記事内の引用について
Young man suffered heart failure after having four cans of energy drink every day for two years(Evening Standard)より　
https://www.standard.co.uk/news/health/young-man-suffered-heart-failure-after-having-four-cans-of-energy-drink-every-day-for-two-years-b929988.html
Doctors issue health warning after student with four-a-day energy drink habit is left with HEART FAILURE after spending two months in hospital(Daily Mail)より
https://www.dailymail.co.uk/news/article-9476779/Doctors-issue-health-warning-students-four-day-energy-drink-habit.html
国内初、カフェイン中毒死　エナジードリンク日常的に大量摂取か(産経ニュース)より
https://www.sankei.com/life/news/151222/lif1512220003-n1.html
食品中のカフェインについて(食品安全委員会サイト)より
https://www.fsc.go.jp/factsheets/index.data/factsheets_caffeine.pdf