A very interesting article, I have personal experience with:
> Coffee also affects the gastrointestinal tract. It increases stomach acidity and stimulates the release of hormones that aid digestion. Both caffeinated and decaffeinated coffee promote the contractility of ileal and colonic smooth muscle, helping prevent constipation
As the two times in my adult life I've tried to make an intended break from coffee, it has ended up with almost unbearable stomach pain caused by constipation.
It's good to know that this is not linked to caffeine as I thought, so I will try un-caffinated coffee instead now because I tend to think that my general "tiredness" comes from actual caffeine.
That fraction is going to depend a lot on the definition and the reference. I believe the 97% is the US standard for how much of the natural caffeine in green beans must be removed. You will note how this can be manipulated by using a more caffeine-abundant variety. EU standards are more sensible, stated in terms of caffeine content in the final product.
Either way, commercial decaf processes and normal brewing methods will yield something like 5-10mg of caffeine in a "decaf" dose of coffee, which is an order of magnitude less than usual.
> Coffee also affects the gastrointestinal tract. It increases stomach acidity and stimulates the release of hormones that aid digestion. Both caffeinated and decaffeinated coffee promote the contractility of ileal and colonic smooth muscle, helping prevent constipation
As the two times in my adult life I've tried to make an intended break from coffee, it has ended up with almost unbearable stomach pain caused by constipation.
It's good to know that this is not linked to caffeine as I thought, so I will try un-caffinated coffee instead now because I tend to think that my general "tiredness" comes from actual caffeine.