Function: Maintain, grow and repair, muscle tissue, nails, hair, enzymes and antibodies. There are 9 essential amino acids and 12 non essential amino acids. We can produce these non esseential amino acids through our body processes but we can't produce the essential amino acids so we gain them by our diet.
Sources: There are two types of protein, High biological value and low biological value(LBV). High biological value(HBV) proteins contain all of the essential amino acids whereas low biological value proteins do not contain all amino acids required. HBV proteins are usually found in animal products such as meat, dairy, poultry and soya beans(the only vegan HBV protein). LBV proteins are usually found in plant products in chickpeas, beans, mycoprotein(mushroom fungus and eggwhite(or potato starch)), Tofu(curdled soya milk), TVP(Textured vegetable protein made from soya beans and flour). Different LBV proteins can be mixed to gain all essential amino acids and this is called protein complementation.
Daily Requirement: 55g of protein is required for men and 45g of protein is required for women. Pregnant women require 6g more protein, growing children need more protein(relative to size and mass) and physically active people need more protein for muscle growth and repair.
Excess of protein: Extreme liver and kidney stress as they help process these proteins.
Deficiency: This can cause slowed growth in places such as hair, nails and skin and can cause wounds not to heal fast. The immune system does not function properly as well so there is a higher risk of infection. If this becomes a severe malnutrition, you can develop kwashiokor or odema(build up of fluid in feet or in severe cases, swelled up bellies).

Function:To provide energy. Carbohydrates are split into 2 categories, simple(sugar) & complex(starch). Starchy foods contain lots of nutrients such as fibre, b vitamins, Iron and Calcium. Sugars don't have any other nutritional benefit but bursts of energy.

Chemistary of Carbohydrates: Simple carbohydrates are either monosaccharides or disacchardies. A monosaccharide is a single sugar molecule/monomer and can include galactose, fructose and glucose. These can be bonded by condensation reactions forming glycosidic bonds which can either be beta or alpha. beta bonds can't be broken by our digestive system unlike alpha bonds. These monosaccharides can be joined into ogligosaccharides(3-10 monosaccharides) or polysaccharides(>10 monosaccharides) which are complex carbohydrates. Polysaccharides are always broken down into their monosaccharide form so the more molecules, more of a steady release the food will give but monosaccharides are easily digested as they have no bonds causing it to be a sugar. Monosaccharides and disaccharides contain fewer bonds as there are only 1-2 bonds connecting the molecules so they have a high glycaemic index. This is due to the fact that they can be digested very quickly so it's index is high. Polysaccharides contain more bonds so it takes more time to digest causing it to have a low glycaemic index.

Sources Half of your body should be carbohydrates(minority should be sugars. Simple carbohydrates is found in sugary products or food that contains sugar such as sweets, honey, fruits and cakes. Complex carbohydrates is found in starch such as bread, cereal, pasta, potatoes and rice.

Deficiency This can cause hunger, dizziness and tiredness due tot the fact that your blood sugar level as dropped. This also make you lose muscle making you weaker as your body will use protein as energy. You can also lose fat as your body will use this up causing weight loss.

Excess: This can cause obesity and maybe type 2 diabetes. type 2 diabetes would occur due to fact that too much sugar can fluctuate your blood sugar levels which can make you stop producing insulin leading to Furthermore, more sugar can cause tooth decay as sugars rot your teeth. Too much carbs can lead can lead to fats being stored after too much.

Fuction:To provide insulation layer to heat and protect the body as well as fat soluble vitamins(A, D, E, K) and provides more concentrated source of energy.

Chemistary of Fats: Fats are made up of fatty acids and glycerol in the form of triglycerides(1 glycerol and 3 fatty acids).There are two types of fats: non saturated and saturated. Looking at saturated fats, they only contain single carbon bonds in their hydrocarbon. Saturated fats are more unhealthy as they increase cholestrol levels which can lead to Coronary heart disease. They are usually solid at room temperature due to their high melting points and usually come from animals but there are plant sources such as coconut butter. Non saturated fats contain double carbon bonds in their hydrocarbon tail . They are usually liquid at room temperature and come from vegetable sources and they lower chlolestrol. There are two types of unsaturated fats, polyunsaturated and monounsaturated fats. Monounsaturated fats contain only 1 double carbon bond and polyunsaturated contain more than 1 double carbon bond

Soures:Fats should be 35% or less of your diet. According to the government, you should onl contain 70g of fat with a maximum of 20g. Saturated fat soures include butter, lard, suet and cheese. Monounsaturated fat sources are found in almonds,olive oil, peanut butter and avacados. Polysaturated fats contain more than 1 double carbon bond.

Excess: Too much fat can cause obesity due to the weight gain. Furthermore, this can cause type 2 diabetes from the ammount of energy having to be processed using insulin. Due to the cholestrol levels of the fat can cause coronary heart disease and heart diseases causing palipiations.

Defieciency: A lack of Fat soluble vitamins can cause a range of problems which can lead to severe consequences. Your body will lose weight and you will get colder faster as your layer of insulation is be thinner. This can also lead to the result of your body being weaker from knocks.

B3(Niacin): helps with energy release and maintains healthy nervous system and skin and is found in wheat, nuts, meat and fish. A defieciency can cause Pellagra(a disease causing fatigue, depression and a loss of energy

B9(Folic Acid): crucial for growing healthy babies and works with vitamin B12 to make red blood cells and is found in liver, peas and leafy greens. Defieciency can cause anaemia, tiredness, weak muscles and mouth sores. It is important for pregnant women as low levels at conception can cause spina bifda in babies

B12(Cobalamin): Helps the nervous sytem and works with B9 to make red blood cells and is foudn in milk, eggs, meat and fish. A defieciency can cause tirdness, nerve damage(in extreme calses)

Antidioxants: chemicals that protect us from free radicals which are chemicals that we encounter every day of our lives which can damage our body's cells which can lead to diseases such as cancer and heart disease. Vitamin A, C, and E have antioxidants.

Water soluble Vitamin Storage: All of these vitamins are lost so not much impact will occur having too much but having too much C can cause stomach pain and diarroea

Water: it controls body temperature, aids digestion and eliminates waste(excretion). Too much can cause nutrients to be more dilute which can make your kidneys stressed maybe leading to failiure. Too little can cause slower reaction times(your brain requires water), thicker blood(making it hard for your heart to pump blood) and increase in body temp as homeostasis can't occur without water.

Fibre: or known as Non startch Polysaccharide, a type of carbohydrate that helps your body moving food molecules through the digestive system. It is found in fruits and vegetables, wholemeal carbohydrates, lentils and beans. Too little can cause bowel/colon cancer, High blood pressure and constipation. The NHS recomends 30g of fibre a day

Teenagers Protein is required to cope up with growth spurts as musclar tissue begins to develop. Iron and Vitamin C irquired for Teenage girls who start their periods as they lose a lot of iron from periods and vitamin C helps absorb iron. Calvium and Vitamin D are needed to help the skelaton reach peak size and bone density.

Children(5-12): Children require protein to help them grow and repair the body. Furthermore, they should have carbohydrates and fats fr energy for growth and physical activity. Calcium and Vitamin D are also needed for healthy bond development. Foods that are high in sugar or saturated fats should be kept to aminimum to avoid obesity and tooth decay.

Toddlers/Young children(2-5): children shoud gradually move onto a diet related to the eatwell guide. Young children do not have large stomachs so they need to have small frquent meals. Milk is an essential source of eneryg as it contains a source of vitamin A and vitamin D. They should be frequentally encouraged to try new foods.

Adults: Growth and development stops so they should follow the eatwell guide. Men rquire more calories due their more lean msucle and are generally taller and bigger. Iron is required for periods. Calcium and vitamin D are important for all adults to reduce risk of bone diseases later as people substantial ammounts of bone strength after the menopause so these nutrients are needed to keep the skelaton strong. During Pregnancy, 200 more calories are required to support babies growth and to also consume more folic acid to reduce risks of birth defects.

Elderly Adults: Muscle decreases and it is more difficult to do more physical activity so fat can increase if their diet is still the same. Calucium and Vitamin D are required to stop bones developing diseases such as osteoporosis. Furtheromre Vitamin B12 is needed to keep brain healthy and prevent memory loss.Fibre prevents constipation as digestive system startst to weaken. Lastly vitamin a is needed to maintain good eyesight.

Obesity This can be foudn out by a person's BMI which is caucluated by your weight / height^2. Under 18.5 is underweight, over this till 25 is a healthy weight. 25 - 30 is overweight and 30 - 35 is obese. Past this and you are morbidly/extremely obese. BMI might not be that correct as you may are a substantial ammount of muscle mass. This can be cause by an incorrect balance of energy, eating lots of food in fat and sugar and doing no physcial activity. Health problems can range up to high blood pressure(increasing risk of CHD(Coronary heart Disease)), increased risk of type 2 diabetes and breathig difficulties, tiredness and low self esteem.

Coronary Heart Disease: when the coronary arteries are blocked by cholestrol and fatty depositys. This can be caused by eating lots of sturated fats., being physically inactive. smoking(damages lining of arteries and reduces oxygen in blood) and having high blood pressure(blood puts massive strains on organs and organs increasing heart diseases). This can cause a squeezing pain in your chest which can develop into other part of the body . Blood clots can suddenly occur as blood flow is blocked to the heart muscle as it does not get eneough oxygen causing a heart attack.