Why is digestion important?

When you eat foods—such as bread, meat, and vegetables—they are not in a form that the body can use as nourishment. Food and drink must be changed into smaller molecules of nutrients before they can be absorbed into the blood and carried to cells throughout the body. Digestion is the process by which food and drink are broken down into their smallest parts so the body can use them to build and nourish cells and to provide energy.

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How is food digested?

Digestion involves mixing food with digestive juices, moving it through the digestive tract, and breaking down large molecules of food into smaller molecules. Digestion begins in the mouth, when you chew and swallow, and is completed in the small intestine.

· Foods Journey - Stop 1: The Mouth

· Foods Journey - Stop 2: The Pharynx and Esophagus

· Foods Journey - Stop 3: The Stomach and Small Intestine

· Foods Journey - Stop 4: The Colon, Rectum and Anus

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Stop 1: The Mouth

The mouth is the beginning of the digestive tract, and, in fact, digestion starts here before you even take the first bite of a meal. The smell of food triggers the salivary glands in your mouth to secrete saliva, causing your mouth to water. When you actually taste the food, saliva increases.

Once you start chewing and breaking the food down into pieces small enough to be digested other mechanisms come into play. More saliva is produced to begin the process of breaking down food into a form your body can absorb and use. In addition, "juices" are produced that will help to further break down food.

Stop 2: The Pharynx and Esophagus

Also called the throat, the pharynx is the portion of the digestive tract that receives the food from your mouth. Branching off the pharynx is the esophagus, which carries food to the stomach, and the trachea or windpipe, which carries air to the lungs.

The act of swallowing takes place in the pharynx partly as a reflex and partly under voluntary control. The tongue and soft palate -- the soft part of the roof of the mouth -- push food into the pharynx, which closes off the trachea. The food then enters the esophagus.

The esophagus is a muscular tube extending from the pharynx and behind the trachea to the stomach. Food is pushed through the esophagus and into the stomach by means of a series of contractions called peristalsis.

Just before the opening to the stomach is an important ring-shaped muscle called the lower esophageal sphincter (LES). This sphincter opens to let food pass into the stomach and closes to keep it there. If your LES doesn't work properly, you may suffer from a condition called GERD, which causes heartburn and regurgitation (the feeling of food coming back up).

Stop 3: The Stomach and Small Intestine

The stomach is a sac-like organ with strong muscular walls. In addition to holding food, it serves as the mixer and grinder of food. The stomach secretes acid and powerful enzymes that continue the process of breaking the food down and changing it to a consistency of liquid or paste. From there, food moves to the small intestine. Between meals the non-liquefiable remnants are released from the stomach and ushered through the rest of the intestines to be eliminated.

Made up of three segments -- the duodenum, jejunum and ileum -- the small intestine also breaks down food using enzymes released by the pancreas and bile from the liver. Peristalsis is also at work in this organ, moving food through and mixing it up with the digestive secretions from the pancreas and liver, including bile. The duodenum is largely responsible for the continuing breakdown process, with the jejunum and ileum being mainly responsible for absorption of nutrients into the bloodstream.

While in the small intestine nutrients from food are absorbed through the walls of the intestine and into the bloodstream. What's leftover (the waste) moves into the large intestine (large bowel or colon).

Everything above the large intestine is called the upper GI tract. Everything below is the lower GI tract.

Stop 4: The Colon, Rectum and Anus

The colon (large intestine) is a five- to seven -foot -long muscular tube that connects the small intestine to the rectum. It is made up of the ascending (right) colon, the transverse (across) colon, the descending (left) colon and the sigmoid colon, which connects to the rectum. The appendix is a small tube attached to the ascending colon. The large intestine is a highly specialized organ that is responsible for processing waste so that defecation (excretion of waste) is easy and convenient.

Stool, or waste left over from the digestive process, passes through the colon by means of peristalsis, first in a liquid state and ultimately in solid form. As stool passes through the colon, any remaining water is absorbed. Stool is stored in the sigmoid (S-shaped) colon until a "mass movement" empties it into the rectum, usually once or twice a day.

It normally takes about 36 hours for stool to get through the colon. The stool itself is mostly food debris and bacteria. These bacteria perform several useful functions, such as synthesizing various vitamins, processing waste products and food particles, and protecting against harmful bacteria. When the descending colon becomes full of stool it empties its contents into the rectum to begin the process of elimination.

The rectum is an eight-inch chamber that connects the colon to the anus. The rectum:

• Receives stool from the colon
• Lets the person know there is stool to be evacuated
• Holds the stool until evacuation happens

When anything (gas or stool) comes into the rectum, sensors send a message to the brain. The brain then decides if the rectal contents can be released or not. If they can, the sphincters relax and the rectum contracts, expelling its contents. If the contents cannot be expelled, the sphincters contract and the rectum accommodates so that the sensation temporarily goes away.

The anus is the last part of the digestive tract. It consists of the muscles that line the pelvis (pelvic floor muscles) and two other muscles called anal sphincters (internal and external).

The pelvic floor muscle creates an angle between the rectum and the anus that stops stool from coming out when it is not supposed to. The anal sphincters provide fine control of stool. The internal sphincter is always tight, except when stool enters the rectum. It keeps us continent (not releasing stool) when we are asleep or otherwise unaware of the presence of stool. When we get an urge to defecate (go to the bathroom), we rely on our external sphincter to keep the stool in until we can get to the toilet.

Accessory Organs

Pancreas

Among other functions, the pancreas is the chief factory for digestive enzymes that are secreted into the duodenum, the first segment of the small intestine. These enzymes break down protein, fats and carbohydrates.

Liver

The liver has multiple functions, but two of its main functions within the digestive system are to make and secrete an important substance called bile and to process the blood coming from the small intestine containing the nutrients just absorbed. The liver purifies this blood of many impurities before traveling to the rest of the body.

Gallbladder

The gallbladder is a storage sac for excess bile. Bile made in the liver travels to the small intestine via the bile ducts. If the intestine doesn't need it, the bile travels into the gallbladder where it awaits the signal from the intestines that food is present. Bile serves two main purposes. First, it helps absorb fats in the diet and secondly, it carries waste from the liver that cannot go through the kidneys.

HORMONES

The main hormones that control digestion are gastrin, secretin, and cholecystokinin (CCK):

• Gastrin causes the stomach to produce an acid for dissolving and digesting some foods. Gastrin is also necessary for normal cell growth in the lining of the stomach, small intestine, and colon.
• Secretin causes the pancreas to send out a digestive juice that is rich in bicarbonate. The bicarbonate helps neutralize the acidic stomach contents as they enter the small intestine. Secretin also stimulates the stomach to produce pepsin, an enzyme that digests protein, and stimulates the liver to produce bile.
• CCK causes the pancreas to produce the enzymes of pancreatic juice, and causes the gallbladder to empty. It also promotes normal cell growth of the pancreas.

Nerve Regulators

Two types of nerves help control the action of the digestive system.

Extrinsic, or outside, nerves come to the digestive organs from the brain or the spinal cord. They release two chemicals, acetylcholine and adrenaline. Acetylcholine causes the muscle layer of the digestive organs to squeeze with more force and increase the “push” of food and juice through the digestive tract. It also causes the stomach and pancreas to produce more digestive juice. Adrenaline has the opposite effect. It relaxes the muscle of the stomach and intestine and decreases the flow of blood to these organs, slowing or stopping digestion.

The intrinsic, or inside, nerves make up a very dense network embedded in the walls of the esophagus, stomach, small intestine, and colon. The intrinsic nerves are triggered to act when the walls of the hollow organs are stretched by food. They release many different substances that speed up or delay the movement of food and the production of juices by the digestive organs.

Together, nerves, hormones, the blood, and the organs of the digestive system conduct the complex tasks of digesting and absorbing nutrients from the foods and liquids you consume each day.

A good diet is central to overall good health, but which are the best foods to include in your meals, and which ones are best avoided?

CARBOHYDRATES

Bread, cereals and potatoes

This food group also contains pasta, rice and noodles and is full of starchy carbohydrates - your body's main source of energy.

Unrefined and refined carbohydrates

Apart from potatoes, all the foods listed in this group began life as a grain, such as wheat, rye, corn, rice or barley. Potatoes and grains are very healthy and filling; however, you can be even healthier if you choose unrefined versions of these foods over refined versions.

Refined carbohydrates refers to foods where machinery has been used to remove the high fibre bits (the bran and the germ) from the grain. White rice, white bread, sugary cereals, and pasta and noodles made from white flour are all examples of refined carbohydrates.

Unrefined carbohydrates still contain the whole grain, including the bran and the germ, so they're higher in fibre and will keep you feeling fuller for longer - great if you're trying to lose weight and hate feeling hungry. Examples include wholegrain rice, wholemeal bread, porridge oats and wholewheat pasta.

Simple and complex carbohydrates

These are often confused with refined and unrefined carbohydrates, but the terms simple and complex refer to how complicated the chemical structure of a carbohydrate is rather than to whether it's wholegrain or not. Complex carbohydrates are the most common and there are three kinds:

Glycogen. This is your body's major fuel source and is sometimes referred to as blood sugar. It's formed from glucose, which is found in almost all foods, and is converted into energy.

Starch. This is only found in plants and, contrary to popular belief, isn't fattening (it's the rich sauces, fats and oils often added to pasta, potatoes, rice, noodles and bread that are the culprits!).

FIBRE is an important component of a healthy balanced diet. We get fibre from plant-based foods, but it's not something the body can absorb. This means fibre is not a nutrient and contains no calories or vitamins. If you decide to increase the amount of fibre you eat, try to drink more water too. Your body doesn't digest fibre, so you need the extra water to help it flow through your digestive system with ease.

• Fibre helps your digestive system to process food and absorb nutrients.
  
• Fibre lowers blood cholesterol.
  
• Fibre helps to control blood sugar levels, which in turn controls appetite.
  

There are two types of fibre: insoluble and soluble.

Insoluble fibre

Insoluble fibre contains cellulose, hemicellulose and lignin. It helps your bowel to pass food by making stools soft and bulky. This type of fibre helps prevent constipation.

Insoluble fibre is found in the following foods:

• beans
  
• brown rice
  
• fruits with edible seeds
  
• lentils
  
• maize
  
• oats
  
• pulses
  
• wheat bran
  
• wholegrain breads
  
• wholegrain cereals
  
• wholemeal breads
  
• wholemeal cereals
  
• wholemeal pasta
  
• wholewheat flour.
  

Soluble fibre

Soluble fibre contains gums and pectin. This type of fibre lowers cholesterol levels and controls blood sugar. It can be found in all fruit and vegetables, but the following are rich sources:

• apples
  
• barley
  
• citrus
  
• guar gum
  
• legumes
  
• oats
  
• pears
  
• strawberries.
  

Fibre (non-starch polysaccharide). This is abundant in unrefined carbohydrates, fruit and vegetables, and is important because it helps your body to process waste efficiently and helps you to feel fuller for longer.

FRUIT AND VEGETABLES

Fruit and vegetables are brimming with fibre, plus a whole range of vitamins and minerals, and because they're low in calories, they make an important and healthy addition to any diet.

Scientific studies have shown that people who eat a lot of fruit and vegetables may have a lower risk of getting illnesses, such as heart disease and some cancers. For this reason, health authorities recommend that you eat at least five portions of fruit and vegetables every day - and it doesn't matter whether they're fresh, tinned, frozen, cooked, juiced or dried.

One piece of medium-sized fruit - eg, an apple, peach, banana orange One slice of large fruit, such as melon, mango or pineapple

• One handful of grapes or two handfuls of cherries or berry fruits
• One tablespoon of dried fruit
• A glass (roughly 100ml) of fruit or vegetable juice
• A small tin (roughly 200g) of fruit
• A side salad
• A serving (roughly 100g) of vegetables - eg, frozen or mushy peas, boiled carrots or stir-fried broccoli
• The vegetables served in a portion of vegetable curry, lasagne, stir-fry or casserole

VITAMINS Eating a wide variety of fruit and vegetables means you're more likely to get all the vitamins and minerals you need. But what are vitamins - and why are they so important to your good health?

• Vitamins are organic substances - this means they're found in plants and animals.
• Most vitamins can't be made by your body, so they must be sourced from your diet. Vitamin D and the B vitamin niacin are exceptions to this.
• Nutritionists have divided vitamins into two groups: fat-soluble and water-soluble.
• The fat-soluble vitamins - A, D, E and K - are transported through your body by fat. They can also be stored in your fat and liver cells for a limited period of time.
• The water-soluble vitamins - B and C - are absorbed by and transported through your body in water. They need to be eaten every day, as you can't store them for any length of time.

Fat-soluble vitamins

Vitamin	Why important?	Where found?	Daily Recommendation
Vitamin A	It looks after your eyes, the lining of your nose, throat and lungs, and your skin cells.	Carrots, sweet potatoes, pumpkins, red chillies, tomatoes, 'orange' fruits, such as apricots and mango, and dark green leafy vegetables.	600µg for females, 700µg for males.
Vitamin D	It helps your body to absorb calcium, needed to ensure strong bones and teeth.	The most important source is the sun, but it's also found in tiny amounts in dairy products, cod liver oil and oily fish.	No recommendation as sunlight is the main source.
Vitamin E	It fights free radicals - unbalanced molecules that can cause damage to your cells. It also contributes to the healthy condition of your skin.	Vegetables, poultry, fish, fortified breakfast cereals, vegetable oils, nuts and seeds.	Up to 4mg for adult males and up to 3mg for adult females is considered a safe intake.
Vitamin K	It helps your body to make a number of proteins, one of which helps your blood to clot.	Dark green leafy vegetables such as Brussels sprouts, broccoli, cabbage, spinach and asparagus. It's also found in soya oil and margarine.	1µg for every kg of body weight is considered a safe intake for both men and women.

Water-soluble vitamins

Vitamin	Why important?	Where found?	Daily recommendation
B-complex Vitamins	They help you to metabolise your food and help your blood cells to form and flow.	Green vegetables, wholegrains, meat, such as liver, kidneys, pork, beef and lamb, vegetable extracts, nuts and fortified breakfast cereals.	Eight vitamins make up the B-complex family: B1 (Thiamin) - Adult male, 0.9mg. Adult female, 0.8mg. B2 (Riboflavin - Adult male, 1.3mg. Adult female, 1.1mg. B3 (Niacin) - Adult male, 17mg. Adult female, 13mg. B5 (Pantothenic Acid) - 3 to 7mg is considered a safe intake for both sexes. B6 (Pyridoxine) - Adult male, 1.4mg. Adult female, 1.2mg. B9 (Folate) - 200 mcg for both adult males and females. B12 (Cobalamin) - 1.5 µg for both adult males and females. Biotin - 10-20 µg is considered a safe intake for both sexes.
Vitamin C	It helps your body to produce collagen (important for skin and bone structure) and to absorb iron.	A wide variety of vegetables and fruit, including spinach, broccoli, tomatoes, strawberries, citrus fruit and potatoes.	40mg for both adult male and female.

MINERALS Vitamins aren't the only nutrients to be gained from fruit and vegetables. Minerals also have an important role to play in your good health.

• Minerals are inorganic substances. This means they're found in the rocks and soil.
• Vegetables absorb mineral goodness as they grow, while animals digest it through their diet.
• Like vitamins, minerals can also be divided into two groups - those that are needed in minute quantities and those that are needed in larger quantities.
• Minerals needed in larger amounts - the major minerals - include calcium, magnesium, sodium, potassium and phosphorus.
• Minerals needed in tiny amounts are called trace minerals. This group includes iron, zinc, iodine, selenium and copper.

Major minerals

Mineral	Why important?	Where found?	Daily recommendation
Calcium	It's essential for healthy bones and teeth.	It's in abundance in milk and dairy products. Very small quantities can be found in dark green leafy vegetables, such as spinach and watercress.	700mg for males and females.
Phosphorous	It contributes to healthy cells, bones and teeth.	You'll find it in milk, cheese, fish, meat and eggs.	550mg for males and females.
Magnesium	It helps your body to use energy and your muscles to function effectively.	Dark green leafy vegetables, such as cabbage and broccoli.	300mg for males and females.
Sodium	It helps your body to regulate its water content and your nerves to function effectively.	As table salt, added to food for flavour.	1,600mg for males and females.
Potassium	It helps your cells and body fluids to function properly.	In most foods, apart from fats, oil and sugar.	3,500mg for males and females.

Trace minerals

Mineral	Why important?	Where found?	Daily recommendation
Iron	It helps in the formation of red blood cells; deficiency can lead to anaemia.	Red meat, fortified cereals and bread, some fruit and vegetables.	8.7mg for males. 14.8 for females, but more if you experience a heavy menstrual flow.
Zinc	It helps the body to reach sexual maturity and aids the repair of damaged tissue.	Meat, fish, milk, cheese and eggs.	9.5mg for males. 7mg for females.
Copper	It helps your body to use iron properly.	Green vegetables and fish.	1.2mg for both males and females.
Selenium	It ensures healthy cells.	Meat, fish, cereals, eggs and cheese.	75µg for males. 60µg for females.
Iodine	It helps to make thyroid hormones, which control metabolic activity.	Seafood and dairy products.	140µg for both males and females.

PROTEINS

This food group includes poultry, pulses, beans, nuts, seeds, soya products and vegetable protein foods such as quorn and seitan. They're grouped together because they're all rich in protein.

Types of protein

Protein plays an essential role in building and repairing your body. But whether it helps a fingernail to grow or heals a sore muscle, for example, depends on the make-up of the protein.

Proteins consist of smaller units called amino acids, which can link together in many combinations to form chains. Some amino acid chains are created by your body, but those called essential amino acids must come from your diet. Although all animal and plant cells contain some protein, the amount and the quality of the protein varies a lot.

High biological value foods contain enough indispensable amino acids for an adult diet and are considered to be good quality protein. Meat, fish and eggs sit in this category.

Low biological value foods don't contain enough indispensable amino acids. Plant foods, such as pulses, nuts and seeds, are in this group.

Foods such as eggs, nuts, seeds, beans, pulses, vegetable protein foods and soya products all contain protein. There are also small amounts in grains and dairy products.

Eggs contain all eight essential amino acids, making them a perfect source of protein.

CALCIUM

Milk and dairy

This food group includes milk, cheese, yoghurt and fromage frais - but not butter, margarine or cream, which belong in the fat and sugar group. The foods in this group contain many different types of nutrients, but are particularly rich in calcium.

The importance of calcium

Calcium is a mineral that strengthens your bones and teeth, and ensures everything runs smoothly with your muscles and nerves. It's especially important for growth. Calcium can continue to add to the strength of your bones until you reach the age of 30 to 35, when peak bone mass is reached.

After this point, as a natural part of the ageing process, your bones lose their density and grow weaker. If you haven't had enough calcium in your diet prior to this, there's an increased risk that your bones won't be strong enough to cope with any weakening, which can result in the brittle bone disease, osteoporosis.

Health professionals estimate that one in three women and one in 12 men over the age of 50 suffer from osteoporosis. There's also concern that the diets of teenage girls and young women, in particular, aren't high enough in calcium. Some experts predict the future could bring an osteoporosis epidemic in women.

Calcium for vegans and the lactose intolerant

Of course, if your diet excludes milk and dairy products or if you can't tolerate the milk sugar lactose, then you need to look for calcium alternatives. You can keep your bones healthy by:

• buying soya milks, yoghurts and cheeses enriched with calcium
• eating lots of dark green leafy vegetables, such as spinach, broccoli and watercress
• using almonds or sesame seeds as topping on salads, cereals or desserts
• snacking on dried fruits - apricots, dates and figs all contain small amounts of calcium
• if you're not vegan, adding sardines, prawns or anchovies to a main meal

FATS and SUGARS

.

The foods in this group are best eaten sparingly because, although an energy source, they contain few nutrients. Don't be fooled into thinking they're entirely 'bad', though. Fat is an important contributor to good health.

fat facts

• Fat transports fat-soluble vitamins A, D, E and K through your body.
• It cushions your internal organs.
• It makes food taste nicer.
• It can contain essential fatty acids (EFAs), which are thought to have a positive effect on the health of your heart and immune system.
• It's a concentrated source of energy.

It's this last point that has given fat such a bad reputation. Just 1g of fat provides 9 calories - more than double the calories in 1g of protein or carbohydrate. This means if you eat a lot of fatty foods, you're likely to put on weight. However, understanding the difference between unsaturated and saturated fats can help.

Saturated and unsaturated

Fat can be divided into two groups - saturated and unsaturated.

Saturated fat is generally solid at room temperature and is usually from animal sources. It's found in lard, butter, hard margarine, cheese, whole milk and anything that contains these ingredients, such as cakes, chocolate, biscuits, pies and pastries. It's also the white fat you can see on red meat and underneath poultry skin. The less saturated fat you eat, the better - a high intake has been linked with an increased risk of coronary heart disease.

Unsaturated fat is usually liquid at room temperature and generally comes from vegetable sources. Monounsaturated and polyunsaturated fats are both included in this group. Unsaturated fat is a healthier alternative to saturated fat and can be found in vegetable oils such as sesame, sunflower, soya and olive; oily fish, such as mackerel, sardines, pilchards and salmon; and soft margarine.

Sugary foods

Like fat, sugar is a concentrated source of energy and also has a bad reputation. The psychological benefits of eating foods such as jam, sweets, cakes, chocolate, soft drinks, biscuits and ice cream are fairly obvious. They taste lovely and feel like a special treat. However, it's important to keep them as just that - an occasional, special treat. Why? Because...

• Sugary foods often go hand in hand with fatty foods. Think cakes, biscuits, chocolate and pies.
• Sugar interacts with the plaque on your teeth and has been proven to cause tooth decay.

Nutrition

Better nutrition means stronger immune systems, less illness and better health. Better nutrition is a prime entry point to ending poverty and a milestone to achieving better quality of life. Nutrition is an input to and foundation for health and development. Interaction of infection and malnutrition is well-documented. Healthy people are stronger, are more productive and more able to create opportunities to gradually break the cycles of both poverty and hunger in a sustainable way.

Food nourishes the body and gives us energy to get through each day. Healthy eating is fundamental to good health and is a key element in healthy human development, from the prenatal and early childhood years to later life stages. Healthy eating is equally important in reducing the risk of many chronic diseases. The most important determinants of good health are what we eat and how active we are.

Eat a plant-based diet rich in fruits, vegetables, and whole grains; choose healthy fats, like olive and canola oil; and red meat and unhealthy fats, like saturated and trans fats, sparingly. Most important of all is keeping calories in check, so you can avoid weight gain, which makes exercise a key partner to a healthy diet.

EIGHT WAYS OF EATING RIGHT

Choose good carbs, not no carbs. Whole grains are your best bet. Pay attention to the protein package. Fish, poultry, nuts, and beans are the best choices. Choose healthy fats, limit saturated fat, and avoid trans fat. Plant oils, nuts, and fish are the healthiest sources. Choose a fiber-filled diet, rich in whole grains, vegetables, and fruits. Eat more vegetables and fruits. Go for color and variety—dark green, yellow, orange, and red. Calcium is important. But milk isn't the only, or even best, source. Moderate drinking can be healthy—but not for everyone. You must weigh the benefits and risks. A daily multivitamin is a great nutrition insurance policy. Some extra vitamin D may add an extra health boost.
HEALTHY EATING PYRAMID

The Health Eating Pyramid is a simple, trustworthy guide to choosing a healthy diet. Its foundation is daily exercise and weight control, since these two related elements strongly influence your chances of staying healthy.

1. Start with exercise. A healthy diet is built on a base of regular exercise, which keeps calories in balance and weight in check.

2. Focus on food, not grams. The Healthy Eating Pyramid doesn’t worry about specific servings or grams of food, so neither should you. It’s a simple, general guide to how you should eat when you eat.

3. Go with plants. Eating a plant-based diet is healthiest. Choose plenty of vegetables, fruits,

whole grains, and healthy fats, like olive and canola oil.

4. Cut way back on American staples. Red meat, refined grains, potatoes, sugary drinks, and salty snacks are part of American culture, but they’re also really unhealthy. Go for a plant-based diet rich in non-starchy vegetables, fruits, and whole grains. And if you eat meat, fish and poultry are the best choices.

5. Take a multivitamin, and maybe have a drink. Taking a multivitamin can be a good nutrition insurance policy. Moderate drinking for many people can have real health benefits, but it's not for everyone. Those who don’t drink shouldn’t feel that they need to start.

Our bodies get the energy and nourishment they need from our daily diet. Not having enough of the right food, or eating too much of the wrong food causes ill-health. Many people in developed countries are overweight because they take little exercise, and eat too much fatty food, which makes them unfit, and often unhealthy. Anything humans can digest counts as food. Worldwide diets vary widely.

Food habits are influenced by availability, climate, and religious, moral, or social factors. A daily diet should include staple energy-giving carbohydrates, such as rice or pasta, plus proteins such as beans, peas, eggs, meat. The diet should also have fats, vitamins (fruits, vegetables), and minerals (milk and milk products). Sugars and honey sweetens food. Spices and herbs add flavor to a meal. Nuts and seeds can be pressed to make oils. Fats and oils store energy. In reality, poverty or warfare make this impossible in many places. Many countries have a distinctive cooking style, which reflects the eating habits of its people, and the ingredients available locally. There are many cooking methods, such as simmering food in water which heats it to just under low temperature, grilling or frying in oil heats food to a much high temperature, cooking it faster.

In many industrialized nations, cooking is a hobby, as well as a necessary task. Today, there is concern about the chemicals in food, and many people choose an organic diet. Many foods are indigestible without processing. Grating, pressing and heating the roots removes the deadly cyanide present in the food. Although some foods, such as salad vegetables and fruit, are delicious when raw, many foods need to be cooked first. Cooking makes food tastier and easier to digest. Cooking root vegetables, makes their starch grains absorb water, swell and burst, that releases essential nutrients.

How To Preserve Food

Preserving food is a fun and economical way to enjoy good food long after harvest season is finished. There is some basic knowledge required to help in understanding the process of preserving methods and to make preserving food safe. The key to enjoying preserved foods is to start with high quality, fresh products. Preserving food allows it to be stored for use later, that reduces the risk of shortages and prolongs availability.

Fast food is the term given to food that can be prepared and served very quickly. While any meal with low preparation time can be considered to be fast food, typically the term refers to food sold in a restaurant or store with low quality preparation and served to the customer in a packaged form for take-out/take-away. Fast food is food that is mass prepared and served quickly in takeaway outlets.

If a machine is treated with care and given proper maintenance, it is more likely to function efficiently. Similarly, the human body is most likely to function to the best of its ability if it is kept fit and healthy. If people are fit, they can deal with the requirements put upon their bodies by everyday activities, such as walking and lifting. People’s health may suffer as they become older, if they eat a poor diet, if they are poor, if they are exposed to pollution, or work in a harmful environment. By following a balanced diet with plenty of fresh fruits and vegetables and not too much fat, combined with regular exercise, aid better health.

Balanced Diet Plate

A healthy diet consists of the right amounts of protein, carbohydrate, fat vitamins, minerals, and fibre. Fruit and vegetable are full of vitamins. Fish provides energy, iron and protein. Dairy products provide protein and fat. Meat is full of protein and vitamins. Nuts and fungi contain protein and minerals. Pulses, rice, and pasta provide carbohydrates.

The human body is most likely to function to the best of its ability if it is kept fit and healthy. Health may be defined as the state of being well in body and mind. When someone is in good health it means their body is working to its full potential and is not impended by physical or mental diseases. Fitness is an indication of how effectively the body’s muscles, heart, and lungs are working. The human body requires exercise to improve fitness. Exercise makes the heart and lungs work more efficiently, and strengthen muscles and bones. Regular relaxation reduces stress and tension, increases a sense of well-being, and decreases the risk of disease. Mental health is the fitness of the mind. Problems may be caused by hereditary or emotional problems caused by relationships or lifestyle. Keeping fit, discussing problems, and seeking professional help can improve a person’s mental health.