Learning your own diabetes

When not to change things yourself

The moments when adjusting your own setup is most tempting and least wise, and what watching well looks like instead.

Written by Updated 7 March 2025 6 min read
The 60-second answer

Some of the best diabetes decisions are the ones you do not make. A confusing number tempts you to start adjusting things, and sometimes the wisest move is to write it down, change nothing, and take it to the people whose job the change actually is.

  • Insulin settings, your basal (background insulin), ratios and correction plans, are set up with your diabetes team. Changing them is their call, made with you, not a solo experiment.
  • A single odd reading is nearly never a reason to change anything. One number is noise; a repeat over days is a pattern worth taking in.
  • Mid-illness, mid-stress or on a brand-new sensor is the worst time to redesign anything: the data underneath is temporarily strange.
  • Feeling frustrated with a number is a signal to pause, not to act. Changes made at 2am, or angry, tend to be the ones that cause the next problem.
  • Not changing things is not doing nothing. Watching, noting and reporting is the work that makes the eventual change the right one.
What it means for you

Why the urge to fiddle is so strong, and why it backfires

Type 1 hands you the controls, so when a number looks wrong the natural instinct is to reach for them. The trouble is that glucose answers to dozens of things at once, food, timing, activity, stress, sleep, hormones, the sensor itself, and a change made off the back of one strange day is a change made against noise. It often “works” by coincidence, then quietly causes a problem somewhere else in the day, and now two things have moved and you cannot tell which did what.

There is also a safety edge to this. Insulin is powerful, and the difference between a sensible tweak and a rough night can be small. That is exactly why the big levers, background insulin, ratios, correction plans, are worked out with a team who can see your whole picture, rather than adjusted solo on a bad evening.

None of this means you have no say. It means the strongest position you can be in is holding good information, not holding freshly moved dials.

The wrong moments

Times when changing things is most tempting and least wise

A few situations reliably produce strange numbers, and they are precisely the situations where changing settings misleads you. During illness, glucose often runs high and behaves oddly; that is the illness talking, and it passes. Your sick-day plan and your team cover that ground. During a stressful stretch or after terrible sleep, the same applies: the numbers are real, but the cause is temporary, and settings changed to fit a bad fortnight will not fit a normal one.

New kit muddies things too. A sensor on its first day can read oddly, and a new insulin, pump or routine needs time to show its true shape. Changing anything else while that settles means learning nothing from the change. And any decision reached in the middle of the night, or in a moment of frustration, deserves to be re-made in daylight before it becomes real.

The common thread: change teaches you something only when the ground underneath is steady. When the ground is moving, watch instead.

The strong move

What to do instead of adjusting

Watching well is an active skill. When something odd keeps happening, note when it happens, what was going on around it, and what your glucose did, for a week or two. Group readings by time of day rather than reacting to each one. That turns a vague feeling of “things are off” into something concrete: high most mornings, or dropping every football night, or fine except weekends.

Then take it in. A pattern with notes behind it is the fastest possible appointment: your team can see the shape immediately, ask the right questions and, where a change is genuinely needed, make it with you and explain the reasoning. You come away understanding your own diabetes better, which compounds. A solo tweak teaches you nothing you can trust; a worked-through change teaches you something you keep.

And if a number needs acting on right now, a low, or a high with ketones or feeling unwell, that is not “changing your settings”, that is following the plan you already have, and your team or 111 when unsure.

What varies

What shifts where the line sits

The line between “yours to handle” and “take it to the team” is not identical for everyone. Early on, almost everything belongs in the second pile. With years of experience, and agreements made with your team about what you manage day to day, more sits in the first. What never changes is the principle: the levers you move should be ones you and your team have agreed are yours, moved for reasons you could explain, not guesses made against a weird week.

how long you have had type 1what you and your team have agreedpens vs pumphow steady your routine iswhether you are mid-illness or mid-upheavalhow much data you have to hand
Real-life examples

Where holding still wins

Examples, not instructions or doses.

The single weird Tuesday

One afternoon spikes out of nowhere, no story, no repeat. You note it and move on. It never happens again, and the settings you did not change carry on working the rest of the month.

The flu fortnight

Two weeks of illness send everything strange. It is tempting to redesign your whole setup around it. You follow your sick-day plan instead, and once you are well the old normal comes back on its own.

The 2am temptation

A frustrating night has you ready to change several things at once. You write the plan down and sleep on it. In the morning, half of it looks unnecessary, and the other half becomes a good question for your team.

What to notice

Worth paying attention to

Whether an odd reading has repeated before you treat it as meaning anything
What was going on around a strange number, illness, stress, new kit, bad sleep, before blaming your settings
The pull to change several things at once, which leaves you unable to tell what did what
Decisions forming late at night or mid-frustration, which deserve to be re-made in daylight
Anything that needs action now rather than observation: a hypo (a low, below about 4 mmol/L), or a high with ketones or feeling unwell, which is plan-following territory, not settings territory
What to ask your team

Questions that make an appointment useful

"Which day-to-day decisions are mine to make, and which would you always want to be part of?"
"When a pattern shows up, how long should I watch it before we look at it together?"
"What is the quickest way to get something to you between appointments when I have spotted a pattern with notes?"
"Can we agree what counts as urgent enough to act on straight away versus watch and report?"
Sources