This chapter considers the role and importance of vitamins and minerals, defining their function in healthier nutrition and outlining a range of food sources for these essential components to life. (This is quite a long chapter, but it is important you understand the role of the most important micronutrients).
Micronutrients - Vitamins and minerals
These are required in minute quantities which is why they are called micronutrients while protein, fat and carbohydrate are called macronutrients as they are needed in greater quantities. Vitamins and minerals are essential for health but do not provide any energy.
NHS Choices provides useful information on vitamins and minerals (see useful links).
There are two groups of vitamins and the type of vitamin determines whether they are stored or not.
Fat soluble vitamins are vitamin A, D, E and K. Fat soluble vitamins can be stored in the body usually in the liver and are absorbed into the body along with fatty foods.
Water soluble ones are vitamin C and the B vitamin group. This group of vitamins is needed to be eaten regularly in the diet as they cannot be stored. Any excess of the water soluble vitamins is excreted in the urine. This group is also easily destroyed in cooking.
Vitamin C is an antioxidant which means it has a protective effect in the body and helps to protect against diseases like coronary heart disease and cancers. (Antioxidants are also beta carotene and the mineral selenium but there are also other protective antioxidants found particularly in fruit and vegetables).
Vitamin C helps the body to absorb iron from foods so is particularly important in diets which do not contain red meat, which contains iron. Vitamin C also has a role in enhancing the immune system and promoting the healing of wounds.
Collagen is the tissue framework that connects and holds cells together in all of the tissues of the body such as the muscles and heart and lungs. Vitamin C helps to maintain the connective tissue in the body.
Sources of vitamin C are fruit and vegetables especially citrus fruits like oranges and soft fruits like strawberries and blackberries and tropical fruit like passion fruit and kiwi fruit. Fruit juices also contain vitamin C. Many vegetables contain vitamin C such as green vegetables like peas, runner beans, cabbage and broccoli, salad vegetables such as lettuce also provide vitamin C.
Potatoes also provide vitamin C particularly if served with skins on.
Cooking vegetables (and fruit) quickly with a minimum amount of water (or steaming them) and also serving them immediately helps to retain the vitamin C plus B vitamins.
When fruit and vegetables are frozen, the vitamin C (and B vitamins) are retained so these can be a useful standby for caterers especially in the winter months when fresh vegetables can be both expensive and scarce.
B Vitamin Group
The B vitamins are a group of vitamins which help the body to release energy from food as well as having functions with the nervous system and also blood cell formation.
Examples of B vitamins are Thiamin, Riboflavin, Niacin and Vitamin B6.
B vitamins are found in a wide variety of different foods including meat, milk, eggs, cereals and bread. Yeast extract is a particularly good source. B vitamins are also added to fortified breakfast cereals.
Examples of other important B vitamins are Folate/Folic acid. Folate is the natural form of the vitamin found in food and folic acid is the manufactured form. This vitamin is particularly important in pregnant women as it helps to prevent conditions such as spina bifida.
All women who are pregnant are recommended to take a supplement of folic acid for the first 12 weeks of pregnancy. Also those who wish to become pregnant are also advised to take a supplement. Sources in the diet are green leafy vegetables like cabbage and broccoli, wholegrain bread and fortified breakfast cereals.
NHS Choices has useful information on Vitamin B (see useful links).
Vitamin B12 is another B vitamin and is needed for the formation of red blood cells. As it is found mainly in foods from animals like meat, milk, fish and eggs, vegans (who obviously do not take any of these foods) can lack the vitamin. Vegans can take yeast extracts and fortified breakfast cereals to provide vitamin B12. Lack of vitamin B12 can cause a form of anaemia.
Vitamin A is one of the fat soluble vitamins and required for healthy eyesight, and the immune function. Vitamin A is found in foods which contain fat like butter and margarine, oily fish, eggs, liver, full-fat milk products like hard cheese.
While liver is a good source of vitamin A it is not recommended during pregnancy as too much vitamin A can be harmful to the growing foetus.
The body can also make vitamin A from beta carotene. Beta carotene acts as an antioxidant and thus helps to prevent diseases like coronary heart disease. It is the orange red colour in fruit and vegetables like apricots, carrots, tomatoes, mangos, sweet potatoes and also in dark green vegetables like broccoli and spinach.
Vitamin D is needed to enable the absorption of calcium from foods. As calcium is needed for strong bones and to prevent conditions like rickets in children where the bones in the legs become softened and deformed. The adult condition like rickets is called osteomalacia.
Vitamin D is made by the action of sunlight on the skin during the summer months in the UK. Anyone who does not go out of doors, such as the housebound or those who cover themselves up with clothes, may not make sufficient Vitamin D in the skin. Therefore these groups may lack this vitamin.
Vitamin D is found in foods such as butter, margarine, liver, oily fish, salmon, egg yolk and red meat.
The Department of Health recommends all pregnant and breastfeeding women should take a daily supplement containing 10 micrograms (0.01mg) of vitamin D to ensure the mother's requirements for vitamin D are met and to build adequate foetal stores for early infancy.
All babies and young children aged six months to five years should take a daily supplement containing vitamin D in the form of vitamin drops to help them meet the requirement set for this age group of 7-8.5 micrograms (0.007-0.0085mg) of vitamin D a day.
Babies fed infant formula will not need vitamin drops until they are receiving less than 500ml (about a pint) of infant formula a day, as these products are fortified with vitamin D.
Breastfed infants may need to receive drops containing vitamin D from one month of age if their mother has not taken vitamin D supplements throughout pregnancy.
People aged 65 years and over and people not exposed to much sun should also take a daily supplement containing 10 micrograms (0.01mg) of vitamin D.
NHS Choices has useful information on vitamin D and other vitamins and minerals (see useful links).
This is a group of micronutrients which is needed in the body as part of structures and also for other functions.
Iron is needed for the formation of haemoglobin which is found in the red blood cells and carries oxygen from the lungs to all cells of the body. If people do not take enough iron in the diet a lack causes iron deficiency anaemia. This has symptoms of tiredness, lethargy, breathlessness and poor wound healing. Some groups are at particular risk and this includes older people, toddlers, those who do not eat meat and women of childbearing age are particularly at risk.
Women need more iron than men due to the monthly blood loss during the childbearing years.
Food sources of iron include liver, red meat like beef, lamb and pork, dark coloured fish like salmon, there is some iron in eggs, chicken, poultry, pulses, bread, dark green vegetables and dried fruit.
Meat and offal contain iron in the haem form which is easily absorbed while that iron from vegetables and cereals is poorly absorbed. As discussed vitamin C aids absorption of iron.
Calcium is needed for bone health and as already described vitamin D is needed for the absorption from foods. The hard substance in bones is called calcium phosphate. The calcium in bones is being gradually replaced over time.
Calcium is also needed in children for the development of teeth. Most of the skeleton develops during the teenage years so adequate calcium during this period is particularly important.
Calcium is also required for the growth of the foetus during pregnancy plus the production of breast milk after the birth of the baby.
Lack of calcium contributes to rickets in children and bone problems like osteomalacia in adults. Osteomalacia is a condition where the bones become brittle and weakened and people can easily suffer a fracture when they fall. The condition particularly affects older women.
Sources of calcium are milk and products made from it like cheese and yoghurt. Fish like salmon and pilchards where the small bones are eaten provides calcium. Calcium is also found in some breads and cereals as well as dark green vegetables.
The National Osteoporosis Society has helpful information on calcium and vitamin D (see useful links).
Zinc is needed for fertility and the immune system which helps with the resistance to infections. Zinc also helps with healing and taste sensitivity. Zinc is particularly required during the teenage years for the development of fertility. Men need more zinc than women as it is required to produce sperm.
Zinc is found in liver, red meat like beef, pork and lamb, fish like salmon, eggs, chicken, turkey, pulses and nuts.
Sodium and potassium
Sodium and potassium are both known as electrolytes and are called this as they can carry minute electrical charges. As electrolytes both sodium and potassium are needed for the nervous system and also for the muscles to function properly by contracting and relaxing.
The electrolytes are also required for maintaining the fluid balance in the body.
Too much sodium (and hence salt which is correctly called sodium chloride) is associated with high blood pressure (hypertension). High blood pressure is linked with coronary heart disease and also strokes. Adults are recommended not to eat more than 6 g of salt per day. Children require less salt.
Sodium is found in table salt (sodium chloride) and foods which contain it which are usually processed foods such as ready meals, cheese, savoury snacks such as potato crisps, sausages, ham and bacon.
Potassium is found in fruit, particularly bananas. It is also found in fruit juices, vegetables and potatoes and coffee.
Do you know what else is in your food?
Along with the aforementioned carbohydrates, fats, proteins, vitamins and minerals, your food is also made up of water, fibre and some things that might not always be so apparent, including food additives.
Food additives must be assessed for safety before they can be used in food. European Union (EU) legislation requires most additives used in foods to be labelled clearly in the list of ingredients, with their function, followed by either their name or E number. An E number means that it has passed safety tests and has been approved for use here and in the rest of the EU.
The Food Standards Agency (FSA) also ensures that the science on additives is strictly reviewed, the law strictly enforced, and action is taken where problems are found. They investigate any information that casts reasonable doubt on the safety of an additive.
Menu Ideas - Fruit & Vegetables and Milk & Dairy Foods
Encourage people to eat at least 5 portions of fruit and vegetables by having fresh fruit on the menu as whole fresh pieces, fruit platters or fruit salads. Stewed or baked fruit is a welcome alternative for people during winter months; include puddings like crumbles, charlottes and terrines on the menu as well as cakes which contain fruit like apple cake.
Vegetables can also be used in cakes and tray bakes such as chocolate beetroot cake and courgette cake.
Breads can also be made with vegetables and fruits as ingredients.
Add extra vegetables to curries, casseroles and other dishes. Lentils can be used for thickening curries and casseroles and this increases the amount of protein and fibre while lowering the amount of fat.
Make sure there are a good variety of vegetables for customers to select from. As we have already discovered, portion sizes of vegetables should be 80g. Frozen vegetables offer a beneficial amount of water soluble vitamins and make an easy and economical standby.
Remember to preserve the vitamins in vegetables by cooking quickly (preferably by steaming) and then serving straight away. Avoid overcooking.
A range of salads should be provided so that there is a variety. Also provide some salad without dressing so customers can add their own.
Soups which are homemade and based on vegetables of all types are both easy to make and provide a portion of vegetables.
Smoothies based on fruit can be attractive to customers and homemade easily.
As already mentioned, it is good to offer a range of milks for beverages.
Sauces and custards can be made with skimmed milk to reduce fat.
A range of yoghurts can be offered and indeed yoghurts can be made in the kitchen.
Various cheeses including lower fat ones can be provided so customers can choose a lower fat variety.
Milk puddings like rice pudding and blancmange can be comforting and enjoyable puddings.
The world Cancer Research fund has helpful information on fruit and vegetables on their website. (See Links & Resources at the end of this chapter).
By the end of this chapter you should have developed the following understanding and insights:
- An understanding of the role vitamins and minerals play in the function of the human body
- An understanding of the function of various vital vitamin groups
- An understanding of the function of various vital mineral groups
- An awareness of menu considerations for inclusion of vitamins and minerals