Raisins and Green Tea Can Help your Teeth and Gums

Dr. Christine D. Wu is a professor and Associate Dean for Research at the University of Illinois at Chicago College of Dentistry.  For several years she has studied compounds that can fight the bacteria that cause cavities and gum disease.  She has looked at antioxidant compounds in raisins and found that oleanolic acid in raisins inhibits the growth of two species of  oral bacteria – Streptoccocus mutans, which causes cavities, and Porphyromonas gingivalis, which causes periodontal (gum) disease.  The compound blocked S. mutans  from adhering to tooth surfaces.  Adherence is crucial for bacteria to form dental plaque, the sticky biofilm  consisting of oral bacteria that accumulates on teeth.  When you eat a sugary meal, these bacteria release acids that erode the tooth enamel.   “Raisins are perceived as sweet and sticky, said Dr. Wu,  “and any food that contains sugar and is sticky is assumed to cause cavities. But our study suggests the contrary.  Phytochemicals in raisins may benefit oral health by fighting bacteria that cause cavities and gum disease.”   However, bran cereals that have added sugar and raisins are not the best.  Finding a cereal without added sugar such as oatmeal, and adding raisins to it would be better. Raisins can also be enjoyed as a snack, along with nuts, during the day. People with diabetes should test their blood sugar values if they snack on raisins, as data about this has been controversial.  

The ability of tea to fight dental caries has been suggested for decades.  The polyphenols in tea, especially EGCG (epigallocatechin gallate) have been shown to inhibit dental plaque accumulation, but the exact mechanisms are not clear.  Dr. Wu and her colleagues think that EGCG suppresses genes in S. mutans  and prevents the initial attachment of this bacterium to the teeth, and thus the formation of mature biofilms.  The effects of ECGC  on other  properties of S. mutans were also studied.  The research showed a dose dependent inhibition of the initial attachment of S. mutans and also an effect on the genes of this bacterium.  These findings suggest that ECGC may represent a novel and natural way to inhibit biofilm formation on the teeth.   ECGC is also being studied in laboratories throughout the world for its properties to combat many systemic diseases.  Stay tuned.

 You may be aware that green tea has much more ECGC than black tea, although they come from the same plant.  Researchers have warned that excessive amounts of ECGC found in some supplements can lead to toxicity and liver damage, so it is prudent to avoid high doses of this supplement. Brew green tea and swish it around in your mouth before swallowing.  Enjoy one or more cups a day, depending on your tolerance for caffeine, Green tea has about 1/3 to 1/2 the caffeine as coffee.  Kukicha green tea is made of the stems, stalks and twigs of the tea plant and is naturally low in caffeine. Powdered green tea, such as matcha, is considerably stronger. Water to brew a cup of green tea should be less than boiling temperature, around 150 to 160  degrees F . 

May all be well on your next trip to the dentist!

Sadja Greenwood, MD, MPH

Help the environment by keeping your cell phone! And more

You have read of the new report on climate change from the U.S. government, saying that what the earth is experiencing is unlike anything in the past, that the global average temperature is much higher and is rising more rapidly than anything modern civilization has ever gone through..  This warming trend can only be explained by human activity.  Our country could lose hundreds of billions of dollars, or more than 10% of its GPD by the end of the century.  Rising oceans can flood many coastal cities and towns, including Bolinas. The US Global Change Research Program  is a team of 13 federal agencies and was put together by a group of 1,000 people, including 300 leading scientists, roughly half from outside the government.

There are many suggested steps that people can take, and I will list some of them.  The first came from a New York Times article this week, concerning cell phones.  The problem isn’t the power needed to charge your phone (although that can add up)  “but the tremendous energy needed to mine 60 plus metals and assemble them into a new device.  A 2015 study found that producing an iPhone 6 released the equivalent of 178 pounds of carbon dioxide – about as much as running a modern refrigerator for a year.” Most people change cell phones every 2 years.  Lofti Belkhir, an entrepreneur and engineering professor at McMaster University in Hamilton, Ontario, says that cell phone business models promote frequent upgrades while masking the true financial and environmental costs of new phones. His research suggests: hang on to your phone as long as possible.  Extend its life by fixing it when things break, cleaning the charging port and swapping out dying batteries.  If you must replace your phone, recycle your old one and consider buying a used one.  Purchasing fewer new phones will send a message to industry that it needs to change.

Many of us feel there isn’t enough we can do as an individual to address climate change.  That’s why it’s important to join with others in effective organizations.  350.org is an international organization founded by environmentalist Bill McKibben of Middlebury College to work on these goals: keep carbon in the ground, build a new and more equitable low carbon economy, and pressure governments into limiting emissions. If you look at 350.org you can get on their mailing list for information. 

Be aware that California is joining Hawaii in going carbon-free by 2045 by having all electricity free of fossil fuel origin. This is amazing!  Salt Lake City, Atlanta, San Diego, Pittsburg and Portland have all announced they are going 100% renewable.  

 Here are other things an individual can do: Drive less, carpool, use a fuel efficient car, take a train or bus rather than a plane whenever possible.   Eat less meat – because almost 15% of human induced greenhouse gases come from livestock. Waste less food  - buy only what you need and take your own container to a restaurant to wrap up what’s left over.  Install rooftop or backyard solar panels.  Use water carefully, by planting native plants instead of a lawn.  You and your state are powerful and you should feel effective in making these moves.  Basically they are for your children and grandchildren. If I have left out moves that you feel are important, please let me know on my website and I’ll print them in my next column.

Sadja Greenwood, MD,  MPH   leave me a comment!