Pregnancy and dieting usually aren’t two words you hear together. But  for some women dieting may be necessary for a healthy pregnancy. The British Medical Journal (BMJ) reports that serious complications, such as pre-eclampsia, diabetes and premature birth can be safely reduced in overweight and obese pregnant women by following a healthy, calorie-controlled diet during pregnancy. 

What’s considered normal weight gain for a pregnant woman?

According to the Institute of Medicine, a woman whose body mass index (BMI) is between 18.5 and  24.9 should gain from  25 to 35 pounds (11.4-15.9 kilograms) during the nine months. A woman who is overweight at the start of pregnancy should gain between 15 to 25 pounds (6.8 to 11.4 kg).

A baby typically weighs between seven and nine pounds – where does the other weight go?

Your own body must add blood, fluids and tissue and store nutrients. Remember – you’re creating another human! A good percentage of fat is stored to provide additional calories for nursing (approximately seven pounds), and another 10 pounds is spread among the placenta, blood, breasts, amniotic fluid and body fluids.

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Could dieting during pregnancy be harmful?

Yes. Pregnancy certainly shouldn’t be the time in a woman’s life where she is overly concerned about weight gain. However, if the expecting mother already is overweight or obese – or if she gains more than what her doctor recommends – pregnancy can be a good time to talk about weight management because women generally become more motivated to make healthy changes for their baby’s sake. Currently,  over half of the UK's female population of reproductive ages is overweight or obese, and up to 40 percent of European and American women gain more than the recommended weight in pregnancy.

Research leader, Dr Shakila Thangaratinam from Queen Mary's University of London found that weight management interventions during pregnancy proved effective in reducing the mother's weight gain, and that diets achieved the largest average weight loss of almost 8.8 lbs (4 kg) in comparison with only 1.5 lbs (0.7 kg) for exercise and 2.2 lbs (1 kg) for a combination of both, diet and exercise. The researchers also discovered that diet was the most effective option in preventing pregnancy complications, including pre-eclampsia, diabetes, high blood pressure and premature birth.

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What should women eat during pregnancy?

Naturally, balance is essential. Women should have at least five portions of fruits and veggies a day, a good amount of protein, fiber, calcium, iron, and starchy foods. Iron is extremely important for women, as it is a major part of hemoglobin production. A woman's body absorbs iron more efficiently when she is pregnant, so she has to consume more of it to make sure that both she and her baby have an adequate oxygen supply.