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

Naturally occurring cocoa flavanols are largely destroyed by most cocoa processing methods. The cocoa flavanol drink test materials used in these studies supplied by Mars, Incorporated were extracted using a patented process from fresh cocoa beans. Credit: Mars, Incorporated

14 sept 2015--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 ageing 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. "With the world population getting older, the incidence of cardiovascular disease, heart attacks and stroke will only increase," says Professor Malte Kelm, Professor of Cardiology, Pulmonary Diseases and Vascular Medicine at University Hospital Düsseldorf and Scientific Director of FLAVIOLA. "It is therefore pivotal that we understand the positive impact diet can have on cardiovascular disease risk. As part of this, we want to know what role flavanol-containing foods could play in maintaining the health of the heart and blood vessels."
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—but, for the most part, these investigations have focused on high-risk individuals like smokers and people that have already been diagnosed with conditions like hypertension and coronary heart disease. 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,  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 mmHg 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. The researchers also measured cholesterol levels in the study groups, in addition to vasodilation, arterial stiffness and blood pressure.
"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." Other longer-term studies, such as the 5-year COcoa Supplement and Multivitamin Outcomes Study (COSMOS) of 18,000 men and women, are now underway to investigate the health potential of flavanols on a much larger scale.


Provided by University Hospital Düsseldorf

Dietary cocoa flavanols reverse age-related memory decline, study shows

Dietary cocoa flavanols -- naturally occurring bioactives found in cocoa -- reversed age-related memory decline in healthy older adults, according to a study led by Columbia University Medical Center scientists. A cocoa flavanol-containing test drink prepared specifically for research purposes was produced by the food company Mars, Incorporated, which also supported the research, using a proprietary process to extract flavanols from cocoa beans. Most methods of processing cocoa remove many of the flavanols found in the raw plant. Credit: Mars, Incorporated

28 oct 2014--Dietary cocoa flavanols—naturally occurring bioactives found in cocoa—reversed age-related memory decline in healthy older adults, according to a study led by Columbia University Medical Center (CUMC) scientists. The study, published today in the advance online issue of Nature Neuroscience, provides the first direct evidence that one component of age-related memory decline in humans is caused by changes in a specific region of the brain and that this form of memory decline can be improved by a dietary intervention.

As people age, they typically show some decline in cognitive abilities, including learning and remembering such things as the names of new acquaintances or where one parked the car or placed one's keys. This normal age-related memory decline starts in early adulthood but usually does not have any noticeable impact on quality of life until people reach their fifties or sixties. Age-related memory decline is different from the often-devastating memory impairment that occurs with Alzheimer's, in which a disease process damages and destroys neurons in various parts of the brain, including the memory circuits.

Previous work, including by the laboratory of senior author Scott A. Small, MD, had shown that changes in a specific part of the brain—the dentate gyrus—are associated with age-related memory decline. Until now, however, the evidence in humans showed only a correlational link, not a causal one. To see if the dentate gyrus is the source of age-related memory decline in humans, Dr. Small and his colleagues tested whether compounds called cocoa flavanols can improve the function of this brain region and improve memory. Flavanols extracted from cocoa beans had previously been found to improve neuronal connections in the dentate gyrus of mice.

Dr. Small is the Boris and Rose Katz Professor of Neurology (in the Taub Institute for Research on Alzheimer's Disease and the Aging Brain, the Sergievsky Center, and the Departments of Radiology and Psychiatry) and director of the Alzheimer's Disease Research Center in the Taub Institute at CUMC.

A cocoa flavanol-containing test drink prepared specifically for research purposes was produced by the food company Mars, Incorporated, which also partly supported the research, using a proprietary process to extract flavanols from cocoa beans. Most methods of processing cocoa remove many of the flavanols found in the raw plant.

The brain area outlined in yellow is the hippocampus; the dentate gyrus is shown in green and the entorhinal cortex in purple. Previous work, including by the laboratory of senior author Scott A. Small, M.D., had shown that changes in a specific part of the brain's hippocampus -- the dentate gyrus -- are associated with normal age-related memory decline in humans and other mammals. The dentate gyrus is distinct from the entorhinal cortex, the hippocampal region affected in early-stage Alzheimer's disease. Credit: Lab of Scott A. Small, M.D.

In the CUMC study, 37 healthy volunteers, ages 50 to 69, were randomized to receive either a high-flavanol diet (900 mg of flavanols a day) or a low-flavanol diet (10 mg of flavanols a day) for three months. Brain imaging and memory tests were administered to each participant before and after the study. The brain imaging measured blood volume in the dentate gyrus, a measure of metabolism, and the memory test involved a 20-minute pattern-recognition exercise designed to evaluate a type of memory controlled by the dentate gyrus.

"When we imaged our research subjects' brains, we found noticeable improvements in the function of the dentate gyrus in those who consumed the high-cocoa-flavanol drink," said lead author Adam M. Brickman, PhD, associate professor of neuropsychology at the Taub Institute.

The high-flavanol group also performed significantly better on the memory test. "If a participant had the memory of a typical 60-year-old at the beginning of the study, after three months that person on average had the memory of a typical 30- or 40-year-old," said Dr. Small. He cautioned, however, that the findings need to be replicated in a larger study—which he and his team plan to do.

Flavanols are also found naturally in tea leaves and in certain fruits and vegetables, but the overall amounts, as well as the specific forms and mixtures, vary widely.

The dentate gyrus is distinct from the entorhinal cortex, the hippocampal region affected in early-stage Alzheimer's disease. Previous work, including by the laboratory of senior author Scott A. Small, M.D., had shown that changes in a specific part of the brain's hippocampus -- the dentate gyrus -- are associated with normal age-related memory decline in humans and other mammals. Credit: Lab of Scott A. Small

The precise formulation used in the CUMC study has also been shown to improve cardiovascular health. Brigham and Women's Hospital in Boston recently launched an NIH-funded study of 18,000 men and women to see whether flavanols can help prevent heart attacks and strokes.

The researchers point out that the product used in the study is not the same as chocolate, and they caution against an increase in chocolate consumption in an attempt to gain this effect.

Two innovations by the investigators made the study possible. One was a new information-processing tool that allows the imaging data to be presented in a single, three-dimensional snapshot, rather than in numerous individual slices. The tool was developed in Dr. Small's lab by Usman A. Khan, an MD-PhD student in the lab, and Frank A. Provenzano, a biomedical engineering graduate student at Columbia. The other innovation was a modification to a classic neuropsychological test, allowing the researchers to evaluate memory function specifically localized to the dentate gyrus. The revised test was developed by Drs. Brickman and Small.

Besides flavanols, exercise has been shown in previous studies, including those of Dr. Small, to improve memory and dentate gyrus function in younger people. In the current study, the researchers were unable to assess whether exercise had an effect on memory or on dentate gyrus activity. "Since we didn't reach the intended VO2max (maximal oxygen uptake) target," said Dr. Small, "we couldn't evaluate whether exercise was beneficial in this context. This is not to saythat exercise is not beneficial for cognition. It may be that older people need more intense exercise to reach VO2max levels that have therapeutic effects."

More information: Enhancing dentate gyrus function with dietary flavanols improves cognition in older adults, Nature Neuroscience, DOI: 10.1038/nn.3850

Provided by Columbia University Medical Center

Cocoa Can Reduce Levels of Inflammatory Biomarkers


Study suggests that cocoa consumption may help protect high-risk patients against atherosclerosis

FRIDAY, Oct. 23 (HealthDay News) -- In patients at high risk of cardiovascular disease, cocoa may significantly decrease levels of some inflammatory biomarkers, suggesting that the flavonoids in cocoa may help protect against atherosclerosis, according to a study in the Nov. 1 issue of the American Journal of Clinical Nutrition.

Maria Monagas, a researcher at the University of Barcelona in Spain, and colleagues assigned 42 volunteers (19 men and 23 women; mean age, 69.7 years) to receive either 40 grams of cocoa powder mixed with 500 milliliters of skim milk and then skim milk alone for two periods of four weeks.

The researchers found no significant group differences in the expression of adhesion molecules on T lymphocyte surfaces. However, they found significantly lower expression of very late activation antigen-4, CD-40, and CD36 in monocytes, and lower concentrations of soluble endothelium-derived adhesion molecules P-selectin and intercellular adhesion molecule-1 in serum after the cocoa and milk intake.

"Another positive outcome of our study was the higher high-density lipoprotein-cholesterol concentration after cocoa and milk intake than after milk intake," the authors write. "Although outcomes on lipid metabolism from cocoa feeding trials are still scarce, this finding seems to be in accordance with that of several studies that have reported higher high-density lipoprotein-cholesterol concentrations after cocoa or chocolate intake but no changes in low-density lipoprotein cholesterol."

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