Hi,
@CTS , a few tips and things to watch out for.
Gary Scheiner's book Think Like a Pancreas is worth a read. He's T1 and a endo so he's got both personal and professional experience of it.
One thing which we see quite commonly with newly dx'd is that they read every book on the subject, experiment with carb counting, think they've got it sussed, then it throws them a few fliers, and they start getting dispirited, and the reality that it's for life and doesn't play by the rules sinks in.
I'm not saying that will definitely happen with your man, but just that we've seen it happen so many times before with newly dx'd it's something to keep an eye open for, so maybe have a think in advance about how you might deal with that.
Counter-intuitively, telling them it will all be fine can sometimes make it worse. He might say, easy for you to say, you've not got it. I had a few arguments with my parents along those lines when I was dx'd at 21. One approach is to simply agree and say, yes, it is difficult.
If he goes through that sort of delayed shock, it is a stage, we all generally get past it and find a way of accepting it.
Carb counting is certainly worth learning. The simplicity of saying x units for y carbs is an attractive idea, but it can becomong frustrating when, as you've seen, you can get different results from the same meal on two different days.
The reality is that as soon as insulin is injected and food eaten, they are subject to a wide range of biological processes which can lead to different and unexpected outcomes depending on how those other factors play out.
There's also other things which he's maybe too early in the game to be aware of yet, but will pick up over time.
For example, before a meal, I'll think about how much carb, and how much insulin, as a starting point, but I'll also be thinking about how active I've been in the last few hour, how active I'm likely to be in the next few hours, whether I've got insulin on board from the last shot, whether I'm trending up or down, the type of food in terms of GI, and generally how responsive I've been to insulin in the last few days. All those factors will likely, to varying degrees, lead me to adjust both the amount of insulin and the timing of it.
It's also useful to think about the "shape" of insulin over time. It has a pattern. For example, novorapid is about 20 mins to start working, peaks at an hour or two, tails off after three to five hours. Carb counting isn't just figuring out how many units for x grams. It's also trying to match the pattern of the insulin to the pattern of the absorption of food over time. It's why many of us "pre-bolus", inject before a meal, to give time for the insulin to get to work before the food gets into play. That way, the insulin will already be in place and working by the time the food is digested and ends up as glucose in stream. If that's not done, the insulin can end up playing catch up. Wouldn't worry about this too much just now, but keep it in mind for the future. Different foods digest at different rates, and some just seem to fit some people's patterns than others, so it's worth experimenting with that sort of thing. For example, with me, white rice is a nightmare, but brown rice fits perfectly.
One approach which is gaining in popularity now that cgm like libre are becoming more available (including on script in some areas) is Stephen Ponder's Sugar Surfing.
You might think that with all the unmeasurable variables involved that it's an impossible task. Sugar Surfing accepts that it is unpredictable but then says that if you've got cgm, you can have a glance at the screen or your watch from time to time, and when you see it starting to go out of line, you can consider whether a small adjustment is needed, say 5g of glucose, a biscuit, or 1 or 2u of insulin, to nudge it back in line before going too far out of range.
Sure, it requires a bit more attention, and perhaps a few more injections, but I've found it to be time well spent, because I'd much rather spend a few seconds fixing a small rise or fall without any drama instead of the time and hassle of sorting a major high or low.
If the docs haven't already mentioned cgm or libre, do ask about it. We're having to deal with a constantly moving and unpredictable target, so it's only fair that we get to see it. With strips alone, we often just get to see the aftermath of a high or low after they've happened, whereas cgm let's us steer things in advance to avoid them.