Aware of Your Own Caffeine Safe Level?
Business people can't go on without coffee breaks now and then just to pep up. But, watch out, caffeine can be fatal, as to a 20-year-old Japanese male who died of caffeine addiction last year.
This young man in Kyushu had a habit of drinking a caffeine-containing soft drink and died of an overdose of caffeine. Professor Shinichi Kubo of Fukuoka University warns habitual heavy coffee drinkers are liable to risk their lives.
That said, there aren't clearcut standard caffeine consumption limits per day in Japan. In fact, the Ministry and the Food Safety Commission are collecting data on caffeine's damages on health toward working out a criteria on caffeine intake.
Elsewhere in the world, some countries do have daily caffeine consumption guidelines already set out. The European Food Safety Authority barred on May 27, 2015, a table showing caffeine intake levels by weight. It shows adults weighing 40kg may take up to 120mg each time and those weighing 80kg 240mg every time, etc.
Meanwhile, the All-Japan Coffee Association compiled their own tables spelling out caffeine intake limits and listing various caffeine-containing foods, drinks, supplements, etc.
Based on the data, a slim woman of 40kg can step over her per-time intake limits with a can coffee or a bottle of energy drink. She should stick to any tranquilizer with no caffeine content when she needs one. Those drugs to keep you awake are the most caffeine-rich of all OTC drugs.
Some are more caffeine-sensitive than others; male are more so than female; children the highest. A recent study from Tsukuba University shows certain genes are responsible for various levels of caffeine-sensitivity. One out of four Japanese has genes that induce anxiety and other similar symptoms with an intake of 150mg of caffeine.
Similarly, a US study (Molecular Psychiatry. 2015；20:647-656.）has identified 6 specific genes that affect caffeine metabolism.
All points to the characteristics of caffeine-rich foods and drinks that threaten our health. Beware, dear folks.