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Evidence is building that caffeine should be avoided during pregnancy because it harms the developing baby. A recent study found when caffeine (coffee!) is consumed during pregnancy, then structural changes occur in the brain of the developing baby. These changes can be seen years later in brain scans, and these appear to result in behavioral changes in the children. The minimal, but noticeable behavioral changes were behavioral issues, attention difficulties, and hyperactivity.

The Univ. of Rochester School of Medicine and Dentistry researchers  found subtle changes in brain pathways ("alteration of the microstructure of critical fiber tracts") between brain regions that could be seen in the children at age 9 to 10 years. They analyzed brain scans (from MRIs) of 9157 children, of which 4,135 had mothers that reported consuming caffeine more than once a week.

Other studies find that health problems associated with caffeine (coffee) intake during pregnancy are miscarriage, stillbirth, low birth weight and/or small for gestational age, and childhood leukemia. There is a dose-response effect - the more caffeine is ingested, the more negative health effects.

Other human studies looking at this issue are observational, but negative health effects are supported by animal research going back more than four decades. Caffeine crosses the placenta and goes to the baby. Negative health effects occur because the fetus can not clear the caffeine well because it lacks an enzyme that metabolizes caffeine.

Unfortunately, medical guidelines in both the US and Europe are that moderate (up to 200 mg) ingestion of caffeine during pregnancy is OK, which means about 2 cups of regular coffee a day. Since studies show it's not OK, it's time to revise the guidelines!

From Science Daily: Brain changed by caffeine in utero

New research finds caffeine consumed during pregnancy can change important brain pathways that could lead to behavioral problems later in life. Researchers in the Del Monte Institute for Neuroscience at the University of Rochester Medical Center (URMC) analyzed thousands of brain scans of nine and ten-year-olds, and revealed changes in the brain structure in children who were exposed to caffeine in utero.  ...continue reading "Avoid Caffeine During Pregnancy"

Pregnant women receive all sorts of advice on what to do or not do during pregnancy. For years medical guidelines in both the US and Europe have been that moderate (up to 200 mg) ingestion of caffeine during pregnancy is OK, which means about 2 cups of regular coffee a day.

However, a recent review of studies by Reykjavik University Professor Jack E. James found that ingesting caffeine during pregnancy is linked to health problems and that there is no safe level during pregnancy. In other words,  caffeine and caffeinated beverages should be avoided during pregnancy and when trying to conceive.

Health problems associated with caffeine intake during pregnancy are miscarriage, stillbirth, low birth weight and/or small for gestational age, childhood leukemia, and childhood overweight and obesity. Studies typically found a dose-response effect - the more caffeine is ingested, the more negative health effects.

Human studies looking at this issue are observational, but negative health effects are supported by animal research going back more than four decades. Caffeine crosses the placenta and goes to the baby. Negative health effects occur because the fetus can not clear the caffeine well because it lacks an enzyme that metabolizes caffeine.

Professor James points out that the industry established and funded the group ILSI (International Life Sciences Institute) which successfully fought any FDA warnings about caffeine and pregnancy, and which attacked any research suggesting it could be harmful to pregnancy or the fetus. [Why am I not surprised about the success of the industry group? And that they published their own "research" showing caffeine was benign in response to scientific research showing negative health effects.]

Excerpts from Science Daily: No safe level of caffeine consumption for pregnant women and would-be mothers

Women who are pregnant or trying to conceive should be advised to avoid caffeine because the evidence suggests that maternal caffeine consumption is associated with negative pregnancy outcomes and that there is no safe level of consumption, finds an analysis of observational studies published in BMJ Evidence Based Medicine.   ...continue reading "Avoid Consuming Caffeine During Pregnancy"

Pregnant women have been advised to keep their consumption of coffee and other caffeinated beverages (tea, sodas, cocoa, energy drinks), and chocolate containing foods to a minimum for decades. Currently the American College of Obstetrics recommends that women consume less than 200 mg of caffeine (from any source) per day during pregnancy. This is less than 2 cups of regular coffee  or 4 cups of regular black tea. But a recent  study's findings suggest that the levels should be kept much lower.

The study of 941 mother/baby pairs in Ireland found that each 100 mg increase of caffeine per day was associated with a lower birth weight, shorter length of pregnancy (gestational age), shorter birth length of the baby, and smaller head circumference of the baby at birth. The strongest associations between those who consumed the most caffeine (when compared to those who consumed the least) was with lower birth weight.

The researchers think this occurs because caffeine crosses the placenta easily, but during pregnancy there is a slowed metabolism of caffeine (so it takes longer to get it out of the body). Similar results have been found in other recent studies. [On the other hand, for not pregnant women - coffee and tea are linked to all sorts of health benefits - here, here.]

From Medical Xpress: Caffeinated beverages during pregnancy linked to lower birth weight babies

...continue reading "Keep Caffeine To A Minimum During Pregnancy"

Two more studies find that drinking coffee is associated with health benefits, which is good news for coffee drinkers. The first study found an association of daily coffee drinking (both caffeinated and decaffeinated) and lower risk of premature mortality (early death) among half a million United Kingdom residents - as compared to those who don't drink coffee. Studies finding an association with daily coffee consumption and health benefits (e.g. lower risk of type 2 diabetes, some cancers, and death from heart disease and stroke) are really adding up. The studies generally find the positive health effects to be dose dependent, usually up to about 4 cups of coffee.

The second study found that in mice, an amount of caffeine equivalent to four cups of coffee was beneficial to mitochondria, improved mitochondria-dependent processes, and protected heart cells from damage. The researchers thought that the same process occurs in humans. What are mitochondria?Mitochondria are the “powerhouses of the cell”. Mitochondria are organelles found in the cells of every complex organism. They produce about 90% of the chemical energy that cells need to survive.

From Medical Xpress: Fresh grounds for coffee: Study shows it may boost longevity

Go ahead and have that cup of coffee, maybe even several more. New research shows it may boost chances for a longer life, even for those who down at least eight cups daily. In a study of nearly half-a-million British adults, coffee drinkers had a slightly lower risk of death over 10 years than abstainers ...continue reading "More Good News About Coffee"

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Should the results of this study determine what kind of coffee one drinks? Does it really make a difference? Eh...Not for me (because all coffee seems to be beneficial), but it might for you.

Studies show that daily drinking of coffee appears to have health benefits. Studies have linked coffee consumption with lower rates of cancer (here and here), cardiovascular disease, and diabetes. Coffee contains beneficial chemicals (such as caffeine and chlorogenic acid) that are antioxidant and anti-inflammatory, and could help fight chronic inflammatory diseases. It turns out that how much coffee beans are roasted changes how much chlorogenic acid they contain, but the amount of caffeine basically stays the same among the different roasting levels.

Researchers in Korea compared the caffeine and chlorogenic acid components of Arabica coffee beans at different roasting levels: Light, Medium, City, and French roast. They then tested various protective antioxidant and anti-inflammatory properties of the different coffee extracts in various "cell models" (meaning in the lab, not on real people). They found that chlorogenic acid levels were higher in light roasted coffee extract than the other roasted groups, and also light roasted coffee extract had the highest antioxidant activity. The results found that increasing degrees of roasting reduced antioxidant and anti-inflammatory activities.

From the Journal of Medicinal Food: Cellular Antioxidant and Anti-Inflammatory Effects of Coffee Extracts with Different Roasting Levels

During roasting, major changes occur in the composition and physiological effects of coffee beans. In this study, in vitro antioxidant effects and anti-inflammatory effects of Coffea arabica green coffee extracts were investigated at different roasting levels corresponding to Light, Medium, City, and French roast. Total caffeine did not show huge difference according to roasting level, but total chlorogenic acid contents were higher in light roasted coffee extract than other roasted groups. In addition, light roasted coffee extract had the highest antioxidant activity.... The expression of mRNA for tumor necrosis factor-alpha and interleukin-6 was decreased in cells treated with the coffee extracts and the expression decreased with increasing roasting levels. These data suggest that coffee has physiological antioxidant and anti-inflammatory activities and these effects are negatively correlated with roasting levels in the cell models.

Coffee is one of the most popular beverages worldwide. Increasing consumption of coffee is related to the pleasing taste and aroma, as well as its physiological effects. Coffee is proposed to exert beneficial effects against cancer, cardiovascular disease, obesity, and diabetes. Coffee contains phenolic compounds such as caffeic acid, chlorogenic acid, ferulic acid, vanillic acid, and other phytochemicals. The quality of coffee is significantly related to the roasting process.... During roasting, there are numerous changes in coffee bean compound profiles and the aroma is increased. Major changes in coffee bean composition occur during roasting as a result of the Maillard reaction..... Roasting markedly affects chlorogenic acid, leading to hydrolysis of chlorogenic acid. New compounds are formed during the roasting process; one of these is melanoidin. Its formation might alter the overall antioxidant capacity of coffee beans after roasting.

Coffee is a rich source of antioxidants that may contribute to prevention of oxidative stress-related diseases. The antioxidant properties of coffee may reflect the presence of both phenolic and nonphenolic bioactive compounds, such as caffeine and chlorogenic acids. Previous studies have shown that coffee has protective effects against oxidation and DNA damage in human cell models and has been shown to possess an in vitro antioxidant activity that lessens lipid peroxidation and neoplastic activity. 

Caffeine is the major component in coffee extract and has antioxidant property. Chlorogenic acid is another well-known efficient antioxidant in coffee extract; it was highest in Light roast coffee extract and highest with low roasting temperature and lowest in Dark roasted extract. Carbohydrates, protein, and chlorogenic acid are all decreased in coffee during the roasting process.... Caffeine contents showed no differences among roasting levels, but chlorogenic acid content decreased as roasting degree increased..... The effect of coffee roasting on the antioxidant properties of coffee extracts was investigated in several earlier studies; antioxidant capacity decreased in Dark roast coffee. The antioxidant property of coffee extracts prepared with different roasting levels was also determined in this study. The best antioxidant activity was evident in Light roast coffee extract and the lowest in French roast coffee.

A University of Georgia review study of the research literature shows that drinking coffee (instead of a caffeine supplement) improves athletic endurance performance. Also, that caffeine from coffee has ergogenic benefits—that it enhances physical performance. More beneficial effects of coffee! From Medical Xpress:

Coffee may improve athletic endurance performance, review finds

The caffeine in a morning cup of coffee could help improve athletic endurance, according to a new University of Georgia review study....To research the issue, Higgins reviewed more than 600 scholarly articles and screened them for those that focused only on caffeinated-coffee conditions, measured the caffeine dose and measured an endurance performance. Of these, nine randomized control trials specifically used coffee to improve endurance."Previous research has focused on caffeine itself as an aid to improve endurance," Higgins said.

 Looking at the nine trials, Higgins found that between 3 and 7 milligrams per kilogram of body weight of caffeine from coffee increased endurance performance by an average of 24 percent. The amount of caffeine in a cup of coffee can vary from 75 mg to more than 150, depending on the variety and how it's roasted and brewed. 

In the nine trials, participants either cycled or ran after drinking coffee. They then exercised vigorously and the results were measured. In a majority of cases, endurance was noticeably improved after the use of coffee.When researching the effects of caffeine from coffee, Higgins found two important discoveries: that caffeine from coffee has ergogenic benefits—that it enhances physical performance—and that more research is needed on the use of caffeine from coffee versus pure caffeine use.

"While there is a lack of high-quality research on coffee as a source of caffeine, there is an abundance of research on pure caffeine," he said. "It's surprising how little we know about caffeine from coffee when its endurance effects could be just as beneficial as pure caffeine."

Higgins said that coffee shouldn't be dismissed as less beneficial for endurance. He found that coffee appears to be just as helpful as taking caffeine in the form of powder or tablets.... Higgins says that more research is needed before giving official recommendations to athletes, especially since the amount of caffeine in a cup of coffee can vary depending on how it's prepared.

More good news for coffee drinkers! A number of studies have found that coffee drinking is protective against breast cancer (coffee inhibits the growth of tumors), but now research finds it is also protective against breast cancer recurring. The beneficial effects are seen with 2 or more cups of coffee per day. Other studies have found that lifestyle changes (such as weight loss, healthy eating, and exercise) are linked to lower rates of recurrence, but apparently coffee drinking can also be added to the list. This research found that not only is coffee drinking linked to smaller tumors in the first place, but it is also linked to lower rates of recurrence in women also taking tamoxifen. The researchers said: "In summary, this study shows inhibitory effects by caffeine and caffeic acid on breast cancer cell growth." Both caffeine and caffeic acid are present in coffee. From Science Daily:

Coffee protects against breast cancer recurrence, detailed findings confirm

A number of research studies have shown that coffee helps to protect against breast cancer. A new study led by Lund University, has confirmed that coffee inhibits the growth of tumors and reduces the risk of recurrence in women who have been diagnosed with breast cancer and treated with the drug tamoxifen.

The study, which is a follow-up of the results the researchers obtained two years ago, was carried out at Lund University and Skåne University Hospital, in collaboration with researchers in the UK. "Now, unlike in the previous study, we have combined information about the patients' lifestyle and clinical data from 1090 breast cancer patients with studies on breast cancer cells. The study shows that among the over 500 women treated with tamoxifen, those who had drunk at least two cups of coffee a day had only half the risk of recurrence of those who drank less coffee or none at all," explain researchers Ann Rosendahl and Helena Jernström, who obtained the results in collaboration with Jeff Holly and his research team at University of Bristol.

"The study also shows that those who drank at least two cups of coffee a day had smaller tumors and a lower proportion of hormone-dependent tumors. We saw that this was already the case at the time of diagnosis."

In the cell study, the researchers looked more closely at two substances that usually occur in the coffee drunk in Sweden -- caffeine and caffeic acid.

"The breast cancer cells reacted to these substances, especially caffeine, with reduced cell division and increased cell death, especially in combination with tamoxifen. This shows that these substances have an effect on the breast cancer cells and turn off signalling pathways that the cancer cells require to grow.

Researchers found that caffeine enhances memory.From Science Daily:

It's All Coming Back to Me Now: Researchers Find Caffeine Enhances Memory

Michael Yassa, assistant professor of psychological and brain sciences in the Krieger School of Arts and Sciences at Johns Hopkins, and his team of scientists found that caffeine has a positive effect on long-term memory in humans. Their research, published by the journal Nature Neuroscience, shows that caffeine enhances certain memories at least up to 24 hours after it is consumed.

According to the U.S. Food and Drug Administration, 90 percent of people worldwide consume caffeine in one form or another. In the United States, 80 percent of adults consume caffeine every day. The average adult has an intake of about 200 milligrams -- the same amount used in the Yassa study -- or roughly one strong cup of coffee or two small cups of coffee per day.