The development of the unborn child depends on the health and behavior of the expectant mother. Nutrition plays a major role. This article explains which nutrients are particularly important and which foods pregnant women should avoid.
At a glance
- Expectant mothers should eat as balanced a diet as possible in order to provide their babies with all the nutrients they need.
- A woman’s body needs larger quantities of certain vitamins and minerals during pregnancy. The most important of these are folic acid and iodine.
- If animal-based foods are not consumed, care must be taken to ensure an adequate supply of iron, vitamin B12, and zinc.
- Raw animal products, such as raw (unpasteurized) milk, raw fish, and uncooked eggs, should be avoided by pregnant women (due to the risk of infection).
- Poppy seeds, licorice, and caffeinated drinks should only be consumed in small quantities during pregnancy.
- Weight gain is quite normal, but too much or too little weight gain can also be a warning sign.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What role does nutrition play during pregnancy?
A healthy and high-quality diet is particularly important during pregnancy, as it benefits the health of both the mother and the unborn child. Anyone who eats a balanced diet during pregnancy has no real need to worry. There are only a few things to keep in mind.
In general, pregnant women should eat a diet including plenty of fruit and vegetables, animal-based foods in moderation, and a small number of sweet treats and snacks. Expectant mothers should completely avoid certain foods, such as raw animal products, so as not to put their unborn child at risk. As a rule, additional intake of folic acid and iodine is also necessary to meet the special mineral and vitamin requirements during pregnancy.
How do vitamin and nutrient requirements change during pregnancy?
Calorie requirements increase slightly as of the second trimester of pregnancy. However, at this point, many pregnant women also exercise significantly less than before and burn fewer calories as a result. This means that, in most cases, there’s no need to eat more than usual. In addition, smaller meals are preferable to larger meals in the later stages of pregnancy. This is because, as the child grows, increasing pressure is placed on the woman’s stomach and intestines within the abdominal space.
The body needs larger quantities of certain vitamins and minerals during pregnancy. The most important of these are folic acid and iodine. However, iron, long-chain omega-3 fatty acids, and vitamin D are also important. The woman’s gynecologist will address which preparations are needed and which dosage makes sense.
An additional intake of folic acid and iodine is recommended for almost all pregnant women
Folic acid and iodine should be taken by almost all pregnant women in addition to eating a balanced diet. In many cases, the body’s increased requirements cannot be met by diet alone. A folic acid or iodine deficiency comes with a high risk of developmental disorders in the unborn child and should be avoided at all costs. The German Nutrition Society (Deutsche Gesellschaft für Ernährung, DGE) therefore recommends an additional intake of 400 micrograms of folic acid by the end of the first trimester of pregnancy. The recommendation for additional iodine is 100 to 150 micrograms per day.
However, the recommendation for iodine does not apply to women with thyroid disease. In this case, it is important to talk to a doctor before taking iodine.
Important: If possible, folic acid supplements should be started before pregnancy begins. This B vitamin is needed in early pregnancy in particular. It can take several weeks until the required concentration is reached in the blood.
Only take other preparations if a deficiency is detected
An iron deficiency can also cause complications during pregnancy. For this reason, iron levels are checked during prenatal check-ups. Most pregnant women can meet their iron requirements by eating a balanced diet. Meat in particular contains easily digestible iron. The body is less able to utilize iron from plant foods. As a result, iron levels should be carefully monitored in women who follow vegetarian or vegan diets. However, an iron supplement should only be taken after a deficiency has been diagnosed by a doctor, as excessive iron intake can also have negative effects on health.
Some studies have shown that long-chain omega-3 fatty acids such as docosahexenoic acid (DHA) can reduce the risk of premature birth. In addition, DHA is important for the development of visual function and the brain in the unborn child. Vegetable oils, especially linseed oil, and fatty salt-water fish such as salmon, mackerel, and herring are particularly rich in omega-3 fatty acids.
A vitamin D deficiency is now widespread in northern industrialized nations. However, it is unclear whether such a deficiency has an influence on pregnancy or whether undesirable side effects can be caused by taking vitamin D supplements. To ensure an adequate supply of vitamin D, it is sufficient to spend at least 5 to 25 minutes a day in the sun with the face, hands, and parts of the arms and legs uncovered. If a vitamin D deficiency is detected, the DGE recommends taking 20 micrograms (800 IU) of vitamin D per day. This recommendation also applies to pregnant and breastfeeding women. It’s best to talk to a doctor if you have any questions about vitamin D intake.
What should you be aware of if you follow a vegetarian or vegan diet?
In Germany, more and more people are adopting a vegetarian or vegan diet. Most vegans and vegetarians in the country are female and between 20 and 39 years old, i.e., women of childbearing age. As a result, the question of how to manage vegetarian and vegan diets during pregnancy is becoming increasingly important. Firstly, a distinction must be made between vegetarian diets (no fish or meat) and vegan diets (no animal products).
Vegetarian diet – pay attention to iron, vitamin B12, and zinc
A vegetarian diet that includes eggs and dairy products (i.e. an ovo-lacto vegetarian diet) typically offers an adequate amount of nutrients without any dietary supplements, except for folic acid and iodine. However, special attention should be paid to the iron, vitamin B12, and zinc, as these three nutrients are found primarily in meat products. If a deficiency is detected, dietary supplements are available.
Vegan diet – certain dietary supplements are required
The recommendations made for vegetarians also apply to vegans, but with some additions: taking vitamin B12 supplements is a must for pregnant women following a completely plant-based diet, as this vitamin is found almost exclusively in meat, fish and dairy products. Since vegans also do not eat calcium-rich animal products, they should eat ample calcium-rich plant foods such as dark-green vegetables (e.g. broccoli). Calcium-fortified foods, such as fruit juices and breakfast cereals, or dietary supplements can also be taken. Vegan women should have their mineral and vitamin levels checked during and, ideally, even before a planned pregnancy.
Important: Women who wish to have children and who, for personal or health reasons, abstain from certain foods, can seek support from a qualified nutritional counselor. This ensures that the unborn child is supplied with all essential nutrients.
For further useful information about vegetarian and vegan diets during pregnancy, visit the website of the Federal Center for Health Education (Bundeszentrale für gesundheitliche Aufklärung).
What foods should pregnant women avoid?
It is generally known that pregnant women should avoid alcohol and other drugs during pregnancy and while breastfeeding. However, some other foods should also be avoided during pregnancy. The reason for this is they may possibly be contaminated with certain pathogens that can trigger infections. Certain foods should also be consumed only in small quantities, as some of their ingredients may be harmful to the unborn child.
Raw milk, raw meat, and raw fish products
Raw animal products may contain the pathogens Listerium monocytogenes and Toxoplasma gondii. These pathogens, which are usually harmless to adults, can be dangerous to the unborn child by causing the infectious diseases listeriosis and toxoplasmosis, respectively. Among other things, listeria can cause meningitis in the unborn child. Toxoplasma can impair the development of the child’s nervous system. Furthermore, both pathogens can lead to miscarriages and premature births.
Listeria is mainly found in raw milk products, which include cheeses such as camembert, brie, feta and roquefort. Therefore, pregnant women should avoid eating these and other cheeses made from raw milk. Toxoplasma may be present in raw sausage products such as salami or in smoked fish. As a result, meat and fish should therefore only be consumed when well cooked. However, toxoplasmosis can also be triggered by eating unwashed fruit and vegetables. It is therefore recommended that fruit and vegetables be washed thoroughly, especially during pregnancy.
Raw eggs and poultry
Eggs can contain salmonella. These pathogens can be dangerous for the unborn child (salmonellosis). Therefore, eggs should only be consumed after they have been fully cooked during pregnancy. The same applies to poultry meat. Pregnant women should also avoid foods containing raw eggs.
Eating liver can harm the unborn child in the first trimester of pregnancy and should therefore be avoided completely during this period. The reason for this is that it contains significant amounts of vitamin A. Although vitamin A is important for development, too much of it is harmful to the unborn child, especially in the early stages of pregnancy. From the second trimester on, pregnant women may eat liver again, but only in small quantities (no more than 125 grams per week).
Poppy seeds may be contaminated with morphine during production. Because high concentrations of morphine can be harmful to health, pregnant women are advised not to eat large amounts of poppy seeds. However, eating small amounts of poppy seeds – especially if baked – is no cause for concern.
Due to the glycyrrhizin it contains, excessive consumption of licorice can cause side effects. It is also suspected that glycyrrhizin could have a negative effect on the development of the unborn child. However, studies have not yet been able to prove a clear connection. Nevertheless, the Bundeszentrum für Ernährung (German Federal Center for Nutrition) advises pregnant women to consume no more than 100 grams of licorice and no more than 50 grams of strong licorice per day.
Beverages containing caffeine, such as coffee, black and green tea, and cola, should be enjoyed with caution during pregnancy. Excessive caffeine intake appears to delay fetal growth and reduce the baby’s birth weight. The risk of miscarriage is also significantly increased when more than 300 milligrams of caffeine is consumed per day (about 3 to 4 cups of coffee). Up to 200 milligrams of caffeine per day is considered safe. This corresponds to about 2 large cups (200 ml) of coffee.
How much weight gain is “normal”?
Weight gain during pregnancy is completely normal. It occurs not only due to the weight of the growing child or the infamous “cravings” that the woman may experience. Much of the weight gained is stored fluid (water) that is needed for the placenta and amniotic fluid, for example.
Women gain more weight as their pregnancies progress. No general recommendation can be made as to how many kilos can or should be gained. The recommendations are based more on how much a woman weighed before pregnancy, i.e. whether she was underweight, overweight or of average weight. The body mass index (BMI) is also decisive. For average-weight women (BMI between 18.5 and 25), a weight gain of between 11 and 16 kilograms is perfectly fine. Underweight women (BMI below 18.5) may even gain up to 18 kilograms during pregnancy. However, for severely overweight (obese) women with a BMI over 30, weight gain during pregnancy should not exceed 9 kilograms.
Risks associated with gaining too much or too little weight
A very significant weight gain during pregnancy increases the risk of complications during the birth, as well as the risk of developing
gestational diabetes, for example. On the other hand, pregnant women who gain too little weight can also put both their own and their child’s health at risk, possibly leading to a premature birth or the baby having a low birth weight.
Important: Gaining weight very quickly during pregnancy (about 1 kilogram per week) can be a sign of illness and must be discussed with a doctor. This could indicate gestational diabetes or pre-eclampsia, which is potentially life-threatening. Rapid medical treatment is important in this case to protect the mother and child.
For further information about gaining weight during pregnancy, visit gesundheitsinformation.de.
Our article on Pregnancy dos and don’ts explains in more detail what is allowed and what must be avoided during pregnancy.
- Bundeszentrale für gesundheitliche Aufklärung (BZgA). familienplanung.de. Ernährung in der Schwangerschaft. Aufgerufen am 26.01.2021.
- Bundeszentrale für gesundheitliche Aufklärung (BZgA). familienplanung.de. Ernährungsrisiken in der Schwangerschaft. Aufgerufen am 26.01.2021.
- Bundeszentrale für gesundheitliche Aufklärung (BZgA). familienplanung.de. Gewicht und Gewichtszunahme in der Schwangerschaft. Aufgerufen am 26.01.2021.
- Bundeszentrale für gesundheitliche Aufklärung (BZgA). familienplanung.de. Vegetarische und vegane Ernährung in der Schwangerschaft. Aufgerufen am 26.01.2021.
- Deutsche Gesellschaft für Ernährung e.V. (DGE). Einheitliche Handlungsempfehlungen für die Schwangerschaft. Aufgerufen am 26.01.2021.
- Deutsche Gesellschaft für Ernährung e.V. (DGE). Referenzwerte: Vitamin D. Aufgerufen am 26.01.2021.
- Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG). Gewichtszunahme in der Schwangerschaft. Aufgerufen am 26.01.2021.
- Verbraucherzentrale. Jod, Folsäure, Eisen und Co - welche Nahrungsergänzungen brauchen Schwangere? Aufgerufen am 26.01.2021.
Reviewed by the German Midwifery Association (Deutsche Hebammenverband e.V.).As at: