This is a proposal based upon the Dempster-Shafer theory of imprecise probabilities. We cannot state for sure that a determined range of protein intake is the best for a determined subgroup, given the differences in opinions, even among the experts. So I tried to build a model based on the Dempster-Shafer frame, a theory which treats quantitatively imprecise or fuzzy numbers, providing as outputs ranges of probabilities and not deterministic numbers.
I used Elon’s GROK platform to develop the answer. These are the constraints or hypotheses.
-The model is valid for moderately active, healthy adults >60 years
-There are 3 possible scenarios. a) modest protein intake, 0.8 to 1.0 g/kg/d; 2) moderate to significant protein intake 1.0 to 1.6 g/kg/d; 3) Large or very large protein intake, that is > 1.6 g/kg/d.
I assigned a priori masses or beliefs of : modest intake = 0.1; moderate to significant = 0.45; large or very large 0.05.
The above based on the suggestions of luminars and also on the actionability of the suggestions. This resulted in the scenario of large amounts having the smalles belief, since if we eat so many proteins, without having serious issues of sarcopenia or without trining intensely, then we sacrifice fiber and other healthy foods for a disproportionate amount of protein, and this cannot be a reasonable proposition.
I’ll attach the brief report in .PDF produced, plus the final summary which has been tailored to those who do not know the mathematics behind the theory.
Please note: this is not by any means a final conclusion, on the other way I would like to encourage those who wish to propose different beliefs to do so, together with their reasonings, so that by iterative discussions we may revise the results. I saved the answers in a Grok project so it shoudl be easy to revise every details.
6. Simplified Results for Mathematically Lay People
Think of the results as confidence ranges instead of exact numbers.
- The classic RDA (0.8 g/kg/d) has only 10–45% support. It is possible but not strongly believed.
- The range 1.0–1.6 g/kg/d has 45–85% support. This is the most credible and widely accepted target.
- The very high range (>1.6 g/kg/d) has only 5–10% support. It is highly unlikely to be necessary for the average moderately active adult >60.
- There is 90–95% confidence that the optimal intake is at most 1.6 g/kg/d.
- There is 55–90% confidence that it is at least 1.0 g/kg/d (i.e., the old RDA is probably too low).
Practical recommendation: For most moderately active healthy adults over 60, aim for 1.0 to 1.6 grams of protein per kilogram of body weight per day. This range is strongly supported by current evidence and expert consensus. Intakes above 1.6 g/kg/d are not necessary for the average person in this group.
This DS model shows that the evidence is clear enough to give a confident practical recommendation, while still acknowledging some remaining uncertainty.
grok_report.pdf (3.5 MB)