Coffee is a staple of the American diet, and its popularity is on the rise among other countries as well. Many people believe that it gives them energy and vitality. It is also known as one of the most popular and delicious beverages in the world, which makes it a popular choice among consumers. But what are the effects of coffee on the body? The health benefits of coffee have been on the rise, and the less-known side effects are causing some concern among its consumers. In this article, we will discuss the potential health benefits and risks of coffee.

Coffee has been a staple source of caffeine for centuries, but you may be drinking more than you realize. Coffee beans contain caffeine, but the coffee you drink typically has an additional 40-60% more caffeine than the beans themselves. Caffeine is found in teas, herbal teas, soft drinks, energy drinks, and more. The actual amount of caffeine in a cup of coffee is highly debated, but most agree that a cup of coffee has anywhere from 80 mg to 200 mg of caffeine.

If you’re a regular coffee drinker, you know that a cup of joe can make your heart race and your palms sweat. In fact, drinking too much coffee may actually increase your risk for Type 2 diabetes, according to recent research. But, are coffee drinkers truly at risk for diabetes? Well, the jury is still out.. Read more about does caffeine raise blood sugar and let us know what you think.

Using a continuous glucose meter, I began an experiment last month to better understand how various meals and lifestyles influence blood sugar.

I’ve been researching whether or not drinking coffee increases my blood sugar for the last several weeks.

Although coffee does not contain sugar, some people believe it may have an impact, as our first encounter with coffee demonstrated.

Since then, I’ve had the same incident twice more. This is what I discovered.

Making plans for a coffee adventure

I devised the following experiment: I drank a cup of coffee and measured my blood sugar levels two hours before and thereafter. Then I looked at the statistics to determine whether coffee causes blood sugar to rise.

To improve the experiment’s dependability, I focused on four factors:

1. I’d have black coffee with no added sugar. 2. I would not eat or drink anything else for two hours before or after consuming coffee, and I would not stress or exercise during that time. 3. I’d try the ketogenic diet. 4. I went to sleep and awoke at the same time every day.

It was time for some coffee.

Coffee is being consumed.

The home was silent, but I was awake and anticipating having to do yet another experiment. The beans, the scales, the grinder, and the coffee machine were all ready. The glucose sensor was implanted in my body permanently and continuously monitored any changes in my blood sugar levels.


I placed 18 grams of coffee beans in the grinder using the household scale I described previously (about the same amount as for a double espresso). I switched it on. It looked like an elephant had been set free in the kitchen! Grrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr

The sound faded away after 20 seconds. I breathed from a can of coffee beans that I held to my nose. What a lovely fragrance!

With 2 dl of boiling water, I put the coffee into a Bialetti coffee machine. The coffee was ready in a few minutes. I took a sip right away. Oh, it’s difficult!

Because I didn’t add cream to the coffee, it didn’t taste as good as it usually does. Cremuccino, which is coffee with steamed cream, is my favorite coffee, but I couldn’t have it this morning since it would have ruined the experience. Nonetheless, the coffee was excellent, and it was gone in a matter of minutes.

I was continuously monitoring my blood sugar using an app, and I was on the lookout for even the tiniest fluctuation. Oooh, that’s intriguing!

Coffee does not seem to raise blood sugar levels.

The figures below illustrate my blood glucose levels after four hours for three separate tests. The blue line shows my blood sugar level when I drank my coffee that morning. A morning without coffee correlates to the red line.


Coffee may raise blood sugar levels, according to the first trial. But just a smidgeon:


As can be seen from the graph above, coffee does not cause my blood sugar to decrease to the same level as if I did not consume coffee in the morning.

This is my second try.

The second trial revealed that coffee had no effect on my blood sugar levels. My blood sugar levels were different on both days, but we don’t believe the coffee affected my blood sugar levels in the same way that not drinking coffee did (control).


Make three attempts.

The third trial likewise indicates that coffee does not significantly increase my blood sugar. My blood sugar levels are quite constant in the mornings when I’ve had coffee and the mornings when I haven’t, suggesting that coffee hasn’t had much of an effect on my blood sugar levels.



The average blood glucose levels of the three studies are shown in the graph below.


This indicates to me that coffee consumption does not substantially raise blood sugar levels.

However, the graph also indicates that when I consume coffee in the morning, my blood sugar is somewhat higher than when I don’t.

This difference, however, is not substantial and may be related to random blood sugar variations (for example, the morning rise in blood sugar when I drink coffee, even if I haven’t had coffee yet).

Ketone levels in the blood did not alter much.

In the second and third tests, the graph below shows the average ketones in the blood in the morning when I drank coffee (unfortunately, I didn’t detect ketones in the first experiment).


This graph also demonstrates that coffee does not increase blood sugar levels in our opinion.

When coffee increases blood sugar levels substantially, insulin levels are anticipated to rise as well, resulting in a reduction in ketone bodies. After drinking coffee, however, there was no discernible decrease in ketone levels.

When you consume coffee, what happens to your blood sugar?

Note to self: This is a n=1 self-experiment, therefore the results may not be applicable to you. I am 36 years old, a man who is insulin sensitive, weighs 69 kg, exercises for 10-15 minutes five times a week, and has no prior history of obesity or diabetes.

If coffee doesn’t increase my blood sugar, it’s unlikely to do so for you.

When you consume coffee, what happens to your blood sugar? Let us know about it in the comments section below.

How to Perform a Test

Do the following to see what happens to your blood sugar after you drink coffee:

1. Fast for two hours without eating or drinking anything. 2. Check your blood sugar level; this is your starting point. 3. Have a cup of coffee with no added sugar (no sugar, no sweeteners, no milk, no cream, etc.) For the following two hours, don’t eat or drink anything, and stay away from activity and stress (which can affect blood sugar). 4. After consuming coffee, test your blood glucose every 30 minutes for two hours (five times total, including a baseline test). 5. Assess your outcomes. Is there a substantial rise or fall in blood glucose levels?

* Even if you don’t eat, your blood sugar levels will vary throughout the day. Small variations, such as a 0.5 mmol/L (10 mg/dL) rise or reduction, are therefore a random fluctuation and not the consequence of coffee intake.

What should we look into right now?

Sugar alcohols, more artificial sweeteners, hunger, alcohol, and resistant starches were among the recommendations for further tests. What more do we have to put to the test?

Thank you for your ideas on how to make these experiences better. We will test ketones in addition to blood glucose if you want it. However, for studies that have been performed but not yet published, there may not be enough data on ketones.

The job of measuring insulin levels is more difficult. Is there a simple and reliable method to measure this many times each hour? Let us know about it in the comments section below.

Attempts made previously

Are you curious about the results of our past tests? Take a look at this episode:

  1. What’s keeping you from being in ketosis?
  2. In ketosis, how much protein can I consume?
  3. What you can eat while you’re in ketosis
  4. Do artificial sweeteners have an impact on blood sugar levels?
  5. Is it true that coffee raises blood sugar levels? preliminary findings

Ugh, don’t we all get enough of these articles? Does coffee raise blood sugar? Is low carb the best diet for losing weight? Is a diet that says everything in moderation works for everyone? Do protein bars work for weight loss? Can we eat too many eggs? But, do you ever wonder if coffee, in the end, really does raise your blood sugar? After all, as a frequent coffee consumer, you would think you know this answer by now.. Read more about does decaf coffee raise blood sugar and let us know what you think.

Related Tags

This article broadly covered the following related topics:

  • does coffee raise blood sugar type 1
  • does coffee raise blood sugar
  • does coffee raise blood sugar in diabetics
  • does coffee affect blood sugar test
  • caffeine blood sugar crash