I have a confession… I like coffee.
I like coffee in the morning.
I like coffee in the afternoon.
I like coffee black. I like it white.
I like it with sugar, with chocolate, or just plain.
I like the taste of coffee.
I like the way it makes me feel and helps me stay focused.
getting more out of my coffee
Do you know how I could enjoy coffee more?
I could stop drinking so darn much of it, that’s how.
If I drank less coffee I would restore my sensitivity to it.
It would then give me more of a hit when I did occasionally have it.
getting less out of my insulin
In a similar way that many of us have become addicted to coffee that leaves us less sensitive to the impact of caffeine, many of us have also become addicted to cheap processed simple carbohydrates that leave us insensitive to insulin. We become more sensitive to carbohydrate and insulin if we have less of it.
the physiological insulin resistance straw man argument
One of the criticisms that is levelled at low carbohydrate diets is that it causes what is called ‘physiological insulin resistance’.
This can mean that a person who is restricting carbohydrates may end up with higher fasting blood sugars and may have higher blood sugars after a higher carbohydrate meal.
Check out this video to see how some interpret ‘physiological insulin resistance’ to be a bad thing and a reason to eat lots of carbohydrates.
diabetes diagnosis criteria
- HbA1c, which is a measure of your average glucose over the past three months,
- random blood sugar,
- fasting blood sugar, and
- oral glucose test.
what is physiological insulin resistance?
One of the clearest explanations of physiological insulin resistance I’ve seen comes from Paul Jaminet who says that physiological insulin resistance is a protective response of the body that ensures that the brain gets the benefit of a limited supply of glucose.
Because the rest of the body is refusing to take up glucose, and the liver takes it up slowly, a meal of carbohydrates is followed by higher blood glucose levels in someone on a low carbohydrate diet.
The human body is very adaptive to different situations and different fuel sources. Just because our reference data is from the past few decades when we have typically eaten large amounts of processed carbohydrates, we take that as the new normal.
Is physiological insulin resistance such a bad thing?
Maybe, maybe not.
Let’s look at what this means when it comes to the various tests that are done to diagnose diabetes.
oral glucose tolerance test
Yes, you may fail an oral glucose test if you are on a low carbohydrate diet due to physiological insulin resistance. But this guy will probably see a rise in his blood sugars too if you fed him the equivalent of two cans of Coke in one hit. 
If you have a large dose of fast digesting carbohydrates your body is not primed to dump a pile of insulin into the system. It takes a while to wind up and adjust to large amount of carbohydrates. You also don’t have a high level of insulin washing around in your system from the last pizza meal.
It’s sort of like me and my coffee addiction. Because there is not a lot of time when I don’t have some caffeine in my system I am not as sensitive to caffeine as I would be if I only had an occasional cup.
If you do want to pass an OGTT all you have to do is increase your carbohydrates for a few days before the test and your pancreas will increase the amount of insulin in your system and be better prepared for a high dose of carbohydrates. 
fasting blood sugar
Some people may find that their fasting blood sugars rise a little when they start consuming more fat and decrease carbohydrates, particularly if they increase their fat intake.
This is an area where your mileage may vary. I have seen some people run at very low carbohydrate levels and end up with progressively higher fasting blood sugars. Others see their fasting blood sugars continue to come down and ketones go up as they decrease the insulin load of their diet.
When on a lower carbohydrate diet you won’t have high levels of insulin floating around in your system and your body may choose to run blood glucose levels a little bit higher by secreting more glucose from the liver. This is not really a problem if you feel OK.
Many people find this to be a passing phase and after a time of keeping the insulin load of their diet low see their blood sugars come down.
As you keep the glucose load of your diet low you will ‘dry up the root’ and eventually after glucose stores in the liver are depleted, your fatty liver is resolved and your body fat levels are reduced you just won’t have as much glucose available for your liver to keep pumping into your bloodstream.
If you find that you don’t feel good at very low carbohydrate levels then by all means increase your carbohydrates and protein particularly to ensure that you are getting adequate nutrition. Check out the Goldilocks glucose zone article for more thoughts on how to find the right level of glucose for you.
Most people find that their calorie intake decreases with a LCHF approach, however as this study from Dr Thomas Syfriend shows long term excess calories even with a high fat diet is probably not going to end well. Intermittent fasting or tracking your calories to make sure you’re not overdoing the butter may be helpful if you’re not achieving normal fasting blood sugars.
random blood sugar
Carbohydrates are the most potent thing that raises blood sugar. If you are on a low carbohydrate diet chances are your random blood sugar (i.e. non-fasting) will be much lower than if you were on a high carbohydrate diet.
With a smaller amount of dietary carbohydrates you should see much lower post meal blood sugars.
Generally the small amount of insulin that you generate after meals will bring your blood sugar down quickly.
With lower post meal blood sugars your average blood sugar will likely be much lower on a low carbohydrate diet. Therefore your HbA1c, which is a measure of your average blood sugar over three months,  should be lower.
We are now understanding more and more that insulin resistance is public health enemy number one. Insulin resistance is a better predictor of heart disease than HDL, LDL, BMI and smoking! 
Making sure you have some time when high levels of insulin are not floating around in your bloodstream will help increase your insulin sensitivity and enable your body to manage your blood sugars.
Consistently high levels of carbohydrates will ensure that your insulin resistance stays high!
I am probably not going to stop drinking coffee any time soon, but in view of the evidence I do try to make sure that I have periods where I give my body a chance to restore its sensitivity to insulin!