared to a banana) • Sources include grains, fruit, vegetables, milk and sweets Carbohydrates • Monosaccharides - glucose, fructose, galactose - simplest form of carbohydrate • Disaccharides - sucrose, lactose - two monosaccharides • Oligosaccharides - malto-oligosaccharides • Polysaccharides - starch, glycogen Disaccharides • Pairs of three monosaccharides ○ Maltose - two glucose units ○ Sucrose - glucose and fructose ○ Lactose - galactose and glucose • Condensation ○ Links two monosaccharides together • Hydrolysis ○ Breaks a disaccharide in two Glycogen and Starch Compared • Glycogen is a storage form of glucose in animals • Starch is the storage form of glucose in plants Fibre • Indigestible polysaccharides ○ Soluble fibres ○ Insoluble fibres ○ Resistant starches • Fills you up and prevents you from looking for energy dense foods high in calories and fat Starch and Cellulose (types of fibre) • Cellulous has resistant type bonds which can only be broken down by certain organisms such as cows Characteristics, Sources and Health Effects of Fibres • Soluable ○ Food sources - Barley, oats, fruits, legumes and many vegetables ○ Types of Fibres - Gums, Pectins (found in skin of fruit for example) ○ Lower risk of heart disease ○ Lower risk of diabetes ○ Lower risk of colon and rectal cancer ○ Increased satiety and may help with weight management • Insoluble ○ Food sources - Brown rice, fruits, legumes, seeds and whole grains ○ Types of fibres - cellulose, lignins (found in cores of fruits) Alleviate constipation NUTR1230 Page 8