Pregnancy Nutrition Concerns

Cravings

Cravings in pregnancy may be related to the normal change in sensory perception women experience. Pregnant woman are more sensitive to smells, more sensitive to taste and more alert to non-verbal communication cues. The most commonly reported cravings are for sweet foods, followed by sour and then salty.

Cravings are usually harmless, but can become a problem if the craving interferes with good nutrition. Remember, a pregnant woman is dealing with several other factors, such as nausea and food aversions, that can make healthy eating a challenge. Responding to healthy cravings requires common sense to make good eating choices while focusing on the flavors you desire. For example, you may have cravings for baked potatoes. While a baked potato is not bad, excess of any food skews the nutritional balance. Limit yourself to one baked potato a day and top it with healthy choices from other food groups to balance out your diet.

Pica

Some women experience cravings for non-food substances such as laundry starch, crayons, ice, dirt and cravings for smells like ammonia or nail polish remover. These non-food cravings are called pica, and may present a danger for you and your baby. Eating non-food products is associated with constipation, bowel obstruction, elevated blood pressure and anemia.

Women report not just being attracted to the taste, but also the smell and the feeling of the item in the mouth. Most women who experience pica have a craving for one item throughout the entire pregnancy. Many women continue eating the substance, even if they fear it is unsafe for the baby.

There is a theory that pica developed as a protection for the baby. This theory is based on studies which show some clays that are commonly eaten can strengthen the digestive system and prevent toxins in foods from being absorbed by the gut. The theory continues that pica develops because the woman is low in iron and eating clay provides her body with iron. Unfortunately, this theory is not supported by science.

The first problem with the theory is that while some clays have some beneficial effects, clays also interfere with absorption of some nutrients; most commonly iron, zinc and potassium. So rather than improving her health, eating clay is likely to have no effect or a negative effect on a woman's health. There is no evidence the iron in clay contributes to the body's supply of iron. Rather than increasing the supply of iron, clay actually binds to the iron available in food, reducing the amount of iron a woman is able to obtain from her diet. This means women who eat clay are more likely to have low iron. So women are not eating clay in response to anemia, but experiencing anemia because they are eating clay.

The second problem with the theory is that not all non-food substances commonly eaten are high in minerals. Women not only have cravings for clay, but also ice, charcoal, ash, paper, chalk, baby powder, coffee grounds, egg shells or cloth. While there are case reports of women overcoming their pica cravings when given nutritional supplements, well controlled studies consistently demonstrate no decrease in the cravings with vitamin and mineral supplementation.

Women who experience pica will often keep the cravings secret, even if they believe it is causing a problem. Successfully stopping eating the non-food is difficult. It may only be possible by substituting a food item for the craved non-food item. Some women may find it easier to stop by using some outside force. This could be someone reminding her not to eat it or removing the item from her home to make it difficult to access.

References

Cooksey, N.R. (1995). Pica and olfactory craving of pregnancy: How deep are the secrets? Birth, 22(3): 129-137.

Stadtlander, L. (2013). Memory and perceptual changes during pregnancy. International Journal of Childbirth Education, 28(2):49-53.

Young, S.L. (2010). Pica in Pregnancy: New ideas about an old condition. Annual Review of Nursing, 30:403-422.