Health and Social - Carbohydrates, Proteins and Fats

Carbohydrates (also called saccharides) are molecular compounds made from just three elements: carbon, hydrogen and oxygen.

Monosaccharides (e.g. glucose) and disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars. Which include glucose, fructose and galactose, or double sugars (disaccharides), which include sucrose (table sugar Glucose + Fructose), lactose (Glucose + Galactose) and maltose (Glucose + Glucose).

Sugars

• Chocolate
• Honey
• Syrup
• Jam
• Cakes
• Biscuits
• Puddings
• Apricots

Complex carbohydrates, also known as polysaccharides, are starches formed by longer saccharide chains, which means they take longer to break down.

The properties of starch are very different from that of glucose. They are not water soluble and requrie being chemically altered (i.e being broken down by cooking) to allow them to be digested.

Starches

• Bread
• Potatoes
• Cereals
• Rice
• Pasta

NSPs - Non-Starch Polysaccharides

• Bran Products
• Wholemeal Bread
• Peas
• Beans
• Sweetcorn

Include substances such as fibre, these are insoulble and can not be broken down by digestion. They pass through the body chemically unchanged. The main one of these is cellulose the one that gives plants structural strength.

Some are insoluble and cannot be broken down by digestion.

How are carbohydrates utilised?

• Eaten
• Digested
• Glucose can then enter into the blood stream
• If glucose is not needed, it is stored as glycogen which are long chains of glucose molecules
• Long chains of glucose molecules stored in the muscle and liver
• When needed the glucose will combine with oxygen to make energy

Function:

• Energy supply to the body
• Starch is digested and stored as glycogen
• Sugars and Starches are most efficient
• Fats contain more energy but require more O2 to break down

Proteins

Proteins are made from long chain of smaller molecules called amino acids. Amino Acids are monomers, the protein is the polymer. These long chains are folded into particular shapes. This is important in relation to how proteins work.

• Provide the chemicals to make the body grow
• Provides all the chemicals to help the body repair the damage after illness, accidents and surgery
• It maintains the body to keep working well - producing enzymes (control all the chemical reactions within the body) for digestion, muscle activity, nerve function and hormones

Secondary Source of Energy

Meat, Fish, Cheese, Eggs, Nuts, Quorn are good sources of protein

Protein Function:

• Hormones (such as insulin)
• Antibodies (part of the body's immune system)
• Biological Catalysts (Enzymes)
• Structural components of tissues (such as muscles)

Amino Acids

Essential:

• Can not be made by our bodies
• Must eat the protein that contains them
• There are 9 of these needed
• Food which contains all of the essential amino acids are called HBV proteins (high biological value proteins)
• Food which contain some of the essential amino acids are called LBV proteins

Non-Essential:

• Can be made by our bodies from the protein we eat
• 11 of these

Protein mainly come from meat but there other foods rich in protein.

Veggies eat proteins extracted from soya beans and fungi

HBV

• Meat
• Egg
• Cheese
• Fish
• Milk
• Soya

LBV

• Cereals
• Rice, Wheat and Oats
• Pulses, Lentils and Beans

Too Much or Too Little Protein

Too Little

Children:

• Slow growth/Loss Weight
• Thin hair/loss
• Change in skin colour
• Can't digest food 
• Low energy/weak/catch infeections
• Build up of fluid under skin - OEDEMA

Adult:

• Loose fat and muscle/weight loss
• Fluid build up - OEDEMA
• Cuts and bruises slow to heal/ catch infections
• Lack of energy
• Dry hair and skin

Protein Deficiency

Kwashiorkor 

A type of proetin energy malnutrition.

Who is at risk?

Infants and children in underdeveloped countries

Those around the world who live in extreme poverty

The eldery who live by themselves, low protein diet

Macronutrients can also be called Lipids

Fats are important as:

• Concentrated source of energy
• Form structure of some cells membrane (brain)
• Is stored under the skin to help insulate the body (preserve heat)
• Vital organs such as the liver and kidneys are protected by a layer of fat
• Source of fat-soluble vitamin A,D, E & K

Fats are made up of the elements = carbon, oxygen and hydrogen these elements make up molecules of glycerol and fatty acids

When digested they can be broken down into fats in the bloodstream and glycerol to the liver

There are at least 40 different fatty acids and these can be either SATURATED OR UNSATURATED, according to the way their carbon & hydrogen atoms are arranged.

Saturated Fatty Acids:

• All carbon atoms are saturated with hydrogen atoms
• Tend to be Solid at room temperature
• Mostly animals
• Rises blood cholesterol increasing the chance of heart disease

Unsaturated Fatty Acids:

• Some of the carbon atoms are joined by double bonds – so are not completely saturated with hydrogen
• Two types of unsaturated fat.

Monounsaturated Fatty Acids

• There is a link in the carbon chain that has a double bond
• Found in olive oil and soft margerine
• Helps build cell membranes

Trans Fat

• Manufacturers can use a process called HYDROGENATION - unsaturated fat usually veg oil gets partly saturated with Hydrogen
• Bonds change position
• Purpose is ti make liquid into solid i.e. Margarine from sunflower oil

Fat or Fatty Acid 

• People use the terms 'fats' and 'fatty acids' as if they are the same
• It is actually the fatty acid that is saturated or unsaturated 
• Fats mostly always contain a mixture of saturated, monounsaturated and polysaturated fat acids.

Animals 

• Meat and meat product
• Dairy products e.g. milk, cheese, butter and cream
• Fish oil fish like tuna, sardines and salmon

Plants

• Avocadoes
• Olives
• Nuts and Pulses, e.g peanuts walnuts
• Seeds e.g. Sesame, sunflower and soya

Essential Fatty Acids (EFAs)

• There are fatty acids that can not be made by the body, but are needed to function efficiently
• Regulating body processes such as blood clotting and control of inflammation
• Omega 3 - oil fish, seeds and leafy green veg - protects heart
• Omega 6 - veg, fruits, grains, chicken and seeds - lowers cholestrol

Where can we find fat?

• Cooking oil
• Butter
• Margarine 
• Lard
• Bacon
• Salami
• Cheese
• Cream 

Too much or Too little

Too much as fat is a high energy wource if we do not use up the fat we consume it gets stored and the body will gain weight

Too little - it is essential for growth, so babies and children will not grow and become thinner and feel the cold more