Back in Japan after nearly 2 years in Singapore.
Before leaving, for the final 2 months, I went on a much stricter food regimen, where I stopped having many of the foods that have been so harmful to me throughout my life. Worst offenders have been sodas/sugar drinks, chips/crisps, fast food, table salt and coffee. Readers know that these changes have been very positive for me.
Whenever our routine breaks, whether due to business travel, relocation, significant life events (marriage, birth, death of a loved one) or uncommon stress (loss of job, relationship breakup, final exams) we are susceptible to revert back to old bad habits and lose our awareness as a coping mechanism. We revert to our self-destructive behaviors. For many smokers/drug users/alcoholics this is a recurring theme - it goes well day by day until some big event happens that disrupts the routine. Then it is back to square one.
I argue that it is better to establish healthy routines that are only rarely (hopefully never) disrupted, rather than the reverse, which is the case for most of us. Make your healthy lifestyle your usual baseline, and do your best to be extra vigilant during times of change to make sure good habits are not disrupted.
Make your good habits the hardest habits to break.