>From that Wiki: "Their meals were composed of foods that were expected to typify the diets of people in Europe during the latter stages of the war: potatoes, rutabagas, turnips, bread and macaroni."
What an interesting study. Seems they had that limited selection of foods though so it's not just about the calories in that case. I've seen a few documentaries of people doing CRON (Calorie Restriction Optimal Nutrition) and they focus on very nutrient dense foods. I think mostly fruit and veg. Eat, Fast & Live Longer is the documentary I saw most recently. Luigi Fontana, M.D., Ph.D. talks about it and they visit someone doing the CRON diet and run tests. Doc said he was very healthy.
As I mentioned, Luigi Fontana is in the film and he's big on researching calorie restriction. Google shows he has been doing some studies on calorie restriction though I'm not sure which one to point you at, I haven't gotten to reading them yet since I just saw that documentary a few days ago.
I know know they've done a study with rats that's shown a link between CR and longevity though and I can at least point you at that. https://www.ncbi.nlm.nih.gov/pubmed/21792819
That said this is just something I've been reading about recently, still looking into the topic so I don't have any real opinion on it yet.
What an interesting study. Seems they had that limited selection of foods though so it's not just about the calories in that case. I've seen a few documentaries of people doing CRON (Calorie Restriction Optimal Nutrition) and they focus on very nutrient dense foods. I think mostly fruit and veg. Eat, Fast & Live Longer is the documentary I saw most recently. Luigi Fontana, M.D., Ph.D. talks about it and they visit someone doing the CRON diet and run tests. Doc said he was very healthy.
https://en.wikipedia.org/wiki/CRON-diet
http://optimal.org/voss/cron_overview.html