I disagree with Terry mainly because the entire basal vs. bolus debate is contrived by medicine, but is completely arbitrary based on a few samples of patients in tightly-controlled clinical trials without having large ranges of diverse age groups, ethnicities, stresses in their lives, etc. – but its not how things work in reality. The 50-50 “rule” is complete BS and is meant to be a guideline only, IMHO.
I am a type 1 adult male, and even when I was pumping (I returned to multiple daily injections for a variety of reasons unrelated to this), more than 95% of my total daily dose is bolus only, with less than 5% being basal. In essence, if I don’t eat, I don’t need insulin to keep things steady but after 32 years with type 1, I also happen to have a fairly high C-Peptide indicating that I still make some of my own insulin, but there are many people do not and therefore require more basal insulin. Women, in particular, are much more likely to need a higher basal because of the presence of certain hormones in the body which can interfere with insulin’s ability to bind to the cell receptors.
Remember, in normal physiology, there is no such thing as basal vs. bolus – insulin is automatically secreted whenever its needed regardless of what causes the need. The notion of basal/bolus does not provide plasma glucose regulated insulin replacement or secretion as functional pancreatic beta cells do. However, you should not be concerned about the percentage of your total daily dose (TDD) which is basal or bolus, just as long as your TDD is not comparatively higher on a per kg of weight basis (unless of course you are sick or having other health issues, which will temporarily change your need for insulin).