#486: Blood Glucose Spikes: How High is Too High? – Mario Kratz, PhD & Nicola Guess, PhD

In Podcasts by Danny Lennon4 Comments

Table of Contents

  1. Introduction
  2. Guest Information
  3. Related Resources
  4. Premium Content
    • Detailed Study Notes
    • Transcript


Peaks in blood glucose (or “blood sugar spikes”) are commonly highlighted as something harmful to health. And, of course, an excessively high blood glucose response to a meal can be problematic, or at least indicate there is a problem.

However, elevations in blood glucose after eating are a normal physiological response. And “bad” blood glucose responses are those that stay high for a prolonged period; i.e. after elevating, they don’t return to normal within an appropriate period of time.

But now many normoglycemic people are worrying about normal blood glucose responses, due to information that portrays even moderate elevations in blood glucose as harfmul. To add to the confusion, people are looking at standardized cut-off thresholds for diabetes and pre-diabetes, and mistakenly using them to label their own response to eating as measured by a continuous glucose monitoring (CGM) device.

When it comes to normoglycemic people, there is still a grey area in relation to how much of a glucose spike is a cause for concern. And given that there are still open questions that evidence has not fully answered yet, there is room for different interpretations of how to answer this question.

So what actually is a blood glucose peak that is “too high”? Is it 7.8 mmol/L (140 mg/dL)? 10.0 mmol/L (180 mg/dL)? 11.1 mmol/L (200 mg/dL)? Or do we even need to think about this once standard measures (e.g. HbA1C) are normal?

To discuss this interesting area, Dr. Mario Kratz and Dr. Nicola Guess are on the podcast to offer some perspectives and their conclusions from the current evidence base.

Blood Glucose Unit Conversions:

  • 1.7 mmol/L = 30 mg/dL
  • 7.0 mmol/L = 126 mg/dL
  • 7.8 mmol/L = 140 mg/dL
  • 9.0 mmol/L = 162 mg/dL
  • 10.0 mmol/L = 180 mg/dL
  • 11.0 mmol/L = 198 mg/dL
  • 11.1 mmol/L = 200 mg/dL

Guest Information

Mario Kratz, PhD

Dr. Mario Kratz is a clinical researcher in the areas of nutrition, obesity, and cardiometabolic disease, with more than 20 years of experience running clinical studies in a variety of populations.

He has previously been an Associate Professor at Fred Hutchinson Cancer Research Center (or Fred Hutch), as well as a faculty member in the Departments of Epidemiology and Medicine at the University of Washington. He still hold an appointment as an Affiliate Investigator at Fred Hutch, and continues to be involved in several clinical research projects. However, the majority of his time is currently spent creating content for his company, Nourished by Science.

Nicola Guess, PhD, RD

Dr. Nicola Guess is a dietitian and the research programme manager for type 2 diabetes remission at the University of Oxford. And she is currently a member of the National Institute for Health and Care Excellence (NICE) expert committee.

Dr. Guess was previously an assistant professor at King’s College London, and Head of Nutrition at the Dasman Diabetes Institute in Kuwait. She completed her clinical dietetic training at the University of Houston, and holds a Masters in Public Health from Florida International University and a PhD from Imperial College London.

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  1. Great podcast, thank you! I’ve been one of those believers that always low is best. I feel so much better now. However, my problem is more about going low BG after eating. My fasted BG is around 4.4-4.6 and after eating not uncommon for me to end up in the 3.8 range. I know this is as problematic as having high BG but not sure what to do to improve my situation. I eat 3-4 x a day and meals consist of a balanced load of macros. Would appreciate any advice you may have and thank you.

    1. Author

      Thanks so much Kim! Glad you found it useful.

      Unfortunately, I can’t give any clinical recommendations here. So this would be worth discussing privately with a dietitian. If you’d like to discuss with Dr. Guess specifically, you can find her details here: drnicolaguess.com

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