Pregnant women are being warned to watch what they eat during their pregnancy because eating habits – good and bad - can be picked up from within the womb.
Researchers from the CNRS research institute in France provided evidence at an annual meeting of the American Association for the Advancement of Science (AAAS), which indicates that taste preferences are set early in life – even as early as in the womb.
The decade-long research focused on a selected number of pregnant women and new mothers.
During the study, 12 pregnant women were given biscuits and sweets laced with aniseed. After they had given birth, their baby's reaction to certain foods were monitored against babies who were not exposed to food with aniseed.
Babies who were exposed to the strong flavour of aniseed in the womb seemed more interested and attracted to the food when presented with it. The study reveals that the babies smiled and moved towards the aniseed smell, whereas babies who were not exposed to it, turned away in disgust.
Scientists believe that babies can sense strong flavours by inhaling amniotic fluid from in the womb.
"During pregnancy, a woman is relatively vulnerable to her environment," Dr Benoist Schaal explained at the annual meeting, as reported by the Press Association.
"What the mother takes in a certain dose goes also to the foetus during a period when the brain is being formed, probably with long term consequences."
Reacting to the study’s findings, fertilty expert, Emma Cannon, told The Huffington Post: "I believe that a mother's experiences during pregnancy all have an impact on the growing baby. Even her inner most thoughts and feelings affect her baby.
"Food and emotions have a vibration and it is that vibration that forms part of the babies digestion and emotional capacity. However, I think that a woman's digestion can be compromised during pregnancy and that it is probably better to simplify the diet in order to keep her digestion and absorption healthy.
“Diet is important but digestion is everything and I think it is better to preserve the mother's and babies digestion rather than over complicate the system"
The study follows previous researcher by the Monell Chemical Senses Center, Philadephia, which also discovered that preferred taste is determined before babies leave the womb.
Food, particularly sweet tasting foodstuff, diffuses through the amniotic fluid predetermining their liking for sweet things. However, in contrast, bitter tastes don’t transfer through to the baby.
"Things like vanilla, carrot, garlic, aniseed, mint — these are some of the flavours that have been shown to be transmitted to amniotic fluid or mother's milk," Julie Mennella from the Monell Chemical Senses Center said in a statement.
Another study, this time on rats, by the Royal Veterinary College of London discovered that a mother’s diet of junk food could lead to them having children with sweet tooth’s – and at higher risk of diabetes and obesity later in life.
Researchers found that women who use pregnancy as an excuse to ‘eat for two’ and indulge in junk food may be putting their unborn baby at risk, as exposure to fatty, salty foods in the womb can have long-lasting effects on the part of the brain that controls appetite.
"Our study has shown that eating large quantities of junk food when pregnant and breastfeeding could impair the normal control of appetite and promote an exacerbated taste for junk food in offspring,” Dr Stephanie Bayol, from the study, said in a statement.
"This could send the offspring on the road to obesity and make the task of teaching healthy eating habits in children even more challenging."
Although it's clear from the study that pregnant women should maintain a healthy and nutritious diet, there are certain foods to be avoided, as they carry risks of miscarriage and birth defects:
Soft cheeses: These include Camembert, Brie, unpasteurised goats' cheese and blue cheese. These cheeses are made with mould and can contain listeria, a type of bacteria that increases risk of miscarriage. This is also applicable to all types of pâté, including vegetable.
Raw eggs and food containing raw or partially-cooked eggs: Only eat eggs that have been cooked enough for both the white and yolk to be solid. Raw eggs may contain salmonella, which causes food poisoning, which can be particularly unpleasant when you're pregnant.
Raw or undercooked meat: Make sure you only eat meat that has been well cooked as raw meat can contain salmonella and lead to food poisoning. This is especially important with poultry and products made from minced meat. Make sure these are cooked until they are steaming hot all the way through and no pink meat is left.
Some types of fish: Avoid eating shark, swordfish and marlin. Limit the amount of tuna you eat to no more than two tuna steaks a week or four medium-size cans of tuna a week. This is because of the levels of mercury in these fish, which can harm a baby's developing nervous system.
Alcohol: The Department of Health recommends that women completely avoid alcohol during pregnancy. However, recent advice from the National Institute for Health and Clinical Excellence (NICE), is slightly less prescriptive, advising that pregnant women should limit their alcohol intake to less than 1.5 units per day and, if possible, avoid alcohol completely in the first three months.