Tag Archives: caffeine

 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.