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A nice summary article about the benefits and risks of coffee consumption. Summary of effects of drinking coffee1) May potentially increase blood pressure, but also may lower the risk for coronary disease, and protect against heart disease. 2) May cut stroke risk by as much as 25%, 3) Linked to  improved glucose metabolism, reduced risk for type 2 diabetes, and promotion of weight loss in overweight patients. 4) May reduce the risk for several cancers. 5) Appears to slow the progression of dementia and Parkinson's disease. 6) A significantly decreased risk of developing depression. 7) Slows progression in alcoholic cirrhosis, hepatitis C, and NAFLD (non-alcoholic fatty liver disease). 8) May be beneficial in dry-eye syndrome, gout, and in preventing MRSA infection. 9) May increase blood pressure, anxiety, insomnia, tremor, withdrawal symptoms, and potential increased risk of glaucoma. From Medscape:

How Healthy Is Coffee? The Latest Evidence

Earlier this year, the Dietary Guidelines Advisory Committee (DGAC) released a report[1] stating that up to five cups of coffee per day, or up to 400 mg of caffeine, is not associated with long-term health risks. Not only that, they highlighted observational evidence that coffee consumption is associated with reduced risk for several diseases, including type 2 diabetes, cardiovascular disease (CVD), and neurodegenerative disorders. The body of data suggesting that moderate coffee—and, in all likelihood, tea—consumption is not only safe but beneficial in a variety of mental and medical conditions is growing fast.

A 2012 study of over 400,000 people, published in the New England Journal of Medicine, reported that coffee consumption is associated with a 10% reduction in all-cause mortality at 13-year follow-up.... It's important to note that much of the evidence on the potential health effects of coffee, caffeine, and other foods and nutrients is associational and doesn't prove causality—observational investigations come with limitations and often rely on error-prone methods such as patient questionnaires. However, the sheer volume of existing observational data linking coffee and/or caffeine with various health benefits—as well as, in many cases, evidence of a dose response—suggests that the most widely consumed stimulant in the world has positive influences on our health. 

Cardiovascular Disease:...However, when caffeine is ingested via coffee, enduring blood pressure elevations are small and cardiovascular risks may be balanced by protective properties. Coffee beans contain antioxidant compounds that reduce oxidation of low-density lipoprotein (LDL) cholesterol, and coffee consumption has been associated with reduced concentrations of inflammatory markers. Moderate coffee intake is associated with a lower risk for coronary heart disease as far out as 10 years, and data suggest that an average of two cups per day protects against heart failure.

Cerebrovascular Disease and Stroke: The vascular benefits of coffee are not lost on the brain. According to a 2011 meta-analysis, consuming between one and six cups per day reportedly cut stroke risk by 17%. A 22%-25% risk reduction was seen in a large sample of Swedish women followed for an average of 10 years.

Diabetes:...Numerous studies have linked regular coffee drinking with improved glucose metabolism, insulin secretion, and a significantly reduced risk for diabetes. Most recently, findings from a long-term study published this year suggest that coffee drinkers are roughly half as likely to develop type 2 diabetes as are nonconsumers, even after accounting for smoking, high blood pressure, and family history of diabetes.

Cancer: ...Evidence suggests that moderate to heavy coffee consumption can reduce the risk for numerous cancers, including endometrial (> 4 cups/day), prostate (6 cups/day), head and neck (4 cups/day), basal cell carcinoma (> 3 cups/day), melanoma,and breast cancer (> 5 cups/day). The benefits are thought to be at least partially due to coffee's antioxidant and antimutagenic properties.

Neurodegeneration: Beyond the short-term mental boost it provides, coffee also appears to benefit longer-term cognitive well-being. A 2012 study reported that patients with mild cognitive impairment and plasma caffeine levels of > 1200 ng/mL—courtesy of approximately three to five cups of coffee per day—avoided progression to dementia over the following 2-4 years. On a related note, a study from last year reported that caffeine consumption appears to enhance memory consolidation....Caffeinated coffee has long been thought to be neuroprotective in Parkinson disease (PD)....—as well as in multiple sclerosis

Depression: A 2011 study suggests that a boost in coffee consumption might also benefit our mental health: Women who drank two to three cups of coffee per day had a 15% decreased risk for depression compared with those who drank less than one cup per week. A 20% decreased risk was seen in those who drank four cups or more per day. Newer work also suggests that regular coffee drinking may be protective against depression.

Liver Disease: The liver might help break down coffee, but coffee might protect the liver (in some cases). Evidence suggests that coffee consumption slows disease progression in patients with alcoholic cirrhosis and hepatitis C, and reduces the risk of developing hepatocellular carcinoma. A 2012 study reported that coffee intake is associated with a lower risk for nonalcoholic fatty liver disease (NAFLD), while work published in 2014 found that coffee protects against liver fibrosis in those with already established NAFLD.

And That's Not All…: An assortment of other research suggests that coffee intake might also relieve dry-eye syndrome by increasing tear production, reduce the risk for gout, and potentially fight infection. Coffee and hot tea consumption were found to be protective against one of the medical community's most concerning bugs, methicillin-resistant Staphylococcus aureus (MRSA). While it remains unclear whether the beverages have systemic antimicrobial activity, study participants who reported any consumption of either were approximately half as likely to have MRSA in their nasal passages.

And Finally, the Risks: As is often the case, with benefits come risks, and coffee consumption certainly has negative medical and psychiatric effects to consider. Besides the aforementioned potential increase in blood pressure, coffee can incite or worsen anxiety, insomnia, and tremor and potentially elevate glaucoma risk. Also, given the potential severity of symptoms, caffeine withdrawal syndrome is included as a diagnosis in the DSM-5.

Image result for dark chocolateGreat results (dark chocolate improves attention and lowers blood pressure), but keep in mind that the research was sponsored by the Hershey company. But not to worry, it basically found what other studies have found - that chocolate is a stimulant that activates the brain. From Science Daily:

Eat dark chocolate to beat the midday slump?

Larry Stevens eats a piece of high-cacao content chocolate every afternoon, which is in part because he has developed a taste for the unsweetened dark chocolate. It's also because research shows that it lowers blood pressure and his new study reveals that it improves attention, which is especially important when hitting that midday slump.

"Chocolate is indeed a stimulant and it activates the brain in a really special way," said Stevens, a professor of psychological sciences at NAU. "It can increase brain characteristics of attention, and it also significantly affects blood pressure levels."

Historically, chocolate has been recognized as a vasodilator, meaning that it widens blood vessels and lowers blood pressure in the long run, but chocolate also contains some powerful stimulants. Stevens said his team wanted to investigate if people who consume chocolate would see an immediate stimulant effect.

Stevens and his colleagues in the Department of Psychological Sciences performed the EEG study with 122 participants between the ages of 18 and 25 years old. The researchers examined the EEG levels and blood pressure effects of consuming a 60 percent cacao confection compared with five control conditions...The results for the participants who consumed the 60 percent cacao chocolate showed that the brain was more alert and attentive after consumption. Their blood pressure also increased for a short time.

The most interesting results came from one of the control conditions, a 60 percent cacao chocolate which included L-theanine, an amino acid found in green tea that acts as a relaxant. This combination hasn't been introduced to the market yet, so you won't find it on the candy aisle...."L-theanine is a really fascinating product that lowers blood pressure and produces what we call alpha waves in the brain that are very calm and peaceful," Stevens said. For participants who consumed the high-cacao content chocolate with L-theanine, researchers recorded an immediate drop in blood pressure. 

The statements in this editorial may be obvious to many, but it is nicely written and needs to be said. Basically it says that exercise will not help you overcome the ill effects of a poor diet. I agree with what was said, but felt that what was missing was mention that a poor diet also has negative effects on the microbiome (the community of microbes living within the person) - which we know is linked to health problems. From Medscape:

Workouts Do Not Work Off Ill Effects of Poor Die

Exercise enthusiasts cannot work off the ill effects of an unhealthy diet, say the authors of an editorial published online April 22 in the British Journal of Sports Medicine. "Let us bust the myth of physical inactivity and obesity," the authors write. "You cannot outrun a bad diet."

Physical activity levels in Western nations have remained flat during the past 3 decades, even as obesity rates have exploded. That observation is just one sign that calories, not lack of exercise, are driving the obesity crisis, argue Aseem Malhotra, MD, honorary consultant cardiologist at Frimley Park Hospital, United Kingdom, and science director for Action on Sugar, United Kingdom, and colleagues.

"However, the obesity epidemic represents only the tip of a much larger iceberg of the adverse health consequences of poor diet," the authors write. They say that the Lancet global burden of disease reports concluded that poor diet contributes to more disease than a combination of inadequate physical activity, alcohol, and smoking. As many as 40% of people with normal body weight will suffer from metabolic abnormalities typically associated with obesity, the authors write, including hypertension, dyslipidemia, nonalcoholic fatty liver disease, and cardiovascular disease.

Dr Malhotra and colleagues blame food industry marketing for promoting exercise over diet, comparing food industry public relations with discredited tactics used by the tobacco industry in the past. They say Coca Cola "pushes the message that 'all calories count'; they associate their products with sport, suggesting it is ok to consume their drinks as long as you exercise. However science tells us this is misleading and wrong."

The kind of calorie matters too, they emphasize. Calories from sugar promote fat storage and hunger; fat calories induce satiety. For every 150 calories consumed from sugar, there is an 11-fold increase in the prevalence of type 2 diabetes independent of weight or physical activity levels compared with consumption of 150 calories of fat or protein.

This is the latest study raising health concerns about energy drinks, which include popular brands Red Bull and Monster. (See review article Energy Beverages: Content and Safety and from Time What’s In Your Energy Drink? ). And remember, they are not a "real food" when you look at the ingredients (e.g., caffeine, taurine and glucuronolactone, artificial flavors, artificial sweeteners, colors). From Live Science:

Energy Drinks Raise Blood Pressure, Study Finds

Energy drinks might give you some pep — but they might also be priming you for heart problems, a new study finds. Researchers found that energy drinks can raise blood pressure to potentially unhealthy levels. The effect was far more prominent in young adults who did not consume caffeine regularly, according to the study, presented March 14 at an American College of Cardiology meeting in San Diego.

In this study, the research team — led by Dr. Anna Svatikova, a cardiovascular-diseases fellow at the Mayo Clinic in Rochester, Minnesota — gave a can of a commercially available energy drink to 25 healthy volunteers, whose ages ranged from 19 to 40. On a different day, the participants drank the same amount of a placebo drink. The researchers measured the participants' heart rate and blood pressure before and after the drinks.

The participants experienced a more marked rise in blood pressure after consuming the energy drink than after drinking the placebo, according to the findings. The participants' average systolic blood pressure (the top number in a blood pressure reading) increased by 3 percent more after they drank an energy drink, compared with after they drank the placebo drink. [5 Health Problems Linked to Energy Drinks]

The effect was most dramatic in people who did not typically consume more than a small cup of coffee or other caffeinated drink daily. In this so-called "caffeine-naive" group, the blood pressure increase was twice as high as the increase seen in the people who drank at least the equivalent of a cup of coffee on a daily basis, the researchers said in a statement...Scientists do not know whether it is the caffeine, taurine or other ingredients found in energy drinks — or a combination of ingredients — that can adversely affect the heart.

In a separate study, presented last year at an American Heart Association meeting by Maj. Emily Fletcher of the David Grant Air Force Medical Center, healthy volunteers experienced a greater increase in blood pressure after they consumed an energy drink compared to after they drank a coffee drink that had an equal amount of caffeine. This result, Fletcher said, suggests that ingredients in the energy drink other than caffeine were conspiring to raise blood pressure.

Excellent for those who want to exercise more, but don't want something complex. This is so simple that there is NO excuse for not doing this: walk fast for 3 minutes, then 3 minutes of strolling, and repeat 5 times (total=30 minutes). From NY Times:

Walk Hard. Walk Easy. Repeat.

Intense, interval-style workouts — brief bouts of very hard exercise broken up by periods of recovery — have been shown to improve the health and fitness of people who exert themselves for only a few minutes a week. Such efficiency is alluring, and has helped this kind of conditioning attract widespread media attention in recent years (including in this column). But high-intensity interval training programs aren’t for everyone....That doubt is what makes some news out of Japan about a much-less-punishing form of interval training so welcome.

A decade ago, scientists led by Dr. Hiroshi Nose at the Shinshu University Graduate School of Medicine in Matsumoto, Japan, started developing walking programs. They knew that walking was physically the easiest (and also the most practical) exercise for those in middle age and older, but the researchers suspected that people might need to push themselves to achieve the greatest health benefits. So they created a regimen consisting of three minutes of fast walking at a pace that Nose says approximates a 6 or 7 on a scale of exertion from 1 to 10. Each “somewhat-hard” three-minute spell was followed by three minutes of gentle strolling.

In their original experiment, the results of which were published in 2007, walkers between the ages of 44 and 78 completed five sets of intervals, for a total of 30 minutes of walking at least three times a week. A separate group of older volunteers walked at a continuous, moderate pace, equivalent to about a 4 on the same exertion scale. After five months, the fitness and health of the older, moderate group had barely improved. The interval walkers, however, significantly improved aerobic fitness, leg strength and blood-pressure readings.

In their latest study, which came out in December in the Journal of Applied Physiology, Nose and his colleagues report that most of the participants stayed with the walking program long after their original five-month commitment ended. Two years later, almost 70 percent of the walkers with whom the researchers remained in contact were still following their regimen at least three times a week and had retained or improved their health gains. Those who quit often cited “family, health and job issues,” says Dr. Shizue Masuki, the new study’s lead author, but they rarely complained about the complexity or difficulty of the training.

So those who have considered high-intensity interval training but have been apprehensive about its demands should go for a walk. “Perform the training for 10 minutes in the morning, 10 minutes in the afternoon and 10 minutes in the evening,” Masuki suggests. Three days of exercise per week is best, but if that’s too challenging, she says, “do it on the weekend” and cram the workouts into two days. Doing so, Masuki adds, “can have a profound effect on physiological regulation.”

Yes, this finding is important , but what should be also noted is this sentence in the article: "He also noted that it may not be a disease itself, but the treatment for the disease, that's actually responsible for reproductive malfunction." It has been known for decades that men's sperm is affected by environmental chemicals (such as pesticides), alcohol, smoking, and medications. So it's important to figure out if it's the medicine or the health condition that's causing the problem - or perhaps it's both. From Science Daily:

Infertility is a warning: Poor semen quality linked to hypertension, other health problems

A study of men who were evaluated for the cause of their infertility finds previously unknown relationships between deficiencies in their semen and other, seemingly unrelated health problems. A study of more than 9,000 men with fertility problems has revealed a correlation between the number of different defects in a man's semen and the likelihood that the man has other health problems.

The study, conducted by investigators at the Stanford University School of Medicine, also links poor semen quality to a higher chance of having various specific health conditions, such as hypertension, and more generally to skin and endocrine disorders....A study Eisenberg co-authored a few years ago showed that infertile men had higher rates of overall mortality, as well as mortality linked to heart problems, in the years following an infertility evaluation. 

In the new study, Eisenberg and his colleagues analyzed the medical records of 9,387 men, mostly between 30 and 50 years old, who had been evaluated at Stanford Hospital & Clinics (now Stanford Health Care) between 1994 and 2011 to determine the cause of their infertility. ...So, using the database, the investigators were able to compare the overall health status of men who had semen defects to that of the men who didn't.

With a median age of 38, this was a fairly young group of men. However, 44 percent of all the men had some additional health problem besides the fertility problem that brought them to the clinic. In particular, the investigators found a substantial link between poor semen quality and specific diseases of the circulatory system, notably hypertension, vascular disease and heart disease. 

In addition, as the number of different kinds of defects in a man's semen rose, so did his likelihood of having a skin disease or endocrine disorder. When looking at the severity of all health problems, the scientists observed a statistically significant connection between the number of different ways in which a man's semen was deficient and the likelihood of his having a substantial health problem.... He also noted that it may not be a disease itself, but the treatment for the disease, that's actually responsible for reproductive malfunction. He said he is exploring this possibility now.

This article mentions a few of the other issues that are linked with male infertility.While incomplete, at least it mentions smoking, BPA exposure, binge drinking, obesity, and lack of sleep.From Medical Daily:

Your Sperm And Your Health: What Your Semen Can Tell You About Your Health

The following article focused on other links to male infertility. It also discussed an interesting 2012 study that looked at the effects of wearing tight briefs (which heats the genitals) versus boxers on sperm production (hint: briefs had very negative effect). From Five Thirty Eight Science:

Men, Those Tightie Whities Really Are Killing Your Sperm Count

I bet eating fresh blueberries daily instead of blueberry powder would not only be more delicious, but also have even more health benefits. From Science Daily:

Blueberries may help reduce blood pressure and arterial stiffness

Just one cup of blueberries per day could be the key to reducing blood pressure and arterial stiffness, both of which are associated with cardiovascular disease. .... Johnson said she is interested in looking at how functional foods -- foods that have a positive impact on health beyond basic nutrition -- can prevent and reverse negative health outcomes, particularly for postmenopausal women.

Over an eight-week period, 48 postmenopausal women with pre- and stage-1 hypertension were randomly assigned to receive either 22 grams of freeze-dried blueberry powder -- the equivalent to one cup of fresh blueberries -- or 22 grams of a placebo powder. Participants, meanwhile, continued their normal diet and exercise routines.

At the end of the eight weeks, participants receiving the blueberry powder on average had a 7 mmHg (5.1 percent) decrease in systolic blood pressure, which is the top number in the blood pressure reading that measures the pressure in the arteries when the heart beats. They also saw a 5 mmHg (6.3 percent) reduction in diastolic blood pressure, or the bottom number measuring the pressure in the arteries between heartbeats.

Additionally, participants in the blueberry-treated group had an average reduction of 97 cm/second (6.5 percent) in arterial stiffness.They also found that nitric oxide, a blood biomarker known to be involved in the widening of blood vessels, increased by 68.5 percent. That is important, Johnson said, because arterial stiffness and the narrowing of blood vessels are both a part of hypertension. This rise in nitric oxide helps explain the reductions in blood pressure.

The bottom line: for better health be physically active at least is 2.5 hours of week. Note that HbA1c is a measure of glycated hemoglobin which identifies average plasma glucose concentration (and lower is better). From Medscape:

Exercise Tied to Cardiometabolic Markers in Clinic Patients 

Healthy, middle-aged outpatients who were physically active for at least 2.5 hours a week had better blood pressure and blood glucose levels than their sedentary peers in a large cross-sectional study in California. The differences were especially notable in women, in this study published online December 18, 2014 in Preventing Chronic Disease.

Men and women who were consistently physically active—defined as performing moderate to vigorous activity such as brisk walking for at least 150 minutes a week, as self-reported at all three outpatient visits in a 33-month period—had lower diastolic blood pressure, glucose, and HbA1c levels than patients not reporting exercise at that level.

Moreover, on a population level, the observed associations "were comparable to those needed to reduce the risk of coronary heart disease, stroke, and diabetes," they continue. "If healthcare providers would routinely assess the physical activity of their patients and refer those who are physically inactive to effective physical-activity programs, it may reduce the burden of future chronic diseases."

They analyzed electronic records from over 622,000 adults covered by Kaiser Permanente Southern California healthcare insurance who made at least three clinic visits between April 2010 and December 2012 and were not being treated for diabetes or hypertension.

The consistently active women had systolic and diastolic blood pressures that were 4.60-mm-Hg lower and 3.28-mm-Hg lower, respectively, than inactive women. Perhaps surprisingly, somewhat active women had slightly better blood-pressure values than the more active group.

Further reasons to try to consume foods and beverages from glass containers and avoid cans and plastic bottles. Note that the BPA caused changes within 2 hours, and that BPA-free alternatives may be no better than BPA. Some researchers are speculating whether the high incidence of hypertension is linked to the prevalence of BPA in our environment. From Medical Xpress:

Cans lined with Bisphenol A may increase blood pressure

Drinking or eating from cans or bottles lined with Bisphenol A (BPA) could raise your blood pressure, according to new research reported in the American Heart Association's journal Hypertension. BPA, a chemical used as an epoxy lining for cans and plastic bottles, is everywhere, and its consumption has been associated with high blood pressure and heart rate variability. Previous studies have shown that BPA can leach into foods and drinks.

"A 5 mm Hg increase in systolic blood pressure by drinking two canned beverages may cause clinically significant problems, particularly in patients with heart disease or hypertension," said Yun-Chul Hong, M.D., Ph.D., study author... "A 20 mm Hg increase in systolic blood pressure doubles the risk of cardiovascular disease."

In this study, researchers conducted a randomized crossover trial recruiting 60 adults, mostly Korean women, over the age of 60 from a local community center. Each trial member visited the study site three times and was randomly provided with soy milk in either glass bottles or cans. Later urine was collected and tested for BPA concentration, blood pressure and heart rate variability two hours after consumption of each beverage.

Urinary BPA concentration increased by up to 1,600 percent after consuming canned beverages compared to after consuming the glass-bottled beverages.. Soy milk was the ideal beverage for the test because it has no known ingredient that elevates blood pressure, researchers said.

UPDATE: The NY Times has a nice write-up of this research with further details:

BPA in Cans and Plastic Bottles Linked to Quick Rise in Blood Pressure

A single instance of increased blood pressure may not be particularly harmful. But the findings suggest that for people who drink from multiple cans or plastic bottles every day, the repeated exposure over time could contribute to hypertension, said Dr. Karin B. Michels, an expert on BPA who was not involved in the new research.

BPA has been used since the 1960s to make countless everyday products like plastic bottles, food containers, contact lenses, and even sippy cups and baby bottles. The chemical can leach into food, and studies show that the vast majority of Americans who are tested have BPA in their urine.

The chemical is an endocrine disrupter that can mimic estrogen. In 2012, the Food and Drug Administration said BPA could no longer be used in baby bottles and children’s drinking cups. Canadian regulators formally declared BPA a toxic substance in 2010 and banned it from all children’s products.

Because of growing consumer concerns, some bottles and packaged food products now carry “BPA free” claims on their labels. However, these products often contain chemically similar alternatives – like bisphenol S. One study in the journal Environmental Health Perspectives found that plastic products advertised as BPA-free still leached chemicals with estrogenic activity – and some of these chemicals were even more potent than BPA.

Think lifestyle changes, not medications. From Medical Daily:

Mild Hypertension Should Be Treated With Advice On Lifestyle Changes, Not Medication

In 2013, Dr. Iona Heath, a retired general practitioner published an article in the Journal of  the American Medical Association, in which she spoke about the side effects of overtreatment and overdiagnosis of mild hypertension. Now, in a new study, researchers revisit this idea, saying that unnecessary treatment of mild hypertension in low-risk patients is harming them and putting a burden on health care resources. They also argue that there's a need to reexamine criteria for diagnosing hypertension and treating blood pressure. 

About 40 percent of the world’s population, including 67 million American adults, have hypertension. Over half are classified as having mild hypertension. 

More than half of people with mild hypertension are treated with drugs, but there has been no evidence to suggest that blood pressure-lowering drugs prevent heart attacks. Instead of prescribing drugs to control mild hypertension, the authors urge clinicians to recommend healthier lifestyles to patients, which include exercising, quitting smoking, and decreased alcohol consumption. They also urge clinics to improve the accuracy of blood pressure-measuring instruments and to inform patients about measuring blood pressure at home. 

From Medical Xpress:

Experts raise concern over unnecessary treatment of mild hypertension in low risk people

Lowering the drug threshold for high blood pressure has exposed millions of low-risk people around the world to drug treatment of uncertain benefit at huge cost to health systems, warn US experts in BMJ today. Dr Stephen Martin and colleagues argue that this strategy is failing patients and wasting healthcare resources.

Over half of people with mild hypertension are treated with medication. Yet treating low risk mildly hypertensive patients with drugs has not been proven to reduce cardiovascular disease or death. The authors argue that overemphasis on drug treatment "risks adverse effects, such as increased risk of falls, and misses opportunities to modify individual lifestyle choices and tackle lifestyle factors at a public health level."

And for those over 65 the levels can be even higher. From Science News:

'Mild' control of systolic blood pressure in older adults is adequate: 150 is good enough

A broad review of the use of medications to reduce blood pressure has confirmed that "mild" control of systolic pressure is adequate for adults age 65 or older -- in the elderly, there's no clear benefit to more aggressive use of medications to achieve a lower pressure. Historically, most medical practitioners tried to achieve control of systolic pressure -- the higher of the two blood pressure readings -- to 140 or less. Recently changed guidelines now suggest that for adults over 60, keeping the systolic pressure at 150 or less is adequate, and this extensive analysis confirms that.