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A wacky study in some ways, but the results give another great reason to eat dark chocolate ("It's for my vision") if the results hold up with more research. Unfortunately the milk chocolate used did not have the same beneficial effects for vision (it just had no effect). But still to be determined is how long does the small increase in vision acuity and contrast sensitivity last after eating dark chocolate, and does it really mean anything in the real world? The beneficial results in vision were found about 2 hours after eating the dark chocolate, so it is unknown how long the beneficial effect lasted.

The good news is that in the study 30 healthy adults were randomly assigned to different groups, it was "double blind" (no one knew who got what to eliminate bias), it was rigorously done, they used real chocolate available to everyone (72% Cacao Dark Chocolate bar vs Crispy Rice Milk Chocolate bar - both from Trader Joe's), and the researchers had no ties to industry. The researchers concluded eating a "dark chocolate bar improves the ability to see low- and high-contrast targets, possibly owing to increased blood flow", but they don't know what this means for real life.

As the researchers point out -  there were 8 times more flavanols in the dark (316.3 mg) vs milk chocolate bar (40 mg). Their thinking was clear in the study's introduction: "Several studies suggest that dark chocolate from favanol-rich cacao beans may enhance blood flow to central and peripheral nervous systems, improve cardiovascular function, and retard memory loss and other signs and symptoms of degenerative diseases, including Alzheimer and Parkinson diseases. The cacao flavanols in dark chocolate have antioxidant effects that retard and partially reverse degenerative changes in various diseases. Dark chocolate consumption also has been associated with enhanced mood and cognition."  Wow.

The big question: How much dark chocolate did they eat to get these beneficial effects?  Answer: 47 grams (or 1 serving, 280 calories) of the 72% cacao dark chocolate. From Medical Xpress:

A bit of dark chocolate might sweeten your vision

It may not replace prescription glasses, but a few bites of dark chocolate might offer a slight and temporary bump up in vision quality, new research suggests. Heart-healthy compounds in chocolate called flavanols appeared to sharpen eyesight for a group of 30 healthy young adults in the new study. The observed change in vision was small, but significant. However, the study authors stressed that it's too early for ophthalmologists to recommend chocolate as medicine for the eyes. 

...continue reading "Eating Dark Chocolate Benefits Vision?"

Image result for dark chocolate Great news for chocolate lovers! A review of 19 good studies (studies with people randomly assigned to different conditions) found that chocolate (whether from cocoa products, chocolate, or cocoa beverages), overall had beneficial effects on cardiometabolic health, and that it may improve lipid metabolism, and reduce inflammation and insulin resistance. This held for both men and women. The main assumption is that it is the flavanols in chocolate that has the beneficial effects on health. From Medical Xpress:

Cocoa compound linked to some cardiovascular biomarker improvements

To the tantalizing delight of chocolate lovers everywhere, a number of recent studies employing various methods have suggested that compounds in cocoa called flavanols could benefit cardiovascular health. Now a systematic review and meta-analysis of 19 randomized controlled trials (RCTs) of cocoa consumption reveals some further pieces of supporting evidence..... "We found that cocoa flavanol intake may reduce dyslipidemia (elevated triglycerides), insulin resistance and systemic inflammation, which are all major subclinical risk factors for cardiometabolic diseases."

Liu noted some limitations in the trials. All studies were small and of short duration, not all of the biomarkers tracked in these studies changed for the better, and none of the studies were designed to test directly whether cocoa flavanol consumption leads to reduced cases of heart attacks or type 2 diabetes. But taking into account some of these heterogeneities across studies, the team's meta-analysis summarizing data from 19 trials found potential beneficial effects of flavanol-rich cocoa on cardiometabolic health. There were small-to-modest but statistically significant improvements among those who ate flavanol-rich cocoa product vs. those who did not.

The greatest effects were seen among trial volunteers who ate between 200 and 600 milligrams of flavanols a day (based on their cocoa consumption). They saw significant declines in blood glucose and insulin, as well as another indicator of insulin resistance called HOMA-IR. They also saw an increase in HDL, or "good," cholesterol. Those consuming higher doses saw some of the insulin resistance benefits and a drop in triglycerides, but not a significant increase in HDL. Those with lower doses of flavanols only saw a significant HDL benefit. 

In general, Lin said, where there were benefits they were evident for both women and men and didn't depend on what physical form the flavanol-rich cocoa product was consumed in —dark chocolate vs. a beverage, for example.

Image result for dark chocolate Two new studies finding benefits from chocolate consumption: dark chocolate boosting athletic performance (in cycling), and long-term chocolate consumption (several times a week for many years) linked to better cognitive function. From Medical Xpress:

Eating chocolate improves cognitive function, study finds

People who ate chocolate at least once a week performed better on multiple cognitive tasks, compared to those who ate chocolate less frequently, according to a new study by researchers at the University of Maine, University of South Australia and Luxembourg Institute of Health that has garnered international attention. 

With age, education, gender, age and race controlled, cognitive tasks were related to following domains, each measured by multiple tests: Visual-Spatial Memory and Organization, Working Memory, Abstract Verbal Reasoning, Scanning and Tracking, and overall cognitive functioning. The 968 participants ages 23–98 in the study came from the Maine-Syracuse Longitudinal Study, directed by Elias, which has tracked more than 1,000 people over 35 years.

The researchers hypothesized that regular intake of cocoa flavanols may be one of several mechanism explaining the cognitive benefits of chocolate. In addition, compared to those who never or rarely ate chocolate, those who ate chocolate weekly had higher total and LDL cholesterol, but lower glucose levels. Hypertension and Type 2 diabetes also were lower in regular chocolate consumers than in nonconsumers. 

From Medical Xpress: Eating dark chocolate as a daily snack could help boost athletic performance, study suggests

Dark chocolate has already been hailed for its positive effects on cardiovascular health – and now a study undertaken at London's Kingston University has found the tasty treat could help give sports enthusiasts an extra edge in their fitness training. A team led by postgraduate research student Rishikesh Kankesh Patel discovered that dark chocolate provides similar benefits to beetroot juice, now taken regularly by elite athletes after studies showed it can improve performance. "Beetroot juice is rich in nitrates, which are converted to nitric oxide in the body. This dilates blood vessels and reduces oxygen consumption – allowing athletes to go further for longer," Mr Patel explained.

The Kingston University team wanted to find out whether dark chocolate could provide a similar boost, as it contains a substance called epicatechin – a type of flavanol found in the cacao bean, that also increases nitric oxide production in the body.

To test the theory, Mr Patel carried out a study with a group of nine amateur cyclists.....After undergoing initial fitness tests to establish a baseline for comparison, the participants were then split into two groups. The first group was asked to replace one of its normal daily snacks with 40 g of a dark chocolate known to be rich in flavanols for a fortnight, while the other participants substituted 40 g of white chocolate for one of their daily snacks as a control.

The effects of the athletes' daily chocolate consumption were then measured in a series of cycling exercise tests in the sports performance laboratory at the University's Penrhyn Road campus....The study, which has now been published in the Journal of the International Society of Sports Nutrition, found that after eating dark chocolate, the riders used less oxygen when cycling at a moderate pace and also covered more distance in a two-minute flat-out time trial.

Image result for dark chocolate So far all the studies I've seen in the past 2 years about cocoa and chocolate have found various beneficial health effects from regularly eating small amounts of cocoa and chocolate. Now 2 new studies found benefits from the flavanols found in cocoa beans and chocolate. The studies found that consuming cocoa flavanols lowers blood pressure, increases flow-mediated vasodilation,improves blood cholesterol profile, and that regular dietary intake may reduce the risk of cardiovascular disease (CVD). However, note that chocolate and cocoa contain other compounds besides flavanols and these may also be exerting positive effects.

So now the question becomes, which chocolates have high levels of flavanols? Modern processing removes some of the flavanols - in fact, the more it undergoes processing, the more flavanols are lost. But it appears that dark chocolate and cocoa that has not undergone Dutch processing is best. According to a Medscape article on cocoa flavanols: "Traditional processing methods that yield "modern chocolate," especially alkalinization (dutching or Dutch processing, to mellow flavor), strips flavanols from cocoa. The bitterness from cacao mostly comes from flavanols. With the emerging recognition of the beneficial effects of flavanols there has been a shift in commercial production towards chocolate forms with high flavanol content." A recent study by Consumer Lab, which compared flavanol levels across many cocoa and chocolate products, also found that some chocolate brands were contaminated with cadmium (a toxic heavy metal), but that cocoa nibs had significantly lower levels. At any rate, the medical evidence does not support gorging on chocolate, but instead consuming chocolate or cocoa in moderation. From Science Daily:

Cocoa flavanols lower blood pressure and increase blood vessel function in healthy people

Two recently published studies in the journals Age and the British Journal of Nutrition (BJN) demonstrate that consuming cocoa flavanols improves cardiovascular function and lessens the burden on the heart that comes with the aging and stiffening of arteries. The studies also provide novel data to indicate that intake of cocoa flavanols reduces the risk of developing cardiovascular disease (CVD).

As we age, our blood vessels become less flexible and less able to expand to let blood flow and circulate normally, and the risk of hypertension also increases. Arterial stiffness and blood vessel dysfunction are linked with cardiovascular disease -- the number one cause of deaths worldwide....Cocoa flavanols are plant-derived bioactives from the cacao bean. Dietary intake of flavanols has been shown to have a beneficial effect on cardiovascular health but the compounds are often destroyed during normal food processing. Earlier studies have demonstrated that cocoa flavanol intake improves the elasticity of blood vessels and lowers blood pressure....These two studies in Age and BJN are the first to look at the different effects dietary cocoa flavanols can have on the blood vessels of healthy, low-risk individuals with no signs or symptoms of cardiovascular disease.

Cocoa flavanols increase blood vessel flexibility and lower blood pressure - In the study published in Age, two groups of 22 young (<35 years of age) and 20 older (50-80 years of age) healthy men consumed either a flavanol-containing drink, or a flavanol-free control drink, twice a day for two weeks. The researchers then measured the effect of flavanols on hallmarks of cardiovascular aging, such as arterial stiffness (as measured by pulse wave velocity), blood pressure and flow-mediated vasodilation (the extent to which blood vessels dilate in response to nitric oxide). They found that vasodilation was significantly improved in both age groups that consumed flavanols over the course of the study (by 33% in the younger age group and 32% in the older age group over the control intervention). In the older age group, a statistically and clinically significant decrease in systolic blood pressure of 4 mm Hg over control was also seen.

Improving cardiovascular health and lowering the risk of CVD - In the second study, published in BJN, the researchers extended their investigations to a larger group (100) of healthy middle-aged men and women (35-60 years) with low risk of CVD. The participants were randomly and blindly assigned into groups that consumed either a flavanol-containing drink or a flavanol-free control drink, twice a day for four weeks.

"We found that intake of flavanols significantly improves several of the hallmarks of cardiovascular health," says Professor Kelm. In particular, the researchers found that consuming flavanols for four weeks significantly increased flow-mediated vasodilation by 21%. Increased flow-mediated vasodilation is a sign of improved endothelial function and has been shown by some studies to be associated with decreased risk of developing CVD. In addition, taking flavanols decreased blood pressure (systolic by 4.4 mmHg, diastolic by 3.9 mmHg), and improved the blood cholesterol profile by decreasing total cholesterol (by 0.2 mmol/L), decreasing LDL cholesterol (by 0.17 mmol/L), and increasing HDL cholesterol (by 0.1 mmol/L).

The researchers also calculated the Framingham Risk Score -- a widely used model to estimate the 10-year cardiovascular risk of an individual -- and found that flavanol intake reduced the risk of CVD. "Our results indicate that dietary flavanol intake reduces the 10-year risk of being diagnosed with CVD by 22% and the 10-year risk of suffering a heart attack by 31%," says Professor Kelm.

The combined results of these studies demonstrate that flavanols are effective at mitigating age-related changes in blood vessels, and could thereby reduce the risk of CVD in healthy individuals. The application of 10-year Framingham Risk Scores should be interpreted with caution as the duration of the BJN study was weeks not years and the number of participants was around 100, not reaching the scale of the Framingham studies. That being said, Professor Kelm comments that "the reduction seen in risk scores suggests that flavanols may have primary preventive potential for CVD."

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. 

Chocolate lovers are rejoicing! From the NY Times:

To Improve a Memory, Consider Chocolate

Science edged closer on Sunday to showing that an antioxidant in chocolate appears to improve some memory skills that people lose with age. In a small study in the journal Nature Neuroscience, healthy people, ages 50 to 69, who drank a mixture high in antioxidants called cocoa flavanols for three months performed better on a memory test than people who drank a low-flavanol mixture.

On average, the improvement of high-flavanol drinkers meant they performed like people two to three decades younger on the study’s memory task, said Dr. Scott A. Small,a neurologist at Columbia University Medical Center and the study’s senior author. They performed about 25 percent better than the low-flavanol group.

The findings support recent research linking flavanols, especially epicatechin, to improved blood circulation, heart health and memory in mice, snails and humans. But experts said the new study, although involving only 37 participants and partly funded by Mars Inc.,the chocolate company, goes further and was a well-controlled, randomized trial led by experienced researchers.

Besides improvements on the memory test — a pattern recognition test involving the kind of skill used in remembering where you parked the car or recalling the face of someone you just met — researchers found increased function in an area of the brain’s hippocampus called the dentate gyrus, which has been linked to this type of memory.

To consume the high-flavanol group’s daily dose of epicatechin, 138 milligrams, would take eating at least 300 grams of dark chocolate a day — about seven average-sized bars. Or possibly about 100 grams of baking chocolate or unsweetened cocoa powder, but concentrations vary widely depending on the processing. Milk chocolate has most epicatechin processed out of it.

More extensive research is planned. As for why flavanols would help memory, one theory is that they improve brain blood flow; another, favored by Dr. Small, is that they cause dendrites, message-receiving branches of neurons, to grow.

Some good foods to eat for their health benefits. The following articles are from Science Daily:

Almonds reduce the risk of heart disease, research shows

Eating almonds can reduce the risk of heart disease by keeping blood vessels healthy, research has shown. Research found that they significantly increase the amount of antioxidants in the blood stream, reduce blood pressure and improve blood flow. These findings add weight to the theory that Mediterranean diets with lots of nuts have big health benefits... "Our study confirms that almonds are a superfood. Previous studies have shown that they keep your heart healthy, but our research proves that it isn't too late to introduce them into your diet -- adding even a handful (around 50g) every day for a short period can help.

Could grapefruit be good for your kidneys?

A natural product found in grapefruit can prevent kidney cysts from forming, new research indicates. Naringenin, which is also present in other citrus fruits, has been found to successfully block the formation of kidney cysts, an effect that occurs in polycystic kidney disease, by regulating the PKD2 protein responsible for the condition. With few treatments currently available, symptoms include high blood pressure and loss of kidney function, and lead to the need for dialysis.

More evidence that dark chocolate is good for you. From Science Daily:

Polyphenols could yield small benefit for people with PAD

In a small study, people with artery problems in their legs (peripheral artery disease) walked a little longer and farther when they ate dark chocolate -- a food rich in polyphenols.The authors suggest that compounds found in cocoa -- polyphenols -- may reduce oxidative stress and improve blood flow in peripheral arteries....Many other polyphenol-rich foods would offer less added sugar, saturated fats, and calories than dark chocolate, such as cloves, dried peppermint, celery seed, capers, and hazelnuts, to name a few.

The United Nations has proclaimed today as the International Day of Happiness. In that spirit is the following article. From Science Daily:

Precise reason for health benefits of dark chocolate: Thank hungry gut microbes

The health benefits of eating dark chocolate have been extolled for centuries, but the exact reason has remained a mystery -- until now. Researchers have just reported that certain bacteria in the stomach gobble the chocolate and ferment it into anti-inflammatory compounds that are good for the heart.

"We found that there are two kinds of microbes in the gut: the 'good' ones and the 'bad' ones," explained Maria Moore, an undergraduate student and one of the study's researchers.

"The good microbes, such as Bifidobacterium and lactic acid bacteria, feast on chocolate," she said. "When you eat dark chocolate, they grow and ferment it, producing compounds that are anti-inflammatory." The other bacteria in the gut are associated with inflammation and can cause gas, bloating, diarrhea and constipation. These include some Clostridia and some E. coli.

"When these compounds are absorbed by the body, they lessen the inflammation of cardiovascular tissue, reducing the long-term risk of stroke," said John Finley, Ph.D., who led the work. He said that this study is the first to look at the effects of dark chocolate on the various types of bacteria in the stomach. The researchers are with Louisiana State University.

The team tested three cocoa powders using a model digestive tract, composed of a series of modified test tubes, to simulate normal digestion. They then subjected the non-digestible materials to anaerobic fermentation using human fecal bacteria, according to Finley.

He explained that cocoa powder, an ingredient in chocolate, contains several polyphenolic, or antioxidant, compounds such as catechin and epicatechin, and a small amount of dietary fiber. Both components are poorly digested and absorbed, but when they reach the colon, the desirable microbes take over. "In our study we found that the fiber is fermented and the large polyphenolic polymers are metabolized to smaller molecules, which are more easily absorbed. These smaller polymers exhibit anti-inflammatory activity," he said.

Finley also noted that combining the fiber in cocoa with prebiotics is likely to improve a person's overall health and help convert polyphenolics in the stomach into anti-inflammatory compounds. "When you ingest prebiotics, the beneficial gut microbial population increases and outcompetes any undesirable microbes in the gut, like those that cause stomach problems," he added. Prebiotics are carbohydrates found in foods like raw garlic and cooked whole wheat flour that humans can't digest but that good bacteria like to eat. This food for your gut's helpful inhabitants also comes in dietary supplements.

Please note that 70 grams equals 2 1/2 ounces of chocolate. From Science Daily:

Why dark chocolate is good for your heart

It might seem too good to be true, but dark chocolate is good for you and scientists now know why. Dark chocolate helps restore flexibility to arteries while also preventing white blood cells from sticking to the walls of blood vessels. Both arterial stiffness and white blood cell adhesion are known factors that play a significant role in atherosclerosis. What's more, the scientists also found that increasing the flavanol content of dark chocolate did not change this effect. This discovery was published in the March 2014 issue of The FASEB Journal.

"We provide a more complete picture of the impact of chocolate consumption in vascular health and show that increasing flavanol content has no added beneficial effect on vascular health," said Diederik Esser, Ph.D., a researcher involved in the work from the Top Institute Food and Nutrition and Wageningen University, Division of Human Nutrition in Wageningen, The Netherlands. "However, this increased flavanol content clearly affected taste and thereby the motivation to eat these chocolates. So the dark side of chocolate is a healthy one."

To make this discovery, Esser and colleagues analyzed 44 middle-aged overweight men over two periods of four weeks as they consumed 70 grams of chocolate per day. Study participants received either specially produced dark chocolate with high flavanol content or chocolate that was regularly produced. Both chocolates had a similar cocoa mass content. Before and after both intervention periods, researchers performed a variety of measurements that are important indicators of vascular health. During the study, participants were advised to refrain from certain energy dense food products to prevent weight gain. Scientists also evaluated the sensory properties of the high flavanol chocolate and the regular chocolate and collected the motivation scores of the participants to eat these chocolates during the intervention.

"The effect that dark chocolate has on our bodies is encouraging not only because it allows us to indulge with less guilt, but also because it could lead the way to therapies that do the same thing as dark chocolate but with better and more consistent results," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. 

A feel good article. From Science Daily:

Love is good for the heart, cardiologist says

With Valentine's Day just one day away, Vanderbilt Heart and Vascular Institute cardiologist Julie Damp, M.D., says being involved in a healthy, loving relationship is good for the heart.  "There are different theories behind why that might be," Damp said.

A recent study from Finland showed that married men and women had a significantly lower risk of both having heart attacks and dying from a heart attack compared to people who were single.

There is also a theory that people who are in loving relationships may experience neuro-hormonal changes that have positive effects on the body, including the cardiovascular system," she said, explaining that there are certain hormone levels in the body that vary depending on the level of an individual's stress and anxiety.

Giving your loved one a box of dark chocolates and a bottle of red wine won't hurt either. Studies suggest they are good for the heart, as well.

Dark chocolate contains flavonoids, which are antioxidants. Antioxidants have positive effects on many different body systems including the cardiovascular system. The high concentration of cocoa in dark chocolate appears to be what offers the flavonoid benefit.

"Dark chocolate has been shown to be associated with lower blood pressure, lower blood sugar levels and improvement in the way your blood vessels dilate and relax," Damp said.