Individual lifestyle determins risk of disease
Advise people to change own behaviour
Effective if disease related to behaviour
Fail if individual not motivated
Fail if cause outside of individuals control
Risk of disease determined by culture/society
Aims to shape society to better suit health
Effective if dealing with long term/global issues
Fail if aims too bold!
Public Health Nutrition
Promotion of good health through prevention of nutrition-related illness
Design of nutritional interventions in the population
Apply knowledge to solve nutrient-related problems
Identify causal pathways and means of prevention
Results from poor access to food and follows disease
Limited access to health sevices
Poor food hygiene
Lack of clean water
These are all a result of politics, lack of money and lack of education
"The study of the distribution and determinants of health-related states or events in specified populations, and the applications of this study to control health problems."
Main source of information for PHN
Identifies nature of problems
Allows monitoring of success if action taken
Relationship between exposure and outcome (simple or complex)
Process of enabling individuals of communities to increase control over factors that determine their health:
Healthy Public Policies
Developing personal skills of public and professionals
Changing behaviour through:
Recommendation and guidance
Fortification and Supplementation
Fortification - Ensures all consumers have a good intake
Takes away choice
Supplementation - Requires education
Successes in PHN
Rickets - Only identified as dietary disorder in 1916. Gave cod-liver oil to children on poor diets effective. Margerine now fortified wtih Vit D. Vit D also added to some cereals and other spreads.
Water Flouridation - gum disease
Development of dietary guidlines and DRV
Improvments in food labelling
DEFRA - Labelling and legislation
FSA - Safety based labelling and standards
DoH - Nutrition policy labelling
FSA - All domestic labelling and standards and legislation
FSA - Labelling
Welsh Assembly Government - Nutrition legislation
Pre-packaged foods labels
Basic labelling must include:
List of Ingredients
Address of manufacturer (Name of business)
Appropriate date mark
Place of origin or provenance of food
Storage and prepartion instructions
Weight and Volume of food
Name of the food
New food labelling legislation
All packs with area >10cm2 require nutritional information
Must include energy, protein, carbohydrate, fat (sat fats, sugars, fibre, salt will replace sodium)
If ingredient is mentioned in name of product, % must be included
Compound ingredient ingredients must be included
14 allergens must be included
Gluten Crustations Fish
Celery Eggs Lupin
Milk Molluscs Nuts
Mustard Peanuts Sesame
Soya Sulphates > 10ppm
Full nutritional information must be provided on the pack if a claim is made
Content claims can only be made if on the list in the Annex to regulation 1924/2006
No nutritional claims may be made for macronutrients with levels <15% RDA per serving
Comparitive claims only made between foods of same category
European Commission will develop 'Nutrient Profiles' with regard to levels of saturated fat, sugar and sodium. Meeting this profile is a condition of making a health/nutrient claim
Changes to legislation
Mandatory Nutrition information
Minimum font size
Date of first freezing for meats and fish
New definition of 'use by'
Country of origin/provenance
Allergens must be emphasised
"Live microorganisms that when administered in adequate amounts will confer a health benefit on the host (surviving passage through the stomach)"
Newborn has sterile GIT. Innoculated with bacteria during birth and breast feeding (colostrum)
Coats the bowel
Protect from pathogens
Good intestinal health = 85% good microbes 15% bad microbes
Gut microflora affected by hospitalisation, feeding, antibiotic use
Effective probiotic must be
Remain viable through storage and use
Exert one or more beneficial effect on health
Most strains are Lactic Acid Bacteria (LAB)
Sources include fermented food or specific probiotic prepared food
Probiotic Health Benefits
1) Regulate balance of gut microflora by decreasing pathogen adhesion as they produce antimicrobial substances
2) Improve digestion of lactose by producing Beta-Galactosidase and enhancing absorption of sugars
3) Stimulate the immune system by up-regulating (Gut-associated lymphoid tissues (GALT) are the largest intrinsic protection against infective agents)
4) Other health benefits include lowering serum cholesterol levels and promoting anticarciongenic effects
"Non-digestible food ingredients that beneficially affect the host by selectivly stimulating the growth and/or activity of one or a limited number of bacteria in the colon"
Reaches the colon intact
Specific metabolism directed towards advantageous rather than adverse bacteria
Active at nutritionally feasible dose
Lack of side effects
Persistent throughout the colon
Oligosaccharides have the best prebiotic effect.
Typically found in plants, seeds and tubers (also in colostrum)
Benefits similar to probiotics and increases production of SCFAs
Improves mineral absorption and balance
"A food component which affects one or more targeted functions in the body in a positive way"
Established foods which have been shown to provide specific benefits
Targetted at any disease state:
Reduce cholesterol as part of a low fat diet
Rich in soluable fibre
Soluable fibre binds bile acids increasing excretion while decreasing cholesterol absorption
Part of a healthy diet
High in essential polyunsaturated fats and low in saturates
No hydrogenated oils, virtually no trans fatty acids (animals ones are fine) and rich in Vit E.
Contains plant stanol ester
Unique dietary ingredient derived from natural plant components (veg oil, beans, wood)
Added to food stuffs such as yoghurt
Displaces cholesterol in micelles so most cholesterol is excreted and stanol ester is absorbed in the gut
Proctor & Gambles brand name for Olestra
Sucrose polyester and is a non-absorbable fat
It has physical and organleptic quantities of conventional dietary fats
Reduces fat and energy intake as it replaces triacylglycerol with sucrose polyester
US FDA approved Olestra for use in fried/baked snack foods
Absorption of Vit D, A, E & K can be reduced if consumed with Olean.
Those 4 Vits added to foods to offset impact
"A mix of the words 'Nutrients' and 'Pharmaceuticals' to indicate a food component/nutrient which has drug-like effects on physiological functions"
Consumption of fruit/veg negativly correlates with several chronic diseases.
Green tea (reduces blood pressure), cocoa, pomegranate juice (reduces BP, LDL oxidation), red wine and liquorice (reduces blood pressure) are associated with health benefits
Resvertrol = Stilbene. Found in 72 plant species
Absorbance - 70%
Inhibits platelet aggregation
Regualates cell signalling and gene expression
Global Food Security
Food choices of population
Ability of ecosystem to sustain food production
United Nations Millennium Development Goals (Aim to acheive by 2015)
Goal 1 = Eradicate extreme poverty and hunger
Agriculture accounts for 75% fresh water withdrawal as well as a heave carbon footprint. Ruminants also produce a lot of methane
Conversion of plant into animal matter is around 10%. Solutions include fish farming, quorn or edible insects
Basic Principles of Equine Nutrition
Hind Gut fermenters - large colon
Trickle feeds, continually grazing so small stomach. 16-18hrs low quality grazing
Cutting action with 12 insicors, 24 molars to grind. Hypsodont dentition
Owner kept in mind
Is it a working animal?
Ability to perform/produce
Usually feed the individual needs
Equine Gastric Ulcer Syndrome - EGUS = 90% racehorses in training
Stomach is empty but HCl production continuous
Concurrent decrease in fibre, increase in starch/energy rich feeds
Entirely preventable and reversible but incredibly painful
Basic principles of Canine Nutrition
Rely on stomach to digest proteins. They are omnivorous meal feeders.
They have canines and sharpe molars to rip and chew. (Limited side to side motion)
Adapt easily to high levels of starch and can consume 10g/kgBW without side effects
Fibre fermention is low, and water is absorbed in the colon.
Diet designed with owner in mind
Healthly looking animal/nice coat
Ease of feeding
Feeding the individual
Basic Principles of Feline nutrition
Rely on stomach to digest proteins
Strict carnivores with 12-20 meals a day (high quality foodstuff)
Exibit lowers activity of the brush border enzymes
Fibre fermentation is low, and water is absorbed from the colon.
Caecum much smaller than dogs
Diet designed with owner in mind
Looking healthy/Coat condition
Ease of feeding
Basic Principles of Animal Nutrition
Natural eating behaviour is related to anatomy and physiology
Duodenum is the first stage of the SI. Bicarbonate (buffer) is there to neutralise stomach acid while pancreatic enzymes are also released.
Requirements are for Energy, Protein, Vitamins, Minerals
When choosing ingrients you must consider natural feeding behaviour
Cats arn't vegetarians because they cannot synthesise taurine which only comes from meat
They also cannot synthesise Vit A
Or convert Tryptophan to Niacin
Dogs Cannot synthesise Vit D
Obesity is a bit problem when diets are wrong!
Carnivores = concentrated diet, easily digested
Omnivores = intermediate feeding system
Herbivores = poorly digested fibrous diet (use of microbes)
Types of digestive systems include;
Grasping the food
Saliva is secreted from 4 major pairs of glands and then chewing helps break down the food
1) Parotid = watery secretion
2) Mandibular = watery and mucus secretion
3) Sublingual = mucus secretion
4) Zygomatic = Viscous mucus secretion
Skull shape and dentition are linked to diet
Cattle and sheep have a horny pad instead of teeth in the upper front jaw
Dogs have carnassials (cats don't)
Tube connecting mouth to the stomach.
Peristalsis occurs to move the food down towards the stomach
Birds have a crop to store food. They swallow food whole and mucus is secreted in the crop
Food store and gastic juices are secreted.
Contractions help mix the secretions with the contents and break down the food
Avian digestive tract has 2 stomachs. Glandular stomach (proventriculus) secretes mucus, HCl and pepsin. The muscular stomach (gizzard) may contain stones for grinding. Feed is forced back and forth between the two. Regurgitation also occurs in some species.
Liver and SI
Liver = largest organ with lots of functions
Produces bile salts and nutralises chyme
Small Intestine = Duodenum, jejunum, ileum
Secretes intestinal juices which contain enzymes
Mucin is also produced to protect the intestinal walls from the acidic chyme.
Pancreas and LI
Pancreas = secretes pancreatic juice into the small intestine.
Juice contains trypsin, lipase and amylase to digest proteins, fats and starch respectivly. This is alkaline to neutralise stomach acid
Large Intestine = Caecum, colon, rectum
Bacterial fermentation occurs and water and ions are reabsorbed.
Faeces is formed here but defication is controlled by the anal sphincter
A large, anaerobic fermentation vat, containing microorganisms which ferment fibre to make: Volatile Fatty Acids (VFA’s) Microbial protein Vitamins K and B-complex. The rumen wall is lined with millions of papillae (short projections) which increase the surface area for absorption of VFAs. Shag-pile carpet” appearance In constant motion with1-3 contractions per minute. Filled with liquid, fibre mat & gas. Contractions: mix contents and aid in eructation of gases move fluid and fermented feedstuffs onto next stage Move fibrous materials into the fibre mat for rumination
Provides additional fermentative capacity An extension of the rumen rather than a separate chamber Larger food particles from the rumen are returned to the mouth to be chewed again. Small food particles from the rumen are passed into the omasum. Honey comb lining catches and holds hardware and heavy debris Rumen magnet to remove metal
A heavy, hard organ Lining has many folds (leaves). Water and residual VFAs and bicarbonate are absorbed here. Contents in this compartment are much drier than elsewhere.
The true, glandular stomach. Secretes hydrochloric acid and digestive enzymes and functions very much like the monogastric stomach. Unique feature is that it secretes lysozyme. Enzyme that can break down bacterial cell walls.
A.k.a. “chewing the cud” Bolus of previously eaten foodstuff carried back from the reticulum to the mouth by reverse peristalsis, chewed and re-swallowed. ~8-10hrs per day, dependant on how fibrous the ingested material is. The cud can be chewed at least 30 times (ideally 60) before re-swallowing.
Usually occurs when cows are resting - 4 Phases;
Regurgitation - coarse material the upper end of the rumen stimulates a bolus of feed (cud) to be returned to the mouth. Chewing - each cud is chewed to grind it down into particles small enough to pass out of the rumen. Salivation - chewing stimulates the secretion of buffer-containing saliva (as much as 75 litres/day) which is mixed with the cud to stabilise rumen pH. Swallowing – once sufficiently ground down the cud is swallowed and sinks to the bottom of the rumen to pass into the reticulum.