The benefits of chocolate during pregnancy
In a study to be presented at the Society for Maternal-Fetal Medicine's annual meeting, The Pregnancy Meeting™, in Atlanta, researchers will present findings from a study titled, High-flavanol chocolate to improve placental function and to decrease the risk of preeclampsia: a double blind randomized clinical trial.
In light of previous studies showing conflicting results regarding the role of chocolate consumption during pregnancy and the risk of preeclampsia, this study set out to evaluate the impact of high-flavanol chocolate. Researchers conducted a single-center randomized controlled trial of 129 women with singleton pregnancy between 11 and 14 weeks gestation who had double-notching on uterine artery Doppler. The pregnant women selected were randomized to either high-flavanol or low-flavanol chocolate. A total of 30 grams of chocolate was consumed daily for 12 weeks and women were followed until delivery. Uterine artery Doppler pulsatility index was at baseline and 12 weeks after randomization. Preeclampsia, gestational hypertension, placenta weight, and birthweight were also evaluated.
The result was that there was no difference in preeclampsia, gestational hypertension, placental weight or birthweight in the two groups; however, the uterine artery Doppler pulsatility index (a surrogate marker of blood velocity in the uterine, placental and fetal circulations) in both groups showed marked improvement that was much greater than expected in general population.
"This study indicates that chocolate could have a positive impact on placenta and fetal growth and development and that chocolate's effects are not solely and directly due to flavanol content," explained Emmanuel Bujold, M.D., one of the researchers on the study who will present the findings. Dr. Bujold and Dr. Sylvie Dodin, principal investigator of the trial, are with the Université Laval Québec City, Canada.
Study shows potential benefit of dark chocolate for liver disease patients
Doctors could soon be prescribing a dose of dark chocolate to help patients suffering from liver cirrhosis and from dangerously high blood pressure in their abdomen, according to new research presented at the International Liver Congress 2010, the Annual Meeting of the European Association for the Study of Liver in Vienna, Austria.
According to the Spanish research, eating dark chocolate reduces damage to the blood vessels of cirrhotic patients and also lowers blood pressure in the liver. Dark chocolate contains potent anti-oxidants which reduce the post-prandial (after-meal) blood pressure in the liver (or portal hypertension) associated with damaged liver blood vessels (endothelial dysfunction). The data also showed that eating dark chocolate may exert additional beneficial effects throughout the whole body. In comparison, white chocolate, which contains no beneficial 'phytochemicals', did not result in the same effects.
Professor Mark Thursz, MD FRCP, Vice Secretary of EASL and Professor of Hepatology, at Imperial College London said: "As well as advanced technologies and high science, it is important to explore the potential of alternative sources which can contribute to the overall wellbeing of a patient. This study shows a clear association between eating dark chocolate and portal hypertension and demonstrates the potential importance of improvements in the management of cirrhotic patients, to minimise the onset and impact of end stage liver disease and its associated mortality risks".
Cirrhosis is scarring of the liver as a result of long-term, continuous damage to the liver . In cirrhosis, circulation in the liver is damaged by oxidative stress and reduced antioxidant systems. After eating, blood pressure in the abdominal veins usually increases due to increased blood flow to the liver.
This is particularly dangerous and damaging to cirrhotic patients as they already have increased blood pressure in the liver (portal hypertension) and elsewhere which, if severe, can cause blood vessel rupture. Thus, eating dark chocolate may ultimately prevent this potential threat to cirrhotic patients.
In this study 21 cirrhotic patients with end stage liver disease (child score 6.9±1.8;MELD 11±4; hepatic venous pressure gradient (HPVG*)16.6±3.8mmHg) were randomised to receive a standard liquid meal. Ten patients received the liquid meal containing dark chocolate (containing 85% cocoa, 0.55g of dark chocolate/Kg of body weight) while 11 patients received the liquid meal containing white chocolate which is devoid of cocoa flavonoids (anti-oxidant properties) according to body weight. HVPG, arterial pressure and portal blood flow (PBF)** were measured at baseline and 30 minutes after meal administration, using a US-Doppler.
Both meals caused a highly significant but similar increase in portal blood flow with a +24% increase in dark chocolate compared to +34% in those patients who received white chocolate. Interestingly, post-prandial hyperaemia*** was accompanied by an increase in HVPG resulting in a statistically significant increase (17.3±3.6mmHg to 19.1±2.6mmHg, p=0.07) for those patients eating dark chocolate and those receiving white chocolate (16.0±4.7mmHg to 19.7±4.1mmHg, p=0.003). Post-prandial increase in HVPG was markedly reduced in patients receiving dark chocolate (+10.3±16.3% Vs +26.3±12.7%, p=0.02).
*HVPG is blood pressure in the liver
**PBF refers to blood flow in the liver
***Hyperaemia refers to increase blood flow to tissues
People with artery problems walked a longer and farther after eating dark chocolate
In a small study, people with artery problems in their legs walked a little longer and farther when they ate dark chocolate – a food rich in polyphenols, according to new research in Journal of the American Heart Association.
Peripheral artery disease (PAD) is a narrowing of the peripheral arteries to the legs, stomach, arms, and head – most commonly in the arteries of the legs. Reduced blood flow can cause pain, cramping or fatigue in the legs or hips while walking.
In this pilot study of patients with PAD (14 men and six women, ages 60-78), study participants increased their ability to walk unassisted after eating dark chocolate, compared to when they ate milk chocolate. The authors suggest that compounds found in cocoa – polyphenols – may reduce oxidative stress and improve blood flow in peripheral arteries.
The patients were tested on a treadmill in the morning and again two hours after eating 40 grams of dark and milk chocolate (about the size of an average American plain chocolate bar) on separate days. The dark chocolate in the study had a cocoa content of more than 85 percent, making it rich in polyphenols. The milk chocolate, with a cocoa content below 30 percent, had far fewer polyphenols.
After eating the dark chocolate, they walked an average 11 percent farther and 15 percent longer (almost 12 meters/39 feet farther and about 17 seconds longer) than they could earlier that day. But distance and time didn’t improve after eating milk chocolate.
The improvements were modest. Still, the benefit of dark chocolate polyphenols is “of potential relevance for the quality of life of these patients,” said Lorenzo Loffredo, M.D., the study’s co-author and assistant professor at the Sapienza University of Rome in Italy.
Levels of nitric oxide — a gas linked to improved blood flow — were higher when participants ate dark chocolate. Other biochemical signs of oxidative stress were also lower. Based on these observations and other laboratory experiments, the authors suggest that the higher nitric oxide levels may be responsible for dilating peripheral arteries and improving walking independence.
“Polyphenol-rich nutrients could represent a new therapeutic strategy to counteract cardiovascular complications,” said, Francesco Violi, M.D., study senior author and professor of internal medicine at the Sapienza University of Rome.
The researchers said the improvements linked to these compounds in dark chocolate need to be confirmed in a larger study involving long-term consumption. The current study lacked a placebo group, and patients knew which kind of chocolate they were given, a factor that could influence the results.
American Heart Association spokesperson Dr. Mark Creager noted that it’s far too early to recommend polyphenols or dark chocolate for cardiovascular health.
“Other investigations have shown that polyphenols including those in dark chocolate may improve blood vessel function. But this study is extremely preliminary and I think everyone needs to be cautious when interpreting the findings,” said Creager, who is director of the Vascular Center at Brigham and Women’s Hospital and a professor of medicine at Harvard Medical School in Boston.
“We know from other studies of antioxidants — vitamin C and vitamin E for example — that these interventions have not gone on to show improvement in cardiovascular health.”
Chocolate adds calories to the diet. The American Heart Association recommends that men consume no more than 150 calories per day from added sugars (9 teaspoons) and women should consume no more than 100 calories (6 teaspoons) from added sugar per day and 5 percent -6 percent of calories from saturated fat. A typical American chocolate bar provides 94 calories from sugar (24 grams) and 8 grams of saturated fat.
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.