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A guide to

What are
functional foods?

Probiotics &
your health

Obesity –
an Irish epidemic

Nutrition & pregnancy

Your digestive system

The role of vitamins & minerals

Finland – a case
study in healthy

Health Calculators

What makes up a good diet?
Where does the energy in food come from?
What are calories/kilocalories?
How does our body use the energy obtained from food?
What are macronutrients and micronutrients?
How does the body use and store macronutrients?
What is your metabolic rate and can you increase it?
What are recommended dietary allowances (RDAs)?
What is the recommended amount of protein, fat and carbohydrate in the diet?
Why is breastfeeding so good for my baby?
What is weaning?
What kind of food should I give my baby?
Are there any foods that I shouldn’t give my baby?
What sort of diet is appropriate for two to fives?
Why is good nutrition so important for teenage girls?
Why is good nutrition so important for teenage boys?
Why is good nutrition important in older people?
What factors affect the dietary intake of older people?
What are the main dietary guidelines for older people?
Is there any such thing as a slimming diet that works?

What makes up a good diet?
While it is untrue to say that one particular food is good or bad, a good dietisone that has plenty of variety, because your body requires certain nutrients,suchas protein, carbohydrates and fibre, to function properly. Eating too littlemeansthat youmay lack sufficient energy or essential vitamins or minerals, while eating toomuch of one particular food may mean that you receive too much fat (and too littlevitamins and minerals) and therefore receive too much energy, leading to weightgain.

The Food Pyramid (see graphic below) has been developed to help you to visualise how a healthy diet can be achieved. At the base of the Pyramid are the 'starchy' foods such as breads, cereals and potatoes. These should be eaten plentifully - six or more servings a day are recommended. Next in the Pyramid are fruit and vegetables - you should aim for four or more servings a day.

Towards the top are milk, cheese, fish, eggs, and meat.Ideally you should stick to two to three servings a day from this group. On the top of the Pyramid are oils and fats such as butter and margarine, as well as sugars, cakes, biscuits and high-fat snacks. The rule in this group is to eat them only in small amounts, and not too often.

Where does the energy in food come from?
In order for our bodies to carry out any functions at all, from activities as simple as breathing to running a marathon and every other activity in between, we need energy. We
acquire this energy by eating food. Therefore, the body’s goal is to digest food and use the energy produced to keep it alive.

There are six basic components of food:
Carbohydrates, including fibre

Food and drink provide the body with energy from four of these forms - carbohydrate, fat, protein and alcohol. Each of these fuels supplies a different amount of energy. The amount of energy you use is measured in calories (for definition, see below).

Carbohydrate = 4 kilocalories (kcal) per gram
Fat = 9 kilocalories (kcal) per gram
Protein = 4 kilocalories (kcal) per gram
Alcohol = 7 kilocalories (kcal) per gram

What are calories/kilocalories?
In nutritional terms, calories and energy are more or less the same thing. A calorie is a unit of energy and the amount of calories in a food is a measure of how much potential energy it contains. A thousand calories make up a kilocalorie or Calorie (with a capital C). 1 kilocalorie (kcal) = 4.18 kilojoules (kJ). However, when we refer to calories with a small ‘c’, we really mean kilocalories.

Most food packaging contains details of the amount of calories and kilojoules (kJ) it contains, which indicate the amount of energy in a particular food. However, the calories listed on a food package are actually kilocalories (1000 calories = 1 kilocalorie).

Examples of calories in some common foods:
Roasted peanuts
One packet of popcorn
One doughnut
Bag of chips
Rasher sandwich
Beans on toast
Bowl of Rice Crispies and milk
Yoghurt (plain)
Yoghurt (fruit)

Energy (kcal)

How does our body use the energy obtained from food?
Our bodies ‘burn’ calories by breaking down the food we eat into molecules. Substances known as enzymes, produced by the body, break the carbohydrates into glucose and other sugars, the fats into glycerol and fatty acids, and the proteins into amino acids. These molecules are then transported through the bloodstream to the cells, where they are either absorbed for immediate use or are combined with oxygen, which releases their stored energy.

When you eat food you take in calories and by eating more food or food containing more calories than your body consumes, over the course of several days, weeks or months, your body will convert the excess energy to body fat. To lose one pound of fat, you have to burn off 3,500 excess calories. You can do that either by exercising, which will burn up the energy stored as fat or by restricting your food/calorie intake.

What are macronutrients and micronutrients?
Most foods contain a mixture of carbohydrates, protein and fat, known as macronutrients. Because the body needs more of them, macronutrients have hence earned their name. Food also contains a range of vitamins and minerals, which are known as micronutrients.
Although these micronutrients are essential, they are only needed in very small amounts. Therefore, a varied diet is important to ensure a healthy intake of a mix of nutrients.
Micronutrients do not contain energy but macronutrients do.

How does the body use and store macronutrients?

It is thought that the body uses carbohydrates as its main source of energy, followed by protein and fat. Alcohol is also an energy source that is broken down or metabolised first when it is consumed, as it cannot be stored in the body and because high levels are poisonous.

What is your metabolic rate and can you increase it?

The rate at which your body uses energy is known as the metabolic rate, which can be increased by increasing the amount of lean tissue (muscle mass, through training/exercise) in the body.

The resting metabolic rate (RMR) is the amount of energy you use simply to keep alive, through breathing, pumping blood around your body and so forth and is over two-thirds of the energy used by your body. The more active you are, the more energy you use.

What is the recommended amount of protein, fat and carbohydrate in the diet?

The requirements of protein, fat and carbohydrates for men and women vary, dependingon age and in women, pregnancy, lactation (breastfeeding). However, as a generalguideline, 50% of energy should be sourced from carbohydrates, 35% from fatsand 15% from proteins.

What are recommended dietary allowances (RDAs)?
Recommended dietary allowances are the level of nutrients deemed to be adequate to meet the needs of practically all healthy people, and are devised based on scientific knowledge. They are also known as recommended daily allowances, recommended daily amounts and recommended nutrient intakes.

RDAs are prepared by nutrition experts in individual countries and are used to evaluate if food meets national nutrition needs, for designing nutrition education programmes and for developing new products. The Irish RDAs were published in 1999 by the Food Safety Authority.

Why is breastfeeding so good for my baby?
For the first few months of life, infants only need milk as a source of energy. Breast milk is a complete food as it contains exactly the right blend of nutrients and it changes to suit the baby’s changing needs. It is always sterile, at the correct temperature and available, regardless of where the mother and baby are.

Because it contains antibodies, it helps to protect the baby from disease while the baby’s own antibody-forming system is still maturing during the first few months. It also helps protect against allergies and conditions such as asthma and eczema. Maternal illness does not usually affect the baby but it may temporarily reduce milk levels.

Newborns are usually fed at least once every three hours, although this can vary immensely, as any new parent will tell you! This is because breast milk is more quickly digested and therefore breastfed babies usually need to be fed more frequently than bottle-fed babies. It can take two or three months before they settle into a four-hourly feeding routine.

On the other hand, bottle-feed contains more calories than breast milk and so may delay feelings of hunger for longer. This is another reason why a breast-fed baby may need to be fed more frequently. However, despite this, breast-fed babies are not usually overweight as it is easier to overfeed a bottle-fed baby. Breastfed babies also tend to experience less evening colic.

What is weaning?
As the baby grows and becomes more active, their energy requirements increase and a milk-only diet can no longer fulfil these needs. Weaning occurs when a baby is introduced to solid food and it usually commences when the baby is between four and six months old.

Babies younger than four months don't have a fully developed gastrointestinal tract. Also, they cannot bite and chew, and they don’t usually like different tastes and textures so it is best not to start before this age. They are also more susceptible to allergic reactions and feeding too soon can cause the baby to become overweight. Weaning too soon can also cause stomach upset, constipation or diarrhoea, along with excessive weight gain. It can also prevent the baby from getting enough breast-milk or formula.

However, the baby needs to develop a ‘taste’ for foods before they need it, so it is a good idea to introduce solids by the age of six months, when your baby will have used up the store of iron they were born with.

The baby is probably ready to be weaned when their birth weight has doubled, they can sit with support and can control their head and neck.

What kind of food should I give my baby?
First solids should be smooth, semi-liquid and bland, as the baby will not eat them otherwise. New foods should be introduced slowly, as different tastes and textures will take some getting used to.

Pureed meat, poultry and fish should be introduced between six and eight months and you should aim to have your child eating ‘lumpy’ food by nine months of age.
At around seven to nine months of age, babies usually enjoy eating finger foods, including toast, unsalted crackers, small soft pieces of cooked vegetables, soft ripe fruits and cheese.

By one year of age, a baby will probably have tripled its birth weight. However, between one and four years of age, the child’s growth rate slows. As a result of this slowdown in growth, their appetite may decrease.

By 15 months of age, most children are able to feed themselves without help. Their basic nutritional needs are similar to the nutritional needs of other family members, differing only in the lesser amounts needed.

At this age the child should be offered a variety of foods from the basic food groups:
Breads, cereals, rice, potatoes and pasta
Vegetables and fruits
Milk, yoghurt and cheese
Meats, poultry, fish, dry beans and peas, and eggs.

Small children can become dehydrated more quickly than adults and they will require water several times during the day. Fat should not be restricted in children under the age of two.

Are there any foods that I shouldn’t give my baby?
Citrus fruits, egg white, shellfish, nuts, cow’s milk and chocolate should not be given to a baby before one year of age as these foods may cause allergic reactions and allergies. Spinach, turnip and beetroot are also inadvisable for babies under six months old.

Firm foods that slide down the throat without the need to be chewed, such as sweets, peanuts, grapes, nuts, seeds and pieces of raw carrot should also be avoided as they are a possible choking hazard. Likewise, peanut butter, tough meat and dried fruits, raisins or dates should also be avoided. Peanuts can also cause severe allergies.

Honey sometimes contains spores that can cause a serious infection called infant botulism in children under a year. Sweets, chocolate, sugar, jam, syrup and sugar coated breakfast cereals may also decrease a baby’s appetite and are not good for developing teeth.

What sort of diet is appropriate for two to fives?

By the time your child is two, they will have developed definite tastes for certain foods and most children will let you know this quite quickly! However, don't worry if your child refuses to eat a well balanced diet every day because if they are growing normally, there is usually no cause for concern.

There are a number of things you can try to ensure that they receive a balanced diet, as follows:
• Try to create a relaxed atmosphere at meal times and do not let them
  feel that you are upset or angry by their refusal to eat
• Continue to offer a variety of foods, including foodsthat they like
• Offer small portions rather than a very large plate of food
• Try to arrange their meals when they are hungry and try to ensure
that the family eats together as often as possible. If the child sees
everybody else eating the same food, they will probably be more willing to try it
• If possible, allow your child to help prepare the food

Certain foods are very important in the two to five age group. Carbohydrates such as bread, potatoes and cereals are important because they are a good source of energy.
Therefore, six or more servings from this group should be offered every day, with some included in every meal.

Fruit and vegetables are important sources of vitamins and minerals, and both are of similar nutritional value so if your child refuses to eat vegetables, offer more fruit instead. Four or more servings of fruit and vegetables are required each day and these can be cooked or raw. Frozen vegetables are just as good as fresh ones.

Meat, fish poultry, eggs and pulses are important sources of protein, which is essential for growth and development. The child in this age group should be offered two servings a day.

You should include snacks in your child’s daily diet as they will help to top up their high energy needs between meals. Try to make the snacks as healthy as possible, basing them on foods that they need such as carbohydrates and calcium-rich foods.

Suggestions include:
Cheese slices
Ham or tuna sandwich
Carrot or celery sticks

If you continue to be concerned about your child’s eating habits, visityour doctor or nutritionist/dietitian.

Which nutrients are particularly important for my child?
Calcium, which is essential for the proper development of bones, can be found in milk and other dairy products. However, the daily intake of milk should not exceed a pint, as large quantities of milk may reduce your child's appetite and prevent them from eating the required variety of food. Skimmed milk is not recommended before the age of five.

Cheese, milk and yoghurt can all be used in cooking without affecting the calcium content. These ingredients can be used as appropriate in dishes such as custard, toast with melted cheese on top or even pizza with melted cheese on top if you have difficulty getting your child to eat them otherwise. The child should be offered three servings a day.

Iron is essential for healthy blood and normal growth and development. Children have high iron requirements and should eat meat at least three to four times a week. Recently, however, approximately one in 10 two-year-olds in Ireland were found to be anaemic (not enough iron in the blood, which means that there is not enough oxygen being carried around their bodies to their cells).

The iron in meat is absorbed up to seven times faster than the iron from fruit, vegetables, nuts and cereals. However, meat eaten during the same meal as these foods will help the absorption of iron from them.

Therefore, a meal containing meat and vegetables is high in iron because the iron from the meat is easily absorbed and the meat also helps with the absorption of iron from the vegetables. Lean, red meat (beef, pork and lamb), chicken and fish are excellent sources of iron.

If your child is a vegetarian (or a vegan), consult a doctor or nutritionist/dietitian about their diet. If they do not eat meat, an alternative source of iron must be found.

Irish school children eat too much fat in their diet and a significant amount of this comes from eating high fat, energy dense snacks, according to the Irish Heart Foundation (IHF).

For this reason, the IHF in association with the National Heart Alliance, recommends the following:
• Breastfeed where possible, as children who have been breastfed have
  been shown to have lower blood cholesterol levels, lower levels of obesity
  and lower blood pressure values.
• A relatively high fat diet is important for children under the age of two.
  From two to five however, overall fat intake should be gradually reduced
  to around a third of total energy intake.
• Try not to add salt to food eaten by young people, as salt is directly related
  to the risk of developing high blood pressure, even in children.
• Snack foods are usually high in saturated fat, salt and sugar and should
  only be given to children as an occasional treat and not as part of a staple diet.
• Limit television watching, as food advertising has been shown to be a key
  influence on children's food choices.
• Encourage regular play and physical activity.

Why is good nutrition so important for teenage girls?
During their teenage years, girls gain more fat than boys and often take up excess dieting and smoking to help lose weight.

Calcium is an important mineral because girls gain as much as 90% of their bone density by the age of 17. However, Irish teenage girls have been found to avoid drinking milk, which can have a detrimental effect on their bone growth.

Milk, cheese and yoghurt are excellent sources of calcium and teenage girls and boys should take a pint-and-a-half of ordinary milk or a pint of fortified milk each day. This can be added to breakfast cereal, tea, coffee, cappuccinos, milkshakes and smoothies. Low fat and skimmed milk are also suitable for teenagers.

Iron is another important mineral, as almost a third of Irish teenage girls have been found to have low iron intake. The best source of iron is lean, red meat, which should be eaten two to three times a week, in the form of burgers, spaghetti bolognaise, lasagne, chops or shepherd’s pie. Alternative sources of iron include eggs, fortified breakfast cereal (check the label), wholemeal bread, broccoli, spinach, prunes, apricots and Bovril.

Iron is also found in vegetables but should be combined with food rich in vitamin C, for example orange juice (vitamin C) with beans (iron) on toast. Vitamin C increases the absorption of iron.

Citrus fruits (orange, lemon, lime and grapefruit), kiwi, nectarines, mango, blackcurrants and drinks based on these fruits are all rich in vitamin C. Potatoes are also a good source.

A vegetarian diet can be a healthy option and alternative sources of protein include cheese, yoghurt, milk, eggs, beans (all types, including kidney beans, butter beans, beans in tomato sauce), peas, chick peas, lentils, peanuts and hummus.

Why is good nutrition so important for teenage boys?
Between the ages of 13 and 17 most boys will gain around 17kg or 37lbs. That is quite a growth spurt in just four years and a lot of food is required to achieve this growth.

Teenage boys are known for their enormous appetites and they should aim to eat plenty of ‘white foods’, such as large helpings of bread, potatoes, rice or pasta in every meal. These starchy foods are energy giving foods, which are needed in large amounts to support the growth spurt of the teenage years. They also need one-and-a-half pints of milk every day, as well four or more servings of fruit and vegetables.

Snacking is fine as long as the snacks are healthy. Healthy snacks include a bowl of breakfast cereal (at any time), a sandwich, bread and peanut butter, toast, beans/spaghetti on toast, cheese strings, yoghurt, a yoghurt drink, a milkshake, a cereal bar, cheese and crackers, fruit, a fruit scone, rice cakes, oat cakes and bread sticks.

Why is good nutrition important in older people?
Ireland’s population is ageing and it is expected that by 2011, over 14% of the population will be over 65 years. For this reason, the need for optimum nutrition in this age group is becoming increasingly important.

What factors affect the dietary intake of older people?
Lack of education, income and adequate facilities to prepare food have been identified as predisposing factors in poor nutritional intake in the older independent person. Social isolation and loneliness are also factors, as are depression and dementia.

The principal cause of death in people aged 65 and over are diseases of the circulatory system, such as heart disease and stroke, along with cancer and pneumonia. Chronic diseases, such as cardiovascular and cerebrovascular disease, cancer, diabetes, constipation and osteoporosis, coupled with a lack of financial resources, insufficient food intake, and functional impairment place a substantial number of older Irish people at high risk of malnutrition.

Physical problems such as pain or the inability to feed themselves and psychological problems such as depression or a more serious psychiatric problem can also place the older person at risk of malnutrition, which includes both over- and under-nutrition. Untreated, these can have an impact on the health and well being of the older person, even resulting in early mortality.

However, simpler problems such as dentures that don’t fit properly or the fact that a person is simply ageing and their body processes are slowing down can also affect how much an older person eats. The use of a number of prescribed drugs may also interfere with the body’s absorption of the food eaten.

However, a balanced diet with plenty of fresh fruit and vegetables, and not too much fat can provide some protection against heart disease, stroke, some cancers, obesity and arthritis, which are conditions more commonly experienced by older people. While diet alone does not cause these diseases, along with environmental and genetic factors it is a contributory factor.

What are the main dietary guidelines for older people?
Older people should eat a wide variety of food, from a variety of food groups, following the Food Pyramid, in common with the recommended guidelines for adults in general.

Starchy food such as bread, potatoes, cereal, rice and pasta are good sources of sustainable energy and fibre and should be eaten throughout the day. Excessive consumption of sugar-rich foods should be avoided, however, as these provide energy ‘highs’ but no lasting energy.

Protein is also required for the growth and repair of body tissues, and is especially important in times of ill-health, when energy requirements rise.

Four or more fruit and vegetable portions are recommended for the older healthy person each day to achieve a good vitamin and fibre intake.

Meat, fish, poultry and dairy products such as cheese, milk and yoghurts should form part of a regular diet.

For healthy individuals, the consumption of a moderate intake of a mixture of fats is important but fat intake should be individually modified for those with acute or chronic illness.

A high fat intake is associated with high cholesterol levels, which is a risk factor for heart disease. Therefore, a diet with a moderate amount of so-called unsaturated fats (good fats) and low in saturated fats (bad fats) is recommended for older people. Oily fish is a good source of unsaturated fat.

Common problems in the elderly such as constipation and dehydration can be prevented by taking about 1.5 litres or eight cups of fluids every day. However, food intake should be balanced with exercise, which will burn up surplus calories and prevent obesity. Alcohol should also be consumed in moderation.

Where do I go for advice on nutrition?
Contact a dietitian or clinical nutritionist for safe, professional and personalised advice. The Irish Nutrition and Dietetic Institute will be able to let you know of a dietitian in your area.

The Institute can be contacted from Tuesday-Thursday, from 9am-12.30pm
at Tel: 01-280 4839.

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Welcome | A guide to nutrition | What Are functional foods? | Probiotics & your health
Obesity – an Irish epidemic | Nutrition & pregnancy | Your digestive system
The role of vitamins & minerals | Finland – a case study in healthy eating
Health Calculators