trouble assimilating conclusions of 9/19 research review

[Evanther]

The researchers only controlled for a tiny fraction of the participants total overall energy intake, and the difference in avg. PDCAAS score for each group was almost surely not different. Given that all subjects got their protein from a mix of animal products and plant products and all animal products are >.91, if the participants got ~1/2 of their protein from animal then it isn't likely that their avg. pdcaas would dip far below .75.

Calculating based on MFP for the past few weeks, it looks like I'm hovering around .71. Getting 1.8 kg/bw with >20% bodyfat, I'm not concerned at the moment, but I am contemplating the trade-off between dropping this to ~.6 in order to increase use of fiber/solid food generally and address burgeoning satiety concerns.

I know you probably don't think it makes sense to guess at a particular number when a below-avg pdcaas becomes a concern, but from what you're read on my situation is this change in strategy likely to be a mistake?

One more: do you think hemp protein is useless as a supp, or also from deshelled hemp seeds? I'm seeing a .66 PDCAAS on wikipedia for the latter...

[Jordan Feigenbaum]

Evanther,

For your question regarding the research review, I do not know what the average PDCAAs were in each group, as a full accounting of each individual's diet was not provided. The supplemental protein was ~ 1/3 of each individual's diet. You're right that this may not be a big enough difference to affect outcomes, but since there are other converging lines of data showing no real difference provided the protein doses are high enough, I'm not sure I'd worry about it.

To be clear, I wouldn't use a calculated PDCAAs to guide protein management or recommendations. Your current protein intake seems fine to me. I think hemp protein is not the greatest supplement with it's PDCAAs and EAA content compared to other vegan sources.

-Jordan

[Evanther]

Evanther,

For your question regarding the research review, I do not know what the average PDCAAs were in each group, as a full accounting of each individual's diet was not provided. The supplemental protein was ~ 1/3 of each individual's diet. You're right that this may not be a big enough difference to affect outcomes, but since there are other converging lines of data showing no real difference provided the protein doses are high enough, I'm not sure I'd worry about it.

To be clear, I wouldn't use a calculated PDCAAs to guide protein management or recommendations. Your current protein intake seems fine to me. I think hemp protein is not the greatest supplement with it's PDCAAs and EAA content compared to other vegan sources.

-Jordan

Thank you for your response, Jordan.

I just want to follow up by asking you to clarify the hemp comments. You say its a bad choice as a supplement, but as you know, supplements sometimes have different pdcaas scores then the whole foods version of the same source, e.g. soy. Do you mean to say that what you understand to be the pdcaas of de-shelled hemp seeds, ordinarily sold in a bag of small, soft seeds rather than the powder often associated with the term "supplement", are essentially valueless as a protein source?

If "yes":

House, James D.; Neufeld, Jason; Leson, Gero (2010-11-24). "Evaluating the quality of protein from hemp seed (Cannabis sativa L.) products through the use of the protein digestibility-corrected amino acid score method". Journal of Agricultural and Food Chemistry. 58 (22): 11801–11807. doi:10.1021/jf102636b. ISSN 1520-5118. PMID 20977230.

Could you explain what you see as the primary issue with the methodology and/or conclusions drawn from this? Or is there an abundance of more recent stuff I haven't seen that badly outweighs it?

[Jordan Feigenbaum]

I meant that the PDCAAs and EAA content of hemp is not as great as other vegan sources, which is what I said.

For example, the study you cited suggests the PDCAAs of hemp is:

The percentage protein digestibility and PDCAAS values were 84.1-86.2 and 49-53% for whole hemp seed, 90.8-97.5 and 46-51% for hemp seed meal, and 83.5-92.1 and 63-66% for dehulled hemp seed

The PDCAAs for soy and pea protein are both close to 100 and have higher concentrations of EAAs than hemp protein.

It also appears to cost significantly more, so I'm not sure why anyone would choose to use it over another source unless they had a bunch of it lying around. That said, if you want to use it to hit your total daily protein goals, I'm not sure that it matters.