Vitamins and Minerals
Calcium and Bone Health
Flour, particularly white flour, is rich in calcium, essential for strong, healthy bones and teeth. Six slices of white bread every day will provide around 20% of the recommended daily calcium intake. Bread is one of the best sources of calcium in our diet.
Calcium, the most abundant mineral in the body, is vital to the structural integrity of the bones and teeth. It also has a role in metabolic processes within the body. A lack of dietary calcium can lead to osteoporosis in which the bones become porous. Osteoporosis usually affects the whole skeleton, but it is most commonly causes breaks (fractures) to hones in the wrist, spine and hip. After the age of 35 years bone loss can increase as part of the natural aging process. It is extremely important that women at risk eat a calcium rich diet, take plenty of exercise and also make sure they are eating enough vitamin D (assists in the absorption of calcium into the bone).
The fortification of flour contributes to 14% of the total
calcium intake and in the absence of this fortification it would be
assumed that these intakes would fall below the recommended
nutrient intake (RNI). The current RNI for calcium is 600mg a day
for children and 1000mg a day for an adult.
|Top calcium providers||Amount of calcium in mg / per 100g of food|
Iron Status and Bread Consumption
Flour is one of the main sources of iron in the diet, which is an important mineral, essential for healthy blood cells and good circulation. Bread is an excellent source of iron. The major source of iron in the UK is from cereals including wheat flour and other cereal based products which together provide almost 50% of the daily iron intake. Intakes from iron have been declining for some time and there is particular concern that nearly 25% of women have dietary intakes below the Reference Nutrient Intake (RNI). The clinical affects of iron deficiency include general lethargy and anaemia and if untreated can result in severe long-term effects on mental and physical status and development. The current RNI for iron is 14.8 mg/day for women and around 10 mg/day for men.
|Top iron providers||Amount of iron in mg / per 100g of food|
|White bread||1.6 mg|
|Brown bread||3.2 mg|
|Wholemeal bread||3.5 mg|
|Peanut butter||2.0 mg|
|Dried apricots||3.4 mg|
|Kidney beans||6.4 mg|
B vitamins thiamin and niacin help the body release energy from
carbohydrate and help ensure the skin, eyes and nervous system
remain healthy. Over a third of our daily requirement of thiamin
comes from cereals and flour-based foods such as bread. Bread is
also a good source of niacin, another B vitamin.
Folic acid is present in wholemeal flour and added at higher
levels to some breads. More general fortification in other flour is
presently under consultation by an expert committee advising the
Department of Health. Folic acid helps protect against neural tube
defect in unborn babies and is an essential nutrient for pregnant
Selenium is a trace element found widely in the environment. According to the Food Standards Agency (FSA) good sources include brazil nuts, bread, fish, meat and eggs. Selenium is present in fish (0.32mg/kg), offal (0.42mg/kg), brazil nuts (0.25mg/kg), eggs (0.16mg/kg), bread (0.053mg/kg) and other cereals (0.02mg/kg). The UK reference nutrient intake (RNI) for selenium is 0.075mg a day for men and 0.06mg a day for women (COMA values). You should be able to get all the selenium you need from your daily diet.
Selenium is an essential trace element, which is necessary for the functioning of the enzyme glutathione peroxidase, which protects against intracellular oxidative damage. In essence selenium functions as an anti-oxidant and can help protect the body from oxidative damage caused by stress, pollution and aging. Selenium has been claimed to reduce the incidence of a range of cancers, although the COMA report on Nutritional Aspects the Development of Cancers (1998) considered there to insufficient evidence for such a link. Research in this area continues.
The selenium concentration of plants is determined by the content and availability of the element in the soil in which they are grown. The selenium content of plant foods therefore varies from country to country.
Concerns have been raised that selenium intakes in the UK are
falling. In previous years the UK milling industry used more wheat
sourced from North America. North American wheat contains slightly
higher levels of selenium than UK wheat. However UK wheat still
contains more selenium than European grown wheat. Since the UK now
uses mostly homegrown wheat - this is reflected by slightly lower
levels of selenium than US wheat. The trend towards using UK rather
than North American wheat coupled with the fact that there has been
a decline in the consumption of cereals and wheat based foods such
as bread (both good sources of dietary selenium) would result in
slightly lower intakes of selenium in the UK.
Fibre - wheat is an excellent source of fibre and wholemeal flour, which contains the whole grain including the bran and germ. Brown and white flour also contain fibre. For a healthy, balanced digestive system it is important that we eat enough fibre. All bread contains a significant amount of dietary fibre, although wholemeal bread contains three times as much as white bread.
Protein - flour is a good source of protein and is low fat, unlike some sources of animal proteins. Protein is essential for growth, maintenance and repair of the body.
Carbohydrates - the majority of carbohydrates
in flour are complex carbohydrates that we all need to give us
energy. We need to eat more complex carbohydrate - rich foods to
replace some of the fat in our diets, for example nutritionists
recommend we eat six slices of bread a day. According to the
British Nutrition Foundation's Balance of Good Health, we should be
eating 50% of our energy intake as carbohydrates.
Flour is a natural and wholesome food. By law, white and
brown flour is fortified with calcium, iron, thiamin and niacin
(see table below). Because it is made from the whole wheat grain,
wholemeal flour already contains these vitamins and minerals,
although white and brown flour contain more calcium because of
Calcium carbonate (E170) is added to all brown and white flour products in the UK and has been a legal requirement for almost 5 years. This is carried out to ensure that vulnerable groups receive enough calcium in their diet. On average 20% of the UK dietary calcium intake is accounted for via bread and flour products. Other legally required additives in bread include iron and B-Vitamins.
The following table shows the nutritional value of an average selection of flours:
|g/100g except where stated||Strong White||Plain White||Brown||Wholemeal|
|Extraction Rate % (approx)||75||75||85||100|
|Protein % variable depending on whether strong or weak flour||11.5||9.4||12.6||12.7|
McCance & Widdowson (6th Edition)
The nutritional composition of white, brown and wholemeal bread is compared in the table below:
|(of which sugars) %||2.6||3.0||1.8|
|Dietary Fibre %||2.3||4.7||7.1|