UBC study reveals cheat day during Keto diet may cause some harm

(Ian Collings) #1

UBC is a well known and respected university in BC Canada. I was wondering if anyone had seen this study and had any comments. I have not been able to find the original paper yet to study it in more detail.

Its not clear to me what baseline testing was done to establish inflammation markers prior to the test, i.e. did the bio-markers rebound to normal pre-keto levels, or did they bounce higher than the same markers associated with a SAD ?

New study. Maybe not a good idea to indulge now and then in non-keto foods
(Alec) #2

In a similar vein, the problem here is the apparent lack of control group not doing keto. The real comparison required here is what happens to whatever markers they are studying in keto cheaters vs non-keto folks eating exactly the same food as the cheaters during the cheat day.

It is really dumb to say: “you’ve made yourself healthier, but if you cheat you will not be as healthy”. Well, duh!! The question is: if you do keto, then you cheat, are you less healthy than if you had not started keto? I can’t see any evidence for that.


Here’s what I think is the actual study they didn’t link in the article. Same authors, appropriate title.

Reading now…

I’m going to stick this one in the same topic since it deals with essentially the same phenomena, Peripheral Insulin Resistance (PIR) a.k.a. glucose sparing, from the perspective of a T1D.

One of his points is about PIR. Some of the other points, not so legit.

Not only could Drew no longer eat a healthy snack like a banana without a large blood sugar spike, but he noticed that he needed more and more insulin, “To bring my blood sugar back down into the normal range.”


PIR is a real and known phenomena of the keto diet. If someone has been keto for a while and they take an oral glucose tolerance test (OGTT), they can show up as bordeline T1D. A two week period of carb loading is recommended before testing so response returns to normal.

But the question is, does a cheat day let you keep your glucose tolerance? I guess not if the same thing happens every week?

[And is it inherently harmful?]

(Carl Keller) #5


“What we found instead were biomarkers in the blood suggesting that vessel walls were being damaged by the sudden spike in glucose.”

If you are doing this twice a year, does that make it worse than doing it every day when you are on the SAD? Common sense suggests we should avoid foods that cause inflammation, period.

I could rewrite this article from a different perspective and title it:

Study proves LCHF removes inflammation and improves coronary health


OK, I’m not getting that from the actual study. Here’s some takeaway quotes:

These findings indicate that dietary modulation can influence AMPK activation in circulating immune cells, and that inducing relative glucose intolerance in lean healthy young males through short-term HFD appears to reduce, and not increase, inflammatory MAPKs activation in PBMCs following glucose ingestion.

However, contrary to our hypotheses, the greater rise in blood glucose following glucose ingestion after the HFD (i.e. relative glucose intolerance) led to blunted MAPKs signalling. Activation of MAPKs and inflammatory pathways in PBMCs following acute glucose ingestion has previously been shown to be higher in obese individuals with glucose intolerance compared to lean counterparts [19,20]. Our findings indicate that these previous findings may not be related to exaggerated hyperglycemia per se, but may be related to underlying pathologies associated with obesity and/or insulin resistance.

Didn’t they find exactly the opposite?? I’m confused here, because I don’t have a solid grasp of the inflammatory pathways involved. What I’m reading says ‘yes, PIR happens’ but ‘no it doesn’t cause inflammatory response in healthy men.’

Actual data:


“We were originally looking for things like an inflammatory response or reduced tolerance to blood glucose,” Durrer said. “What we found instead were biomarkers in the blood suggesting that vessel walls were being damaged by the sudden spike in glucose.”

And which markers are those?

(Carl Keller) #7

My statement is a hyperbolic example of spinning data to suit a predetermined goal, although I believe the statement is generally correct. :slight_smile:


Yes, I was talking about a disconnect between the article and the study. They found no inflammatory marker increase yet insist that markers for blood vessel damage are elevated. I’m not seeing what they’re talking about. :thinking:

… it has something to do with PBMC’s, about which I know nothing!

Peripheral blood mononuclear cells (PBMCs) are known to respond to systematic changes in nutrient availability.

(Scott) #9

My first glance was 9 people on a high fat low crab diet for 7 days. I don’t think that would represent people that are long term keto WOE.


Yes, they admitted that long-term dieters would “need further study”. :joy:

But, if anecdotal experience counts, the longer you’re keto the more likely you are to have an increased response to a glucose challenge.


So, this is the blood vessel damage marker they’re studying:

Following the HFD, there was a significant reduction in phosphorylated AMPK assessed in PBMCs in the fasted state. Two hours after glucose ingestion therewas a further decrease in the phosphorylation status of AMPK post- HFD compared to pre-HFD


Which is a very complicated thing. LINK If reduced phosphorylated AMPK is such a bad thing, why do we see it in the fasted state of post-HFD? Is there something else going on here that doesn’t line up with the author’s assumptions about changes in phosphorylated AMPK?

(Paul H) #12

Ok OK… no more cheating… My bad.

(Karen) #13

It seems if you want to cheat that it would be better to just cycle between carnivore, and keto.

(Ken) #14

I’d be interested to see the duration of the study. Having carb days or meals in the early phase of adaptation is not a good idea, especially if hyperinsulemia is still present. I somehow doubt they followed subjects long enough to determine effects once derangement is eliminated.

New study. Maybe not a good idea to indulge now and then in non-keto foods

Maybe the findings may be different if the participants were fat-adapted.


Thanks for your input

New study. Maybe not a good idea to indulge now and then in non-keto foods
(Bunny) #17

UBC study reveals cheat day in popular diet may cause some harm

Updated: March 28, 2019 12:58 am

”…But according to new research from UBC Okanagan researchers, just one 75-gram dose of glucose — the equivalent a large bottle of soda or a plate of fries — while on a high fat, low carbohydrate diet can lead to damaged blood vessels.

On the keto diet? Ditch the cheat day

March 27, 2019

”…The researchers point out that with only nine individuals included in the study, more work is needed to verify their findings, but that the results should give those on a keto diet pause when considering a cheat day.

Journal Reference:

  1. Cody Durrer, Nia Lewis, Zhongxiao Wan, Philip Ainslie, Nathan Jenkins, Jonathan Little. Short-Term Low-Carbohydrate High-Fat Diet in Healthy Young Males Renders the Endothelium Susceptible to Hyperglycemia-Induced Damage, An Exploratory Analysis . Nutrients , 2019; 11 (3): 489 DOI: 10.3390/nu11030489

”…In conclusion, one week of low-carbohydrate high-fat feeding that leads to a relative impairment in glucose homeostasis in healthy young adults may predispose the endothelium to hyperglycemia-induced damage. …” …More

One week? Really? :thinking: NOT KETO!