rule of fours

Factual Questions
1

“A human being can go four minutes without oxygen without suffering permanent damage, four days without water without suffering permanent damage, and four weeks without food without suffering permanent damage.”

Several people have told me this over the years, inlcuding a medical student, and I’ve even seen it in print in various non-medical places. Is this true? It sounds like bamboozle to me; it’s just a little too cut and dried. But my GP waffled when I asked him this. It may be there is no standard answer. And what exactly constitutes ‘permanent damage’, anyway? Death? That’s pretty permanent. But I suspect the above-quoted is simply referring to some unspecified illness or disability brought on by this type of deprivation. I know brain damage can occur when oxygen is denied, but what about the 4 days/no water adage? Kidney problems? Heart problems? Or the 4 weeks/no food part- what happens then? I’ve treated animals on the brink of starvation before - malnourishment and starvation have to be treated carefully or death may actually ensue because of the cure.

I’m wondering if this true, and if it’s not, where this came from. Thanks.

2

4 days without fluid intake is pushing it beyond the safe limit; quite a few people will die if they do that and I would say that counts as ‘permanent damage’

3

It’s more of a mnnemonic than an absolute rule and serves to remind you of the relative importance of oxygen air and food.

For what it’s worth, I seem to recall that brain damage can begin after two minutes without air.

4

It’s a glurge plain and simple.

5

I used to hear it as the rule of threes. 'Course, I can hold my breath for three minutes, sometimes, no special preparations.

It depends on a lot of different factors.