Silly questions

Im new to insulin and have some silly questions I forgot to ask my GP if anyone can set me straight.

  1. Is it possible to drop your fasting bg levels 100 pts with basal alone or would I need a bolus regime as well?

  2. If 1u of insulin drops bg a certain amount ie. 50mg/dL what does 10u of basal do over 24 hours? Why does it just keep it steady?

  3. Why can’t someone just eat something wait and see what happens to their levels and then take rapid acting (correction) to bring it down? Why do you try and predict what it will do, dose and then go low or high depending on how right you were? Is there such a thing as a “correction” regime?

  4. I’ve never had a hypo as far as I know. why would that be? The highest I’ve been ever is 288. Lowest was 86 and I didn’t feel that bad (obviously because it’s not that low). What is the science behind why all of a sudden taking insulin means ill suddenly have bad lows?


It’s not only possible but practical. But do it gradually and incrementally until you reach the equilibrium you seek. And bolus insulin isn’t for controlling fasting BG. Its job is to prevent (or, failing that, to knock down) transient spikes, regardless of whether caused by food or something else. Don’t confuse the roles of basal and bolus insulin. They are distinct and separate tools for distinct and separate jobs.

People do that all the time. It’s not the ideal course, however, because it’s reactive (after the fact) rather than proactive (preventive). Which relates directly to the next question–

Because the goal is to stay as close to the normal range as possible for as much of the time as possible. The technical term for this is “time in range” and you want to maximize it to the greatest practical degree. The less time you spend with abnormally high BG, the better the odds for long term health.[quote=“PemW, post:1, topic:58288”]
The highest I’ve been ever is 288. Lowest was 86 and I didn’t feel that bad (obviously because it’s not that low). What is the science behind why all of a sudden taking insulin means ill suddenly have bad lows?
Lows happen because you took too much insulin or too little food. The “science” is to match the two as closely as possible. The better the match, the less excursion, either high or low. With time, study, and experience, you will get very good at keeping the two in proper alignment. But there are so many variables affecting carbohydrate metabolism that perfection isn’t really achievable. There will be times when extraneous factors such as illness, stress, or whatever will cause you to go higher or lower than you planned to. The idea is to keep the frequency and the degree of those excursions very low, and with practice you will.

By the way, a fasting BG of 86 is not low at all in the big picture. It’s smack in the middle of the normal range for the average nondiabetic, nonpregnant, nonobese person.

There are some truly excellent books available to help you master this. Two of the best ones are listed below.

Gary Scheiner, Think Like A Pancreas (Boston: Da Capo Press, 2011)

Richard K. Bernstein, Dr. Bernstein’s Diabetes Solution, 4th. ed. (New York: Little, Brown and Company, 2011)


I’m embarrassed to say I’m reading both of those now. Of course I haven’t had my endo appt yet so I’m jumping the gun. I want to know what I’m talking about when I meet her (I’ve got a bit of reading to do- this site is amazing). Tight control would be great but ultimately it would mean mistakes which is pretty terrifying. Would I chicken out and have high readings for a short period (using a wait and see corrective approach)? I’m sort of leaning this way already.

It has now been six years since I’ve started insulin. I have been fortunate to never have had a serious low. Using insulin doesn’t mean you must suffer lows. Several things have helped me. I eat a low carb diet which means that I use much smaller doses of insulin for meals. I also learned to fine tune my insulin myself, adjust the levels to proper settings. And most recently I obtained a CGM which is highly protective as it alerts me to the possibility of an impending low and I can treat it before I even go low.

ps. A basal insulin alone may cause a low but it will be a long and slow low which will give you hours to see it coming and do something about it.


Using insulin is an imperfect solution for a life threatening problem. Imperfect as it is it is the solution that works the best. For a T1 diabetic its the only one that works There is risk involved, that’s part of what makes the solution imperfect. Balancing the risk involved is an important part of the game. Being too aggressive with insulin can lead to unwanted lows but playing it too safe by maintaining higher BG levels creates an increased future risk of complications.

How do we manage the risk, we educate ourselves, learn from our mistakes and not shy away from them. The answer is not to give up but to learn to make better decisions.

I applaud you for being proactive. both are excellent books. I suggest you use what you learn to supplement what your doctor says, not to contradict him or her.


The reason not to wait to see what happens is that insulin correction takes a long time - up to 4-5 hours, although most of it happens in the first 2-2.5 hours. So if say, 1.5-2 hours to see where your meal will take you, then wait for the corrective action of insulin, it will take you possible 2h wait + 2 hours correction = 4 hours out of range, during which you will be high.

Most T1Ds will pre-dose a meal by 15-20 minutes, sometimes longer (up to 40 some minutes) so that they peak as little as possible after their meal. If my son pre-does before lunch, he may only go up 10-20 (if he is lucky). If he does not predose but injects at the same time, he will go up to 150-180 before coming back down. If he waits 2 hours he will go to 250-300 and be too high for a long time.

Most T1Ds aim to stay “in range” for as long as possible every day. Depending upon your situation, in-range may be anything from 80-150 to 65-120. For my son, right now, in-range is 85-140, but we hope to bring this down to 85-130 soon. The narrower your range, the harder it is. And the lower your range, the more prone to hypoglycemia (glucose low) you are. So it is an issue of balance:-)

I think you are so right to read books right away. FYI, Bernstein’s book describes a specific school of diabetes treatment that focuses on low carb. It can be very successful, but some people have a very hard time following his diet. Many diabetics are successful using more moderate carb approaches. I don’t mean in any way to discourage you from using his approach! You should not feel, however, that it is the only way to success, and that you are doomed to failure if you can’t follow his system.

Within a few days of using insulin, you will be able to figure out general ratios that work for you. If I were in your shoes knowing what I know today, I would not use wait-and-see because you will be high a lot, and because you might have to stay up a lot of the night trying to correct your highs (it takes a long time). Instead:

  • to start with I would be on the conservative side in doing my corrections
  • I would dose right when I eat to start with (or anticipate by 15 minutes unless I am low)
  • I would be ready to experiment more during the day than for dinner
  • I would take early dinners with moderate carbs only, early enough to leave time to make corrections without having to stay up too long. For us, we try to have dinner before 7pm, although we fail often. It would be ideal if we could make my son eat at 5:30pm, unrealistic unfortunately.

But diabetes is a highly personal thing. Everyone reacts in different ways and works his/her own process - so making your own decisions is the right thing for you!

I’ll mention one last thing: in the long term, the most difficult thing I find is the amount of sleep you lose by having to be up to correct highs or lows (lows, obvisouly, are more dangerous in the short term). It’s exhausting when you have a bad stretch. So doing all you can to minimize night time risks is, imho, one of the most important things to do.

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Not having tight control and running high a good deal of the time is an infinitely larger mistake.


This is good advice. I eat dinner early 5pm so that’s handy. The overnight thing worries me the most until I get a cgm. I’ve been high for a long time so maybe I think nothing of being high for a few hours and I really need to change that mindset.

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Good point. I want her to think I’m capable of handling rapid acting and capable of titrating my own doses but I’ll definitely be in listening mode. :stuck_out_tongue_winking_eye:

I’d like to track my adventures with insulin, sort of like a daily blog is it okay to start a thread here or is there a better place I could do this ?

I’d recommend starting your own blog as opposed to a thread on TuD.

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Quite so. Bernstein’s approach is too strict for some people, but don’t let that stop you from mining his book for all the good info that’s in it. The book is full of highly useful information, both for general background (what is diabetes and how does it work?) and specific methods and techinques (dosing and timing, determining ratios, etc.).

The right way to approach any expert is to take what you can use and leave the rest.

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It’s hard to work out what’s happening with my Lantus. Only on day two. Pre-bed I was 252 (later than normal dinner), predawn 180, pre breakfast 200, two hours post breakfast 270, an hour later 180 :flushed: And still dropping. I predict I’ll be 153 prelunch. Based on this pattern if it continues for a couple more days I’d be tempted to raise my Lantus by 2u & see how that goes.

When basal testing is it better to do it during the day and discount dawn effect? I seem to rise between predawn-time I get up. If I delay eating I tend to keep rising anyway. I’m a bit confused by big/ fast drop after breakfast.

Are you also taking bolus insulin? Do you realize that basal insulin is not designed to continue lowering your BG, but rather to maintain your fasting BG (once you get it to a “normal” number)? If your Lantus actually lowers your BG overnight and continues gradually lowering it throughout the day, that is a sign that your basal dose is too high. Are you trying to use Lantus without a bolus insulin? That makes no sense… If you routinely see BGs over 100, why aren’t you correcting these with a bolus insulin?

Basal insulin is meant to metabolize the glucose output of the liver, nothing more, nothing less. Basal insulin comprises about half, roughly, of your total daily insulin needs. Thorough basal testing will individually test each segment of the 24-hour day. That involves missing meals, so the overnight test is the easiest to start with since most people don’t eat during the night. A successful basal dose will leave your BGs level (within a 30 mg/dL band) when a meal is missed or overnight.

The overnight basal test will involve calibrating the MDI basal dose to counteract dawn effect, if any. I have a pronounced need for an elevated insulin basal profile from 3 a.m. through mid morning. I have a hard time covering my dawn phenomena needs with a single MDI dose and then not also driving my late afternoons too low. A pump works best for me, but I enjoyed good success with Tresiba basal insulin when doing MDI. I’ve never used Lantus.

No bolus as yet. Basal only 10u at 8pm. I’ve managed to capture early morning drops (which are still around 162 for me) around 3am then a predawn rise but usually I’d be totally unaware of it. I usually wake with 180-200 which I still am even with basal on board.

I’m confused as heck. A fast drop from post breakfast to prelunch of 250 to 150 is weird implying basal is too high as you said.

I’ll know more when my libre arrives and I can track a full night. If it wasn’t for dawn phen. then I don’t think I’m as steady as I thought overnight and I definitely drop a lot after breakfast. I may have to stay on the 10u until my endo appt. but that means running high for two more weeks.

Why do you think this is weird? Once again, and as many people have already stated, basal insulin should not be lowering your BG per se. It should be maintaining your BG as it is designed to do with bolus insulin. IMO, it would be a waste of time to test your basal dose without first getting your numbers more in range throughout the 24 hours in a day with a MDI regimen (basal plus bolus insulin). Please read Think Like a Pancreas by Gary Scheiner. According to Gary, your basal dose is right when you wake up with the same BG (+ or - 15) that you went to bed with. In other words, your basal dose is correct if you go to bed (at least 4 hours after eating) with a BG of 250 and wake up with a BG of 235 to 265. Or if you go to bed with a BG of 100 and wake up with a BG of 85 to 115. If your basal insulin is lowering your BG by more than about 15, the dose is too high.


Lol, I’m going back to read that book again. I’m having trouble understanding how basal is meant to lower your fasting number but it’s not meant to lower blood glucose just keep it steady. That seems illogical to my brain.

It seems logical to me that I would bolus at night, get my bedtime number to a decent range then use basal to keep it there. How am I meant to get that bedtime number down using basal alone ?

My point exactly. Which why it is pointless trying to manage your diabetes with basal insulin alone.

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