#EVOOvsButter Trials and Tribulations

Although involving a lot of unpleasantness, the last three days have been interesting, to say the least. To explain why, we should start from the beginning…

Inspiration for the EVOOvsButter Experiment

Before this experiment, there have been a number of others that used a ketogenic meal replacement mix with different sources of fat. These were mainly carried out by Keto Chow owner, Chris Bair — often in collaboration with yours truly.

The most impactful one for me was when Chris performed a full six weeks swapping in and out various oils that were either predominantly saturated, monounsaturated, or polyunsaturated. (You can read up on it in full here). He had likewise followed up with some further experiments involving friends and family to provide additional data as well.

When doing our “Tandem Drop” experiment, Siobhan used exclusively Keto Chow shakes with heavy whipping cream throughout without issue. In fact, she was getting up to around 6,000 calories a day for the final stretch (note her maintenance calories are closer to 1,500!)

I mention all this because my considering the meal replacement shake with a refined fat source actually has a lot of precedent and appears safe enough, at least in the short term.

Extra Virgin Olive Oil vs Butter – First Attempt

I laid out the design for the original experiment here and got started Tuesday, June 30th, with the Extra Virgin Olive Oil (EVOO) phase. The first three and a half days went okay overall without any substantial symptoms, save some lethargy and and lower appetite (the last shake of each evening took me a while to finally finish off).

However, on the evening of the fourth day I seemed to be feeling a hightened sense of anxiety that I’d describe as comparable to what you get with nausea — but without the nausea. It was mild, but did increase my anxiety and made it difficult to sleep.

On the morning of the fifth day (4th of July), I had a collection of mild symptoms that included less energy, an odd sensation in my feet and calves, and further anxiety that seem to carry over from the night before. Given the leg problems, I was inclined to assume these may be electrolyte issues — something I’ve struggled with before while keto.

I decided to pause the experiment to retool with a stronger electrolyte base for the next version.

Extra Virgin Olive Oil vs Butter – Second Attempt

The revised version of this experiment began three days ago with a much stronger electrolyte regime. I also added in a direct source of protein through consumption of a lean burger patty with every shake. Another key change was a lower quantity of the fat source (i.e. EVOO at 12 tbsp/day vs the original 15)

While the initial Thursday went by without incident, I was feeling symptoms in the morning of the Friday after with both low energy and very mild nausea that appeared to dissipate after a couple hours.

My first scheduled exercise of the day is a 2.3 mile walk at around 7am, where I was especially rundown. Following this I typically do some maintenance strength training ad libitum (such as pushups) which I had no energy for and simply skipped.

For the first scheduled meal at 9am I found I had no appetite, something very unusual. I managed to slowly get through my burger patty but kept eyeing my EVOO shake suspiciously. I was getting more doubtful I could consume it without forcing it down and between this and the collection of symptoms, I reluctantly decided to pause the experiment — for a second time.

While I was optimistic this momentary second pause would snap me back into place, I was wrong. The nausea and lack of energy both increased marginally into the evening and I fell asleep for two hours from 6pm to 8pm on the couch. I then had trouble getting to sleep and kept moving in and out of a state of insomnia (also very unusual).

After getting up on Day 3 (yesterday), I realized I wasn’t anywhere close to normal. While the nausea was gone, my energy levels were even lower and I had no appetite until the afternoon. I felt like one does after having been sick for a while and was now coming out of it — being “on the mend” as it were.

Why So Different This Time?

Much of the reason I’m giving the full accounting of everything before this point is to emphasize the unusual nature of this last attempt. Sure, a clear common denominator is the EVOO and perhaps even the 1/3 dose on my coming revision is still too much, I don’t know yet. But I can’t help but wonder if there’s something different about this time compared to the last.

One thought that occurred to me is that it might have been a bad batch of EVOO. While all of them came from the same Kirkland bottles, the current shakes I made were from a newly opened one in the batch. Is it possible they could be different from one bottle to the next in a material way when consumed at scale?

The Next and Last Attempt

As mentioned above, I’m going to attempt to do this experiment one more time, but with 1/3rd the quantity for each intervention (just 4 tbsp / 57g). I’ll be filling the remaining calories with “neutral foods” that try to hit a 50/50 balance between SFA vs MUFA/PUFA.

I had hoped to be on track with that experiment right away, but clearly I should take a little more time to get re-centered first.

The Toll of Setbacks

One aspect to these ambitious n=1 experiments I don’t talk about is the mental preparation. Kind of like gearing up for a marathon-like competition, I’m spending weeks to months getting my headspace aligned for a long haul of a very structured days. It’s a lot of anticipation and planning depending on the scope of the project — and my experiments rarely get larger than this.

Thus, these kinds of developments that actually disrupt a 4-week planned initiative are very emotionally taxing, particularly given all the meetings, podcasts, etc that I schedule around them. Often my wife will plan meals and experiences for immediately following the completion of these experiments as she knows it can’t happen during, so this news is very disappointing to her as well. (Have I mentioned my wife is a saint for putting up with all this?)

Data is Data

While I have outlined a lot of negatives above, let’s not lose sight of the silver lining — even disappointing results can be valuable data in their own regard. I have some new hypotheses regarding what may have happened that may potentially show up in the coming bloodwork once I have this experiment back underway. But I’ll save those thoughts for a later time.

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1 month ago

Thanks for the interesting write-up.

While reading about your trials and travails, I found myself wondering about the olive oil. I’ve read that the olive oil industry has problems related to the purity and freshness of their products, even when the packaging says it contains 100% EVOO. Further, supposedly rancidity is often not noticed by the general public, unless the oil is extremely far gone.

Additionally, olive oil tends to be high in salicylates, which can bring a whole other level of problems, should a person find themselves beyond their personal threshold of being able to clear it from their system. Ask me how I know know…

Jak Mang
Jak Mang
1 month ago


I suffer from symptoms that are very similar to what you describe. The problems are hard to describe and I was impressed with your choice of words. I have been on a fairly normal keto diet for almost 4 years. I have been suspicious of electrolytes as I use a sauna daily. If you have time, I’d like to discuss details further offline.


Raphael Sirtoli
1 month ago

Hey Dave, most US olive oil is “stepped on”, so I wonder if Occam’s Razor is that you’re simply ingesting crazy amounts of OXLAMs and suffering the consequences. In Europe (Italy, France, Spain, Greece, Portugal) no person who’s serious about their olive oil would buy it in (a) a plastic bottle and (b) in a transparent container. They’d also store it a relatively cool room/cupboard. Maybe that sounds pretentious but I think there are good reason for it: it’s a very delicate oil due to the consequential PUFA content (~10% or more), terpenes and oleocanthal which gives you the back of the throat ‘pinch’ and is a potent anti-inflammatory.

I wouldn’t bother with a 3rd attempt until you can get olive oil that’s lab verified or with a meaningful certification (e.g. D.O.P if it’s from Italy). Freshness is *everything* with this product, meaning when the olives were harvested, not just the date on the bottle. I know, complicated…

Mike anderson
Mike anderson
1 month ago

Look at Cobram Estate in Australia

Eva Smagacz
Eva Smagacz
1 month ago

Raphael has a point: find someone who is traveling from Italy or Greece and get single source, first cold pressing oil, estate bottled and sealed.

30 days ago

I resonate with what has been shared about supermarket shelf olive oil. EVOO has been rife with shysters I believe. I buy mine from the farm gate, so I can trust when it has been pressed, how it has been pressed, how it has been stored, etc. It then goes in the fridge at home, but that’s me having an abundance of caution.

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