Shigeko Kagawa, Japan's oldest woman, has passed away at the age of 115. Before her death, she shared the simple secret to her long life.According to her, regular walking and keeping her brain active helped her achieve such a long life. Following a routine and living a normal daily life were also part of her lifestyle.Shigeko Kagawa, a resident of Yamatokoriyama City in Nara Prefecture, passed away Thursday at the age of 115 years and 91 days, reports The Independent.Regarding longevity, she sai...