Eating flavonoids protects men against Parkinson’s disease

Men who eat flavonoid-rich foods such as berries, tea, apples and red wine significantly reduce their risk of developing Parkinson’s disease, according to new research by Harvard University and the University of East Anglia (UEA).

Published April 4 in the journal Neurology®, the findings add to the growing body of evidence that regular consumption of some flavonoids can have a marked effect on human health. Recent studies have shown that these compounds can offer protection against a wide range of diseases including heart disease, hypertension, some cancers and dementia.

This latest study is the first study in humans to show that flavonoids can protect neurons against diseases of the brain such as Parkinson’s.

Around 130,000 men and women took part in the research. More than 800 had developed Parkinson’s disease within 20 years of follow-up. After a detailed analysis of their diets and adjusting for age and lifestyle, male participants who ate the most flavonoids were shown to be 40 per cent less likely to develop the disease than those who ate the least. No similar link was found for total flavonoid intake in women.

The research was led by Dr Xiang Gao of Harvard School of Public Health in collaboration with Prof Aedin Cassidy of the Department of Nutrition, Norwich Medical School at UEA.

“These exciting findings provide further confirmation that regular consumption of flavonoids can have potential health benefits,” said Prof Cassidy.

“This is the first study in humans to look at the associations between the range of flavonoids in the diet and the risk of developing Parkinson’s disease and our findings suggest that a sub-class of flavonoids called anthocyanins may have neuroprotective effects.”

Prof Gao said: “Interestingly, anthocyanins and berry fruits, which are rich in anthocyanins, seem to be associated with a lower risk of Parkinson’s disease in pooled analyses. Participants who consumed one or more portions of berry fruits each week were around 25 per cent less likely to develop Parkinson’s disease, relative to those who did not eat berry fruits. Given the other potential health effects of berry fruits, such as lowering risk of hypertension as reported in our previous studies, it is good to regularly add these fruits to your diet.”

Flavonoids are a group of naturally occurring, bioactive compunds found in many plant-based foods and drinks. In this study the main protective effect was from higher intake of anthocyanins, which are present in berries and other fruits and vegetables including aubergines, blackcurrants and blackberries. Those who consumed the most anthocyanins had a 24 per cent reduction in risk of developing Parkinson’s disease and strawberries and blueberries were the top two sources in the US diet.

The findings must now be confirmed by other large epidemiological studies and clinical trials.

Parkinson’s disease is a progresssive neurological condition affecting one in 500 people, which equates to 127,000 people in the UK. There are few effective drug therapies available.

Dr Kieran Breen, director of research at Parkinson’s UK said: “This study raises lots of interesting questions about how diet may influence our risk of Parkinson’s and we welcome any new research that could potentially lead to prevention.

“While these new results look interesting there are still a lot of questions to answer and much more research to do before we really know how important diet might be for people with Parkinson’s.”

 

Reference

Gao X, Cassidy A, Schwarzschild MA, Rimm EB, Ascherio A. Habitual intake of dietary flavonoids and risk of Parkinson disease. Neurology, 2012 DOI: 10.1212/WNL.0b013e31824f7fc4

 

Is Estrogen Going to Your Head?

Growing deposits of bone in the skull means your hormones are out of whack, warns researcher Prof. Israel Hershkovitz at Tel Aviv University 

Girls are growing up faster than ever — and not only when it comes to their taste in fashion and music. Their bodies are reaching puberty at an increasingly earlier age, and this trend to rapid maturity continues through women’s adult lives. That’s bad news, according to Tel Aviv University researchers. Women today are more likely to develop Hyperostosis Frontalis Interna (HFI), a hormonal condition once typically found in post-menopausal women, earlier and more frequently than the female population a century ago.

Women’s hormonal balances are changing and taking a physical toll, says  and his graduate student Hila May of TAU’s Sackler Faculty of Medicine, together with Dr. Natan Peled of Carmel Medical Center in Haifa. That balance is being affected by the hormones we now consume in our food and by our changing fertility patterns, such as having children later in life. Women today are 2.5 times more likely to develop HFI than they were 100 years ago, the study found.

Their research recently appeared in the American Journal of Human Biology 

Prof. Israel Hershkovitz

Sounding the alarm

HFI occurs when a hormonal imbalance leads to the growth of lesions, or bone masses, in the inner skull. This may lead to symptoms such as chronic headaches, weight gain, and thyroid irregularities, and is suspected to have multiple causes, including lifestyle, fertility habits, nutrition, and environment.

To track the growing prevalence of HFI, Prof. Hershkovitz and fellow researchers compared 992 historic female skulls from museum collections aged 20 to 90 years with CT scans of 568 living female participants ranging from 20 to 103 years old. Not only was prevalence of HFI found to be 2.5 times higher in the latter group, but the researchers also discovered that the average age of women who suffered from HFI had fallen drastically.

An age-dependent condition, HFI was once known to primarily strike post-menopausal women, who had then been exposed moderate levels of estrogen throughout their lives. Now it is appearing as well in pre-menopausal women, who have been exposed to higher levels of estrogen earlier in their lifetimes.

Their survey found that only 11 percent of 19-20th century women in the age range 30-39 had HFI. However, in the modern sample, 40 percent of women in that age group were found to be developing the condition. Any number of factors could be to blame, May says. Hormones added to food are one culprit, but not the only one. Women are now having fewer children and getting pregnant later in life. The period of time women breastfeed has also been shortened considerably, from three to four years a century ago to an average of less than six months today. Women are also consuming additional amounts of hormones through birth control medications. It’s now common for girls to be on “the pill” in their early teenage years.

There is currently no cure for HFI, but detection of the condition remains important, says Prof. Hershkovitz, who was among the first scientists to investigate the development of HFI in the human skull. “It’s an alarm within the human body, telling you that your body is out of balance and there is a pathological process going on,” he explains. It can also be a symptom of metabolic diseases.

Not just for women

Although most frequently found in the female population, HFI is not an exclusively female condition. Prof. Hershkovitz points to the case of Farinelli, a famous male opera singer in the 18th century, who suffered from HFI probably as a result of castration to preserve his falsetto voice.

Prof. Hershkovitz, Dr. Peled and May discovered a high prevalence of HFI in men who have been treated for prostate cancer. One of the treatments for prostate cancer, explains Prof. Hershkovitz, is chemical castration. Since the cancer itself feeds on testosterone, this treatment option literally starves the disease, but leads to higher levels of estrogen in the body.

Prof. Hershkovitz does not counsel against the prostate treatment, however — it is part of the physiological “cost-benefit” balance of the body. “If you treat one system in the body, another must pay,” he says. In this case, he says, it’s worth the price.

 

Reference

May H, Peled N, Dar G, Abbas J, Hershkovitz I. Hyperostosis frontalis interna: What does it tell us about our health? Am J Hum Biol 2011; 23 (3): 392-397.