Sulfur in cysteine and methionine


Stoinov – I think this is spot-on. What matters is the SAA intake, and that should be more than covered if you’re consuming an adequate supply of complete proteins. Supplementation in any forms should not be necessary.


MSM is not included in official Soylent. Your calculations are apt in showing that with adequate protein with a complete amino acid profile, the two sulfur amino acids should provide plenty. When I was starting out I must have either not been getting enough protein, or the joint pain was caused by something else. This is the danger of a sample size of 1.

At this point we are confident that MSM is not essential given enough cysteine and methionine and we have removed it from Soylent. You should also feel confident removing MSM from your DIY blend. In fact, I recommend it, for reasons mentioned above.


Yay. No more deathly smelling farts.


That might be a value add for the gradeschool versions, @cheapskate88 :stuck_out_tongue:


It’s a value add for everyone in a relationship. Or in public.


I have found the amount of SAA in soy protein isolate to be at 2.6g per 100g of protein. That is from 1.3g each of methionine and cysteine.

I had a hard time finding a source for the info, but finally took it from here:

I would appreciate any feedback if anyone has a better source for the information, or if you see any error.


I get the same. My source is the label on the package.


Thanks for confirming. Unless I am just blindly missing it, it is not on my label.


Mine itemizes the amino acids. I think this could be different from product to product, though.
Alanine 4.1
Arginine 7.6
Aspartic Acid 11.6
Cystine 1.3
Glutamic Acid 19.6
Glycine 4.1
Histidine 2.7
Isoleucine 4.5
Leucin 7.7
Lysine 6.1
Methionine 1.3
Phenylalanine 5.3
Proline 5.4
Serine 5.1
Threonine 3.8
Tryptophan 1.4
Tyrosine 3.7
Valine 4.6


this website breaks down SAA’s in certain proteins pretty well, its not exhaustive, but it helps.


I looked over this again, and realize a possible problem. Rob noted In this post that after 3 months on his soylent, using whey isolate/concentrate blend, he started noticing symptoms of sulfur deficiency, which he fixed by supplementing with MSM sulfur powder. Why would he end up with sulfur deficiency if whey protein has a considerable amount of sulfur in it?


This was his best guess. It doesn’t necessarily mean he was correct in attributing the cause to a sulfur deficiency.


I would also be curious how our bodies use the sulfur in protein.

I know that our digestive system essentially breaks down proteins into their constituent amino acids, and our body reconstructs the proteins we need (which is why certain proteins are essential: we cannot build certain amino acids ourselves).

Do we repurpose the sulfur in the proteins during this process? Or is the sulfur specifically for building new proteins? I know joint issues are a symptom of sulfur deficiency, but is this because our joints need elemental sulfur or the proteins we can build with it?


He didn’t have sulfur deficiency.

@Rob has since said that he was mistaken and was not actually experiencing sulfur deficiency. I don’t recall that he clarified what the true problem turned out to be though, or maybe it’s that he never found out the actual cause of his symptoms. I believe he also addressed the mistake during the fireside chat a while back.

Sufficient amounts of complete protein will provide sufficient SAA’s. MSM is not needed.


I suck at math, so please explain this in layman’s terms: how should I calculate say, 1 g of methionine, and 1 g of cystine? Does that mean 1 g of cystine is 0.27 g of sulfur, and 1 g of methionine is 0.21 g sulfur?


That is correct. Just to restate the conclusion of this ancient discussion, you don’t need to worry about sulfur if you’re getting your protein.


Yeah I’m aware of that, I just needed to make sure that I’m calculating the protein from the SAA accurately… I use hemp seeds a lot anyway, and hemp seeds are rich in the sulfur amino acids. I don’t use MSM myself (never have), but I thought I might as well exclude it from my new recipe that I’m working on.


Yeah, that horse has been fairly beat to death, I suppose ^_^.

Sounds tasty. Good luck!


I’m sure it has, lol. But that doesn’t make any sense. If my calculations are correct, with the exception of egg protein, the average figure of meth+cyst per 100 g protein, is typically in the range of 2-4 g, but to get 2 g of sulfur per day, you’d need around 8 g of meth+cyst. I calculated an average of meth+cyst x 0.24, which means yóu’ll need 8.33 g of meth+cyst to reach 2 g sulfur. This means you’ll have to keep your protein intake at 300 g or more, if your protein source is soy. Anything else I’m missing here from the equation?

Seems to me it’s just cheaper to go with MSM.