O level Notes : Food Technology Design - Meal Planning And Food Service - Nutritional requirements for pregnant women

During pregnancy there is an increased requirement of HBV protein, folate, iron, vitamin B12  and iodine. Recommendations include:

• Expectant mothers must be served balanced meals at the right time and all meals must be taken. No 'crash dieting', as this can have a negative impact on the baby.
• The diet should provide sufficient high biological value protein to cater for growth of the foetus.
• Extra energy is required for the adjustment of the mother's body to pregnancy.

But remember no 'eating for two', as this will lead to unnecessary weight gain. A healthy pregnancy only requires about an extra 1,400 to 1,900 kilojoules a day during the second and third trimester, which is equivalent to a glass of milk or a sandwich.

• Reduce sugar intake as well since pregnant women are less active.
• Iron is required for oxygen transport in the body. Iron is also essential as the foetus needs to have an iron store to use during the first few months after birth and to prevent anaemia in mother. Serve iron rich foods with foods rich in vitamin C to help increase iron absorption. Iron supplements can be advised by the doctor during pregnancy.
• Folate or folic acid is important, three months before and in the first trimester of pregnancy for proper development of the baby and for prevention of neural tube defects. All women of childbearing age should eat high-folate foods (such as green leafy vegetables, fruits and legumes).
• Iodine is important for normal growth and development of the baby. Iodine supplements are often advised during pregnancy to meet the increased needs, as food sources (such as seafood, iodised salt and bread) are unlikely to provide enough iodine.
• Reduce fat intake as this is difficult to digest.
• Calcium and phosphorus is required for building bones.

Nutritional requirements for breastfeeding mothers

During lactation, there is an increased requirement for energy, protein, all the vitamins (except B6), calcium, phosphorus, magnesium, zinc, folate, iodine, copper and selenium.

• Nursing mothers require more than normal protein for milk production during breast feeding (lactation.)
• Breastfeeding burns through extra kilojoules. Extra energy is required for the production of milk and some of this is laid down as fat during pregnancy.
• Vegan mothers who are breastfeeding (and during pregnancy) should take a vitamin B12 supplement.
• Eat and drink regularly – breastfeeding may increase the risk of dehydration and cause constipation. Fluid needs are approximately 750 – 1000 ml a day above basic needs.

Nutritional requirements for invalids and convalescents

An invalid is a person who is sick. A convalescent is one who is no longer sick but in the process of gradual recovery after illness.

Nutritional requirements vary depending on whether someone is healthy or ill. As diseases are unique so are the nutritional requirements needed whilst the person is ill. For example, when planning a meal for someone recovering from a fracture, more calcium is needed to heal the fracture whilst more iron is required by someone who has been diagnosed with anaemia. The following recommendations might be useful in ensuring a balanced diet for the sick and those recovering:

• Doctor's recommendations must be adhered to as some foods may need to be avoided.
• Protein is needed to build or repair body tissues.
• Low energy diet is recommended since they are less active. Too much fat and carbohydrates may lead to obesity and coronary heart diseases. Make use of lean meats, fish, liver, low-fat dairy foods, nuts and seeds, legumes, fruit and vegetables, wholegrain breads and cereals and limit cakes, sweet biscuits and soft drinks.
• Diet must be low in fat because it is difficult to digest and it is also a concentrated supply of energy.Avoid fried foods and oily foods.

• Iron is needed to replace blood lost. To ensure proper absorption of iron serve iron rich foods with foods rich in vitamin C.
• Calcium is needed after a fracture to repair the damaged bone.
• Vitamin C helps in healing and prevents bed sores.
• Water prevents dehydration from fever, vomiting and diarrhoea.

Nutritional requirements according to level of activity

It is important to note that carbohydrate intake is determined by the body size and level of activity. Therefore, when planning meals, it is important to match the energy output to the individual's energy expenditure because people who take more carbohydrates than they require become over weight and eventually become obese. A manual worker has a different carbohydrate requirement to that of a sedentary worker. Heavy work and Exercise increase metabolic efficiency in some people and increase their nutritional requirement.

Manual labourers

These are people who do physical work. Manual workers include railway workers, postmen and women, joiners, bus conductors, farm workers, miners, steel workers, forestry workers, and army recruits.

Poor diets and bad nutrition can have a detrimental effect on manual workers affecting their morale, safety, productivity and long term health. It is important that they keep their energy level high for the day to enable them to complete work and being alert so as to prevent accidents. The following recommendations must be taken into consideration to ensure adequate supply of carbohydrates:

• When the body needs energy to perform hard working it turns to calories for fuel. Carbohydrates should be the main source of energy and should make up the largest percentage of the daily calorie intake. Make use of excellent sources of carbohydrates such as whole grains, whole grain pasta and legumes.
• Ensure sufficient protein for strengthening, maintenance and growth of muscle fibre.
• Iron is needed for carrying oxygen, oxidize glucose and help in release of energy.
• Vitamin B is needed for the release of energy from carbohydrates, fats and proteins.

Sedentary workers

Sedentary can be described as behaviours that involve sitting or reclining, resulting in little or no physical activity. Sedentary workers include office workers, pilots' drivers, teachers, journalists, doctors, lawyers, architects, shop owners. Their jobs involve very limited amounts of physical activity.  Prolonged sitting pose significant risks to the health of workers. Heart disease, blood clots, obesity and cancer are all associated with sedentary lifestyle. Recommendations are:

• Lower the energy intake by choosing a balanced diet which uses low-fat, high- fibre foods.
• Plan a varied balanced diet. Select foods from all the food groups on a daily basis:

-     Fruit and vegetables.

-     Whole, unsifted, high fibre grains and cereals.

-     Legumes (dry beans, peas and lentils)

-     Lean meat, fish or eggs.

-     Mono- or polyunsaturated margarine and oils.

• Avoid fat-loaded snacks and foods that contain a concentrated supply of energy.
• Regular Exercise combined with low-fat and high-fibre diet will help reduce