Why are proteins essential for the human body?

Answer 1

Protein is essential in your diet because it is needed for cell repair and for the growth of new cells. Protein is also required by the body so that it can perform basic bodily functions, including digestion and brain function.

Answer 2

Revision for protein

what is protein?

Behind water, protein is the most abundant substance in your body. Protein is made up of amino acids. When you digest food that contains protein your body breaks the protein down in to these amino acids.

When food is being digested the body selects the amino acids that are needed for a specific function and they are absorbed though the large intestine. There are 20 amino acids, each can be strung together in a different order in the body and this produces the different proteins. These proteins are needed to help develop and maintain your muscles and organs; in fact most of the bodies functions are reliant on there being enough protein.

Protein is not stored in the body in the same way as fats or carbohydrates so it is important that you regularly consume enough protein.

Without enough protein your body cannot function correctly. You may experience more illness, muscle atrophy and you will feel generally more run down. The correct amount of protein on the other hand assists in the building and maintenance of all body tissues and helps in the creation of enzymes and antibodies which are essential for all over body health.

why does the body need protein?

Protein is absorbed in to the body and broken down in to amino acids; this is essential for the correct Running of your body.

However out of the 20 amino acids that the body uses, only 11 can be produced by the body itself, these are called 'non-essential'.

The other 9 that must come from our food are called 'essential' and as the name suggests it is essential that we must get these amino acids through our diet.

So, our bodies need protein from food or supplementation to function correctly.

A complete protein is a source of protein that will contain all the essential amino acids the body needs, whereas an incomplete protein source will not. Examples of complete proteins are usually animal products such as meat. Incomplete proteins are usually found in plant sources such as seeds or nuts. Combining some of these incomplete protein sources will give you a meal that contains all the essential amino acids.

what foods are high in protein?

It is important to get enough protein through food before you start taking supplements, most food labels will show you the level of nutrients are contained in the food. To give you an idea of some food that you may regularly come across and it's protein content, please see the table below.

All amounts given are approximate and will vary depending on the quality / cut of the food, but it should give you an idea as to which foods are high in protein.

Chicken 100g - 27 grams of protein

Turkey 100g - 25 grams of protein

Beef 100g - 22 grams of protein

Fish 100g - 21 grams of protein

Lamb Chops 100g - 21 grams of protein

Duck 100g - 20 grams of protein

Cottage Cheese 100g - 14 grams of protein

Milk 1 glass / 250ml - 8 grams of protein

Egg medium sized - 8 grams of protein

Tofu 100g - 8 grams of protein

Should I eat all foods that are high in protein? Both fish and lamb chops have a similar amount.

Some foods will have a higher fat percentage, in the case of lamb chops, about 28 grams per 100g serving.

Fillets of white fish like cod or haddock have a lower fat percentage and may only contain around 1- 2 grams of fat.

Remember though that fat and carbohydrates are also essential for your body so don't try to cut them out of your diet altogether. By all means increase your protein intake, but not at the expense of other nutrients.

What are good vegetarian sources of protein?

As a vegetarian or vegan you can still get enough protein though food, good sources of protein are nuts, seeds, cereals and pulses. Tofu is an excellent vegetarian substitute for meat. Eating a combination of these, including pulses will ensure you can get all the essential amino acids you need.

There are many sites out there with recipe ideas to get you started. With minimal investigation you can find meal ideas that not only taste great, are really inexpensive too!

what is the best protein?

The effectiveness of protein is measured by it Biological Value (BV), this is how easily the body can absorb the protein and put it to use.

As protein can be assumed to be the only source of nitrogen for the body, tests are performed which measure the amount of nitrogen in urine. The less nitrogen passed in the urine, the more has been absorbed into the body. As the body has absorbed more nitrogen from this source, it is more effective; and its Biological Value is higher.

The main protein sources that you will encounter and their BV are:

Whey - 104

Egg - 100

Milk - 91

Beef - 80

Soy - 74

There are arguments about how a protein source can have a Biological Value over 100, but BV can be measured in 2 ways. Egg protein is set as the benchmark and has a relative BV of 100, its percentage BV however stands at 93.7% allowing whey protein to have a relative BV of over 100

how much protein do you need?

The answer varies from study to study, however per day about 45-50 grams of protein for women aged over 18 and about 55-60 grams of protein for men aged over 18 is needed for our bodies to function correctly.

For muscles to grow and tissue to repair your body needs enough protein; when taking up an activity such as a sport, or joining the gym the amount of protein your body requires will increase. Strength athletes and bodybuilders in particular need to increase their protein intake to get the most out of their training.

There is nowhere in the body for us to store protein like we do for example with fat. This means we must regularly consume enough protein to keep our bodies healthy. Supplements are an excellent way to keep up your protein intake.

In order to get the most out of your body you must put in enough fuel.

Is too much protein bad for you?

Although the body needs a certain amount of protein, too much can be harmful for a person's health.

There is a significant risk of high cholesterol, due to the high amount of saturated fats in certain foods, which could in turn lead to Heart disease and stroke.

Too much protein also puts a strain on the liver and kidneys. Foods that contain protein have high levels of nitrogen, which are harmful to the body and must be eliminated. The role of the kidneys is to filter out waste products and therefore an excess of protein will force the kidneys to work harder to remove the nitrogen waste from the body. This stress could ultimately lead to kidney disorders or damage to the body's filtering capacities.

Due to the inability of the body to store excess protein, any surplus protein that is consumed is then converted into glucose in the liver and either used up as energy or stored as fat.

Some protein-rich foods are high in nucleic acids, which when broken down, are converted into uric acid. Consequently, too much uric acid in the blood can lead to gout, an extremely uncomfortable condition that causes a person's joints to become inflamed, tender and agonizingly painful to move.

Finally, too much protein in the diet could also lead to osteoporosis (thinning of the bones), as an excess of protein promotes the loss of calcium in the bones through urine.

Can too little protein affect our health?

Just as too much protein is detrimental to our health, too little protein can also affect the body negatively.

Many foods containing protein are also good sources of iron amongst other minerals and vitamins. A lack of iron can result in tiredness and fatigue, leaving the body weak and with little energy.

Protein in the body is lost daily and therefore must be replenished daily through the diet. Too little protein can cause skin problems and generally give us an unhealthy and tired appearance.

Protein is needed to repair and create new cells, tissues, hormones, enzymes and muscles and a lack of protein can prevent these processes from being carried out correctly.

In children, who need a lot of protein to help them grow and develop, not enough protein can lead to a stunted growth and even poor mental development.

Answer 3

Your hair, your nails, and the outer layers of your skin are made of the protein keratin. Keratin is a scleroprotein, or a protein resistant to digestive enzymes. So if you bite your nails, you can't digest them.

Muscle tissue contains myosin, actin, myoglobin, and a number of other proteins.

Bone has plenty of protein. The outer part of bone is hardened with minerals such as calcium, but the basic, rubbery inner structure is protein; and bone marrow, the soft material inside the bone, also contains protein.

Red blood cells contain hemoglobin, a protein compound that carries oxygen throughout the body. Plasma, the clear fluid in blood, contains fat and protein particles known as lipoproteins, which ferry cholesterol around and out of the body.

Answer 4

Proteins are essential for helping to control and regulating the rate of chemical reactions.

Answer 5

It is essential for growth and repair of tissues, which still happens even if you are full grown.

Answer 6

Protiens are essencial for the body because they have vitamans that make you feel full so you dont overeat

Answer 7

To repair damaged tissues , for growth and to make enzymes

Answer 8

Protein is needed to keep muscles healthy.