Nutrition in pregnancy

Statistics in every country differ but in general, people’s diet is not as good as we’d like it to be. Far too many women have poor intakes of folic acid and fail to meet nutrient intake levels for riboflavin, vitamin A, iodine, potassium, calcium, zinc, magnesium and iron. Consumption of fruit and vegetables is often far below the recommended 5 a day.

The consequences of poor maternal health are clear – reduced fertility, poor pregnancy outcomes and risk of congenital abnormalities and premature birth as well as low growth rate and birth-weight1. But it goes much further than that. Clinical studies now suggest that there is a link between the health of the mother before and during pregnancy and the likelihood of diseases in the next generation. The chances of suffering from glucose intolerance1, hypertension2 and cardiovascular disease3 in later life would seem to be linked to nutrition in the womb.

Healthy choices

It is important to improve the quality of the diet for women who are pregnant or planning to get pregnant rather than increasing the quantity eaten. During pregnancy, physiological changes mean nutrients are absorbed more efficiently and stores of both nutrients and fat are laid down but there is very little need for nutritional increase until the third trimester when energy requirements rise. Most women will only need to raise their energy intake by 200kcal.The following foods are good choices.
• Protein-rich foods like lean meat, chicken, fish, well-cooked eggs and pulses
• Five portions of fruit and vegetables each day – these can be fresh, frozen, tinned, dried or juiced • Pasta, bread, rice and potatoes – starchy food provides energy
• Wholegrain bread and cereal, pulses (like beans and lentils) – all containing plenty of fibre
• Fish (only two portions of oily fish per week due to possible build up of pollutants or toxins)
• Calcium-rich dairy foods like milk, cheese (not blue veined or mould-ripened cheese) and yoghurt
• Other vitamins and minerals will be provided from a balanced diet but expectant mothers should take 10 mg of vitamin D supplement daily
• Green vegetables and brown rice – contains Folate

• 400 mg of folic acid daily until the 12^th week of pregnancy. This helps to reduce the risk of neural tube defects in the developing baby

Foods to be careful of

The following foods should be avoided.
• There is a possible risk of listeria from the following – undercooked eggs or meat, pate, liver and liver products, unpasteurised dairy products and blue veined or mould ripened soft cheese

• Supplements or foods containing high amounts of vitamin A
• Raw shellfish may contain parasites and shark, swordfish and marlin are high in mercury Other things that should only be taken in moderation:

• Foods high in fat or sugar should be limited

• Foods containing caffeine, like tea, coffee, cola or chocolate should be limited to 200mg per day. Guidelines to caffeine content are: percolated coffee, mug – 140mg instant coffee, mug – 100mg tea, mug = 75mg plain chocolate, 50mg bar – 50mg cola, can – 40mg
• Limit tuna to 2 fresh steaks or 4 medium size tins per week
• Alcohol can be harmful to the foetus. Intake of more than 5 units per day can lead to poor growth and development. Avoid alcohol for the first 3 months of pregnancy and limit thereafter to 1-2 units no more than once or twice a week

In 2008, the possible problems of eating nuts during pregnancy was a widespread topic in the press. Since then the Food Standards Agency in the UK has stated that only mums to be, their partners or siblings of the baby who have a history of allergy MAY wish to avoid peanuts or peanut products during their pregnancy to reduce the risk of baby developing an allergy.

Necessary inclusions

There are some nutrients that pregnant mothers need particularly.

FOLIC ACID
Some authorities recommend that women who may become pregnant should take 400 mg of folic acid from 3-6 months before becoming pregnant till the 12th week of pregnancy. This is as well as making sure that 200 mg per day is provided by diet. Good dietary sources include brown rice, oranges, fortified breakfast cereal, peas and broccoli. Folic acid is important for cell division and lack of it can lead to spina bifida.

OMEGA 3 AND OMEGA 6 FATS

Some important nutrients like Omega 3 & 6 need to be provided from diet as they are not easily made by the body. These ‘good fats’ are particularly needed during the last trimester of pregnancy. They are vital for the growth and development of baby’s brain and can be found in oily fish like trout, pilchards, kippers, mackerel, sardines and tuna.

CALCIUM

Absorption is increased during pregnancy and expectant mothers need 500-700mg daily. A half litre of milk (skimmed, semi-skimmed or whole) will provide 600mg of calcium. Dairy products are a good source but canned fish, green vegetables, hard water, pulses and bread also provide calcium.

VITAMINS
Good sources of vitamin D include fortified breakfast cereals, margarine, oily fish and meat. Women who do not get very much sunlight, have a BMI over 30 or are of Asian origin may be at risk. All pregnant women should take a daily supplement of 10 mg of vitamin D per day.

During pregnancy, requirements for vitamin A increase by 100 mg per day to 700 mg. Good dietary sources are eggs, oily fish, milk and cheese but daily amounts should not be exceeded as this can be harmful to the baby.

IRON
Recommended levels for pregnant women are 14.8mg per day. Iron deficiency is a common problem as many women do not achieve this and if ferritin or Hb levels are low at the beginning of pregnancy then an iron supplement should be prescribed. They should also be encouraged to eat iron rich foods and those high in vitamin C to help with iron absorption.

Many foods contain iron but it is more easily absorbed from some than from others. Foods with iron less easily absorbed include bread, products containing dried fruit, cereal, beans, lentils, nuts, egg yolk and ginger cake & biscuits. It is more easily absorbed from meats like turkey, chicken, lamb, beef, burger and sausages.

References

1. Balci MM, et al. Low birth weight and increased cardiovascular risk: Fetal programming. International Journal of Cardiology 2008. In press

2. Maternal nutrition, fetal nutrition and disease in later life. Nutrition 1997 13 (9) 807-13

3. Flanagan DE et al. Fetal growth and the physiological control of glucose tolerance in adults: a minimal model analysis Am J Endocrinol Metab 2000 278 (4) E700-E706