Avocados

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Avocados
Human Nutrition HLTH 2001 Random Facts

• In the Guinness Book of Records as the most
  nutritious fruit known to man
• Unique in that it only ripens once picked
• Contain monounsaturated fat
• Source of antioxidants vit A, C and E
• Contain folate (impt during pregnancy)
• potassium (impt for fluid balance)
• Good source of protein, vit B6
• Low in sodium
• High in fibre

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Human Nutrition Lecture 2 Dietary Adequacy
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Revision

• Whitney Rolfes
• Understanding Nutrition, 10th Ed. 2005
• Appendix E to revise why different types of
  assessment are conducted
• eg FFQ vs 24 hr recall
• Health history vs biochemical assessment

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Dietary Adequacy

• Dietary Reference Intakes
• Standards that define the amounts of
• Energy
• Nutrients
• dietary components
• physical activity
• that BEST SUPPORT HEALTH

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• RDA/RDI vs NRVs
• RDA (American)- text book
• Recommended Dietary Allowance
• Recommended Daily Allowance
• RDI (Australian)
• Recommended Dietary Intake ?
• Recommended Daily Intake
• NRVs (New Australian Standards)
• Nutrient Reference Values

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Australian Standards

• RDI - recommended dietary intake
• Nutrient Reference Values
• Revised 2006
• Dietary Guidelines for Australians

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• Definition of RDI
• The levels of intake of essential nutrients
  considered to be adequate to meet the known
  nutritional needs of nearly all healthy people.

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RDIs

• Established in 1991 and revised in 1997
• Population based
• age/gender categories
• generous allowance to include variation in
  digestion absorption

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• the attached a URL (hyperlinked) is for The
  Australian Dietary Guidelines in case you want to
  look at them more closely
• for children adolescents in Australia
• for Australian adults
• The guidelines have recently been reviewed.

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Dietary Guidelines for Australians
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Final Outcome
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Nutrient Reference Values (NRVs)
NRVs for Australia and NZ released in 2006
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Nutrient Reference Values (NRVs)

• The NRVs are made up of the following  
• Estimated average requirements (EAR)
• Recommended dietary intake (RDI)
• Recommended Dietary Allowance (RDA) in USA and
  thus in textbook
• Adequate intakes (AI)
• Upper limits (UL)
• Suggested dietary targets (SDTs)
• Estimated energy requirement (EER)
• Acceptable macronutrient distribution range (AMDR)

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Estimated average requirements (EAR)

• The amount of a nutrient estimated to meet the
  requirements of half the healthy individuals of a
  particular age and gender.
• This value is the median usual intake of the
  population.
• Once the EAR was set, an RDI could be derived

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Recommended dietary intake (RDI)

• The average amount of a nutrient needed each day
  to meet the requirements of nearly all healthy
  individuals of a particular age and gender.

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RDIs
RDI EAR 2SDEAR
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Adequate intakes (AI)

•   Used when an EAR and therefore RDI cannot be
  determined because of limited or inconsistent
  data.
• RDIs are derived from EARs. When the EAR is not
  known or is unclear, AIs based on the mean intake
  of the population known not to have a deficiency
  has been adopted.

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Upper limits (UL)

• ULs have been set to avoid toxicity or other
  symptoms.
• Tolerable Upper Intake Level
• The maximum daily amount of a nutrient that
  appears safe for most people ad beyond which
  there is an increased risk of adverse health
  effects

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How these terms are Applied
Although NRVs are expressed on a PER DAY basis,
they should apply to intakes assessed over a
period of 3-4 days
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Suggested dietary targets (SDTs)

• The amount of a nutrient required to prevent or
  reduce the risk of chronic disease.

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Estimated Energy Requirement (EER)

• The average amount of energy (kJ) predicted to
  maintain weight and good health for a healthy
  adult of  a particular
• age,
• gender
• weight
• height
• level of physical activity

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Acceptable Macronutrient Distribution Range
(AMDR)

• The estimated range required for each
  macronutrient that would allow for an adequate
  intake of all other nutrients, whilst maximising
  general health.
• expressed as a contribution to energy
• Eg 45 Carbohydrate

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Old RDIs vs New NRVs

• RDI is just one component of the NRVs
• There are now recommendations for a wider range
  of nutrients

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Nutrients that are Included in the NRVs















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Old RDIs vs New NRVs

• Nutrients which have recommendations for the
  first time are
• Fibre - while recommendations for fibre did exist
  previously, they were not included as part of the
  old RDIs.
• Carbohydrate - recommendations for infants have
  been included.
• Fats - recommendations for essential fatty acids
  have been included.
• Water
• Vitamins - biotin, pantothenic acid, choline,
  vitamin K.
• Minerals - chromium, copper, fluoride, iodine,
  manganese, molybdenum, phosphorus.

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Old RDIs vs New NRVs

• Changes have also been made to the recommended
  intakes of some nutrients.
• Recommended intakes have increased for
• thiamine, B6, B12, folate, vitamin A (for men
  only), calcium, zinc (for men only), iron and
  magnesium.
• Recommendations have decreased for
• riboflavin, niacin, vitamin A (for women only),
  zinc (for women only), selenium and sodium
  (salt).

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Old RDIs vs New NRVs

• Vitamin A previously had a recommended daily
  intake (RDI) of 750 mg for men and women aged
  19-54 years.
•  

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Summary of NRVs

• The RDIs, EARs and AIs are set at levels to avoid
  deficiency diseases
• The UL is set to limit harm

Danger of toxicity
Tolerable Upper Intake Level
Marginal
SDT
Safety
RDI or AI
The SDTs aim to prevent or reduce the risk of
chronic disease.
Estimated Average Requirement
Marginal
Danger of deficiency
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Example Long chain Omega-3 (DHA/EPA/DPA) mg/day
NHMRC. Nutrient Reference Values for Australia
and New Zealand. Commonwealth of Australia, 2006.
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How is this information used?

• Ensure nutritional adequacy for therapeutic diets
• eg. low fat diets ? Vitamin A
• a guide for planning menus
• eg. AIS dining room or military

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How is this information used?

• assessment of nutritional adequacy for an
  individual
• eg. your personal dietary analysis
• used in nutrition labelling
• eg. RDI claims on breakfast cereals

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• Sanitarium Fruity Bix
• Serving size 40g (approx. 10 biscuits).
• per serve per 100g
• Energy (kJ) 580 1420
• Protein (g) 3.5 8.8
• Fat (g) 0.6 1.4
• Carbohydrate
• total (g) 29 72
• sugars (g) 7.4 18.6
• Thiamin (mg) 0.55 (50) 1.37
• Riboflavin (mg) 0.42 (25) 1.05
• Niacin (mg) 2.5 (25) 6.2
• Iron (mg) 3.0 (25) 7.5
• RDI (Australia)

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• RDIs for use in Australia (Web link)
• Recommended Dietary Intakes for Australians
• Useful for dietary analysis practical report

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Recommended Reading

• Whitney Rolfes
• Understanding Nutrition, 11th Ed. 2005
• Chapter 1. Nutrition Assessment (section)
• Chapter 2 Planning a Healthy Diet (whole
  chapter)
• Walqvist (Editor)
• Food Nutrition, 2nd Ed. 2002
• Chapter 35. Nutrition Assessment monitoring
  (whole chapter)