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What exactly is a healthy diet?Foods and fertility are linked. If you and your partner stick to a healthy, balanced diet, you may be able to boost your chances of conceiving (Homan 2007).
So, what is a healthy diet? A healthy diet simply means eating a balanced variety of foods. Try to include the following:
- At least five portions a day of fruit and vegetables, whether fresh, frozen, canned or dried. Two broccoli spears and one medium glass of orange juice are each one portion.
- Plenty of starchy foods, such as bread, pasta, cereals, protein and rice. Try to have one portion with each meal. If you can, choose wholegrain varieties, which contain more fibre.
- Some protein, such as lean meat and poultry, fish, eggs and pulses (beans and lentils). Aim for two portions a day, or three if you are vegetarian.
- Fish should make up about two portions a week. One of these should be oily, but try to have no more than two portions of oily fish a week (COT 2004, FSA 2004).
- Some low-fat dairy foods, which contain calcium. Aim for three portions a day, one portion being a yoghurt or a glass of semi-skimmed milk (NHS 2010).
- Some iron-rich foods, such as red meat, pulses, dried fruit, bread, green vegetables and fortified breakfast cereals. These build up your resources of iron in preparation for pregnancy.
Try to have something containing vitamin C, such as a glass of fruit juice, with iron-rich meals. This can help you to absorb iron from non-meat sources.
Make cakes, pastries, fizzy drinks and some takeaway and fast foods an occasional treat. These tend to be high in fat, sugar and salt. They may fill you up, but they aren't usually nutritious.
The government's eatwell plate is a useful visual guide to the proportion of each food group that should make up your daily diet.
If you're wondering when you should start to improve your diet, there's no time like the present. A healthy diet is important both before and during pregnancy.
What about my weight?Try to get as close as possible to your recommended weight before trying for a baby. Ideally, your body mass index (BMI) should be between 18.5 and 25 (Barrowclough 2009, BNF 2006).
Being overweight or underweight can reduce your chances of conceiving (NCCWCH 2013:71, Homan et al 2007, Nice 2010, SIGN 2010), because you may ovulate less often. But there are other good reasons for getting to a healthy weight before you begin trying for a baby.
Being underweight before conceiving is linked to an increased risk of having a baby with a low birth weight or who is small-for-dates (Barrowclough 2009). Your GP may refer you to a dietitian who will be able to advise you about the best ways to gain weight.
Being overweight before conceiving has been linked to increased risk of complications once you're pregnant. Dieting during pregnancy is not recommended, so now's a great time to start making healthy eating choices that you can stick to once you do conceive (Williamson 2006). Talk to your GP if you need advice about changing your diet or starting exercise. Aim to lose no more than between 0.5kg (1lb) and 1kg (2lb) a week (NICE 2010).
Exercise is important, too. If you build it into your daily routine, perhaps walking briskly to work, getting off the bus one stop earlier, or taking the stairs (NICE 2010), it will be more achievable.
Joining a group can help you to stay motivated to lose weight and keep it off. You'll be offered regular advice on exercise and diet, as well as support from others (NCCWCH 2013:71).
Extreme weight loss from crash-dieting can deplete your body's nutritional stores. Losing weight gradually, and through healthy eating and regular exercise, is the best option. Long-term lifestyle changes are more successful than quick-fix approaches (SIGN 2010: 73).
If you are overweight and are trying to eat more healthily:
- Make time for breakfast every day. You're less likely to snack on unhealthy foods later if you had a bowl of porridge first thing.
- Keep an eye on your portion sizes at mealtimes. Eat from a smaller plate if it helps.
- Have healthy snacks to hand, such as a handful of fresh or dried fruit. That way you won't succumb to high-sugar, high-fat options when you're out or at work (NICE 2010).
Do I need a vitamin supplement?Vitamin supplements are not a substitute for eating well, but may help if you're finding it hard to have a varied diet.
However, there is one daily supplement you should certainly take as soon as you stop using contraception until you're 12 weeks pregnant (NCCWCH 2013:69, CKS 2007), and that's folic acid.
Folic acid protects an unborn baby against the risk of spina bifida and other neural tube birth defects (Blencoe et al 2010).
You'll need a daily supplement of 400 micrograms (mcg) of folic acid (NCCWCH 2013:69, CKS 2007). If you're taking a multivitamin supplement that already contains 400mcg of folic acid, you won't need a separate folic acid supplement. Check the packet or ask your pharmacist if you are unsure.
You should take a higher daily dose (5mg) of folic acid if (NCCWCH 2013:76):
- you have had a child with a neural tube defect, such as spina bifida
- you or your partner or immediate relative has a neural tube defect (CKS 2007)
- you are taking anti-epileptic drugs
- you have coeliac disease (autoimmune condition triggered by gluten)
- you have sickle cell disease (CKS 2007)
- you have thalassaemia
- your BMI is higher than 30
- you have diabetes
See your doctor if any of these apply to you, as you'll need a prescription for a 5mg dose.
As well as taking a folic acid supplement, eat plenty of foods rich in the naturally occurring form of folic acid, called folate. Foods rich in folate include dark green leafy vegetables such as spinach, kale, citrus fruits, nuts, brown rice, fortified bread and some fortified breakfast cereals.
You may also want to take a 10mcg daily supplement of vitamin D. Some women have low levels of this due to their skin colour or where they live in the UK (BNF, 2006). If you're taking an antenatal multivitamin, vitamin D may be included, so check the label.
Some over-the-counter supplements may contain large doses of vitamins and minerals which could be harmful to a developing baby. Only take a vitamin supplement tailored to women who are trying to conceive or who are pregnant. The supplement should not contain the retinol form of vitamin A or fish liver oil.
Find out if you are eligible for the government's healthy start vitamin vouchers at www.healthystart.nhs.uk.
Should I cut back on alcohol yet?Although there is evidence that heavy drinking can affect semen quality, experts are not sure whether alcohol affects female fertility (NCCWCH 2013). However, heavy or binge drinking can be harmful to a developing baby (NCCWCH 2013:69). The government therefore recommends that women should stop drinking alcohol when trying for a baby (DH 2009).
If you do choose to drink, have no more than one or two units of alcohol once or twice a week (NCCWCH 2013:69, CKS 2007).
A unit is half a pint of standard-strength beer, lager or cider, or a pub measure of spirit. But keep in mind that many beers and ciders are stronger than this. A small glass of wine is about 1.5 units and alcopops are about 1.5 units (FSA nd: a).
If cutting down is proving difficult for you, ask your doctor for advice (CKS 2007).
Will caffeine make it harder for me to conceive?There's no clear evidence that caffeine causes fertility problems if you are trying for a baby naturally (NCCWCH 2013:70), but it could affect your chance of success if you are having IVF (NCCWCH 2013:228).
Bear in mind that the government advises pregnant women to limit their intake of caffeine. If you have a caffeine habit, it could be worth weaning yourself off it now.
So, how much is too much? 200mg of caffeine is roughly equivalent to:
- two mugs of instant coffee (100mg each)
- two cups of filter coffee (100mg each)
- four cups of tea (50mg each)
- five cans of cola (up to 40mg each)
- four (50g) bars of plain chocolate (up to 50mg each), though bars of milk chocolate contain less (25mg each) (FSA 2008)
- 10 cups of green tea (20 mg each)
The caffeine content of espressos, and coffees based on espressos, such as cappuccinos and lattes, can depend on the outlet. One study found that caffeine levels can range from 50mg per espresso at one chain to as much as 300mg per espresso in another (Crozier 2010).
Some cold and flu remedies also contain caffeine. Always check the label, and ask your pharmacist if you're not sure (NHS 2010).
Is there anything I need to be careful about eating or drinking?Don't eat foods which are high in the retinol form of vitamin A, such as liver and liver products, including pate. The vegetable form of vitamin A, betacarotene, is fine.
Some supplements contain retinol because they use fish liver oil, so these should also be avoided. Too much retinol in your body once you're pregnant could harm your baby (Barrowclough 2009, CKS 2007).
Don't eat fish shark, swordfish or marlin. These fish can contain mercury.
Eat no more than two portions a week of oily fish a week. Oily fish include mackerel, sardines, salmon, trout, fresh tuna, pilchards, kippers and herring. The reason for the two-portion limit is that oily fish may contain pollutants, such as dioxins and PCBs (polychlorinated biphenyls). These build up in your body over a long period.
Soft, mould-ripened, or blue-veined cheese such as brie, camembert or Danish blue, are off limits too. Along with pate, eating these may increase your risk of developing listeriosis (Barrowclough 2009).
Talk to others who are hoping to get pregnant by joining our Actively trying group.
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