Flavonoids may slow lung function decline due to aging

In continuation of my update on Flvonoids

Previous research has shown that the plant-produced chemicals known as flavonoids have beneficial antioxidant and anti-inflammatory properties. Anthocyanins, the type of flavonoid investigated in the current study, have been detected in lung tissue shortly after being ingested, and in animals models of chronic obstructive pulmonary disease (COPD). The plant chemicals appear to reduce mucus and inflammatory secretions.

However, "the epidemiological evidence on the association between flavonoids and lung function is very scant," said lead study author Vanessa Garcia-Larsen, Ph.D., assistant professor in the Human Nutrition Division of the Department of International Health at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. "So we wanted to investigate whether dietary intake and anthocyanins are associated with lung function decline in middle-age adults."

The researchers analyzed data from 463 adults (average age: 44) who participated in the second and third European Community Respiratory Health Surveys from 2002 to 2012. Those included in the current study completed a dietary questionnaire and underwent spirometry at enrollment and upon follow-up. A common lung function test, spirometry measures the amount of air that a person can forcefully exhale in one second (FEV1), the total amount of air a person can exhale after taking a deep breath (FVC) and the ratio of the two, FEV1/FVC. Participants were then grouped into quartiles based on the amount of anthocyanins they consumed.

The study found individuals in the highest, compared to the lowest, quartile of anthocyanin intake had:

• a slower rate of annual decline in FEV1 than those in the lowest quartile: -9.8 milliliters per year (mL/yr) vs. -18.9 mL/yr.
• a slower rate of annual decline in FVC than those in the lowest quartile: -9.8 mL/yr vs. -22.2 mL/yr.
• a slower rate of annual decline in FEV1/FVC: -0.02/yr.

The researchers also analyzed the association between anthocyanin consumption and lung function in smokers, those who had never smoked and those who quit. The association between high consumption of the flavonoids and reduced lung function decline appeared to be stronger among both never smokers and those who had quit than in the general study population. Among smokers, the study did not find an association between anthocyanin intake and lung function.

The study adjusted for a wide range of factors, including characteristics of participants' diets, gender, height, body mass index and socioeconomic status. Another strength of the study was its inclusion of participants from two countries, Norway and England. The study was limited by its relatively small size and the fact that diets were self-reported.

"Our study suggests that the general population could benefit from consuming more fruits rich in these flavonoids like berries, particularly those who have given up smoking or have never smoked, Dr. Larsen said. "For smokers, quitting remains the best thing they can do to protect their health."

The first European Community Respiratory Health Survey began in 1990 in response to a worldwide increase in asthma prevalence. The scope of the surveys has expanded to include information about the associations between behavioral and environmental factors that might also affect the development of COPD.

Baked rhubarb may help fight cancer....

Rhubarb (herbaceous perennial plants growing from short, thick rhizomes) is a  group of plants that belong to the genus Rheum in the family Polygonaceae.  They have large leaves that are somewhat triangular shaped with long fleshy petioles and small flowers. While the leaves are toxic, the plants have medicinal uses, but most commonly the plant's stalks (see picture, source : Wikipedia) are cooked and used in pies and other foods for their tart flavour.  A number of varieties have been domesticated for human consumption, most of which are recognised as Rheum x hybridum by the Royal Horticultural Society.

Rhubarb (stem & roots) has been used as a strong laxative (the two  - anthraquinones emodin and rhein are responsible). Rubarb has been used in traditional Chinese medicine & medieval Arabic and European prescriptions. The rhizomes ('roots') contain stilbene compounds (including rhaponticin) which seem to lower blood glucose levels in diabetic mice.

Now,  researchers from Biomedical Research Center at Sheffield Hallam University, lead by Dr. Nikki Jordan-Mahy, have come up with new findings. Researchers found that baking British garden rhubarb for 20 minutes dramatically boosted levels of anti-cancer chemicals called polyphenols. Previous research has shown that polyphenols selectively kill or prevent the growth of cancer cells.

This is the first study to examine the benefits of British rhubarb, specifically a variety grown in South Yorkshire. Earlier research has studied Oriental medicinal rhubarb, which has been used in traditional Chinese medicine for thousands of years. 

Baking and slow stewing offered the best maintenance of colour through preservation of anthocyanin and the highest antioxidant capacity. Baking for 20 min provided well-cooked rhubarb with the highest antioxidant capacity and the highest anthocyanin content, which is important for the aesthetic quality of the dish.  

As per the claim by the researchers, LC–MS analysis putatively identified over 40 polyphenol components in raw rhubarb (including anthraquinone, stilbene, anthocyanin and flavonol derivatives.) Baking caused selective effects on the stability of the different polyphenol components. Initially, the yield of all components increased but there was a drastic decline in the relative stability of anthraquinone aglycones with increasing cooking time and initial evidence for the turnover of other anthraquinone derivatives was obtained. Researchers now plan to study the effect of rhubarb's polyphenols on leukemia.....

Ref : Dr. Nikki Jordan-Mahy, et. al., Food Chemistry, Vol. 119, Issue 2, 15 March 2010, Pages 758-764

Spoonful of black rice bran contains more health promoting anthocyanin antioxidants than blueberries

Spoonful of black rice bran contains more health promoting anthocyanin antioxidants than blueberries