Prof. Dr. Werner Seebauer is Dean of Studies – Association of German Preventologists, Head of Preventive Medicine Department of Institute of Transcultural Health Sciences (European University Viadrina) and Head of Preventive Medicine – NESA (The New European Surgical Academy).
Since 2000, prof. dr. Werner Seebauer worked only in preventive medicine, after ten years spent at the Frankfurt University Hospital.
He is also involved in the medical professionals training for nutrition and prevention.
MediHelp International contributes to the medical science development and is actively involved in the international social responsibility advocacy.
The diet during this time
Twice better instead of twice as much
Risks at pregnancy and lactation period in the context of nutrition factors
- Malnutrition (pronounced macro- and micronutrient deficiencies)
- Pronounced mineral deficiency (e.g., iodine)
- pronounced vitamin D deficiency
* due to low sun exposure (Vitamin D deficiency, for example, due to body coverage, dark skin color, season)
- unbalanced vegetarian- or vegan- diet, or some culturally influenced diets
- Smokers *
- Alcohol consumption *
- Higher pollutant exposures * (environmental but also food pollutants)
- Acute infections * (toxoplasmosis, listeriosis, streptococci, chickenpox, rubella and other infections caused by viruses, bacteria or mycosis)
- Some chronic diseases *
- Overweight or underweight*
- Follow-up pregnancy in a short time
- Pregnancies with twins or more babies
- Adolescents women
* These factors are already inherent risk factors; in the context of nutrition or supplementation, they require more nutrients. If they are inadequate this may increase the maternal and child risks during pregnancy and later.
At this point, the topics are treated only in the context of nutrition. Issues related to infection risks will be discussed later. The toxic aspects of smoking, alcohol, and drugs are not treated extra. Their harmfulness is well known and beyond doubt.
At some point in the letter, a few background information are given, which are not necessary for the practical nutrition consultation and realization. However, they are given to get some insight into the study situation and coherence.
Recommendations - already during planning the pregnancy
The general recommendations for nutrition, supplements and the avoidance of pollutants already apply to the period before pregnancy in the planning and then they become even more important from the onset of pregnancy. In addition to the recommendations of nutrition topics presented here, for the other factors of a healthy lifestyle should, of course, also be given better attention (sufficient physical activity, good sleep, stress reduction, etc.).
For the safe supply of nutrients, which are often suboptimal or deficient, some supplements are regularly recommended. These are essentially folic acid, iodine, and on-demand iron. These are usually useful and often even necessary to reduce the risk of malformations of the child and pregnancy complications.
Also, for the additional intake of omega-3 fatty acids (DHA and EPA) and vitamin D, some data that prove a benefit. Whether vitamin D should be supplemented depends on the season and the sun's contact with the skin; Omega-3 fatty acids should be extra supplemented depending on your diet.
The recommendations usually refer to "normal" pregnancies. In the case of existing diseases and or severely overweight or underweight women, smokers, alcoholics, or other complications the conditions should be discussed with the gynecologist individually.
More information on nutrition’s health programming to later years “Metabolic Programming” already in the fetus and infant
Epidemiological data from large studies show convincing evidence that the risk for children or adults chronic diseases is influenced not only by genetic dispositions but also by lifestyle factors such as nutrition.
In the study of the time factors and chronology of the influencing variables, it is shown that early health effects are already being characterized during early, important stages of development of the fetus and infant. This is done through hormones and metabolic processes and is defined as "Metabolic Programming".
In the context of this programming, study data recognized lifelong imprint effects on the health or various chronic disease risks, as well as on neurological functions and even behavioral disorders. This decisively influences well-being and can influence development opportunities.
For example, over-nutrition of the mother during pregnancy may cause adverse fetal programming and risk predisposition to the metabolic syndrome (prediabetes) (DGE Nutrition Review7/08).
About 20 million Germans are affected by metabolic syndrome and the numbers have been increasing steadily in recent years. Later lifestyle factors also play important roles in the development, but early programming can make the unfavorable progression and make the problem solving difficult.
Even during breastfeeding, the child’s metabolic programming continues.
"Normal" weight gain during pregnancy
Overweight of the mother - risks for mother and child
Because overweight and pre-pregnancy obesity, as well as excessive weight gain during pregnancy, increase the overweight risk* for women and children over the following years, existing overweight should be reduced or eliminated before pregnancy. The weight of the woman before the start of pregnancy probably has an even greater influence on the overweight risk and other health aspects of the child.
* Increased risks are more likely to develop gestational diabetes, high blood pressure, pre-eclampsia as well as over-growth of the fetus with overall increased birth complications.
By contrast, being underweight before pregnancy can increase the risk of miscarriages (abortions), premature births, or low birth weight infants.
With gestational diabetes also miscarriages and premature births are more common. Early-onset of pregnancy diabetes can lead, undetected and untreated, to infantile death or for example malformations of the heart.
More on gestational diabetes (prevention, screening, and therapy)
Extreme weight loss diets during pregnancy are not recommended. An overweight pregnant woman, however, should have a lower weight gain during pregnancy.
It is best to lose weight before pregnancy. For women with adiposity already a weight reduction of 5-10% of the starting weight before pregnancy can have a significant positive effect on the health and reduce some risks.From: Diet and lifestyle during pregnancy Thieme reprint 2018 (JournalGerman language)
In a pregnant woman with a starting position at a normal weight, a normal pregnancy weight gain is between 11 - 16 kg. While it should be slightly more kilograms in underweight women, overweight should increase significantly less (see Table 1). The later risk of overweight in women and in children increases more with higher weight gain and especially if women were already overweight before pregnancy.
Table 1: IOM Report 2009
Prepregnancy BMI (kg/m2)
Overall Weight – Gain kg
2nd and 3rd Trimester Rate of Weight Gain kg / week
|<18.5 underweight||12,7 - 18,14kg||0,45kg|
|18.5 - 24.9 normal weight||11,34 - 15,88kg||0,45kg|
|25.0 - 29.9 overweight
||6,8 - 11,34kg
|>30 obese||5 - 9,1kg||0,23kg|
Institute of Medicine. Weight gain during pregnancy: reexamining the guidelines. Washington, D.C.: National Academy Press, 2009
Hivert Research Journal Obesity, 2016, Volume24, Issue7; Goldberg, Gail R. Nursing Standard (through 2013); Rasmussen National Academy Press, 2009; RF Goldstein, JAMA. 2017; MargerisonZilko CE, American Journal of Obstetrics and Gynecology, Volume 202, Issue 6, 2010
The normal weight gain during pregnancy is calculated based on the following factors
- At birth, your baby weighs about 3.300g.
- During pregnancy, the uterus increases significantly by about 900g
- The placenta weighs around 600g
- Breasts are about 400g heavier.
- The blood volume increases by 1,200g.
- The extra fluid in the body weights of about 2,600g.
- About 2,500g are for more fat reserves that provide additional energy for breastfeeding.
Nutrient and energy requirements during pregnancy
The nutrient and energy requirements are increased during pregnancy, but not so much that the women must eat for two. The device is: not twice as much, but twice as good!
The need for some micronutrients increases more than the energy requirement.
Only in the last pregnancy months, the energy requirement is just about 10% higher than before pregnancy.
- In the second trimester of pregnancy, the energy requirement is about 250 kcal per day higher than before
- and in the third trimester (last 3 months) the demand is 500 kcal per day higher if the physical activity remains unimpaired.
Many women, however, have a significantly reduced physical activity in the last months of pregnancy, so then no increased energy intake is needed.
Diet in pregnancy and lactation period
Nutritional optimization should best be realized in the long term before pregnancy.
The nutritional recommendations for pregnancy and the healthy development of the child during pregnancy and breastfeeding are not fundamentally different from the previous recommendations made in the Nutrition Circle and the Food Pyramid.
There are a few exceptions that concern the prevention of a potential risk of infection from the food, or potentially higher levels of pollution load, which are more damaging to the child than to adults (see below "what should be avoided").
"Observational studies show a lower risk of gestational diabetes in diets high in vegetables, fruits, whole grains, nuts, legumes, and fish; a diet rich in fat, lots of red meat and eggs is associated with a higher risk of gestational diabetes "(German Nutrition Society DGE 2018).
The biggest part of the diet should depend on vegetables (about 20%) and whole grains (about 25%). Almost as large amounts should come from the groups of legumes and fruits (about 15% each).
You can also vary the quantities between the groups here.
For various reasons, it seems to be a significant advantage that 75% of the composition consists of high-quality food of vegan origin and only about 25% food of animal origin.
- For vegetables and fruits, you can get the message "5 a day", which means 5 servings (3 vegetables, 2 fruits) a day - one serving is equivalent to a handful. The wide-ranging variety (preferably different colors) is important.
- Besides, legumes and whole grains as well as nuts, seeds and sprouts should be consumed often.
- Depending on physical activity and ambient temperature (lots of sweat) the women need plenty of fluids (preferably calorie-free - water and/or fruit teas). - often about 2-3 liters per day. With very hot temperatures and high physical activity, the demand quantity can multiply.
- Consumption of 1-2 servings of high-fat fish per week is recommended*
- best e.g. salmon, herring and mackerel - always low in pollution -best from the deep sea (e.g. the Arctic Northern Atlantic) - to ensure omega-3 fatty acid intake. If necessary, supplementation (see below)
* If there is any uncertainty as to whether the fish has a higher exposure to mercury, arsenic, and other metals, it is difficult to decide whether you compose your diet without fish as a precaution (for marine fish from regions of higher pollution load, e.g.from the Baltic Sea and generally more inhabited, farmed or industrial used coastal regions, better abstain this fish and take additionally more supplementation with omega-3 fatty acids. The supplement should also be tested to have no harmful substances.
- For Amino Acids – Proteins in addition to bioavailability, the content, the combination and the preparation is important. In our culture, there is usually no deficiency of proteins.
- A good diet is also possible without animal protein: The combination of legumes (also as shake powder and pastes or as soy drink, etc.) plus nuts and seeds (also as pastes or in bread, in muesli, etc.) delivers very good sources.
- Food of animal origin should be consumed to a smaller extent. Especially high-fat foods of the animal source (except fatty fish) should be reduced - also red meat (this is any meat except poultry meat) should be reduced. Sausages should rather be avoided.
- For fats, preference should be given to oils made from rapeseed and olives, as well as linseed and nut oils are good.
- Fat sources with too much saturated fatty acids as well as high omega-6 fatty acid levels should be restricted.
- Hardened fats and trans-fatty acids should also be avoided as far as possible (for example, in spread-hardened oils, fried products, partly pastries.
- Low amounts of sweets, sugary drinks, and snack foods (as well as other things contained in the top of the food pyramid) are occasionally tolerable.
- Alcohol should be avoided absolutely.
Read more about pollutants and reducing or avoiding foods below
What Pregnant Women Should Not Eat - Protection from Food Infections and Pollutants
At this point, foods and things are listed that women should avoid or reduce as much as possible during pregnancy and breastfeeding period because there is an increased risk of infection and potential harm to the child. In general, any human being can be harmed by pollutants in the long term, but certain pollutants are not acutely effective (acute relevant toxic).
In the fetus and infants, many pollutants are much more effective, more toxic. Since the pollutants often act on the child through the placenta and the mother's milk, fetus and infants have a much higher dose-response relationship, according to their low body mass, the toxicity there is significantly stronger.
A few insights, for example, mercury, arsenic, and cadmium
Mercury (e.g. from shellfish and larger predatory fish) is estimated that the fetus and infants are 5-10 times more sensitive for it, and it is estimated to have faster and higher neurotoxicity, which can lead to developmental and behavioral disorders as well as speech-, memory- and attention deficits.
Motoric and cognitive developmental disorders due to heavy metals are especially noticeable. At mercury stressed mothers, the infants first abnormalities are: delayed learning to walk and to speak, and later at four to seven-year-old children auditive problems (hearing difficulty) and increased muscle tonus in the legs were also noted
Longer has known the burden of rice with cadmium and arsenic (mainly from water-farming areas in Asia). Both also have neurotoxic effects.
Among the most heavily contaminated rice varieties, some toxicologists estimate that the highest tolerable arsenic dose in infants is already reached in as little as 20g rice waffles per week.
As a good alternative, you can use corn waffles for children. For corn and other cereals have found no arsenic pollution.
For adults, it is recommended to use the rice prepared according to the Indian method. Boil the rice in six times the amount of water and then pour off the water at the end. Chemists have found that the arsenic content can be reduced by 35 to 45% with this preparation method.
In addition to rice, marine animals and algae often contain arsenic.
For puffed rice (rice waffles) was measured more than 10-30 times the dose of arsenic than is allowed in drinking water.
In infants, related to the body weight, the intake of arsenic through rice-containing food is 2 to 3 times higher than that of adults, so it is recommended to take extra care.
The European Food Safety Authority (EFSA) calculated 2014 that infants fed on rice-based infant-formula can ingest 1.96 μg inorganic arsenic /kg bw /day from this food.
The Federal Institute for Risk Assessment Germany (BfR) declares in 2015 that the tolerable daily intake of arsenic cannot be precisely defined and only points out that caution is required in babies and infants.
However, due to the known toxicological research results, the risk should be rated higher and precautionary rice from wetlands should be avoided during pregnancy and in the food of babies as well infants (rice from dry cultivation is preferable).
The Bavarian State Office for Health and Food Safety calculated after analyzing various diets with rice 2010-2011 (rice waffles were the highest-burden), that for a child (age 1-3 years) with consistent consumption of up to 11 mini-rice waffles (of 2g each) per month - so 22g per month - no significant health risk is to be expected. If children occasionally consume larger quantities of rice waffles, it is advisable to increase the intervals between eating such waffles. It is recommended to change the cereals for small children more often.
My recommendation is, to abstain from the rice for babies and infants if you do not know where the rice comes from and what arsenic doses it contains.
Note: The otherwise healthier wholegrain rice contains higher arsenic values than the polished white rice when exposed to arsenic (from water farming).
In the following, further background information is omitted for a better overview. It merely lists what should be avoided or at least reduced.
What pregnant and breastfeeding women should avoid or reduce - overview
- Avoid total raw animal foods
- Danger of toxoplasmosis and listeriosis (heating for at least 2 minutes to over 70°C inside the food kills listeria and toxoplasma)
- Danger of salmonella infection (to kill salmonella it takes at least 10 minutes to over 70°C inside the foods
- Do not consume large predatory fish, shellfish and crustaceans, as well as coastal sea bottom (ground) animals>> [Heavy metal pollution, mercury, lead, etc.] - e.g. Tuna, shark, swordfish, king mackerel, crabs, seashells, octopus, etc.
- No raw fish and fish products, sushi, etc. >> infection risk
- No pickled fish and smoked fish>> still infection risk
- No products from raw milk* like cheese (listeriosis risk): soft cheese, not even from heat-treated milk (only pasteurized)
- No unpasteurized milk (especially no unpasteurized goat's milk)
* Annotation: Cream cheese, cottage cheese or yogurt are harmless, as they are sold in Germany only from pasteurized milk. Raw milk products must be legally declared as such ("made from raw milk")
- No raw meat – only strong cooked meat
- No raw sausages like raw ham, salami, meat-sausage, etc.
- No raw eggs and any foods and products made from them without cooking - only eggs that are hard-boiled
- For eggs and egg products (including desserts) only really longer heated egg products
- Vit. A-supplements should be avoided by pregnant women
- Avoid liver – it has high dose Vitamin A (avoid in the first trimester of pregnancy in any case - but later better too)
- Pro-Retinol = ß-Carotene is the precursor of Vitamin A >> it is harmless*
* (Only for smokers ß-Carotene is questionable as a high dose supplement! In the matrix of normal food it has no risk – and pregnant as well as breastfeeding women should not smoke in any case!)
- No alcohol - absolutely no smoking (also no "passive smoking", no rooms where smoking is or was before) - no other drugs.
- This should already be taken very seriously during the period of pregnancy planning
Alcohol, smoking and other drugs should not be trivialized – you should not underestimate it
By such pollutants during pregnancy and possibly even during the pregnancy planning period, for example, can lead to miscarriages, premature birth, malformations, damage to nerve cells and permanent disability. As a result of the damage, some irreversible mental retardations are observed in the children.
There is no secure time-window for pregnancy planning and during the pregnancy, in which these pollutants would not pose any risk. Therefore, alcohol, as well as smoking and other drugs should be avoided.
Low doses of alcohol are considered harmless by some sources, but there is no safety.
Even though "the dose makes the poison", it is always important to note that various environmental pollution or toxins can accumulate and can mutually increase the damage effects - and sometimes even potentiate them. It must be specially warned in these sensitive phases. So even a low dose is not safe.
The quitting of smoking should be done by the whole family in the household in sufficient time before the pregnancy planning and be sustained (for this purpose it is recommended to use help programs of health institutions). For Babies, infants, children, and adolescents, smoke (passive smoking) is much more harmful than for adults.
Even e-cigarettes are a source of risk and should be avoided.
Some medications - pharmaceutics must be avoided during pregnancy and breastfeeding
Pregnant and breastfeeding women should take or stop medicines only after medical consultation.
For the fetus and the developing child, certain pharmaceuticals may have a different effect than for adults and may have adverse effects that may even cause serious harm.
For the vast majority of pharmaceutics, however, there are no adequate studies in connection with pregnancy and during breastfeeding, because tests are not ethically acceptable and prohibit during this time. In this respect, one is very careful and advises against some medicines for safety reasons.
Women with pregnancy planning and pregnant or breastfeeding women should always seek medical advice if they need medication. And the physician must weigh the benefit-risk ratio strictly if no alternative is possible for a safe declared drug.
At the medical University of Charité Berlin, you can find information on medicines (safety or doubtfulness or contraindication) during pregnancy and lactation on the websitewww.embryotox.de. (German language)
Furthermore, pregnant women should reduce or avoid as much as possible:
- Fried foods should also be reduced or better avoided
- Chips and soluble dried coffee (e.g. Nescafe) are to restrict or rather to avoid (relation to acrylamide)
- Avoid food packaged in plastic (PCBs and softeners) - Be careful to use Tetra Pak and plastic bottles (Tetra Pak carton for beverage or milk packaging is coated inside with plastic and aluminum foil)
- Lead-containing e.g. in drinking water from old pipes in old houses (lead pies were allowed in houses of south Germany until 1878 Nord- u. East Germany until the 1970s)
- Lead is partly elevated in wild mushrooms (from the forest), seafood, venison meat, tobacco smoke, but also large-leafed lettuce varieties, which were grown close to industry and high-traffic roads
- Rice from water-growing areas is rather to avoid (potentially too high cadmium and arsenic pollution)
- Cadmium in tobacco smoke, road traffic,
- Cadmium is released via acidic food from ceramic enamel
- Cadmium is increased in chocolate from regions with many volcanoes (cocoa or chocolate from Africa and some areas of South America are less loaded – compared to Middle America)
- Dioxin: Baltic herring and Baltic salmon are more heavily polluted
- River trout (depending on the creek) are mostly not heavily polluted and fish from the Arctic ocean is also usually less polluted
- Avoid aflatoxins from mold -beware of grains, nuts, fruits, spices
- Quinine-containing drinks should not be consumed in large quantities
- Avoid in food-production-related toxins* by strong roasting and grilling – e.g. cereals and meat
- do not eat heavily grilled - burnt (charred) pieces of meat, fish, vegetable, and pastries
- Restrict or avoid sausage and other cured or smoked meat or fish
- Avoid strongly toasted (roasted) pastry should be avoided.
* (PAHs and HAAs - Polycyclic aromatic hydrocarbons and heterocyclic (aromatic) amines from incomplete high-temperature burning)
- Too high nitrate and nitrosamine levels should be restricted or avoided (for example arugula salad, rhubarb, sausage, cured meat)
Coffee - caffeinated drinks
Pregnant women should only drink caffeine-containing drinks in moderate amounts.
Energy drinks pregnant women should better avoid, because of the high sugar content and the unpredictable interactions with other ingredients (such as taurine, guarana, sugar substitutes or sweeteners and other substances)
Pregnant women can generally enjoy up to 3 small cups (125 ml) of unsweetened coffee safely throughout the day. However, since caffeine pass the placenta, and the effects on the fetus, which is very sensitive to it, can be difficult to study, pregnant women should better drink only one cup of coffee (125 ml) per day if it is not decaffeinated.
According to the EFSA (European Food Safety Authority), a caffeine dose of 200 mg/day is given as a safe dose for the healthy pregnant woman.
Meta-analyses of studies (case-control studies) show a significantly increased risk of miscarriage from 300 mg caffeine/day (especially in the first few months).
As a rough orientation you can estimate*:
- A cup of coffee (125-140ml) has about 67 - 112mg of caffeine. By the way, it is similar to strong brewed black tea.
- A cup of espresso (50 ml) has about 50-60 mg of caffeine.
- A glass of cola (200ml) usually contains between 10-40 mg of caffeine.
- A cup of common black tea (140 ml) contains 20-50mg of caffeine; green tea has lower caffeine or theophylline levels and the effects are delayed.
* according to the federal food key 1995 - Kirschbaum et al. 2001
Following the next topics
On the subject of vegetarian and vegan nutrition in pregnancy, with vegan or vegetarian nutrition, a deficiency can arise mainly for:
- Vitamin B12,
- Folic acid,
- and possibly zinc * as well as proteins *
- There may also be a relative deficiency in the bioactive forms of omega-3 fatty acids (EPA and DHA).
- possibly calcium (for vegans) – Topic Antinutrients
Supplementation of micronutrients before and during pregnancy and lactation
The need for a range of micronutrients increases significantly during pregnancy and lactation time, but the higher doses of the most vitamins and minerals can be met by a balanced selection of foods with a high nutrient density, without the diet is high caloric. The balanced consumption of fruits and vegetables (including salads), as well as whole grains, legumes, sprouts, and seeds provides a good balance of nutrients.
For some nutrients, it may be harder to meet the needs well, so for safety's sake, supplementation with standardized supplements is recommended.
This concerns folic acid, iodine and iron, if required. Further supplementation needs are diet-related or due to other factors, such as illnesses or season of the year.