A documentary has claimed purple sweet potato can help you live until 100. Professor Craig Wilcox has been studying the Okinawan diet for the last decade and believes a key factor in their vigorous health can be attributed to the vegetable. Sweet potatoes have been a go to food for the Okinawans for a long time, revealed the professor. They are easy to grow and they are very economical to producer and they are powerhouses of nutrition. THE ART OF HAPPINESS SERIES PURPLE YAM & PURPLE SWEET POTATO THE SECRET TO LIVING UNTIL 100 A QUICK GUIDE IN STRETCHING FELXIBILITY AND MUSCLE TONE CHROMOTHERAPY COLOURS AND WELL-BEING HAPPINESS GUIDE HOW TO BOOST YOUR SEROTONIN LEVELAbout the AuthorPAUL MIHALACHE IS A ROMANIAN WRITER, BORN 04/06/1986, WHO LIVES IN LONDON, UNITED KINGDOM, SINCE 2010. WITH GREAT EXPERIENCE AS PE TEACHER, PERSONAL TRAINER AND FITNESS INSTRUCTOR HE STARTED IN 2015 TO WRITE THE ART OF HAPPINESS SERIES. THE BOOKS ARE AIMING TO DELIVER INFORMATION ON HOW TO ACHIEVE A HEALTHY LIFESTYLE.