Richard Trim Malcolm Ballantine. Halesworth & District

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1 Richard Trim Malcolm Ballantine Halesworth & District

2 Setting the Scene Public Health England established 2013 Healthcare vs Health Healthcare responsibility of NHS Health responsibility of PHE Healthcare: Diagnosis and treatment of illness etc Health: Creating the conditions in which people can lead healthy lives for as long as possible.

3 PHE Role

4 Premature Death

5 Behavioural Patterns Eat a balanced diet Take more exercise Don t smoke Drink alcohol in moderation

6 What is Health? Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity. Constitution of the World Health Organisation

7 Food: An overview Putting things in perspective Life style influences on eating habits Eating for pleasure or health 21st century food issues The focus: salt, fat, sugar

8 Basic Science Two Issues It s complicated and becoming more so... It s difficult to communicate to the public

9 Basic Science 1950s Four categories of foodstuffs: Protein Carbohydrates sugars and starches Fats Vitamins (Malcolm, O-level Biology, 1957)

10 Basic Science 1960s It s more complicated... eg Cholesterol may have negative effects on arteries but is essential for health broken down on entering the digestive system created within the body Dietary Fibre is important yet has no nutritional value There are important interaction effects (eg free fructose is unhealthy but OK bound with fibre ie in fruit) (Malcolm, BSc Physiology Course, 1969)

11 Communicating 2011

12 Communicating 2016

13 Salt So what s the problem? Why is salt so bad? Where is our salt coming from? So what s being done?

14 Some (very) basic organic chemistry Carbon atoms, together with atoms of other elements, in particular hydrogen and oxygen, can link together to form long chains These compounds form the basis for life they are organic The links between the atoms are known as bonds Carbon has four available bonds, oxygen two and hydrogen one

15 A Simple Hydrocarbon - Methane

16 and with two carbon atoms - Ethane

17 and eight - Octane

18 Here, there is a double bond

19 and here, a carboxylic group Propionic Acid to yield a carboxylic acid

20 Fatty acids and glycerol Longer chain carboxylic acids are known as fatty acids This is because they can combine, in threes, with glycerol (which is an alcohol) The result is a triglyceride The common name for triglycerides is FAT

21 Double bonds in the chain If the bonds between the carbon atoms in a chain are all single bonds, this makes possible the maximum number of hydrogen atoms Such a chain is said to be saturated If there is one or more double bond in the chain, the number of hydrogen atoms will be less than the maximum possible Such a chain is said to be unsaturated

22 Double bonds and fats Fats with only single bonds in the chain are known as saturated fats Fats with just one double bond are known as monounsaturated fats Fats with multiple double bonds are known as polyunsaturated

23 The position of the first double bond In an unsaturated fat, the first double bond from the carboxylic end can be at the third or sixth carbon atom The end of the chain nearest the glycerol is known as the alpha end, the end of the chain to which the carboxylic group is attached is the omega end If the first double bond is at the third carbon atom in the chain, the fat is known as an omega-3 unsaturated fat. Likewise, if the first double bond is at the sixth carbon atom, the fat is known as omega-6

24 Examples of sources of fat Saturated Fats Animal fats eg meat, butter, whole milk; coconut oil; palm oil Mono-unsaturated fats Olive oil, sunflower oil, avocados Poly-unsaturated fats Omega-3 Flax, hemp, soybean oil, beans, eggs, sardines, oily fish eg sardines, herrings, mackerel, salmon Omega-6 Poultry, nuts, most other vegetable oils

25 Functions of Fats Source of energy much higher energy density than carbohydrates but slower release time Thermal insulation helps maintain core temperature Needed to build cell membranes Transport for fat-soluble vitamins (A, D, E & K) Fat is essential for good health

26 Is Saturated Fat Bad for You? Until recently, a cornerstone of dietary policy has been based on the assumption that saturated fat raises low density lipoprotein levels which increases deposits of cholesterol in the arteries While this is true, it is now known that it also increases high density lipoprotein levels which reduces the risk Overall, the effect on cardiovascular disease appears to be neutral there is no experimental evidence to show saturated fat is bad

27 Omega 3 vs Omega 6 We depend on derivatives from both omega-3 and omega-6 fatty acids for cell growth In our evolutionary past the consumed ratio of omega-3 to omega-6 fats was about 1:1 Today, the diet of the Inuit population consumes omega-3 to omega-6 in the ratio of about 1:4 In the average Western diet the ratio is about 1:16 Since omega-3 and omega-6 fats compete for the same conversion enzymes, the result is a reduced ability to produce the necessary omega-3 derivatives

28 Trans Fats Artificially produced by hydrogenating monounsaturated oils hydrogen added to oil under high pressure and temperature The resulting fat is (1) solid rather than liquid and (2) has a long shelf life When consumed it increases the level of low density lipoproteins and decreases the level of high density lipoprotein. This increases deposits of cholesterol in the arteries.

29 Sugars What is sugar? Familiar terms for sugar... Sucrose Dextrose Fructose Maltose Lactose Does sugar alone make you fat?

30 Energy Content per Gram Fat Protein Carbohydrate Sugar Alcohol 38kJ 17kJ 17kJ 17kJ 30kJ

31 The Myths or not of Sugar Sugar and Concentration Is Sugar Addictive? Sugar and Type 2 Diabetes

32 Function of Sugars Source of energy much lower energy density than fats but much faster release time

33 Sugars and Fats Much dispute on the relative health effects of sugars and fats Too much of either is not good Trans fats are to be avoided Recent research has revealed that sugar plus fat is problematic The ratio is crucial 50:50 has the maximum negative impact and is only found in processed food This is the ratio in ice cream; cheesecake; doughnuts

34 Sugars and Fats The mechanism appears to be in one sense simple: a fat/sugar mix in this proportion removes the natural tendency to stop eating when you have had enough In another sense it is complex: the fat/sugar mix interferes with nicotinic acetylcholine receptors (nachrs) in the brain. At this level of analysis, the neurological effect can be seen to be very similar to the effects of tobacco and hard drugs As a result, smoking, drug addiction and obesity are being researched as similar behavioural problems

35 Practical Implications Until we know more Eat a balanced diet Increase the ratio of omega-3 to omega-6 unsaturated fats Avoid processed food especially those containing trans fats and a 50:50 sugar/fat mix Exercise to avoid loss of muscle mass

Biochemistry. Definition-

Biochemistry. Definition- Biochemistry Notes Biochemistry Definition- the scientific study of the chemical composition of living matter AND of the chemical processes that go on in living organisms. Biochemistry Facts 1. The human