Caffeine is found in varying quantities in tea, coffee, cocoa, chocolate, and soda drinks.
When consumed during pregnancy, caffeine tends to stay on much longer in the body due to the decreased activity of the liver enzyme.
The caffeine-induced increase in serotonin, adrenaline, and dopamine interferes with the blood flow in the placenta and also hampers the transplacental nutrient support to the foetus. (4)
Caffeine and its metabolites can easily cross over the placental barrier. As the foetal liver is still immature, caffeine excretion is delayed. (5)
The fact that caffeine can easily be transmitted across the placenta can be established through the detection of caffeine in the urine, umbilical cord, amniotic fluid, and plasma of foetuses. (6)
In a dose-response analysis, it was found that for every 100 mg of caffeine consumed in a day during pregnancy, there is a corresponding 3% increase in the odds of the child being born with a Low Birth Weight [LBW]. (7)
Infant LBW is implied a birth weight lesser than 2,500 grams. Infant LBW is a well-established risk factor associated with various adult diseases, such as obesity, diabetes mellitus, and hypertension. (8)
Exposure to alcohol has adverse effects on the brain development of the foetus. The adverse effects of alcohol last throughout pregnancy.
When a foetus in the womb is exposed to alcohol, the foetus can develop a wide range of abnormalities, collectively known as Foetal Alcohol Spectrum Disorders [FASD]. (9)
Generally, pregnant women around the world are advised to stay away from alcohol during their pregnancy. In a survey conducted on 1,500 women, it was found that 85% altered their alcohol consumption on learning of their pregnancy. (10) Foetal well-being was cited as the main reason behind the women making the change.
As per the National Center for Biotechnology Information [NCBI], "there is no known safe level of alcohol consumption during pregnancy". (11)
Raw sprouts feature among the list of harmful substances to consume during pregnancy. The humid environment required for sprouting is also a favourable environment for the growth of Salmonella.
While Salmonella thrives in humidity and can be commonly found in raw spouts, it is very difficult to wash it off as well.
Health Canada and the Public Health Agency of Canada have laid down various dietary recommendations for helping pregnant women meet their increased calorific as well as nutrient needs. (12) Additional recommendations for pregnant women include increasing the water intake along with avoiding foods commonly associated with food-borne illnesses.
As per the guidelines issued by Health Canada and the Public Health Agency of Canada, things to be avoided by pregnant women in their diet include raw sprouts, raw eggs, unpasteurised products, and undercooked fish and meat. (13)
Consumption of unpasteurised food products during pregnancy can be harmful both for the mother as well as the foetus in her womb. Unpasteurised milk, fruits juices and cheese are prone to bacterial contamination that can come about at the time of collection or during storage.
Raw milk and raw milk products are a source of bacterial infections that can be attributed to different virulent pathogens, such as E. coli, Salmonella, Listeria etc. (14)
Bacterial infections contracted by the mother during pregnancy can have serious and even life-threatening consequences for an unborn baby.
Generally, pregnant women should best avoid consuming unpasteurised milk and dairy products, smoked fish, deli meats, soft cheeses [pasteurised and unpasteurised], raw and undercooked eggs, raw fish, shellfish etc. (15)
Nutrition - both before and during pregnancy - can have long-lasting effects on maternal as well as neonatal health outcomes.
Consumption of ample fruits, whole grains, lean meats, and vegetables is usually recommended during pregnancy.
Similarly, a limited consumption of alcohol, caffeine, as well as foods high in saturated fat is generally advised for pregnant women.
Evidence has emerged establishing the fact that consumption of foods high in sugar, saturated fat and sodium while pregnant can be especially harmful to pregnant women as well as their unborn babies.
Many of such foods high in sugar, fat and sodium can be categorised as Ultra Processed Foods [UPF]. By a UPF is meant a food substance that is designed to create "durable, accessible, convenient and palatable ready-to-eat or ready-to-heat food products". (16)
Often consumed as snacks in place of home-prepared dishes, such processed food products while being low in whole grains, vitamins and fibre include preservatives, artificial flavours and synthetic colours. These can be particularly harmful for a woman during pregnancy.
Maternal nutritional choices during pregnancy will determine the outcome for both the mother as well as her child. Greater offspring bone size and bone mineral density has been found in pregnancies wherein a prudent maternal diet with a high intake of vegetables, fruits, yoghurt, whole meal bread, rice, and pasta was followed. (17)
The high adherence to a maternal prudent diet also included a low intake of chips, crisps, sugar, white bread, roast potatoes, soft drinks, processed meats, and tinned vegetables. (18)
While eating right is always advisable for promoting optimal health and general well-being, the importance of the right diet can hardly be overstated when you are pregnant. Always remember, whatever you eat when pregnant is shared by your baby in your womb.
Pregnancy is a time to be extra cautious about what you eat. Whatever you consume during pregnancy will effect the baby in your womb. There is a direct link between the diet of an expectant mother and the health of her child.
Studies have revealed that an adequate intake of micronutrients during pregnancy can help in the prevention of various adverse pregnancy outcomes. Supplementation by folic acid prevents neural tube defects in the unborn child. (1)
Based on studies conducted on people suffering from nutrient deficiency, it has been found that nutrients like iron, iodine, proteins, Vitamin A, selenium, long-chain polyunsaturated fatty acids, zinc, and folate are essential for the development of the brain and cognitive function in the foetus. (2)
Multiple observational studies have revealed that a mixed diet rich in vegetable and fruits and containing fish decreases the risk of preterm delivery and gestational diabetes. (3)
While there are many recommended foods for a woman to include in her diet while pregnant, there are also certain foods that are best avoided during pregnancy.
Let us take a look a look at the top five things to avoid consuming when you are pregnant.