Bacteria Make Snow And Rain

Scientists in the US have discovered that living organisms like bacteria play an important role in making rain and snow in the atmosphere. The discovery could help researchers understand the role of living organisms in the water cycle and lead to better climate forecasting, and solve problems of water shortage, said the researchers.

The discovery was made by Dr Brent C Christner assistant professor of Biological Sciences at Louisiana State University in Baton Rouge, and colleagues, and is written up in the 29 February issue of Science.

High in the earth's atmosphere, rain and snow clouds gather because of a process called ice nucleation. Small particles and suspensions of liquid and particles, aerosols to be precise, give water molecules a surface to cling to and clump together until eventually they form clouds.

For some time scientists have known about the role played by these various ice nucleators (IN) and how their presence eventually leads to precipitation, but what they did not know much about was where they came from and what they were made of.

Christner and colleagues looked at different types of ice nucleators (INs) at mid and high latitudes and discovered that most of them were biological in origin.

60 to 100 per cent of the INs that were bigger than 0.2 micrometers and working at temperatures higher than minus 7 degrees C, were biological, and many of them were bacteria.

Christner and colleagues said that the earth's atmosphere is full of highly active biological INs that play an important role in the water/precipitation cycle, and also not to be ignored is that they themselves come down in rain and snow.

Christner told the Associated Press that bacteria were by far the most active ice nucleators in nature. He and his colleagues took snow samples in Antarctica, France, Montana (US) and the Yukon (Canada).

They found that in some of the samples 85 per cent of the INs were bacteria. The French samples had the highest concentration of bacterial INs, followed by Montana and the Yukon. Even the samples from Antarctica contained bacteria, but at much lower levels.

Strangely enough, the most common bacteria they found in the samples was Pseudomonas syringae, which infects plants like tomatoes and beans and has been mostly considered a candidate for elimination because of this, but as Christner said to the Associated Press, perhaps that is now not such a good idea.

What would happen to the process of cloud formation if a principal catalyst were to be eliminated? Would it simply be replaced by particles like soot and dust?

An interesting point he raised was what if plants in dry areas infected with Pseudomonas syringae were actually helping to increase the chance of rainfall by putting more INs into the atmosphere?

What science is revealing to us more and more is that the atmosphere is not an "inert" stratum, but a complex biomass intricately interwoven with processes that affect planetary life, such as the water cycle.

The authors suggest that deciphering some of these "feedback" mechanisms between the biosphere and climate could have important implications for climate forecasting and understanding the way that plant pathogens and other microorganisms travel around the globe.

Ten Per Cent Of US Adults Not Getting Enough Sleep, Survey

The US Centers for Disease Control and Prevention (CDC) this week reported the results of a study based on a 2006 survey of four US states that suggests ten per cent of adult Americans are not getting enough daily rest or sleep.

The study is published in the CDC's Morbidity and Mortality Weekly Report (MMWR) dated the 29th of February.

The ten per cent figure comes from a study based on the CDC′s Behavioral Risk Factor Surveillance System (BRFSS), which covered the four states of Delaware, Hawaii, New York, and Rhode Island, and may not be typical of the US as a whole, said the CDC in a press statement.

However, another study carried out by the CDC using data from the National Health Interview Study suggested that the proportion of adults of all ages who report sleeping six hours or less has gone up between 1985 and 2006, which would indicate that perhaps the BRFSS data is probably not too far off the mark.

According to background information in the MMWR report, an estimated 50 to 70 million Americans suffer from sleep disorders and chronic loss of sleep, which leads to health problems such as obesity, depression, smoking, lack of physical activity and too much drinking.

The study's lead author, who is a behavioural scientist at the CDC's Division of Adult and Community Health, Dr Lela R McKnight-Eily, said it was important to gain a better understanding of how sleep affects overall health and that steps should be taken to help people get enough sleep.

"There are very few studies to assess and address sleep insufficiencies; therefore, more needs to done to better understand the problem and to develop effective sleep interventions," said McKnight-Eily.

McKnight-Eily and colleagues analyzed data from the BRFSS 2006 survey. Among the four states, the proportion of adults who reported not getting enough sleep or rest every day in the last 30 days ranged from 8 per cent in Hawaii to 14 per cent in Delaware.

Only one in three adults (29.6 per cent) reported getting enough rest or sleep every day in the past month.

People worried about chronic lack of sleep should be assessed by their doctor and talk about possible treatment, for which there are a range of behavioural and medical options, said McKnight-Eily. Another way would be to stick to a regular sleep pattern and avoid stimulants like caffeine before retiring, she added.

A 2006 report by the Institute of Medicine said work or lifestyle factors are probably to blame. Examples of reasons why people don't get enough sleep or have irregular sleep patterns include shift work, work overload, family demands, late night Internet surfing and TV viewing, and use of caffeine and alcohol.

According to the National Sleep Foundation, most adults need between 7 and 9 hours sleep every night to feel fully rested. Children between 5 and 12 years of age need between 9 and 11 hours, while teenagers need between 8.5 and 9.5 hours, they suggest.

The CDC study also found that the proportion of adults saying they were not getting enough sleep went down with age. They estimated 13.3 per cent of adults in the 18 to 34 bracket reported they were not getting enough rest or sleep every day in the past month compared with only 7.3 per cent aged 55 and over.

This appears contrary to those studies that suggest more older adults have disturbed sleep, but supports other studies that say fewer older adults (who are also more likely to be retired) are bothered by impaired sleep and seem to adapt their perception of what constitutes enough.

A possible limitation of the study was that definitions of enough sleep, and the difference between sleep and rest were not given in the survey, which left it to respondents to decide this for themselves. This subjective self-report method cannot be compared on a like for like basis to more objective studies that count how many hours people sleep every night. However, as a study of perceived lack or sufficiency or sleep, it is revealing.

The timing of this information is no coincidence. Next week, March 3rd to 9th, is US National Sleep Awareness Week, a campaign held every year that coincides with Daylight Saving Time.

Baxter Recalls All Heparin Vial Products

Baxter International Inc announced yesterday, Thursday 28th February, that it was recalling all remaining multi-dose and single-dose heparin sodium and HEP -LOCK heparin flush products now that alternative suppliers are able to meet national demand for them.

Heparin sodium is a vital ingredient in surgical and medical procedures that has been used throughout the US since the 1930s. It is injected into millions of Americans every year to stop potentially fatal blood clots in their veins, arteries and lung. The drug is made from the lining of pig intestines and most of it comes from China.

The announcement was in a statement released by the US Food and Drug Administration on behalf of the drug company.

This follows the recall in January of nine lots of Baxter's heparin sodium injection multi-dose vials as a precautionary measure after hundreds of patients had severe allergic reactions, and also four patients died, after receiving the product. The drug company also stopped making the product pending a fuller investigation.

The FDA has since admitted that a Chinese plant that supplied Baxter with the heparin active ingredient, which is made from pigs' intestines, was not inspected by the agency. The agency said it had confused the supplier with another similarly named Chinese supplier on its database that had already been approved.

The HEP-LOCK heparin flush (used to flush intravenous lines and equipment to prevent blood clots) and single dose heparin sodium vials were not recalled because they had not been linked to the adverse reactions and it was essential to keep supplies of this vital ingredient flowing until the demand could be met by an alternative source.

Baxter produces nearly half the US demand for heparin used in operating rooms, dialysis centers and other critical care areas. Pulling their products before an alternative source was found would have "created more risk to patients requiring heparin therapy than the increased potential for experiencing an adverse reaction", said the FDA.

The agency has concluded there is now sufficient capacity from other suppliers and has given Baxter the go ahead to recall its remaining heparin sodium injection and heparin flush products.

According to Sandra Kweder, deputy director of FDA's Center for Drug Evaluation and Research, the only Baxter products that are still on the market use heparin sourced from a different supplier. These products contain heparin in premixed IV solution bags and have not been associated with adverse events.

Exactly how the patients came to have allergic reactions to the affected products is still a mystery. The FDA has sent two officers to China where an initial investigation found problems linked to incomplete removal of impurities, plant conditions and management of waste.

According to the Washington Post, Michael Rogers, director of the FDA's field investigation division, said that while the agency was concerned about what the investigators observed at the plant, it was not linking these concerns to the adverse events associated with Baxter's products.

The full Baxter product recall now comprises:

• Heparin sodium injection 1000 units/mL 10mL and 30mL multi-dose vials.


• Heparin sodium injection 5000 units/mL 10mL multi-dose vials.


• Heparin sodium injection 10,000 units/mL 4mL multi-dose vials.


• Heparin sodium injection 1000 USP units/mL single-dose vials.


• Heparin sodium injection 5000 USP units/mL single-dose vials.


• Heparin sodium injection 10,000 USP units/mL single-dose vials.


• All preserved and preservative-free 10 USP units/mL and 100 USP units/mL vials of HEP-LOCK and HEP-LOCK U/P.

The recall excludes Baxter's bagged heparin pre-mix IV solutions of heparin sodium in 5 per cent dextrose injection and heparin sodium in 0.9 per cent sodium chloride injection, said the company.

President of Baxter's Medication Delivery business, Peter J Arduini said:

"We have assurance from the US Food and Drug Administration that there is an adequate supply in the market to meet the demand for these critical and lifesaving drugs."

"The safety and quality of our products is always our highest priority, and we will continue to collaborate with the FDA as we work to determine the cause of the increased rate of adverse reactions and resolve this issue," he added.

Ginseng unproven in U.S.

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LAST year, Health Canada, the Canadian equivalent of the Food and Drug Administration, granted COLD-fX license to make a specific scientific claim -- something the patented American ginseng extract can't do in the U.S. The claim: Two 200-milligram doses of COLD-fX per day "helps reduce the frequency, severity and duration of cold and flu symptoms by boosting the immune system."

The Canadian agency's decision was based on positive findings from a series of well-designed studies. In one, published in the Journal of Alternative and Complementary Medicine in 2006, senior citizens who took COLD-fX for four months were 30% less likely to come down with respiratory symptoms in months three and four than seniors who took a placebo. A 2005 study of adults who took American ginseng or a placebo for four months found that those on the herb had 37% fewer colds; the results were published in the Canadian Medical Assn. Journal. Another large study of seniors, published in the Journal of the American Geriatric Society in 2004, found that the herb resulted in an 89% reduced risk of respiratory symptoms when taken for 12 weeks.

Extract

click to enlarge

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The herb hasn't been tested in children, and its ability to treat symptoms has yet to be tested.

Cold sufferers mindlessly reach for vitamin C

It may not be as beneficial as most Americans think

AMERICANS spend more money on vitamin C, roughly $330 million a year, than on any other purportedly immune-boosting supplement, according to the Nutrition Business Journal. Perhaps because it's been around so long.

"People take vitamin C during cold and flu season because since the 1950s, that's pretty much what we've all been told to do," said Daniel Fabricant, vice president of scientific and regulatory affairs for the Natural Products Assn., a Washington, D.C.-based trade association. "It's just in our subconscious mind-set."

Related Stories
-	Other 'immune boosters'
-	Airborne effects unstudied
-	Contradictory findings on zinc products
-	Elderberry's mixed record
-	Echinacea helps fight a cold -- if it's the right kind
-	Oscillo may help, but not by much
-	Ginseng unproven in U.S.
-	Strong dose of belief helps, too
-	Extra help?

But for just as long, scientists have been going back and forth on whether the vitamin is effective at preventing or treating the common cold.

Vitamin C was first isolated in the 1930s, and studies investigating its potential to prevent colds got underway in the 1940s. In 1970, two-time Nobel Prize-winning chemist Linus Pauling touted the powers of C in his best-selling book, "Vitamin C and the Common Cold." He was particularly inspired by a 1961 study at a ski school in the Alps. Kids in the study who took one gram of vitamin C per day (the U.S. Food and Drug Administration's daily reference value is 60 milligrams a day) had 45% fewer colds than their untreated classmates. They also recovered from colds in two-thirds the time it took their peers to get better.

Pauling's book and subsequent papers on the topic encouraged numerous researchers to investigate the alleged wonder vitamin in large-scale clinical studies of their own. Soon, conflicting evidence began to emerge. Some studies found the vitamin reduced the frequency of colds, some found it reduced the duration of colds, but still others found that it had no effect at all.

Last summer, the Cochrane Collaboration, a nonprofit organization that reviews the science on health topics, reviewed more than 50 well-designed, published studies on vitamin C and the common cold. The researchers found that taking at least 200 milligrams of C on a daily basis doesn't reduce the odds of getting a cold -- but it does speed recovery time by about 8% in adults. In children, it hastens recovery by 13.6%.

The reviewers found another interesting effect. While vitamin C doesn't keep colds at bay in most cases, it cuts the risk of colds in half in people under great physical stress: marathoners, skiers and soldiers training under arctic conditions.

Some evidence also suggests that taking a very large dose of C -- up to 8 grams -- at the onset of a cold could shorten the duration of infection or lessen symptoms, but the Cochrane reviewers concluded that more research was needed to confirm this effect.

For those who aren't winter marathoners or Olympic athletes, vitamin C probably offers little in the way of cold prevention, said Penn State's Dr. Ian Paul. "But is it harmful? Probably not," he added.

High-dose vitamin C does have a slight downside: Three to 5 grams at a time can cause gastrointestinal effects, including diarrhea.

Alzheimer's Disease: Moss Protein Has A Role To Play

Preventing Alzheimer's from developing is a goal of Raphael Kopan, Ph.D., professor of molecular biology and pharmacology at the Washington University School of Medicine. The moss plant (Physcomitrella patens) studied in the laboratory of Ralph S. Quatrano, Ph.D., Spencer T. Olin Professor and chair of the WUSTL biology department on the Danforth Campus, might inch Kopan toward that goal. Here's how.

The gene presenilin in mammals provides the catalytic activity for an enzyme called gamma secretase, which cleaves, or cuts, important proteins Notch, Erb4 and the amyloid precursor protein (APP), all key components of communication channels that cells use to arbitrate functions during development. Two genes occur in mammals in which mutations cause an earlier onset of Alzheimer's. One is APP, where a fragment of the protein accumulates in amyloid plaques, associated with the disease. Another common site for mutations is found in presenilin (PS) proteins. The enzyme gamma secretase contains PS and works to dispose of proteins stuck in the cellular membrane.

This enzyme with PS at its core mediates two cellular decisions. One is to cut APP and as a byproduct, generate the bad peptide associated with Alzheimer's; the other is to cut the Notch protein in response to specific stimuli. Notch is then free to enter the nucleus of cells where it partakes in regulating normal gene expression. Without Notch activity, a mammal has no chance of living.

Notch is a part of short-range mammalian communication channel, and for years it has been known to have a working relationship with PS. However, Notch is absent in plant cells, and presenilin function in plants remained mysterious until Quatrano's post-doctoral researcher, Abha Khandelwal, Ph.D., arrived at Washington University and was interested in understanding signal transduction in plants.

"When I searched the literature, the plant signal transduction pathways were not very well documented as are the mammalian counterparts such as Notch," said Khandelwal. "Meanwhile, my husband Dilip Chandu, Ph.D., was working in the Kopan lab interested in ways to study functions of presenilin without interference from its predominant substrate Notch."

This encouraged Khandelwal to search for the PS gene in the genomes of plants including the recently sequenced moss (Physcomitrella patens) genome, for which the Quatrano lab had access. In addition to the known Arabidopsis presenilin, she found the gene in Physcomitrella and asked, "What is PS doing in moss" Is it acting as an enzyme or does it have a different function" "

Forming a collaboration

"Moss, like yeast, has this great ability where you can actually select a gene and remove it, mutate it, or replace it with another gene from any source. This approach is how we begin to discern a gene's value and function in moss," said Quatrano, who was a world leader in getting the moss genome sequenced. "It is an excellent system to experimentally discern gene function because of this property as well as others that we and a worldwide consortium have developed over the last several years. "

Thus, collaboration was born. By engaging the expertise of the team in the Kopan lab, the Quatrano lab proceeded to start experimenting with PS in moss, which finally resulted in a fruitful combined project, the results of which was recently reported in the Proceedings of the National Academy of Science. Khandelwal proceeded to remove presenilin, and the result was an obvious change- a phenotype. Moss lacking presenilin looked different, growing with straight, rigid filaments instead of curved and bent filaments like the parent moss with the presenilin gene intact.

"That showed the gene has an obvious function that obviously, did not require Notch. We just don't know exactly what it is yet, but we have proposed a hypothesis to be tested," Quatrano said.

The phenotype piqued Kopan's interest: He saw the potential of looking at the role of presenilin independent of Notch. Khandelwal and Chandu took the phenotype, switched out a mammalian form of presenilin into the phenotype, and rescued it. Similarly, inserting the moss gene in mammalian cells resulted in reversing some of the losses experienced by animal cells lacking presenilin function, testifying that the human and moss proteins had an evolutionary conserved function.

"In the moss, they were very nearly interchangeable," Quatrano said. "This suggested that presenilin has a role outside the Notch pathway and may provide clues in mammalian systems as to its primary role, independent of its substrate in mammalian cells."

"We were amazed to realize that genes from moss and humans were not only structurally conserved but also shared similar functions," Khandelwal said.

Moonlighting protein in mammals

"We spent a lot of time trying to find an activity of PS to circumvent cleavage of APP, which has been very difficult, "Kopan said. "Importantly, the human protein acted in plant cells even if its enzymatic activity was removed by mutation. We stumbled upon an observation that presenilin proteins in mammals can perform other functions besides the enzymatic ones, that is, outside its role as gamma secretase. We're now looking closely to define this moonlighting functions and determine their contribution to disease."

In moss, the mutant phenotypes suggest presenilin might play a role in signal gathering, cytoskeleton organization and/or cell wall composition and organization. Quatrano and Khandelwal are checking that out. Kopan, Chandu and others are searching for presenilin's moonlighting activities in mammalian cells.

"As a developmental biologist, my job is to translate the genetic code as if it were a manufacturer's manual, and that is accomplished by gaining detailed understanding of genes and protein function," Kopan said. "Unfortunately, we're doing it one gene at a time, slowly building networks, figuring out what the context is. We can't think of all of it at once. We have to look at a small subset of genes and how they work with their friends, and hope that our observations will fit together in one coherent network."

Quatrano said the collaboration between the two labs is a reflection of what the Genomic Age can do.

"Today, sitting at your computer, you can data mine genomes from hundreds of microorganisms, animals, fungi, insects and plants, and you're seeing more evidence of genes being conserved in widely different organisms," Quatrano said. "This collaboration is a perfect example of bringing two labs together that on the surface have nothing in common other than one protein and two people who were aware of the interests of the other. It's led to a significant contribution that hopefully will lead to further clues as to the function of presenilin."

With this study, the Kopan and Quatrano labs and others could use this outstanding plant model not only to understand some of the off target affects during Alzheimer's Disease therapy, but to unravel novel interactions and pathways in plants.

Stroke Recovery Improves With Music Listening

A new study by researchers in Finland found that listening to music soon after a stroke appeared to improve patients' recovery.

The study is the work of Dr Teppo Sarkamo, a psychologist at the Cognitive Brain Research Unit, Department of Psychology, at the University of Helsinki and at the Helsinki Brain Research Centre, and colleagues, and is to be published today, Wednesday 20th February, in the journal Brain.

Sarkamo and colleagues found stroke patients had a more positive mood and improved recovery of verbal memory and attention focus if they listened to music for about two hours a day, compared to counterparts who listened to audio books or nothing at all.

The researchers said this was the first time such an effect had been observed in humans and has important implications for clinical practice. As Sarkamo explained:

"As a result of our findings, we suggest that everyday music listening during early stroke recovery offers a valuable addition to the patients' care, especially if other active forms of rehabilitation are not yet feasible at this stage, by providing an individually targeted, easy-to-conduct and inexpensive means to facilitate cognitive and emotional recovery."

The researchers carried out a single-blind, randomized controlled trial with 60 patients who had experienced a stroke in the middle cerebral artery (MCA) of the left or right hemisphere of the brain. The trial lasted from March 2004 to May 2006, and the patients were enlisted as soon after they were admitted to hospital as possible. 54 of the patients completed the trial.

Sarkamo explained that it was important for the patients to start the trial as early as possible in the acute post-stroke stage, because:

"The brain can undergo dramatic changes during the first weeks and months of recovery and we know these changes can be enhanced by stimulation from the environment."

For most patients, their stroke had left them experiencing problems with movement and cognitive problems, for instance with memory and attention.

The researchers randomly assigned the patients to one of three groups: a music group, a language group, and a control group.

For two months the patients in the music and language groups listened every day either to music or audio books. The music listeners chose their own music to listen to, including pop, jazz, folk and classical. The control group were given no listening materials.

All three groups also underwent the standard stroke rehabilitation programmes, and the researchers monitored and assessed their progress for up to six months after their stroke.

The results showed that:

• Comparing their ability in the first week after the stroke with three months later, verbal memory in the music listeners improved by 60 per cent.


• This contrasted with 18 per cent in the audio book listeners (language group) and 29 per cent in the non-listeners (control group).


• Focused attention tests showed 17 per cent improvement in the music group and no improvement in the other two groups.


• These differences remained essentially the same after six months.


• The music group experienced less depressed and confused mood than the patients in the control group.

Focused attention tests examined patients' ability to control and perform mental tasks and resolve conflicts among responses.

Commenting on their findings, Sarkamo said:

"The differences in cognitive recovery can be directly attributed to the effect of listening to music."

"Furthermore, the fact that most of the music (63 percent) also contained lyrics would suggest that it is the musical component (or the combination of music and voice) that plays a crucial role in the patients' improved recovery," he added.

The researchers were keen to point out that these are novel findings in a single small study. They show promise, but need to be confirmed by further studies, and especially if we are to understand the underlying mechanisms of the brain.

They also emphasized that since their study examined group effects, it does not mean it will have the same result in individual cases, and patients should not read into this that music will be the only thing that will help them recover from a stroke. They should consider this only as one optional addition to a range of active rehabilitative treatments, for instance speech therapy and neuropsychological rehabilitation.

However, speculating on their findings, the researchers suggested three neural processes as potential explanations for how music might help people recover from strokes:

-- Enhancing arousal and alertness, attention, and mood, by stimulating the dopaminergic mesocorticolimbic system. This system is involved in the processing of pleasure, reward, arousal, motivation and memory.

-- Directly stimulating damaged areas of the brain to promote recovery.

-- Stimulating other processes that help the brain mend itself after neural networks have been damaged (plasticity).

The researchers mentioned that previous studies had shown that after a stroke, in the first few weeks of recovery, patients tend to spend about 75 per cent of their time in their rooms, inactive and unstimulated, without interaction. This period is crucial for maximising brain plasticity and an ideal window of opportunity for rehabilitation.

"Our research shows for the first time that listening to music during this crucial period can enhance cognitive recovery and prevent negative mood, and it has the advantage that it is cheap and easy to organise", concluded Sarkamo.

Caffeine Risks May Rattle Diabetic People

Study Shows Caffeine Elevates Blood Glucose Levels in People With Diabetes

-- There's something about coffee that fights type 2 diabetes -- but it isn't caffeine.

Caffeine makes it hard for people with diabetes to control their blood sugar, new studies suggest.

In the latest of these studies, Duke University researcher James D. Lane, PhD, and colleagues put continuous blood-sugar monitors on 10 people with type 2 diabetes. All were regular coffee drinkers averaging four cups a day, but they stopped drinking coffee during the experiment.

On one day, each patient took a 250 mg caffeine capsule at breakfast and another 250 mg caffeine capsule at lunch. That's roughly the same as having them drink two cups of coffee at each meal. On another day, the same people got placebo pills with no caffeine in them.

The result: On the days the patients took caffeine, their blood-sugar levels were 8% higher. And after every meal -- including dinner -- their blood sugar spiked higher than it did on the day they had no caffeine.

"These are clinically significant blood-sugar elevations due to caffeine," Lane tells WebMD. "Caffeine increases blood glucose by as much as oral diabetes medications decrease it ... It seems the detrimental effects of caffeine are as bad as the beneficial effects of oral diabetes drugs are good."

Lane warns against reading too much into this small, 10-patient study. But he says it does show that caffeine has real effects on the everyday lives of people with diabetes.

"For people with diabetes, drinking coffee or consuming caffeine in other beverages may make it harder for them to control their glucose," he says.

Diabetes, Coffee, and Caffeine

Several studies have found that coffee drinkers -- especially those who drink a lot of coffee -- have a lower risk of diabetes than do other people. So how can coffee both protect against diabetes and worsen diabetes?

WebMD took this question to Harvard researcher Rob van Dam, PhD, who recently analyzed all of these studies.

"In 2002, we thought this did not make any sense," van Dam says. "This is quite a consistent observation, that coffee has a positive effect on diabetes. But it is becoming increasingly clear it is not the caffeine that is beneficial. The picture is now evolving where we see that some other components of coffee besides caffeine may be beneficial in long-term in reduction of diabetes risk."

In fact, van Dam says, it appears that decaf coffee may actually help people keep their blood sugar under control, whereas regular coffee has a detrimental effect on blood sugar. Caffeine unbalanced by other coffee compounds, he says, may be even worse.

Lane says that if there are anti-diabetes compounds in coffee, they don't offset the harmful effects of caffeine.

"We did do one study where we put caffeine in decaf coffee, and still we saw the same exaggeration of glucose after meals in people with diabetes," he says. "So it seems those other compounds in coffee certainly don't eliminate the caffeine effect we have seen."

So what should people do if they have diabetes or are at high risk of diabetes?

"We take a more nuanced posture -- not that coffee is good for you or bad for you, but that maybe it's better to switch to decaf coffee if you have diabetes or the metabolic syndrome," van Dam says.

Lane says people with diabetes are likely to get different effects from coffee.

"I am not going to say that everyone with diabetes has to quit drinking coffee, but I think those who are concerned about their blood sugar not being as low as they'd like it to be should try quitting coffee," he says. "They will be able to tell right away if it improves their glucose control. And it may help reduce their risk of complications of diabetes or reduce their need for additional diabetes medications."

For regular coffee drinkers, Lane says, quitting caffeine may mean three or four days of headache, sleepiness, or mental grogginess. But it does not mean interminable morning misery.

"Every morning we wake up in withdrawal, thinking we need coffee to wake us up -- but it really is just helping us get rid of withdrawal symptoms from not drinking coffee overnight," he says. "Once we get off, well, I wake up feeling better than I did when I was drinking coffee. I don't feel groggy or tired. Everyone I talk to has had a similar experience -- it is not that we become zombies after quitting drinking coffee."

Lane and colleagues report their findings in the February issue of Diabetes Care.