Acclimating to vanillin or sucralose?

Perusing the discussion that’s been had so far on headaches with soylent, it seems fairly common for people to get headaches when they’re starting out. Many people have said their headaches went away within a week or so. Different theories have been floated about the headaches, including increased potassium intake, sodium withdrawal, caffeine withdrawal, dehydration, and sensitivity to vanillin or sucralose.

I’m on Day 4 with Soylent but I’ve only been doing one glass a day so far, not 100%. My caffeine intake has not changed, and I have been accompanying my soylent with salt to avoid any sodium issue. But I am getting headaches, and those headaches only start up while I’m drinking Soylent. Yesterday I skipped my Soylent – didn’t have something else, just skipped the meal – and had no headache. The fact that the headaches coincide with consuming Soylent suggests to me that sucralose or vanillin is likely the culprit.

Can anyone who experienced headaches with Soylent – similar to mine in that they were directly triggered by drinking the Soylent and seem to be a reaction to something in it – tell me if those headaches went away over time? Clearly some people had headaches that went away, but if those people were getting headaches based on sodium/potassium/dehydration issues, it doesn’t help me. I need to figure out if headaches resulting from sucralose or vanillin will go away, whether as a result of my body getting acclimated somehow or otherwise. If not, there doesn’t seem to be a point in continuing to subject myself to the pain.

Anyone with a similar headache experience stick with it for a while and find their headaches did/didn’t go away?

Edit: Sorry, should have specified the version. I’m doing 1.5.

1.5 doesn’t have vanillin and only 15mg of sucralose. The people suggesting adding salt did so back during early Soylent versions that didn’t provide the RDA for sodium, but now it does so that’s probably not the problem either. I have no idea what’s up, sorry :smiley:

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Unless you’re drinking 1.0-1.3, there is no vanillin in Soylent currently. It was removed from 1.4 and 1.5 (but might return in 2.0). Also note that the amount of sucralose in Soylent 1.4 is only 30 mg per pouch and that was further reduced to 15 mg per pouch in 1.5. So that’s a whopping 3.75 mg per 500 calorie serving of 1.5. You can easily test your hypothesis by drinking a soda sweetened with sucralose; they apparently contain about 27-60 mg per 12 ounce can. Similarly, there are dozens or hundreds of “normal” food products flavored with vanillin you could try, if you are drinking an old version. You can also buy vanillin and sucralose powders off eBay to test more directly.

As far as headaches triggered by sucralose, I found this: Migraine Triggered by Sucralose—A Case Report. I’m not going to pay for the full paper, but the subject was a single individual. I don’t know if the single-blind exposure (vs. sugar) was in a coated pill or something she could taste, but if it was the latter the results mean nothing because sugar and sucralose have distinct flavors (to me anyway).

There is also this: Popular Sweetner Sucralose as a Migraine Trigger, but it has no information without spending money, so not much I can say there.

Neither means anything if you don’t suffer from migraines.

Personally, I only suffered from headaches with 1.0 and 1.3 when I failed to add table salt to them. I eventually realized after starting 1.4 that either the added sodium or my body had adjusted to the point that I didn’t need to add table salt anymore. I think 1.5 slightly decreased sodium but I haven’t had any headaches on it.

Caveat: I had been supplementing potassium for at least a year prior to trying Soylent 1.0, so I was already hitting or exceeding the amount contained in Soylent in my “normal” diet. I’ve also usually been at 1000-1500 calories of Soylent a day, rarely hitting 100% Soylent except to see if I could.

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Hello, I had Soylent induced headache too. Mine are triggered from tension in my neck, which are likely a muscle spasm in the small neck muscles. I ruled out dehydration early on, and my only guesses were either a specific mineral or vitamin being the culprit.
It could be a sodium/potassium balance or something similar to niacin flush* (a B vitamin)… But it is odd it can be triggered from a single serving of Soylent.

Right now I am not really using my 1.4, but I may give it another shot soon.

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Which version are you on and how much salt are you adding? Add as much salt as the taste allows (as long as the total intake is below 2300 mg sodium you should be fine. That is if you are not hypertensive or fully sedentary/obese.) Headaches could also be due to the high potassium in soylent than we are used to in conventional food and increasing salt could balance it out in theory. Along with testing with a soda, try this and see and keep us posted :smile:


Thanks – I’m doing 1.5. Once I’ve got enough of a break in my work schedule that it’s safe to experiment with potential headache-inducers, I’ll experiment with another source of sucralose and report back.


I’m on 1.5. In fairness, the amount of salt I added the first two times was pretty small; I did a couple shots of pickle brine with extra salt in them the second time, but it wasn’t until after the headache had flared up badly. Today I started to drink my Soylent and had a bunch of salt and brine handy to take with it, but I got gun-shy when I started to feel a bit of head fog shortly after starting to drink – I had a work deadline and couldn’t afford to be dealing with a headache – so I called it off and had regular food instead. I’ll try upping the salt mixed-in/up-front.

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I have always had problems with any drinks sweetened with Sucralose. It gives me a subtle, but very distinct mental fog. I can’t describe it very well but it only happens if I have Sucralose.

With Soylent 2.0 it’s tolerable because of the low amount they put in it, but I have to spread out my Soylent intake or the effect begins to accumulate and really bothers me. Luckily I wasn’t planning on giving up food entirely but it’s still disappointing.

I’ve put my subscription on pause for now.

I sent a complaint and they replied saying “it’s only 15 mg and it masks the flavor of the vitamins/minerals” but that’s not good enough to keep me subscribed. I’d suggest looking into Tagatose because it’s much sweeter than Isomaltulose, also slow digesting, and it promotes low blood sugar. With that or some mix of Tagatose + Isomaltulose you could probably get the neutral flavor without any Sucralose.

FWIW, I didn’t want to bump this old thread by the time I got back up to speed with my Soylent consumption, but I took the advice in this thread and added more salt (about 1/4 tsp per 500 cals of Soylent 1.5) and did not have any further headaches. I also bought a little bottle of sucralose off ebay, but by the time I had an opportunity to test it the salt solution had already worked for me – so I never tried it out. Perhaps I still will one of these days.

Interestingly, though, I have not added any salt since switching to 2.0 – which, as far as I can tell, has no more sodium in it than 1.5 did – and have had no fogginess or headaches with it. I am also not aware of 2.0 having any less sucralose in it than 1.5 did. So whether my issue was sodium, potassium, sucralose, or something else, my body has apparently adjusted to the Soylent formula. Hooray.