Will This Knock Me Out of Ketosis?

Earlier this week I heard someone ask in a low-carb Facebook group if eating a particular food would ‘knock them out of ketosis‘ and I decided it was time to write an article about this, but first I ran a short poll on Twitter to find out what my readers thought.

The first answer in the poll was my tongue-in-cheek reaction to hearing the question asked for the umpteenth time and the other three options were reasonable answers that people could choose from.

Twitter poll: “Will this knock me out of ketosis?”

So what’s the answer?

According to Dr. Stephen Phinney, MD, PhD. Professor of Medicine Emeritus at the University of California, Davis who has over 25 years of clinical experience studying multi-disciplinary weight management programs, including the use of a ketogenic diet;

“Carbohydrate tolerance varies among individuals.  Some people may need to limit themselves to no more than 30 grams of total carbohydrates per day to remain in nutritional ketosis and maintain its benefits; while others may be able to consume more.  However, most people with underlying metabolic issues find that they need to maintain a carbohydrate intake below 50 grams per day, especially if they have Type 2 Diabetes.”

For the most part, men who are insulin sensitive and seeking to follow a ketogenic diet can do very well on 50-100 g of carbohydrate per day and women who are insulin sensitive who want to follow a ketogenic diet can do well on 50-75 g of carbohydrates per day. As Dr. Phinney points out, those with metabolic issues such as Type 2 Diabetes will usually need to keep their carbohydrate intake less than 50 g per day.

People with epilepsy or seizure disorder or who have been prescribed a ketogenic diet as an adjunct treatment to chemotherapy for specific types of cancer will need to follow a very strict high-fat ketogenic diet and the level of carbohydrate restriction is specific for those conditions.  For those who are insulin sensitive who are simply seeking weight loss, a low carbohydrate diet is often sufficient. I’ve found over the last several years of designing low carbohydrate diets for my clients that insulin-sensitive individuals often do very well simply cutting the total amount of carbohydrate down significantly and altering the types of carbohydrate they eat. For those with pre-Diabetes and Type 2 Diabetes, the types and amounts of carbohydrates they eat can be individually determined by testing glycemic responses to specific foods and I help my clients do this and understand the results.

What is the difference between someone who is insulin sensitive and someone who is insulin resistance?

People who have Type 2 Diabetes or pre-diabetes or Metabolic Syndrome are by definition insulin resistant but for those without these conditions, how would someone know?  There are two blood tests that can be done together (fasting blood sugar and fasting insulin) that can help estimate the degree of insulin resistance but there are visual cues that can also help.

insulin sensitive (from Klöting N, Fasshauer M, Dietrich A et al, Insulin-sensitive obesity, Am J Physiol Endocrinol Metab 299: E506–E515, 2010, pg. 5)

People who store most of their fat as subcutaneous fat, rather than visceral fat (fat in their abdomen) are often insulin-sensitive — even those that are very obese. These are people whose fat is mostly the type that hangs loosely over their belt and jiggles when they walk or laugh. Surprisingly, these are not the people that necessarily have metabolic issues, provided they also don’t have significant amounts of visceral fat (where it can’t be pinched and where it wraps the organs, resulting in metabolic disruption).

insulin resistant (from Klöting N, Fasshauer M, Dietrich A et al, Insulin-sensitive obesity, Am J Physiol Endocrinol Metab 299: E506–E515, 2010, pg. 5)

Those who store most of their fat inside their abdomen as visceral fat rather are often insulin resistant and as a result may have high blood pressure, abnormal cholesterol (lipids) or been diagnosed as having either pre-Diabetes or Type 2 Diabetes.

In order to reverse the symptoms of these chronic diseases, people with insulin resistance often need to maintain their intake of carbohydrate at a lower level than those who are insulin sensitive.

As far as the question as to whether eating a particular food will “knock someone out of ketosis“, if that food contains more grams of carbohydrate than their daily limit then yes, they will temporarily burn glucose instead of producing ketones from burning fat.

That said, for a low-carbohydrate lifestyle to be sustainable long term for the average individual without metabolic issues seeking weight loss, I don’t understand why some are focused on how many ketones they are producing.  This is not one of those cases that ‘more is better’. The body is very good at not wasting energy, be it as glucose or ketones so if people have been in ketosis for a considerable length of time, their body will often stabilize and produce a lower level of ketones, so as not to produce more than is needed. A lower level is just fine.

If you have been prescribed a low carb or ketogenic diet for a specific health condition or are taking one of the medications that puts you at risk of developing ketoacidosis (a potentially life-threatening condition which is very different than ketosis!) then yes, tracking ketones is important, but for the average person, eating the foods are on your Meal Plan will enable you to enjoy your meals while keeping to the amount of carbohydrate that your body tolerates, without counting anything!

That’s the beauty of this style of eating! There’s no need to weigh and measure food, so why become focused on carbohydrate counting or on ketone measuring?

If it’s a special occasion and you want to have a piece of something that is not normally part of what you eat then decide if eating a small serving fits your own health and nutrition goals.  If it does, have a small piece and enjoy it. If it doesn’t than choose not to.

Overall, if you focus on eating real, whole foods including plenty of healthy animal protein, low carbohydrate vegetables and leafy greens with just enough fat to make it tasty, then relax, eat and enjoy!

If you would like to know more about what’s involved in me designing a Meal Plan for you, then please send me a note using the “Contact Me” form above and for information on the various in-person or distance consultation services I provide, please click on the “Services” tab.

To our good health!


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Virta Health Blog, Dr. Stephen Phinney, https://blog.virtahealth.com/how-many-carbs-ketogenic-diet/

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