Hi Paul,
I completely agree, and I too have done a study in Kenya showing no increase in fat mass acretion vs lean mass when treated with RUTF vs RUSF. That was after a few weeks.
Thompson's study looked at NCD risk in survivors after after several decades.
I think its a luxury to be able to consider optimising treatment for the health of the individual several decades down the line; we need to prioritise immediate survival, healthy growth and development. And you're right to point on that the insult of SAM, and greater severity of SAM maybe be worse than the rapid weight gain. We havent been able to unpick that yet. Especially since those with the fastest weight gain tend to be those who were most wasted to begin with - a major confounder in the analyses.
But, if we COULD acheive early treatment, survival, healthy growth and development, on a slightly slower weight gain so that there is lower risk of later life NCDs, that might be the best of all worlds! Still lots more work to be done on this topic though.
Tash