Originally Posted by
genejockey
My view is that sugar, starch - carbs generally - are fuel. Just fuel. If you're burning energy, you need fuel. If not, you don't. Fat is also fuel, but slower burning - though more energetic per gram. Important to remember that your brain only runs on glucose - part of why one feels so stupid when bonking.
True, except you can make your own carbs from fat and protein and the brain only requires something like 30% glucose in the energy mix after a few days of adaptation to carbohydrate restriction. Technically, therefore, you can live on very little carbohydrate, like Shackleton's men, who survived in good health for months on a steady diet of seals and birds and then had the energy to make an arduous ocean crossing in an open boat and trek over the snow-covered spine of an island.
Then, of course, a bunch of them died in WW1.
