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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"

Great news coffee drinkers! Another study - this time a large analysis of over 200 studies found that coffee consumption is linked to many health benefits. The best results were from drinking 3 to 4 cups of coffee daily (as compared to none), with a reduction in "all cause" mortality (death from any cause), and cardiovascular disease and death.

They also found a lower risk of cancer in general, and with a lower risk of several specific cancers (endometrial, prostate, melanoma, non-melanoma skin cancer, liver cancer) and neurological (Parkinson's disease, Alzheimer's disease, and depression), metabolic (including type 2 diabetes, metabolic syndrome), and liver conditions.

However, during pregnancy high coffee consumption (as compared to low or no consumption) was associated with low birth weight, preterm birth in the first and second trimester, and pregnancy loss. The researchers also found an association between coffee drinking and a small risk of fracture in women, but not in men. Decaffeinated coffee seemed to have many of the same benefits as caffeinated coffee - especially at 2 to 4 cups a day.

[UPDATE: A 2020 review of studies 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.]

Excerpts from Science Daily:

Three to four cups of coffee a day linked to longer life

Drinking coffee is "more likely to benefit health than to harm it" for a range of health outcomes, say researchers in The BMJ today. They bring together evidence from over 200 studies and find that drinking three to four cups of coffee a day is associated with a lower risk of death and getting heart disease compared with drinking no coffee. Coffee drinking is also associated with lower risk of some cancers, diabetes, liver disease and dementia. However, they say drinking coffee in pregnancy may be associated with harms, and may be linked to a very small increased risk of fracture in women.

The included studies used mainly observational data, providing lower quality evidence, so no firm conclusions can be drawn about cause and effect, but their findings back up other recent reviews and studies of coffee intake. As such, they say, excluding pregnancy and women at risk of fracture, "coffee drinking appears safe within usual patterns of consumption" and they suggest that coffee could be safely tested in randomised trials.

To better understand the effects of coffee consumption on health, a team led by Dr Robin Poole, Specialist Registrar in Public Health at the University of Southampton, with collaborators from the University of Edinburgh, carried out an umbrella review of 201 studies that had aggregated data from observational research and 17 studies that had aggregated data from clinical trials across all countries and all settings. (Original study.)

It seems like I can't stop writing about coffee (here and here). Coffee drinkers rejoice: another study (presented at the European Society of Cardiology) finds health benefits from drinking several cups of coffee daily. This study, like other previous studies, found an inverse relationship between drinking coffee and early death ("all-cause mortality") - meaning the more one drinks coffee, the less likely one is to have a premature death. The biggest effect was in drinking 4 cups daily in people aged 45 and older! It was an observational study, so can't prove it definitely - can only say there's an association. But still... it's looking good. From Medical Xpress:

Higher coffee consumption associated with lower risk of death

Higher coffee consumption is associated with a lower risk of death, according to research presented today at ESC Congress. The observational study in nearly 20,000 participants suggests that coffee can be part of a healthy diet in healthy people. 

The purpose of this study was to examine the association between coffee consumption and the risk of mortality in a middle-aged Mediterranean cohort. The study was conducted within the framework of the Seguimiento Universidad de Navarra (SUN) Project, a long-term prospective cohort study in more than 22,500 Spanish university graduates which started in 1999. This analysis included 19,896 participants of the SUN Project, whose average age at enrollment was 37.7 years old. .... Patients were followed-up for an average of ten years. 

During the ten year period, 337 participants died. The researchers found that participants who consumed at least four cups of coffee per day had a 64% lower risk of all-cause mortality than those who never or almost never consumed coffee. There was a 22% lower risk of all-cause mortality for each two additional cups of coffee per day.

The researchers examined whether sex, age or adherence to the Mediterranean diet had any influence on the association between baseline coffee consumption and mortality. They observed a significant interaction between coffee consumption and age. In those who were at least 45 years old, drinking two additional cups of coffee per day was associated with a 30% lower risk of mortality during follow-up. The association was not significant among younger participants.

Once again several studies found health benefits associated with drinking coffee daily - this time "reduced risk of death" in 2 studies, and in one study a reduced risk of gallbladder cancer.

Just keep in mind that the studies found associations, but did not establish that drinking coffee caused X (reduced risk of death) - so perhaps coffee drinkers differ in some still unknown way from non-coffee drinkers. But...so many studies are piling up showing an association with health benefits that it looks likely that it is actually the coffee causing the benefits. Both decaffeinated and regular coffee seem beneficial, and it doesn't matter how it is prepared (e.g., espresso, drip, cappuccino). (Earlier posts about coffee - here, here, here)

In the one study higher consumption of coffee was associated with a lower risk of death from heart disease, cancer, stroke, diabetes, and kidney disease in African Americans, Japanese Americans, Latinos, and whites. People who consumed a cup of coffee a day (decaffeinated or regular) were 12 percent less likely to die compared to those who didn't drink coffee, and those who drank two to three cups a day had an 18 percent reduced chance of death.

The conclusion of the other study of over half million adults in 10 European countries was similar: coffee drinking was associated with lower risk for death from "all causes", especially from circulatory diseases and diseases related to the digestive tract. This association held up among all the countries. The highest levels of consumption  group (3 cups or more of coffee per day)  had the lowest risk of death - as compared to those drinking none or less than 1 cup of coffee per day. However, the one negative result from drinking more than 3 cups of coffee daily was an increase in risk for ovarian cancer mortality in women (but only when compared to coffee non-drinkers).

From STAT News: Drink coffee? It won’t hurt you, and may reduce your risk of an early death

Good news, coffee drinkers: A couple of massive new studies that looked at hundreds of thousands of people for about 16 years finds that a few cups of coffee a day won’t hurt you and could lower your risk of dying prematurely. The studies reinforce previous findings that drinking an 8-ounce cup of joe (or three) won’t hurt you, but the authors of the new works and other experts say caveats abound.

Murphy told STAT his is the largest study on coffee and mortality to date. In the study, researchers with the WHO’s International Agency for Research on Cancer and Imperial College London tracked 521,000 adults from 10 European countries who self-reported their coffee consumption over an average of 16 years.... In investigating more than 40,000 deaths from this group, the team found that participants who fell into the highest 25 percent of coffee consumers had a lower risk of death due to any cause compared to non-coffee drinkers. They saw a reduced risk of early death by diseases related to the digestive and circulatory systems. The researchers also discovered a link between higher coffee consumption and lower risk of early death by lung cancer in men. And they also looked at suicide — completed suicides were lower for coffee drinkers, but only in men. [Original study.]

In a second study of 180,000 people tracked for an average of 16 years, University of Southern California investigators found drinking one to six cups of coffee per week led to a decreased risk of early death. The study was focused on non-white populations, andtheir findings proved consistent for coffee drinkers across racial and ethnic groups. One of the USC study’s senior authors, V. Wendy Setiawan... said coffee consumption may be linked a lower risk of early death for people with heart disease, cancer, chronic lower respiratory disease, stroke, and kidney disease.Drink one cup per day, and the risk of dying early from those diseases decreases by 12 percent, she said. [Original study.]

This 2016 study is from Medscape: Coffee Consumption and Risk of Gallbladder Cancer in a Prospective Study

Evidence indicates that coffee consumption may reduce the risk of gallstone diseasewhich is strongly associated with increased risk of gallbladder cancer. The association between coffee consumption and gallbladder cancer incidence was examined in a prospective cohort study of 72,680 Swedish adults (aged 45 − 83 years) who were free of cancer and reported their coffee consumption at baseline.....  In conclusion, coffee consumption was observed to be associated with a reduced risk of gallbladder cancer. A potential protective association between coffee consumption and risk of gallbladder cancer may be mediated via reduced gallstone formation or through other mechanisms such as reduction of oxidative damage and inflammation and regulation of DNA repair, phase II enzymatic activity, apoptosis, angiogenesis, and metastasis.

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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.

One of the dreaded afflictions of getting older is age-related macular degeneration (AMD), which is a leading cause of vision loss in Americans 60 years and older. It has no cure. Thus this study finding that eating a Mediterranean diet, and especially lots of fruit, was associated with a lower risk of macular degeneration was welcome news. They also found a protective effect from drinking caffeinated beverages - about 78 mg of caffeine per day (about one cup of coffee or one shot of espresso). A Mediterranean diet stresses eating fruits, vegetables, nuts, whole grains, legumes, fish, seeds, and olive oil. From Science Daily:

Fruit-rich Mediterranean diet with antioxidants may cut age-related macular degeneration risk by more than a third

People who closely follow the Mediterranean diet -- especially by eating fruit -- may be more than a third less likely to develop age-related macular degeneration, a leading cause of blindness, according to a study presented at AAO 2016, the 120th annual meeting of the American Academy of Ophthalmology. The study is the first to identify that caffeine may be especially protective against AMD.

Many studies have confirmed the health benefits of the Mediterranean diet, which emphasizes eating fruits, vegetables, whole grains, legumes, nuts, healthy fats and fish, and limiting red meat and butter. The diet has been shown to improve heart health and reduced risk of cancer, but there has been little research on whether its benefits can extend to eye disease. To determine this, researchers studied a Portuguese population to see whether adherence to the diet impacted people's risk of AMD. Their findings revealed a significant reduction in risk in those who ate a Mediterranean diet most frequently, and particularly among those who consumed more fruit and caffeine.

Researchers at the University of Coimbra in Portugal studied 883 people age 55 or older in the central region of the country between 2013 and 2015. Of those, 449 had AMD in its early stages before vision loss, and 434 did not have AMD. Researchers assessed their diets based on a questionnaire asking how often they ate foods associated with the Mediterranean diet. The more they ate foods associated with the diet, the higher the score, from 0-9. Those who closely followed the diet scored a 6 or greater. Their findings were as follows:

Higher diet adherence scores meant lower AMD risk Of those who did not closely follow the diet (scored below a 6), 50 percent had AMD. Of those who did closely follow the diet (scored 6 or above), only 39 percent had AMD. This represents a 35 percent lower risk compared to those who did not adhere to the diet.

Fruits were especially beneficial Researchers analyzed consumption of foods and found that people who consumed higher levels of fruit were significantly less likely to have AMD. Of those who consumed 150 grams (about five ounces) or more of fruit a day: 54.5 percent did not have AMD and 45.5 percent had AMD. Overall, people who ate that much fruit or more each day were almost 15 percent less likely to have AMD, based on an odds ratio calculation.

Caffeine and antioxidants also were protective Researchers used a computer program to analyze the participants' consumption of micronutrients, according to their answers on the questionnaire. They found higher consumption of antioxidants such as caffeine, beta-carotene and vitamins C and E was protective against AMD. Of those who consumed high levels of caffeine (about 78 mg a day, or the equivalent of one shot of espresso): 54.4 percent did not have AMD and 45.1 percent had AMD....The researchers opted to look at caffeine because it is a powerful antioxidant that is known to be protective against other conditions, such as Alzheimer's disease.

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.

Research finding benefits from various foods. From Science Daily:

Drinking decaf or regular coffee maybe good for the liver

Researchers report that decaffeinated coffee drinking may benefit liver health. Results show that higher coffee consumption, regardless of caffeine content, was linked to lower levels of abnormal liver enzymes. This suggests that chemical compounds in coffee other than caffeine may help protect the liver. Previous studies found that coffee consumption may help lower the risk of developing diabetes, cardiovascular disease, non-alcoholic fatty liver disease, cirrhosis, and liver cancer.

From Science Daily:

Did fruit contribute to Apple's success?

Steve Jobs swore by a fruit diet, as he believed it improved his ideas. And he wasn't wrong: food with high levels of tyrosine, like bananas, peaches and almonds, allow us to think harder and more creatively.

The researchers found that the test subjects who drank orange juice with added tyrosine were better at solving puzzles than those who were administered a placebo. Tyrosine is an amino acid that increases the production of dopamine in the brain, which positively influences our ability to think creatively. It can be found in various kinds of fruit, but also in soybeans, spinach, eggs and cottage cheese.

Done in mice, but interesting. And think of all the people who have promoted grapefruit diets over the years. From Science Daily:

Grapefruit juice stems weight gain in mice fed a high-fat diet, study finds

Mice fed a high-fat diet gained 18 percent less weight when they drank clarified, no-pulp grapefruit juice compared with a control group of mice that drank water, a new study demonstrated. Juice-drinking mice also showed improved levels of glucose, insulin and a type of fat called triacylglycerol compared with their water-drinking counterparts.

Excerpts from an article by Jane Brody in the NY Times:

Beating Back the Risk of Diabetes

This year, nearly two million American adults and more than 5,000 children and adolescents will learn they have a potentially devastating, life-shortening, yet largely preventable disease: Type 2 diabetes. They will join 29.1 million Americans who already have diabetes.

Diabetes and its complications are responsible for nearly 200,000 deaths a year; the fatality rate among affected adults is 50 percent higher than among similar people without diabetes. Alarmingly, recent studies even have linked diabetes to an increased risk of dementia and Alzheimer's disease. Even people with above-average blood glucose levels, but not diabetes, have an elevated risk.

The Diabetes Prevention Program study, conducted among about 3,800 people who had pre-diabetes, found that moderate weight loss — an average of 12 pounds —  reduced the odds of progression to diabetes by nearly 50 percent.

An excellent discussion of what is known about the effect on diabetes of various foods and supplements appeared recently in Nutrition Action Healthletter at cspinet.org/iceberg.pdf. Some highlights:

Carbohydrates - breads, grains, cereals, sugary drinks and sweets of all kinds — are most problematic for people with diabetes or at risk of developing it. Carbohydrates are eventually metabolized to glucose, which raises the body’s demand for insulin. Consume less of them in general, and choose whole-grain versions whenever possible.

If you must have sweet drinks, select artificially sweetened ones. In two huge studies of nurses and other health professionals who were followed for 22 years, those who drank one or more sugary soft drinks a day had about a 30 percent higher risk of developing diabetes than those who rarely drank them, even after their weight was taken into account.

But there’s good news about coffee. Two or three cups of coffee (but not tea) a day, with or without caffeine, have been consistently linked to a lower risk of Type 2 diabetes. 

For protein, limit consumption of red meat, especially processed meats like sausages, hot dogs and luncheon meats, which are linked to a higher diabetes risk. Instead, choose fish, lean poultry (skinless and not fried), beans and nuts. Low-fat dairy products, including yogurt, and even fatty ones may lower the risk of diabetes; the reason is unclear.

Most protective are green, leafy vegetables — spinach, chard, kale, collards, mustard greens and even lettuce — as well as cruciferous vegetables like cabbage, broccoli and cauliflower. But all vegetables are good and should fill at least two-thirds of your dinner plate.

The nutrients magnesium and vitamin D are also potentially protective. In fact, the preventive value of leafy greens, whole grains, beans and nuts may lie in their high magnesium content. In a well-designed clinical trial of 32 overweight people with insulin resistance, the prelude to diabetes, blood glucose levels and insulin sensitivity improved in those who took a daily magnesium supplement for six months. Don’t go overboard: More than 350 milligrams of magnesium daily can cause diarrhea. 

Vitamin D, long known to be crucial to healthy bones, may also be helpful. In one study of 92 overweight or obese adults with prediabetes, those who took a supplement of 2,000 international units of vitamin D daily had better function of the pancreatic cells that produce insulin..

Of course, how much you weigh and what you eat are not the only concerns. Regular, preferably daily, physical exercise is a vital component of any prevention and treatment program for Type 2 diabetes, or most any chronic ailment. Weight loss can reduce diabetes risk by about 50 percent, but adding exercise to that can lower the odds by 70 percent, compared with people who remain overweight and inactive, according to a study that followed nearly 85,000 female nurses for 16 years. Women who were active for seven or more hours weekly had half the risk of developing diabetes as did women who exercised only a half-hour a week.