Are CRON diets dangerous? The case of Roy Walford

Roy Walford was an advocate of low-calorie eating. At one point, he and others spent many months inside of a BioDome, growing their own food. 

They found it difficult to grow enough food to provide optimal nutrients. So they ended up doing an unintended calorie-restricted diet which went on for many months. Dr. Valter Longo has speculated that extreme malnutrition Walford and others experienced inside of the BioDome may have been a factor in his developing Lou Gehrig’s Disease. 

This is certainly believable. But were Walford and the others following a typical CRON (“Calorie Restriction with Optimal Nutrition”) diet? Not at all.

The “diet” that Walford and others were forced to follow inside the BioDome was much lower in calories than than the usual CRON diet. (Some days, the participants ate only a few hundred calories a day, as food was in very short supply) (Most CRON diets have 1800+ calories a day.) It was also much lower in other nutrients, making it very different from a typical CRON diet, which is carefully chosen to optimize vitamins, minerals and other nutrients.

The BioDome experience was definitely stressful on the bodies of the participants. But people who follow the CRON diet are not typically “stuck” inside of BioDomes, eating less than optimal food. They have access to ample nutrients (they’re just eating lower calories).

And if it had actually “caused” Lou Gehrig’s disease to show up many years later in Walford –– what about all the other participants? Did the all develop Lou Gehrig’s disease? There is no record that I’m aware of that any of them ended up having similar health problems. But even if they had, it would not be a reflection on the CRON diet, for reasons outlined above.

Very low calorie diets like the CRON diet may or may promote health or longevity in humans. But the fact that Walford developed Lou Gehrig’s disease many years later, does not establish cause and effect.

-Nils Osmar


This article is not intended as medical advice.