I can't see any negative short-term impact of pipe smoking on blood sugar levels..... insulin-dependent diabetic who tests at least 4-5 times a day. Likewise on blood pressure.... if nicotine is indeed a vasoconstrictor it hasn't seemed to raise my BP. If anything, my BP has improved as my cigar and pipe-smoking has increased
Now, today MDs are trained to parrot the no-smoking mantra and as it applies to cigarette smoking, their caution may be reasonable. What hard evidence I have seen concerning the health impact of pipe smoking (and I can't claim to have seen or understand it all) doesn't frighten me enough to get me to quit.
That's my personal judgment; at 73 the parameters are easier to calculate. What I might do at 43, before diabetes and hypertension set in would probably be different.