So... While we're discussing potency and tolerance... I have a question.
Is there truth in the belief that partaking of different strains reduces tolerance? I've tried it and it seems to work somewhat like a tolerance break, which is also supposed to reduce tolerance.
The short answer is "no."
The long answer:
Tolerance is built through repeated use. The more often that your body encounters a molecule, the more efficient it becomes at metabolizing that molecule. (Within reason of course, don't try to build your tolerance to cyanide, or Tide pods! lol) While different strains of marijuana have many differences, they all have far more in common than they are different.
Delta-9 THC is the intoxicating cannabinoid that we are all obtaining through our preferred method of ingestion. Except it's really not. And I will go in depth here, so things are going to get scientific. But first of all, there are a couple of things that you may or may not know that I will point out as I go. I'm not trying to be pedantic, just informative.
The first this is that the human body makes its own cannabinoids. They are used as neurotransmitters both in the brain, and throughout the endocrine system. This means that a very large portion of your body's cells have their own cannabinoid receptors. This is why marijuana has both benefits, and effects on so many systems that it appears to be a magic cure-all for everything.
Now Delta-9 THC has a carboxyl group that would normally prevent it from being able to bind with your body's cannabinoid receptors. Whether you choose to de-carb the molecule in an oven via slow roast, or with your lighter, that carboxyl group has got to go, or no high for you! Once you get the Delta-9 THC into your blood stream, it must be hydroxylized into 11-Hydroxy-Delta 9-THC, and this is the actual molecule that has an intoxifying effect. It is carried mostly by the red blood cells, but some of it is free floating in the plasma.
When smoking weed, there is a 53 second time frame until the plasma is saturated with with Delta-9 THC, and it takes between 3-10 minutes for all of the body's cannabinoid receptors to become bound with 11-Hydroxy-Delta 9-THC. When consuming edibles it can take a few hours for the same thing to happen, depending on numerous factors including dosage, how full the GI tract is, overall health of the individual, and numerous other factors.
While the 11-Hydroxy-Delta 9-THC is used by the cannabinoid receptors, it is changed to 11-nor-9-carboxy-Delta 9-THC, and released back to the blood stream. When the 11-nor-9-carboxy-Delta 9-THC next makes its way to the liver it is then broken down into glucuronide as a final waste product. 80% of which is passed through the feces, and 20% in the urine.
Studies (peer reviewed) have shown that for a daily user, 23-27% of the 11-Hydroxy-Delta 9-THC that is produced becomes psychoactively available. While the rest is matabolized by the cannabinoid receptors throughout the rest of the body. Casual and first time users can get up to 33% because their bodies aren't as used to dealing with the 11-Hydroxy-Delta 9-THC.
When smoked, the mean time for all of that metabolism to occur is 4.5 hours. With edibles it can easily double that time frame, if not go longer.
If you personally are wondering why you don't seem to have the tolerance that you used to, as a nurse for over 30 years, I would say that it is most likely due to your age. You have said that you are over 70, and as one ages, the metabolic process simply slows down. Not to mention that you said that you mostly consume through edibles and tinctures. Edibles provide more THC into the blood stream because while the THC has that original carboxyl group, it is highly vulnerable to heat destruction. That is something that simply "is" and no amount of internet complaining can overcome it. So, as your metabolism slows down, if you continue to dose yourself the same, it will allow the 11-Hydroxy-Delta 9-THC to build up in your bloodstream. On top of that, whatever medications your doctor has prescribed for you can severely affect your metabolic rates further exacerbating any perceived changes in tolerance.
If it's an issue, changing the strength of the tincture, or how often you take it could easily make the problem go away. If it's not an issue, then just enjoy the extra high. Almost all of the aging process sucks ass, so this could be a blessing in disguise!!!