Caffeine has been shown to affect mood, stamina, the cerebral vascular system, and gastric and colonic activity. But experts say that caffeine may not be for pregnant women since excess of it can hinder the development of unborn babies SADE OGUNTOLA writes.
A morning cup of coffee or a can of energy drink might help a person manage sleep deprivation, but pregnant women need to avoid foods and drinks that contain caffeine for the sake of their baby’s health and development.
In a new study, researchers from Wuhan University in China discovered that high consumption of caffeine during pregnancy could increase the risk of liver disease in offspring and lower birth weights.
While a baby is still developing in the womb, mothers’ diet is very important, especially considering that some of the foods and drinks that adults consume can be very detrimental to their baby’s health and development later on in life.
For this study, the researchers monitored pregnant rats that were given high and low doses of caffeine. A high dose was equivalent to six to nine cups of coffee, and a low dose was equal to two to three cups of coffee.
Caffeine is able to freely pass the placental barrier in the same way that nutrients or oxygen can. During pregnancy, caffeine clearance from the mother’s blood slows down significantly.
The researchers examined the liver function and hormone levels of the rats’ offspring. Overall, caffeine intake correlated with higher stress and growth hormone levels in a manner that can impair the growth and development of the unborn baby.
The results, they suggested indicated that caffeine intake in pregnancy causes an excess of stress hormone activity in the mother, which inhibits the liver hormone insulin like growth factor (IGF-1) for liver development before birth.
The study was published in the Journal of Endocrinology theories that this added stress on the liver during development and could make the liver disease more likely to develop during adulthood.
Although these findings still need to be confirmed in people, the researchers suggested based on the study that caffeine is not good for babies and recommend that women should avoid caffeine during pregnancy.
The team investigated the effects of low (equivalent to two to three cups of coffee) and high doses (equivalent of six to nine cups of coffee) caffeine, given to pregnant rats, on liver function and hormone levels of their offspring.
Certainly, the amount of caffeine in a cup of coffee will vary depending on the type of coffee and how it’s brewed. The coffee at a restaurant or coffee shop, for example, can range from about 100 mg for a small cup to over 400 mg for a large cup, depending on the brand and the brew.
Also, decaffeinated doesn’t mean caffeine-free. A 16-ounce cup of brewed decaffeinated coffee typically contains about 12 to 25 mg of caffeine.
Dr Akinlolu Adepoju, a pediatrician at the University College Hospital (UCH), Ibadan, Oyo State stated that consuming too much of caffeine during pregnancy is dangerous, given that it can also affect the unborn baby.
According to him, “Everything taken by mouth, inclusive of caffeine, is broken down in the liver. So if they are harmful, they can injure the liver. This might accelerate the development of liver disease later in the child.”
Previous studies in the journal, BMC Medicine has indicated that caffeine intake of 300 mg/day or more in pregnant women, which is approximately two to three cups of coffee per day can result in lower birth weights of their children, regardless of whether the mothers smoked or not.
Babies born small for their age are more likely to develop serious short- and long-term health problems.
A group of researchers from the Norwegian Institute for Public Health had evaluated the effects of consuming caffeine during pregnancy in 60,000 pregnancies. They collected information about the mothers’ diets and birth details over a 10-year period.
They also monitored how much caffeine the mothers consumed, considering a variety of different sources, such as coffee, tea, soft drinks, chocolate and other foods containing cocoa.
For every 100mg of caffeine consumed, the birth weight went down by about 21 to 28 grams and the baby due date (gestational period) is lengthened by five hours. Interestingly, if the caffeine came from coffee, the baby due date increased by eight hours for every 100mg consumed.
Of course, the researchers reasoned that the increased baby’s due date that is associated with coffee consumption could either have been due to another substance in coffee, or possibly there was something unique in the behaviours of the coffee drinkers that were not found in those who only drank teas.
Also, animal studies, although likely in humans, have further suggested that caffeine consumption may have more detrimental long-term effects on liver development with increased susceptibility to non-alcoholic fatty liver disease, a debilitating condition normally associated with obesity and diabetes.
The World Health Organisation (WHO) currently recommends that pregnant women consume no more than 300mg of caffeine per day – the amount contained in around two cups of medium strength, coffee is to reduce the risk of miscarriage and low birth weight babies.
A previous study carried out on mice, although plausible in humans, which was published in The FASEB Journal, found that an equivalent of two cups of coffee in pregnancy could be enough to affect the heart function of offspring throughout their lives.
But Dr Adebukola Adesina, consultant obstetrics and gynecologist, University College Hospital (UCH), Ibadan, Oyo State, said pregnant women are only told to take coffee in moderation because everything a mother does have some form of effect on the unborn baby.
According to Dr Adesina, “if we say that pregnant women should not take coffee because it contains caffeine, then it means that they should not take cola drinks, cocoa products or even tea because it also contains caffeine. So, everything should be in moderation that is what we always teach.
“Yes, excessive intake of caffeine can lead to a low birth weight baby. But I am not sure about the liver case, but it may lead to low birth weight. Like every other thing in pregnancy, it should not be excessive; it should be in moderation.”
Also, energy drinks are not recommended during pregnancy as they may contain high levels of caffeine, and other ingredients not recommended for pregnant women.
Some studies on animals have found that extremely high doses of caffeine are teratogenic — they can cause mutations in the DNA of a fetus, leading to miscarriage. However, it is not clear what level of caffeine, if any, would cause this effect on humans.
According to a survey from Consumer Reports, an energy drink can contain up to 242 milligrams of caffeine per serving, compared to 100 milligrams per 8 ounces of regular coffee.
The American Pregnancy Association says that caffeine can cross the placenta to unborn baby, who cannot fully metabolise the compound, and interfere with her sleep patterns.
In fact, labels on energy drinks contain warnings that state “Not recommended for children, people sensitive to caffeine, pregnant women, or women who are nursing.”
Also, caffeine slightly increases blood pressure, heart rate and the amount of urine the body makes. It can make one feel jittery, have indigestion or have trouble sleeping. Increased sensitivity to caffeine during pregnancy also occurs because it may take a longer time to clear it from the body than if there is no pregnancy.