// Nutrition for pregnancy
by Tanya Lewis
Pregnancy is an important time for good nutrition and not the time to be going on fad diets or restricting intake. It is important for personal trainers to be aware of key nutrition recommendations during pregnancy to ensure no harm is done if discussing food intake. Remember, for dietary prescription and any individual concerns, clients should be referred to an Accredited Practising Dietitian who has experience in antenatal care.
To test your knowledge of pregnancy nutrition, let’s start with a small quiz:
One of your long term clients, Natalie, is 18 weeks pregnant. She is concerned that she is gaining weight at almost half a kilogram every week and always seems hungry. Natalie has always enjoyed her training and continues to train
regularly but with decreased intensity. Her pre-pregnancy BMI was 21 kg/m2.
1. Is Natalie’s weight gain;
a) Not enough
2. Which statement best describes the changes to Natalie’s metabolic rate?
a) Metabolic rate has dropped signifi cantly as the body tries to conserve energy while pregnant; Natalie needs to be careful not to overeat
b) Metabolic rate increases during pregnancy, due to the demands of making a baby and increased body weight. Natalie is probably hungry due to increased energy requirements despite decrease in exercise intensity.
c) Natalie is now ‘eating for two’, her metabolic rate has almost doubled, her blood pressure, temperature and heart rate are all much higher than pre-pregnancy.
3. What would be the most appropriate choice for Natalie if she is buying her lunch:
a) Vegetarian sushi
b) Salad pack with coleslaw, Greek salad and chicken
c) Ham and salad multigrain roll
d) Baked potato with baked beans and grated cheese.
PHYSIOLOGICAL AND WEIGHT CHANGES DURING PREGNANCY
The amount of weight gained during pregnancy is individual and will vary according to pre-pregnancy weight, fl uid gains
and the number of babies inside! Excess weight gain can lead to complications including hypertension, increased risk
of gestational diabetes and large babies. Inadequate weight gain in the mother can cause growth restriction of the baby.
In May 2009, The Institute Of Medicine (IOM) in the US updated the recommended range of weight gain during
pregnancy based on pre-pregnancy BMI. The chart below is adapted from their recommendations (www.IOM.edu). As you can see, Natalie’s weight gain is quite appropriate (Answer to Question 1 is ‘b’).
Recommendations for Total and Rate of Weight Gain during pregnancy in singletons.
Regarding Question 2: ‘Eating for Two’ is an overstatement of the change to energy requirements. Metabolic functions
are increased during pregnancy to provide for the demands of growing baby, placenta and uterus. The mother’s basal metabolic rate does increase to a variable degree, though in some women this is coupled with decreased exercise and increased rest. It is estimated an extra ~1,200 kJ per day is required, assuming a healthy weight to start with and maintenance of some physical activity. Natalie is probably hungry because her body needs the fuel (Answer to Question 2 is ‘b’).
RECOMMENDED FOODS, VITAMINS AND MINERALS
Normal healthy eating recommendations are important in pregnancy and should include a variety of food from all the food groups. Regular multivitamins or supplemented beverages/meal replacements are not recommended as they can be too high in certain vitamins, including vitamin A. A specific pregnancy multivitamin can often be useful but should be discussed
with a doctor or dietitian. No food group should be excluded and if your client has food allergy or intolerance she should also speak with a dietitian.
Specific vitamins and minerals that are important include:
Folate – A folate supplement is recommended prior to and during the first three months of pregnancy to help reduce risk of neural tube defects. Many foods in Australia are also supplemented with folate.
Iodine – Since October 2009, iodised salt is used in Australian bread, but many health professionals still recommend supplementation during pregnancy to help ensure elevated requirements are met for optimal brain development.
Iron – Because blood volume increases, iron requirements increase significantly. The average requirement of iron is 22mg/day, but some women will need 27mg/day or more (compare this with a recommended daily intake (RDI) of 8mg per day for males). Red meat is high in iron and many foods are iron-fortifi ed, though some women need a supplement to prevent anaemia which can lead to fatigue and increased susceptibility to infection.
Calcium – The baby will take the calcium it needs for growth and development but it is important that requirements are met so that the mother gets enough for her bone health too. Calcium requirements can easily be met by appropriate food
choices, but sometimes a supplement is necessary.
FOODS, SUBSTANCES AND BACTERIA TO AVOID
A number of foods pose a risk to pregnant women. Some of these foods contain substances known to cause harm in excess, while others may not necessarily be a problem but are more likely to contain, or be contaminated with, bacteria that can cause harm. Minimising risk and choosing safer alternatives is a good option.
LISTERIA AND OTHER BACTERIA
Listeria monocytogenes is a relatively uncommon food poisoning bacteria that may cause no symptoms in most people. However, it can be very dangerous for an unborn baby and could cause miscarriage or illness to the baby. It is important to minimise the chance. Many people know to avoid soft cheese and pâté but the following foods are also at higher risk of
• Deli meats including ham, turkey, pre-cooked cold chicken and chilled seafood.
• Pre-prepared salads (e.g. salad bars) and smorgasbord environments.
• Soft and semi-soft cheeses including camembert, ricotta and feta.
• Soft serve icecream and unpasteurised dairy foods.
• Pre-cooked rice and sushi
• Unwashed fruit/vegetables and sprouts.
Eggs should be fresh and well cooked and runny yolks should be avoided. Mayonnaise is a common source of raw
egg to be aware of.
Raw or undercooked meat poses a risk of toxoplasmosis, which can cause problems to the unborn child. Handling kitty litter or eating unwashed vegetables is an additional risk.
*It is also important to always wash hands before cooking/eating, observe ‘best before’ dates carefully and store foods at appropriate temperatures.
Fish provide a number of benefi ts to pregnant women including omega 3 fats shown to be important in development of the baby. However, some fish is high in mercury which can be harmful. Food Standards Australia and New Zealand (FSANZ) has a useful fact sheet specifying recommended portions, available for free download from www.foodstandards.gov.au/_srcfi les/mercury_in_fish_brochure_lowres.pdf
There is no need to completely avoid caffeine, but 200 to 300mg per day is a recommended maximum. The amount of caffeine in beverages varies, especially brewed coffee, but generally this is equivalent to one to two cups of coffee, or three to four cups of tea per day, depending on size and strength.
The National Health and Medical Research Council recommend that you don’t drink alcohol during pregnancy or while breastfeeding. So, Natalie’s most appropriate lunch choice would be the baked potato; it includes a range of food groups, contains protein, iron and calcium and is appropriate for her energy needs. The other options contain foods at higher risk of listeria, the salad is also missing carbohydrate for energy and the sushi is also lacking protein (Answer to Question 3 is ‘d’).
Tanya Lewis, BA
Tanya is am Accredited Practising Dietitian, sports dietitian, personal trainer and a director of Life Personal Trainers in Adelaide. She works mainly in the areas of sports nutrition, eating disorders, paediatric nutrition, weight management and corporate health. Tanya promotes the value of life-long good nutrition and exercise habits, rather than the quick fix diet cycle, for children and adults of all ages.
NETWORK MAGAZINE • AUTUMN 2010 • PP33-35