Unfortunately it was not I who had the privilege to do this. These esters are still very new to the market and global distribution is not, plainly put, easily available.
I haven't been to the US since these esters have become available on the market, which is just a couple of months - at this moment. But since things move fast these days, I'm expecting they would become more available pretty soon.
The price is prohibitive for the most people, but I guess it could be affordable for many. Before we get into that...
There have been tons of products marketed to help increase ketone levels - like MCT and C8 oil or ketone salts (betahydroxybutyrate salts), but the level to which they achieve their purpose is modest.
I tested C8 oil which rapidly converts to ketones in the body and I got conflicting results: 15 ml of C8 oil raised my blood ketones with 0.5 mmol. However, we're talking about something different if we refer to ketone esters.
One of these is betahydroxybutyrate-1-3-butane-diol which when ingested acts like a 'cascading' effect. It not only delivers betahydroxybutyrate but butane-diol converts to more betahydroxybutyrate. So, the effect is enhanced.
KetoneAid, for example, has given many samples to people to test and post videos of their tests on Youtube. Most testers, upon ingesting the ester, have seen dramatic increase in the circulating ketones starting 15 minutes after.
A typical output would be going from 1mmol/L to 5 mmol/L. And that artificial ketone boost drives along multiple effects - probably most of them in terms of cognition and energy levels. I won't get into more details, but I'd recommend watching the tests by the people themselves. For one, I look very forward to get my hands on one of these esters soon.
Now, back to pricing, I say they may be prohibitive because they cost (currently) somewhere at $1 per 1ml. One typical serving in a test would be 40-60 ml. However, I guess you could achieve good results with as little as 15-20 ml.
You might consider they cost a lot, but compare that to $20k-30k price range it took to synthesize these esters just a few years back. In fact, this price seems very low. I look forward to see it getting lower, given the interest in ketone research (and the potential good effects in pathology, sports performance, and also, why not, wellness?
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Cristi Vlad Self-Experimenter and Author