Bryan Johnson has claimed that frequent international travel may be harmful for the human body, calling it “barbaric” in a recent X post. Sharing data from his trip to Asia, Johnson said it took him 9 days to stabilise blood glucose, another 9 days to reset his circadian rhythm and 18 days to recover normal sleep patterns. He also referred to research linking constant travel and jet lag with anxiety, depression, weakened immunity and memory-related brain changes, while suggesting people should limit international trips whenever possible.