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Leslie Beck's Food for Thought:

Multivitamins aid infant birth weight Add to ...

If you're thinking about getting pregnant or you are already pregnant, you need to ensure you're taking a daily multivitamin. Even if you have no plans to conceive, a one-a-day supplement should be part of your nutritional regimen.

Taking folic acid, a B vitamin needed for healthy cell division, before and during the early weeks of pregnancy, is vital to preventing neural tube defects in the developing fetus.

NTDs are serious birth defects caused by the incomplete development of the brain, spinal cord and/or their protective coverings that occurs around the fourth week of pregnancy.

But taking a multivitamin before and during pregnancy may do more than guard against NTDs. A report published in yesterday's issue of the Canadian Association Medical Journal revealed that taking a multivitamin during pregnancy - versus only folic acid and iron - offered significant protection from delivering a low birth-weight infant.

This finding was based on a review of 13 studies conducted in 30,000 women from a variety of populations: women who were well nourished and undernourished, as well as HIV-positive women.

Babies born under 5.5 pounds (2.5 kilograms) are considered low birth-weight babies. Low birth weight can result when babies are born early (before 37 weeks gestation), are small for their gestational age, or both.

Low birth weight is the main reason babies die in their first year of life. It also increases the risk a child will have learning and vision difficulties and grow up to develop heart disease, type 2 diabetes, stroke and high blood pressure.

To reduce the risk of NTDs, the Society of Obstetricians and Gynecologists of Canada advises healthy women to take a multivitamin with 0.4 to 1 milligrams of folic acid for at least two to three months before becoming pregnant and throughout pregnancy and breastfeeding.

Women at high risk for NTDs - including women with epilepsy, type 1 diabetes, a family history of NTDs and those who are obese - should take a supplement with 5 milligrams of folic acid a few months prior to pregnancy and continue until 12 weeks of her pregnancy. After 12 weeks, a multivitamin with 0.4 to 1 milligram of folic acid can be taken.

Mounting evidence also suggests that women who are not overweight and who are regular users of multivitamins before and during pregnancy have a lower risk of preeclampsia, a pregnancy disorder characterized by high blood pressure, fluid retention and protein in the urine. If left untreated, it can lead to eclampsia, a toxic and life-threatening condition.

Folic acid is needed for the development and function of blood vessels, a process thought to be disrupted in women with preeclampsia.

The bottom line: All women who could become pregnant, who are pregnant, and who are breastfeeding should take a daily multivitamin with folic acid. Do not take more than one daily dose to prevent getting too much vitamin A (retinol). During pregnancy, women should not consume more than 10,000 IU of vitamin A per day; doing so increases the risk of birth defects.

While taking a multivitamin helps ensure a healthy pregnancy, it's not your only safeguard. In addition to avoiding alcohol and limiting caffeine, the following nutrition strategies are important to protect the health of both moms-to-be and developing babies:

Don't eat for two During pregnancy, you need extra calories to support the growth of your baby, the placenta, as well the expansion of your own body's tissues. But it doesn't take a lot of food: calorie needs increase by 300 in the second and third trimesters. (Since energy expenditure changes only slightly and weight gain is minor during the first trimester, calorie needs don't change until trimester two.)

Weight gain guidelines are based on your body mass index before pregnancy. Women with a healthy pre pregnancy BMI (20-25) are advised to gain 25 to 35 pounds; underweight women can gain 28 to 40 pounds; those who are overweight (BMI 25.9 - 29.9) should gain no more than 25 pounds; obese women (BMI of 30 or greater) should gain 11 to 20 pounds. (Use an online calculator to determine your BMI.)

Add protein Protein needs increase by 21 grams during the second and third trimesters to support tissue growth. Add 300 calories to your diet by increasing your intake of protein-rich foods.

One ounce (30 grams) of cooked meat, chicken or fish supplies 7 grams of protein. So does one egg or two egg whites. One cup (250 ml) of milk or soy beverage delivers 8 to 9 grams of protein. One serving (3/4 cup) of legumes contains roughly 15 grams of protein.

Focus on folate While a multivitamin with folic acid (the synthetic version of folate) will help women meet increased folate requirements, pregnant women should also include folate-rich foods in their diet. God food sources include lentils, black beans, cooked spinach, asparagus, avocado and artichokes.

Increase iron To get the iron you need during pregnancy - 27 milligrams - choose a multivitamin with 16 to 27 milligrams of iron and add iron-rich foods to your diet. Beef, shrimp, sardines and trout are good sources of iron. Plant sources include legumes, pumpkin seeds, enriched breakfast cereals, nuts, raisins and prune juice.

Women who are iron deficient or who are vegetarians may require additional iron.

Get omega-3 fats Include 5 to 12 ounces of oily fish in your weekly diet to increase your intake of DHA, an omega-3 fat important for brain and eye development during pregnancy and breastfeeding. Good choices that are low in mercury include salmon, trout, sardines, herring, and Atlantic mackerel.

If you don't eat fish, consider taking a fish-oil supplement. Avoid fish-liver oil supplements which are often high in vitamin A. Vegetarian DHA supplements are available.

Eat safe foods The hormonal changes of pregnancy affect a woman's immune system, making her more susceptible to food poisoning, especially listeriosis. To minimize your risk, avoid hot dogs, deli meats (non-dried), semi and soft cheeses (e.g. feta, Brie, Camembert), refrigerated pâté and smoked seafood, and undercooked meat, poultry and fish.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. http://www.lesliebeck.com.

 

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