Drinking two cups of hot chocolate a day helps boost memory among the elderly, a study has suggested.
Research on pensioners found that drinking cocoa improved blood flow, which has been linked to healthier brains and improved cognition. The study led by Harvard researchers examined 60 people with an average age of 73, who did not have dementia.
Participants drank two cups of hot cocoa per day for 30 days and did not eat any other chocolate. They were given memory and thinking skills tests, as well as ultrasound tests to measure the amount of blood flow to the brain.
Of the 60 participants, 18 had impaired blood flow at the start of the study. The results of the study showed that for those participants, there were improvements in blood flow tothe brain and in tests of their working memory.
After a month, they experienced an 8.3 per cent improvement in flow to working areas of the brain. Test scores of their working memory also improved, with recall times falling from an average of 167 seconds to 116 seconds.
Dr Farzaneh Sorond, from Harvard Medical School in Boston, who led the study reported online in the journal Neurology, said: "We're learning more about blood flow in the brain and its effect on thinking skills.
"As different areas of the brain need more energy to complete their tasks, they also need greater blood flow. This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer's."
There were no such improvements for participants with regular blood flow, according to the study by the National Institute on Aging and the National Heart, Lung, and Blood Institute.
MRI scans were also performed on 24 participants, to look for tiny areas of brain damage. The scans showed that people with impaired blood flow were more likely to have these areas of brain damage.
Dr Doug Brown, Director of Research and Development for the Alzheimer’s Society, said:
“‘We know that poor blood flow can affect people’s brain power because they don’t have enough fuel in their brain cells to complete tasks efficiently.” “From this small but interesting study, it seems that cocoa helps improve blood supply to the brain, therefore having a knock on effect of improving people’s cognition.”
He said it was not known whether drinking cocoa had any impact on dementia.
"Although this could be good news for those who enjoy a relaxing hot chocolate before bed, we do need further research to better our understanding of the link between cocoa and cognition, and also whether it has any impact on dementia,” he said.
In an accompanying editorial in the journal Neurology, Paul Rosenberg, from Johns Hopkins School of Medicine in Baltimore, said: “More work is needed to prove a link between cocoa, bloodflow problems and cognitive decline. But this is an important first step that could guide future studies.”
Dr Simon Ridley, head of research at charity Alzheimer’s Research UK, said: “This small study adds to a wealth of existing evidence linking vascular problems and poorer cognition. “A cocoa-based treatment would likely be very popular, but it’s too soon to draw any conclusions about its effects.
“One drawback of this study is the lack of a control group for comparison, and we can’t tell whether the results would have been different if the participants drank no cocoa at all. This research took place over a very short space of time, and it would be useful to see longer studies to investigate cocoa’s long-term effects.”
Dr Ridley said with dementia posing a major medical challenge, research into ways to prevent the condition was vital. He added: “Poor vascular health is a known risk factor for dementia, and understanding more about the links between vascular problems and declining brain health could help the search for new treatments and preventions.”
In recent years, many researchers have focused their attention on how chocolate, or its ingredients, may be beneficial to health. Studies have linked cocoa and dark chocolate in particular with positive effects on conditions such as heart disease, reducing the risks of cancer and lowering blood pressure.
Arthritis sufferers at higher risk of fatal blood clots People with rheumatoid arthritis have a higher risk of suffering potentially fatal leg and lung blood clots, research suggests. The disease causes pain and swelling in the joints, with patients finding movement very painful.
Now experts writing online in the Annals Of The Rheumatic Diseases have found that people with the disease have a three times higher risk of deep vein thrombosis in the legs than those without.
Sufferers also have a two-fold increased risk of pulmonary embolism in the lungs. The team, from the China Medical University in Taiwan, studied almost 30,000 patients. Professor Alan Silman, medical director of Arthritis Research UK, said: “This study is the first suggesting rheumatoid arthritis, which is a disorder which is associated with widespread inflammation, can be a risk factor [to blood clots].”
Blood sugar dementia link
Higher blood sugar levels are linked to an increased risk of dementia, even in people who do not have diabetes, researchers have found.
A study by the University of Washington found that blood sugar levels looked at over a five-year period were associated with a rising risk of developing dementia in more than 2,000 patients followed.
In people without diabetes, the risk of dementia was 18 per cent higher in those with a higher blood sugar level compared to those with lower levels. In people with diabetes, whose blood sugar levels are generally higher, dementia risk was 40 per cent higher compared to those with lower levels.
More on the cocoa study
So, should you start stocking up on Swiss Miss?
Not necessarily. The research is too limited to prove that cocoa directly boosted the brainpower of those with lower blood flow in the brain, and the findings don't say anything about long-term effects.
In addition, drinking two cups of a sweet drink each day could cause or worsen obesity, which is linked to declines in brain function.
"Before we recommend cocoa, it's important to go back and figure out what's in it that's doing this and make sure it's sustainable," said study author Dr. Farzaneh Sorond, an assistant professor of neurology at Harvard Medical School. "I'd prefer people wait until we figure out how to get the benefit without the calories, sugar and fat that comes in cocoa."
Still, the research is allowing scientists to get a better handle on a somewhat mysterious topic -- the flow of blood in the brain. The brain cells known as neurons need fuel to do their job, and blood provides it.
"The brain is a greedy organ, with just 2 percent of body mass and 20 percent of energy requirements," explained Andrew Scholey, director of the Center for Human Psychopharmacology at Swinburne University in Australia. "It requires a constant supply of blood to deliver the metabolic fuels of glucose and oxygen. Blood flow to the brain reduces with aging, and this correlates with cognitive [mental] decline."
Previous research has linked cocoa, which is found in chocolate, to health benefits. In the new study, researchers wanted to find out if it would affect blood flow in the brain, and brainpower itself.
The researchers recruited 60 people with an average age of 73 and assigned them to 30 days of either drinking cocoa rich in flavanol -- which is linked to improved blood flow -- or drinking cocoa low in flavanol. The special cocoa was provided by Mars Inc., but the company didn't have any other role in the study.
Eighteen people had impaired blood flow in the brain when the study began. Almost all of the 60 participants had high blood pressure and half had a form of diabetes. Almost all -- 85 percent -- were white. Brain blood flow improved by an average of 8 percent by the end of the study in those participants whose levels were low at the beginning.
There was no effect among the others who had normal blood flow. Those with lower blood flow also performed better on memory tests, improving the time they needed to complete tasks (dropping from an average of 167 seconds to 116 seconds), but it's not clear what this would mean in day-to-day life. Again, those with regular blood flow levels didn't improve.
The levels of flavanol in the drinks didn't seem to matter, suggesting that flavanol has no effect or works in very small doses, Sorond said. It's also possible that another ingredient, like caffeine, is responsible for the changes, she said. It's hard to know exactly what's happening in the brain, she said, but it may have something to do with the widening of vessels so more blood gets through.
The Alzheimer's Association issued a statement on the study Wednesday, noting several caveats about the research. "This is a very small and very preliminary study, and it is not well-designed as a test of an intervention or therapy," said Maria Carrillo, vice president of medical and scientific relations at the association.
"No one should start drinking cocoa with the expectation that it will provide cognitive benefits based on this study." "There was no control group in this study to compare to the group that drank the cocoa," Carillo continued. Also, "factors that could possibly impact brain blood flow and/or cognition were not controlled, tracked or accounted for -- as far as we can see in the article."
Can Ozan Tan, an instructor at the Harvard Clinical and Translational Science Center who co-wrote a journal commentary about the research, said the study is important for more than what it seems to reveal about cocoa. It also shows a "convincing link" between blood flow in the brain, the physical makeup of the brain and brainpower, Tan said, and this connection could lead to better treatments for brain diseases and declines in brainpower.
The study was published in the Aug. 7 (2013) online issue of the journal Neurology.
Read more about Alzheimer's disease here: Alzheimer's Disease
Read more about dementia here: Dementia
SOURCES: Farzaneh Sorond, M.D., Ph.D., neurologist, Brigham and Women's Hospital, and assistant professor, neurology, Harvard Medical School, Boston; Andrew Scholey, Ph.D., director, Center for Human Psychopharmacology, Swinburne University, Melbourne, Australia; Can Ozan Tan, Ph.D., instructor, Harvard Clinical and Translational Science Center, Boston; Maria Carrillo, Ph.D., vice president, medical and scientific relations, Alzheimer's Association; Aug. 7, 2013, Neurology, online