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For years studies have suggested that eating blueberries and other berries is good for our health (here, here, and here). Now another study suggests that eating wild blueberries benefits children's thinking, specifically attention and "executive function" (mental processes which lets people plan, organize, and complete tasks). What was nice in this study was that it was "double-blind"- which meant that biases couldn't influence the results. 

Flavonoids are a diverse group of phytonutrients (plant chemicals) found in almost all fruits and vegetables. They are powerful antioxidants with anti-inflammatory and immune system benefits. And yes, other studies have also found various benefits to mental processes with an increase of flavonoids in the diet - in both children and adults.

What foods contain flavonoids? There are 6 main classes of flavonoids, and each is found in different foods: - Anthocyanidins – found in red, purple,and blue berries, red wine, and red and purple grapes. - Flavonols - found in onions, leeks, broccoli, Brussels sprouts, kale, tea, berries, beans, and apples. - Flavones - found in parsley, celery, and hot peppers. - Isoflavones - found in soybeans, soy products, and legumes. - Flavanones - found in citrus fruit and tomatoes. - Flavanols - found in tea, red wine, grapes, apples, fava beans, and cocoa. From Medical Xpress:

Primary school children could show better attention by consuming flavonoid-rich blueberries, following a study conducted by the University of Reading. In a paper published in Food & Function, a group of 7-10 year olds who consumed a drink containing wild blueberries or a matched placebo and were tested on their speed and accuracy in completing an executive task function on a computer.The double blind trial found that the children who consumed the flavonoid-rich blueberry drink had 9% quicker reaction times on the test without any sacrifice of accuracy. In particular, the effect was more noticeable as the tests got harder.

Previous [Univ. of] Reading research has shown that consuming wild blueberries can improve mood in children and young people, simple memory recall in primary school children, and that other flavonoid rich drinks such as orange juice, can also improve memory and concentration.

Wild blueberries are grown and harvested in North America, and are smaller than regular blueberries, and are higher in flavonoids compared to regular varieties. The double-blind trial used a flavonoid-rich wild blueberry drink, with a matched placebo contained 8.9 g of fructose, 7.99 g of glucose and 4 mg of vitamin C matching the levels of nutrients found in the blueberry drink. [Original study.] 

A new study was published that supports eating lots of blueberries (or drinking blueberry juice) for health - this time better brain functioning in people aged 65 to 77 who drank concentrated blueberry juice daily for 12 weeks. The people randomly assigned to the group drinking blueberry juice daily showed improvements in cognitive function, blood flow to the brain, and activation of the brain while carrying out cognitive tests. The people received MRIs (magnetic resonance imaging), as well as various blood tests and cognitive tests.

And how much did they drink of the juice daily? Thirty ml or 1 ounce of blueberry concentrate (which provided 387 mg anthocyanins) which was diluted with tap water. Anthocyanins are anti-oxidants that belong to a class of compounds called flavonoids, and are found in high concentrations in blueberries, cherries, and plums. The blueberry concentrate amount was equivalent to about 230 grams of blueberries - about 1 1/3 cups blueberries.

What was good about the study was that to eliminate bias people were both randomly assigned to the blueberry juice group or a placebo group (they drank a synthetic fruit cordial) - and it was "double-blind" so that no one knew who was in which group. Interestingly, people who were already eating more than 5 portions of fruits daily were excluded from the study - because so many other studies have already found all sorts of brain benefits from a diet with lots of fruits and berries. But the main conclusion from this and other related research is: eating lots of berries is good for you and has health benefits. From Medical Xpress:

Blueberry concentrate improves brain function in older people

Drinking concentrated blueberry juice improves brain function in older people, according to research by the University of Exeter. In the study, healthy people aged 65-77 who drank concentrated blueberry juice every day showed improvements in cognitive function, blood flow to the brain and activation of the brain while carrying out cognitive tests. There was also evidence suggesting improvement in working memory. Blueberries are rich in flavonoids, which possess antioxidant and anti-inflammatory properties.

Of the 26 healthy adults in the study, 12 were given concentrated blueberry juice - providing the equivalent of 230 g of blueberries - once a day, while 14 received a placebo. Before and after the 12-week period, participants took a range of cognitive tests while an MRI scanner monitored their brain function and resting brain blood flow was measured. Compared to the placebo group, those who took the blueberry supplement showed significant increases in brain activity in brain areas related to the tests. The study excluded anyone who said they consumed more than five portions of fruit and vegetables per day, and all participants were told to stick to their normal diet throughout. [Original study.]

 This study showed an association of eating lots of flavonoid rich foods (strawberries, blueberries, cherries, blackberries, red wine, apples, pears, and citrus products) and lower rates of erectile dysfunction. A higher intake of several flavonoids also reduces diabetes and cardiovascular disease risk. Keep in mind that erectile dysfunction is thought to be of vascular etiology (the cause) and so shares risk factors (such as hypertension, obesity, and smoking) with cardiovascular disease. Studies have shown that lifestyle factors such as plenty of exercise, being of normal weight, and a Mediterranean style diet rich in whole grains, fruit, vegetables, nuts, legumes, and olive oil was associated with both lower rates of erectile dysfunction and an improvement in erectile function in men. So don't focus just on the flavonoids, but on the whole lifestyle package. From Science Daily:

Blueberries, citrus fruits, red wine associated with reduced erectile dysfunction

Flavonoid-rich foods are associated with a reduced risk of erectile dysfunction -- according to a new collaborative study from the University of East Anglia (UEA) and Harvard University. Research published in The American Journal of Clinical Nutrition reveals that eating foods rich in certain flavonoids is associated with a reduced risk of erectile dysfunction in men, with the greatest benefit in those under 70.

Of all the different flavonoids, Anthocyanins (found in blueberries, cherries, blackberries, radishes and blackcurrant), flavanones and flavones (found in citrus fruits) were found to offer the greatest benefits in preventing the condition.

It is already known that increased exercise can improve erectile function, but this research shows that eating a flavonoid-rich diet is as good for erectile function as briskly walking for up to five hours a week. The study also showed that a higher total fruit intake was associated with a 14 per cent reduction in the risk of erectile dysfunction. And that a combination of consuming flavonoid-rich foods with exercise can reduce the risk by 21 per cent.

More than 50,000 middle aged men were included in this large population based study. They were asked about their ability to have and maintain an erection sufficient for intercourse -- dating back to 1986. Data on dietary intake was also collected every four years.....More than one third of the men surveyed reported suffering new onset erectile dysfunction. But those who consumed a diet rich in anthocyanins, flavones and flavanones were less likely to suffer the condition.

Prof Cassidy said: "The top sources of anthocyanins, flavones and flavanones consumed in the US are strawberries, blueberries, red wine, apples, pears, and citrus products.""We also found that the benefits were strongest among younger men," she added. The team also looked at other lifestyle factors and found that men who consumed a high intake of anthocyanins and flavanones and who were also physically active had the lowest risk of erectile dysfunction.

Dr Eric Rimm, senior author on the study and a Professor of Epidemiology and Nutrition at the Harvard TH Chan School of Public Health, said: "As well as improving sexual health for middle-aged men, there is another important benefit linked to heart health. Erectile dysfunction is often an early barometer of poor vascular function and offers a critical opportunity to intervene and prevent cardiovascular disease, heart attack and even death.

 The important thing learned from this study (though it was done in the laboratory and not directly on humans) is that it supports that apigenin (in the same chemical group as flavonoids) is important for neuron formation and for strengthening connections between brain cells. Flavonoids are known to positively affect memory and learning, and to preserve and enhance brain function. Apigenin is found in many fruits and vegetables, but common sources are parsley, celery, celeriac, thyme, chamomile, grapefruit, onions, oranges, red wine, and spices such as rosemary, oregano, thyme, basil, and coriander. Another good reason to eat a variety of fruits and vegetables. From Medical Xpress:

Plant compound found in spices and herbs increases brain connections

Brazilian researchers from D'Or Institute for Research and Education (IDOR), Federal University of Rio de Janeiro (UFRJ) and Federal University of Bahia (UFBA) have demonstrated in laboratory that apigenin, a substance found in parsley, thyme, chamomile and red pepper, improves neuron formation and strengthens the connections between brain cells.

Previous experiments with animals had already shown that substances from the same chemical group as the apigenin, known as flavonoids, positively affect memory and learning. Many studies highlight the potential of flavonoids to preserve and enhance brain function. While the effectiveness of flavonoids for brain health is not an entirely new concept, this research is the first to show the positive effects of apigegin directly on human cells and the first to unraveling its mechanism.

The scientists observed that just by applying apigenin to human stem cells in a dish they become neurons after 25 days - an effect they would not see without the substance. Moreover, the neurons that were formed made stronger and sophisticated connections among themselves after being treated with this natural compound."Strong connections between neurons are crucial for good brain function, memory consolidation and learning", says neuroscientist from IDOR and UFRJ Stevens Rehen, leader author of the paper published today atAdvances in Regenerative Biology.

The research team conducted by Rehen demonstrated that apigenin works by binding to estrogen receptors, which affect the development, maturation, function, and plasticity of the nervous system. This group of hormones is known to delay the onset of psychiatric and neurodegenerative disorders such as schizophrenia, depression, Alzheimer's and Parkinson's disease. However, the use of estrogen-based therapies is limited by the increased risk of estrogen-dependent tumors and cardiovascular problems.

Researchers believe apigenin can be used as an alternative approach on future treatments for neurodegenerative diseases as well as in neuronal differentiation strategies in laboratory. "We show a new path for new studies with this substance", points out Rehen. "Moreover, flavonoids are present at high amounts in some foods and we can speculate that a diet rich in flavonoids may influence the formation of neurons and the way they communicate within the brain."

More reasons to eat a variety of foods - each food will contribute something different, and the effects may be subtle. Here are two healthy foods from plants: orange juice and shiitake mushrooms. From Medical Xpress

Orange juice could help improve brain function in elderly people

Drinking orange juice could help improve brain function in elderly people, according to new research from the University of Reading.The study saw a group of 37 healthy adults (mean age 67 years) consuming 500 ml (just under a pint) of orange juice, daily over an eight week period. At the beginning and end of the eight weeks their memory, reaction time and verbal fluency was measured. These were then combined into one overall score known as 'global cognitive function'. The adults showed an 8% overall improvement in global cognitive function after orange juice consumption compared to a control drink (matched for taste and calories) given during a different eight week period. Although subtle, these improvements are significant. ."

Orange juice is a major source of a group of naturally occurring plant phytochemicals known as flavonoids, being particularly rich in a sub-class of flavonoids, known as flavanones. Recent studies from the School of Chemistry, Food and Pharmacy have shown that flavonoids may improve memory through the activation of signalling pathways in the hippocampus, a part of the brain that is associated with learning and memory. 

Previous Reading research has shown that other flavonoid rich foods such as blueberries are beneficial for cognition. Research is still ongoing to determine the exact mechanisms by which flavonoids may exert benefits to the brain. Several mechanisms haveboosting immune systbeen proposed such as improved blood flow in the brain and protecting neurons against oxidative damage and increasing the efficiency with which neurons transmit signals.

This study was published in April 2015, from Science Daily:  Mushrooms boost immunity, suggests research

Could a mushroom a day help keep the doctor away? A new University of Florida study shows increased immunity in people who ate a cooked shiitake mushroom every day for four weeks.... 52 healthy adults, age 21 to 41, came to the Gainesville campus, where researchers gave them a four-week supply of dry shiitake mushrooms. Participants took the mushrooms home, cleaned and cooked them. Then they ate one, 4-ounce serving of mushrooms each day during the experiment. Through blood tests before and after the experiment, researchers saw better-functioning gamma delta T-cells and reductions in inflammatory proteins.

"If you eat a shiitake mushroom every day, you could see changes in their immune system that are beneficial," said Percival, an Institute of Food and Agricultural Sciences faculty member. "We're enhancing the immune system, but we're also reducing the inflammation that the immune system produces."

Good news for those people who enjoy drinking a glass of orange juice each day. From NPR News:

What's More Nutritious, Orange Juice Or An Orange? It's Complicated

We all could probably eat more fruits and vegetables. But if forced to choose between whole fruit or a glass of juice, which one seems more healthful? The general advice is to opt for the fruit, since juices are stripped of the fiber – which most us don't get enough of — in whole fruit. And let's face it: Most juice contains a lot of sugar, which most of us consume too much of.

So our interest was piqued when we spotted a study suggesting that, when it comes to oranges, juice might actually unlock more carotenoids and flavonoids – both beneficial phytonutrients — than an equivalent amount of fruit.

To figure that out, German and Saudi researchers started with a big batch of fresh navel oranges. They analyzed the fruit in three forms: peeled segments, a mashed-up puree and as juice, both fresh-squeezed and pasteurized. They found that levels of vitamin C and carotenoids were basically the same in the juice and the unprocessed fruit, while levels of flavonoids were significantly lower.

But then the scientists threw their orange test foods into in a test tube model designed to mimic digestion, and that's when things got interesting: Much more of the carotenoids and flavonoids were released from the orange juice than from the fruit slices or mush. The differences were striking: Carotenoid release went up from nearly 11 percent in the fruit to 28 percent in the fresh juice, and up to 39.5 percent in the pasteurized juice. Meanwhile, flavonoids were boosted nearly five-fold in juice compared to fruit.

The findings, which appear in the Journal of Agricultural and Food Chemistry, are scientifically intriguing. For example, the researchers suspect heat may have something to do with the extra carotenoids released in pasteurized juice....That said, the new study "is in line with other studies that have found that nutrients in some fruits and vegetables are more bioavailable when the produce is chopped, mashed, juiced or prepared with oils," Blumberg notes in an email to The Salt.

Indeed, there's a whole avenue of research that is challenging our understanding of how to unleash the nutrition fixed inside fruits and veggies. For instance, as we've reported, we get more beta-carotene from tomatoes when we add a little fat like olive oil, and gently cooking carrots can coax them to release more nutrients. And while cooking broccoli for too long can destroy its antioxidants, chopping it is ideal.

Great reason to add more rosemary and oregano to your diet. From Science Daily:

Rosemary, oregano contain diabetes-fighting compounds

The popular culinary herbs oregano and rosemary are packed with healthful compounds, and now lab tests show they could work in much the same way as prescription anti-diabetic medication, scientists report. In their new study, researchers found that how the herbs are grown makes a difference, and they also identified which compounds contribute the most to this promising trait.

Elvira Gonzalez de Mejia and colleagues point out that in 2012, type-2 diabetes affected more than 8 percent of Americans and cost the country $175 billion. ... Recent research has shown that herbs could provide a natural way to help lower glucose in blood. So Gonzalez de Mejia's team decided to take a closer look.They tested four different herbs, either greenhouse-grown or dried commercial versions, for their ability to interfere with a diabetes-related enzyme, which is also a target of a prescription drug for the disease.

They found that greenhouse herbs contained more polyphenols and flavonoids compared to the equivalent commercial herbs. But this didn't affect the concentration required to inhibit the enzyme. Commercial extracts of Greek oregano, Mexican oregano and rosemary were better inhibitors of the enzyme, required to reduce risk of type-2 diabetes, than greenhouse-grown herbs.

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.

Great news for chocolate lovers. Some other beneficial foods in the study that offer protection from type 2 diabetes: berries, tea, red grapes, wine, parsley, celery, oranges, peppers. From the January 20, 2014 Science Daily:

Ingredients in chocolate, tea, berries could guard against diabetes

Eating high levels of flavonoids including anthocyanins and other compounds (found in berries, tea, and chocolate) could offer protection from type 2 diabetes -- according to research from the University of East Anglia and King's College London. 

Findings published today in the Journal of Nutrition reveal that high intakes of these dietary compounds are associated with lower insulin resistance and better blood glucose regulation.

A study of almost 2,000 people also found that these food groups lower inflammation which, when chronic, is associated with diabetes, obesity, cardiovascular disease, and cancer.