I read the wiki and it was just too complicated for me to get my head around. Best I could deduce was its kinda like an insulin shock. What I couldn’t figure out is at what point you’re at risk of it.
I’m currently doing rolling 48s, trying to shed some pounds, and I’ll typically have a large meal or go out to a restaurant at the end of my fast. Is this something I need to worry about or is it only a major risk with much longer fasts?
Refeding syndrome is a condition that is blown waaaaaaaaaaaaaay out of proportion. It is largely a problem among a starving population that is malnourished. Have you seen the pictures of the people rescued from concentration camps at the end of WWII? A bit over 4% of that population suffered from it.
If you do long fasts, 7+ days, you should dial in your electrolyte intake and certainly take it slow when it comes to reintroduce food into your system. If you rush it you may end up with diarrhea and all sorts of discomforts. This is not refeding syndrome, this is just your particular gut not liking the sudden change.
Something that shouldn’t even be mentioned for recreational fasting. Happens in extreme starvation situations and even then only occasionally. Sometimes an issue with people with long term severe anorexia. People like to equate having an upset stomach when reintroducing certain foods to refeeding syndrome but they are two wildly different things
You have a tightly regulated amount of minerals in the blood for you organ function. After a long enough time without food replenishing them, those levels are at a bare minimum to survive. A sudden spike in food causes insulin to take those last bits of minerals and shunt them out of the blood and into cells. Then your organs don’t receive them and can fail.
Refeeding syndrome is predominantly about having severely depleted phosphate levels, which are needed for carbohydrate metabolism. When you switch from burning fat stores during a fast, to burning the massive amount of carbs some people eat as their first meal, their body has serious drama occur, where phosphate gets pulled from all the others places it needs to be to allow metabolism, resulting in brain drama, gut drama, bone drama etc.
So avoidance of this is three part:
Most people eating a full and healthy diet achieve part one sufficiently well that parts 2 & 3 aren’t needed unless doing a massively long fast.
Potassium and magnesium levels can also be an issue, though as almost everyone supplements those during purposeful fasts those are super unlikely (more a situation for malnourished people who have been starved).