A Presentation for Fuengirola by Ian M' Phillips

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A Presentation for Fuengirolaby
Ian M. Phillips
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It's all fairly simple really

• Simple nutrition
• Simple physics
• Simple chemistry
• Simple stupidity

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Do you NEED to lose weight?

• Body-Mass Index BMI Weight (kg)/Height2 (m)?

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Why do we eat?

• To get energy
• To get essential nutrients
• For pleasure

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What is Energy

• Need to distinguish scientific from vernacular
  usage
• Energy is not the same as vitality!
• Lots of different types of energy gravitational,
  heat, potential, chemical, nuclear, mass ...
• Law of Conservation of Energy
• Energy In Energy Out
• For diet and nutrition concerned with heat energy

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Energy

• Measured by calories or joules
• 1 calorie is the amount of heat needed to raise
  1gm of water by 1oC
• Replaced by joule in scientific use
• Food energy uses Calorie (1000 calories)?
• 1 Calorie 4.184 kJ

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Food Energy

• Energy derived from oxidation of
• Fats, Carbohydrates Proteins
• C6H12O6 6O2 6CO2 6H2O Energy
• Energy available as follows
• Protein 1gm gives 4C
• Fat 1gm " 9C
• Carbohydrate 1gm " 4C
• Alcohol 1ml " 7C
• Excess energy intake stored as fat!
• Body fat is 87 lipids

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How much energy do we need?

• It depends on age, sex, activity and size
• Men 18-34 Very Active 3350C
• Men gt75 2150C
• Women 18-54 Very Active 2500C
• Women gt75 1680C
• There is a minimum daily energy requirement
• Basal Metabolic Rate (BMR)?
• Men 70kg 1550C
• Women 55kg 1220C

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Basal Metabolic Rate

• Accurate measurements through gas analysis
• Estimates from different formulae
• The bigger you are the more energy your body
  needs to exist
• Fat people have higher BMRs than thin ones!
• Energy expenditure breakdown
• Liver 27
• Brain 19
• Heart 7
• Kidneys 10
• Muscle 18

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Energy Exercise

• The more active we are the more energy we need
• Exercising boosts BMR and reduces appetite
• Light exercise
• Housework 180 C/hr
• Strolling 150 C/hr
• Moderate exercise
• Walking 200 350 C/hr
• Swimming gt 300 C/hr
• Cycling 200 650 C/hr

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The Exercise Conundrum

• You won't lose weight by exercising, but you'll
  put on weight if you don't exercise.
• Need to look at the long term
• Example
• 225C of exercise 25gm fat
• Over a year (300 days) 7.5 kg
• This is vastly simplified but illustrates the
  point

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Or to put it another way...

• If your energy requirements are 2400 C/day
• and you starve yourself so your intake is ZERO.
• This equates to 300 g/day or 2.1 kg/week (4½lb)?
• and you'll be very ill.

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So where does the energy come from?

• Fundamentally all energy comes from the sun

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Metabolism
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But what do we eat?

• Proteins
• Fats
• Carbohydrates
• Water
• others

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Water

• Essential for life
• Transport
• Solvent
• Temperature Control
• No energy or other dietary value
• Human body is 60-65 water
• In human body of 45 litres
• 27 litres in cells
• 18 extracellular including blood

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More Water

• How much water do we need each day?
• In temperate conditions each day we lose
• 500ml through perspiration
• 500ml in the breath
• 1l in urine
• This water can be replaced by any liquid or food
• In hot conditions or with activity this water
  requirement may be much higher
• Let thirst be your guide

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Carbohydrates

• Chemically simple (sic) starches and sugars
• (CH2O)n
• Require less water to digest than proteins or
  fats and are the most common source of energy
• Not essential nutrients
• 1 g carbohydrate contributes 4 Calories to diet
• However, too low a carbohydrate intake interferes
  with fat digestion
• Breads, pastas, beans, potatoes, bran, rice and
  cereals

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Proteins

• Proteins are complex organic compounds of amino
  acids (NH2CHRCOOH)?
• Human body can make 10 of 20 amino acids
• Proteins are ESSENTIAL in diet
• Require about 1g protein per kg body weight
• Protein deficiency major source of malnutrition
• 1g protein contributes 4 Calories to diet
• Sources of protein have different amino acids
• meats, eggs, grains, legumes, and dairy products

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Fats

• Wide variety of chemical compounds (lipids)?
• Fats solid, oil liquid at room temperature (human
  fat is liquid)?
• Fats may be saturated, unsaturated, trans ...
• Fats are ESSENTIAL in diet
• Source of essential fatty acids
• Necessary for absorption of certain vitamins
• Provide buffer to protect against certain
  diseases
• Primary source of energy in diet (1g gives 9
  Cals)?

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Vitamins Essential Minerals

• 13 vitamins
• 4 fat soluble (A, D, E, K) 9 water soluble (Bs,
  C)?
• Required in very small amounts
• Necessary for life
• Excess can cause disease or side-effects
• Dietary Minerals
• Not minerals but elements
• Macrominerals Ca, Mg, P, K, Na, S (gt 200mg/day)?
• Trace minerals B, Cr, Co, Cu, F, I, Mn, Mo, Se,
  Si, V, Zn (lt200mg/day)?
• Wide range of disease due to lack or excess

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Vitamin Requirements
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Dangers of Excess - Vitamins

• Fat soluble vitamins (A, D, E K) are stored in
  the body and excessive intake is dangerous
• A nausea, jaundice, weight loss, death
• D hypercalcaemia, renal failure
• E increased risk of mortality
• Water soluble vitamins (B, C) are not stored and
  need to be regularly replenished but there may be
  toxic effects from excessive intake

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Dangers of Excess - Minerals

• Iron Liver heart damage, effects zinc intake
• Zinc Suppresses iron and copper absorption
• Calcium Kidney stones
• Iodine Thyroid problems (similar to I deficiency)?

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But we don't eat proteins and carbohydrates and
fats.We eat food (more or less).So ...
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What's in it for me?
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The Worldwide Variety of Diets

• Inuit
• Seal meat, raw blubber, seal blood soup, boiled
  and raw fish
• Sami
• Reindeer meat, some fish and wild berries with
  low intakes of other fruits, vegetables and dairy
  products
• Mongolian
• Meat (sheep camel), milk, flour, wild onions
  garlic
• Australian Aborigine
• Mostly raw including reptiles, insects, grubs
• Traditional Zen Monks
• Rice, fermented soya beans, pickles, vegetables
  (not onions), green tea

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Chemicals Additives

• H2O
• NaCl
• C17H23NO3
• C17H20N4O6
• C39H54N10O14S
• C11H26NO2PS
• C2H5OH
• CH3OH

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Chemicals Additives

• H2O - Water
• NaCl - Common salt
• C17H23NO3 - Atropine
• C17H20N4O6 - Riboflavin
• C39H54N10O14S - Amanitin
• C11H26NO2PS - VX
• C2H5OH - Ethyl alcohol
• CH3OH - Methyl alcohol

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Chemicals Additives

• If someone came into your house and offered you a
  cocktail of butanol, iso amyl alcohol, hexanol,
  phenyl ethanol, tannin, benzyl alcohol, caffeine,
  geraniol, quercetin, 3-galloyl epicatchin,
  3-galloyl epigallocatchin and inorganic salts,
  would you take it?

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Chemicals Additives

• If someone came into your house and offered you a
  cocktail of butanol, iso amyl alcohol, hexanol,
  phenyl ethanol, tannin, benzyl alcohol, caffeine,
  geraniol, quercetin, 3-galloyl epicatchin,
  3-galloyl epigallocatchin and inorganic salts,
  would you take it?
• If instead you were offered a cup of tea, you
  would probably take it.

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E Number TestWhich of the following are E
numbers

• Riboflavin
• Formic Acid
• Fluorine
• Monosodium Glutamate
• Sulfuric Acid

• Cochineal
• Sugar (fructose)?
• Lecithin
• Chlorophyll
• Helium

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E Number TestWhich of the following are E
numbers

• Riboflavin
• Formic Acid
• Fluorine
• Monosodium Glutamate
• Sulfuric Acid

• Cochineal
• Sugar (fructose)?
• Lecithin
• Chlorophyll
• Helium

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E Numbers

• European subset of International Numbering System
  determined by Codex Alimentarius
• Codex Alimentarius is a collection of
  internationally recognized standards, codes of
  practice, guidelines and other recommendations
  relating to foods, food production and food
  safety under the aegis of consumer protection ...
  established in 1963 by the Food and Agriculture
  Organization of the United Nations (FAO), and the
  World Health Organization (WHO)?

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E NumbersMore than you really want to know

• Classification by numeric range
• E100E199 (colours)
• E200E299 (preservatives)
• E300E399 (antioxidants, acidity regulators)
• E400E499 (thickeners, stabilizers, emulsifiers)
• E500E599 (acidity regulators, anti-caking
  agents)
• E600E699 (flavour enhancers)
• E900E999 (miscellaneous)
• E1000E1999 (additional chemicals)
• Sub-division examples
• E100-109 Yellows
• E320-329 Lactates
• E410-419 Natural Gums

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E Numbers

• Some examples
• E102 Riboflavin (Vitamin B2) Yellow colouring
• E300 Ascorbic Acid (Vitamin C) Anti-oxidant
• E336 Cream of Tartar
• E407 Carrageenan Thickener, emulsifier
• E621 Monosodium Glutamate Flavour enhancer
• You may need to be aware of concentration

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What is an E-number? Since 1986, food additives
colours, preservatives, antioxidants,
stabilisers, gelling agents, thickeners, etc.
have been identified in food labels, either by
name or by E-number. An E-number says that it has
been approved for its intended use across the
European Union. Approval depends on scientific
testing and monitoring and is reviewed in the
light of new scientific information. Additives
have been around for centuries. Nitrites and
nitrates (E249-252) have been used as curing
agents. Baking powder (bicarbonate of soda
sodium hydrogen carbonate, cream of tartar
potassium hydrogen tartrate, monopotassium
tartrate, E336 and starch) is a 19th century
additive. Pickling is an ancient method of
preservation that uses vinegar (acetic acid,
E260) to prevent microbial spoilage. Many agents
that are essential for commercial food
preparation and storage have their analogues in
the kitchen. Caramel (E150a), a colouring agent,
can be made at home by heating sugar. Gelling
agents include pectin (methylated ester of
galacturonic acid, E440) for jams. Preservatives
include benzoic acid (E210), present in high
quantities in cranberries. Some additives are
clearly beneficial in 1941 calcium was added to
flour to prevent rickets and anti-oxidants
(necessary to prevent the fats in all prepared
foods involving meat or pastry from going rancid)
include ascorbic acid (vitamin C, E300) and the
tocopherols (vitamin E, E306-309). Paul Illing,
toxicologist
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Anti-Oxidants Free Radicals

• The metabolism paradox
• Oxygen is essential for life
• Oxygen causes damage to cells by producing free
  radicals (amongst others)?
• A (free) radical is an atom or molecule with an
  unpaired electron. They are highly reactive.
  Their reactivity may cause damage to living
  cells.
• So we take anti-oxidants to reduce the damage
• Don't we?

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Anti-Oxidants Free Radicals

• Anti-oxidants include Vitamins C E, Uric Acid,
  Carotenes, Melatonin ...
• However! Beware of redox recycling
• Evidence of the benefits of anti-oxidants is
  still being gathered
• Excessive use of anti-oxidants may have adverse
  health effects in the elderly.

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Anti-Oxidants Free Radicals
CONCLUSION We did not find convincing evidence
that antioxidant supplements have beneficial
effects on mortality. Even more, beta carotene,
vitamin A, and vitamin E seem to increase the
risk of death. Further randomized trials are
needed to establish the effects of vitamin C and
selenium.
(Reprinted) JAMA, February 28, 2007Vol 297, No. 8
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Pre-, Pro- or Anti- Biotics?

• Gut flora are the micro-organisms that live in
  the digestive tract and perform a number of
  useful functions
• Acquired post-partum (babies digestive tracts are
  sterile) in 2years
• Bifidobacterium (Lactobacillus Bifidus) is one of
  many types
• Helpful bacteria may be harmful if outside the
  gut
• Do you need more of them?

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Pre-, Pro- or Anti- Biotics?

• Probiotics are dietary supplements
• No published evidence that probiotics can
  supplement body's natural flora when these have
  been killed off.
• "I'm not entirely sure there is any great benefit
  in young healthy people. On the other hand they
  may not do any harm."
• ...some products being marketed as probiotics
  had no demonstrated probiotic properties
  whatsoever.
• "Some actually contain bacteria that are harmful.
  People have to be very careful if they are buying
  these things over the internet or even from a
  health food store."
• Professor George MacFarlane, professor of
  bacteriology at the University of Dundee

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Pre-, Pro- or Anti- Biotics?

• Prebiotics are food
• 'Non-digestible food ingredients that
  beneficially affect the host by selectively
  stimulating the growth and/or activity of one or
  a limited number of bacteria in the colon, and
  thus improve host health'
• Dietary sources are
• Soy beans, raw oats, unrefined wheat barley,
  inulin (chicory, garlic, leek)?

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Allergies Food Intolerance

• An allergy is a response, within the body, to a
  substance, which is not necessarily harmful in
  itself, but results in an immune response and a
  reaction that causes symptoms and disease
• Intolerance happens when unpleasant symptoms
  occur after eating a substance which your body
  cannot handle because the digestive system does
  not produce sufficient quantities of a particular
  enzyme/chemical, which is needed to break down
  the food and aid digestion.

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Food Intolerance

• Common food intolerances are
• Lactose (milk etc)?
• Alcohol
• Gluten (coeliac disease)?

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Lactose Intolerance
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Celebrity Misconceptions - 1
Jamie Oliver chef on the benefits of organic
food I want to cook with the best ingredients
and have food the way it should be healthy,
tasty and grown with nature.
Prof. Vivian Moses Biologist, Kings College
London Jamie, we all like healthy and tasty, but
what do you mean by grown with nature? Not one
of our crop plants or domestic animals exists in
the wild they have all been created by selective
breeding over the past 10,000 years. Wheat, for
example, doesnt exist in nature we made it. And
nowhere on earth do crop plants exist in rows
unless we put them there.
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Celebrity Misconceptions - 2
Gillian McKeith television presenter on the
nutritional benefits of eating seeds each
sprouting seed is packed with the nutritional
energy needed to create a full grown healthy
plant. Dr Steve Rawsthorne Plant Scientist,
John Innes Centre This is a nice idea Gillian,
but when we eat seeds we dont break down the
stored products like a plant does, so we do not
get the same balance of energy and nutritional
components that the plant benefits from. A seed
has stored proteins, starch and oil that are
broken down when water is added to give it the
energy and molecular building blocks to start the
germination process and grow into a seedling. To
become a fully formed plant the seedling then
needs sunlight and more water.
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Celebrity Misconceptions - 3
Heather Mills McCartney former model every
day theres a new report warning that obesity
levels in children are out of control... The fact
that those kids who drink the most milk gain the
most weight should cause alarm bells to be
ringing everywhere. It isnt and milk is still
being pushed as essential for children.
Dr Philip Coan Physiologist, University of
Cambridge It is not true to say that children who
gain the most weight are doing so because of milk
consumption. A US study looked at drink
consumption in 2-5 year olds over a three year
period.1 It found no link between increases in
child weight and increases in drink consumption.
In relation to milk, child weight was not linked
to whether the children drank full fat,
semi-skimmed or skimmed milk. Dr Joanne Lunn
Nutritionist, British Nutrition Foundation Milk
is one of the most nutritionally complete foods
and if people excluded milk and dairy products
from their lives, they would miss out on many of
the most important constituents of a healthy diet.