Diabetes Self-Management Blog

Doctors have long known that thoughts and beliefs can have an impact on actual physical outcomes. This is one reason most research studies give a placebo (inactive pill or preparation) to study participants who don’t receive the drug or treatment being tested — simply knowing that they might be receiving treatment tends to improve patients’ conditions. And in the realm of diabetes, it is well established that mental stress and anxiety can have an impact on blood glucose control.

But can expectations about your blood glucose level actually have an impact on it? One Diabetes Flashpoints reader wondered about this and sent us an e-mail. Here is what Rosie P., who is 72 years old and has Type 2 diabetes, wrote:

I have had diabetes for about 10 years now, and it seems to me that perhaps diabetes involves psychological effects. After eating a low-carb or small meal that I think will result in a relatively low blood sugar reading, contrary to my thoughts, I find that I have a high reading! It also works in the other direction: When I do eat a larger portion of food, I think that my blood sugar will be high, but as usual it is the opposite of my thinking. So I am baffled… Perhaps there are some of you out there having the same conflicting thoughts and results?

What do you think? Could Rosie’s expectations of low or high blood sugar levels actually cause the opposite to occur? Or should she look for another explanation for her readings? Have you noticed anything like this? Leave a comment below!


  1. Yes, I have had the same surprise of opposite readings. Sometimes it is the food and sometimes the amount. I haven’t figured it out.


    Posted by Suzanne |
  2. Yes, I have also noticed that the readings are higher after eating a perfect portion and when I eat larger meals then the Blood Glucose is less and in target. I wander why and what should I do about it. Also have a question, Does the # matter after 2 hrs of meal if it is not in target??? I have found that if my readings are higher after eating in about 2 hrs and then when I re-test it again after 1 hr and it is very much control so I want to know if the # is higer after 2 hrs of meal does it damages during that time span or what?? please explain..


    Posted by mehaki |
  3. Yes this has happened to me. When I think my level would be low its high, and when I think it will be high its just the opposite. Strange….

    Posted by fosterm |
  4. I have had this situation occur also, but upon further investigation, I determined that the cause was NOT my expectation. For instance, I eat a piece of pizza expecting my blood sugar to rise, but when I check at around 2 hours after eating, I find that my blood sugar is “normal.” What’s going on? Well, when I check at 3.4 to 4 hours after eating, I find my blood sugar has gone up. Why? The fats associated with the pizza delayed the carbohydrates thus my blood sugar didn’t rise until much later. On the other hand, I eat a small salad w/ tsp of dressing, cup of vegetable soup and a small apple and think my blood sugar will be fine. No, it’s up. Why? I ate this lunch as part of a meeting which was very stressful for me plus I was inactive for over 2 hours during this meeting. The lesson I learned is that multiple factors affect my blood sugar level so I need to see the “big picture” rather than focus on one aspect such as food or expectations.

    Posted by AnnieG |
  5. I believe the comment posted by AnnieG has some truth to it. I was diagnosed 18 mos. ago and am having some problems getting my sugar levels on target. I am very active on our farm and with my business, and I am also an author, working on my second book. I believe that stress has a lot to do with the readings. I have a son that is disabled from an injury, that left him paralyzed, and I lost my 41 yr. old sister, from an enlarged heart, this past June, and the diabetes alone is a stressor. I have the same thoughts about the ups and downs of the readings after meals, but I just fight constantly with high readings and maybe the stress of that fact alone is hindering my health. Any advice on stress control?

    Posted by TracieH |
  6. I have had the same response. When I analyze the food I ate and the insulin I took, it usually ends up that I ate more fat or protein than I had thought and my glucose is higher for longer. Sometimes my glucose is lower and then I realize that I took too much insulin and perhaps didn’t count the carbs, fiber, fat, or protein correctly. It is very difficult to account for everything in every bite and sometimes I get discouraged. But, tomorrow is another day.

    Posted by Becky |
  7. I’ve often had unexpected readings. But for me the amount of exercise has a stronger effect than diet. If I get two one-hour brisk walks every day for a week, my glucose level is good even if my diet isn’t perfect.

    Posted by Stephen |

Post a Comment

Note: All comments are moderated and there may be a delay in the publication of your comment. Please be on-topic and appropriate. Do not disclose personal information. Be respectful of other posters. Only post information that is correct and true to your knowledge. When referencing information that is not based on personal experience, please provide links to your sources. All commenters are considered to be nonmedical professionals unless explicitly stated otherwise. Promotion of your own or someone else's business or competing site is not allowed: Sharing links to sites that are relevant to the topic at hand is permitted, but advertising is not. Once submitted, comments cannot be modified or deleted by their authors. Comments that don't follow the guidelines above may be deleted without warning. Such actions are at the sole discretion of DiabetesSelfManagement.com. Comments are moderated Monday through Friday by the editors of DiabetesSelfManagement.com. The moderators are employees of Madavor Media, LLC., and do not report any conflicts of interest. A privacy policy setting forth our policies regarding the collection, use, and disclosure of certain information relating to you and your use of this Web site can be found here. For more information, please read our Terms and Conditions.

Potatoes: Good or Bad? (10/20/14)
Sandwich Trouble (10/15/14)
Soda Surrender? (10/08/14)
Marketing to Kids (10/01/14)



Disclaimer of Medical Advice: You understand that the blog posts and comments to such blog posts (whether posted by us, our agents or bloggers, or by users) do not constitute medical advice or recommendation of any kind, and you should not rely on any information contained in such posts or comments to replace consultations with your qualified health care professionals to meet your individual needs. The opinions and other information contained in the blog posts and comments do not reflect the opinions or positions of the Site Proprietor.

Blood Glucose Self-Monitoring — Part 3: Smart Monitoring

10 Keys to Long-Term Weight Loss

Take Your Best Shot: Stay Up to Date on Vaccines

Complete table of contents
Subscription questions