How much weight could you lose if you starved yourself for 40 days?

Answer 1

This question has several answers:

You would lose all of it because if you starved yourself completely, taking no food or liquid, you would be dead before the 40 days had expired.

Another approach is to look at your daily calorie intake. A commonly recommended intake to maintain health is 2000 calories per day. Carbohydrates and proteins provide 4 calories per gram and fats provide 9 calories per gram. Eating 222 gms of butter or 500 gms of steak a day would be equivalent to 2000 calories. Theoretically, if your diet had consisted entirely of butter and you ate nothing for 40 days you'd lose 8.8 kg; if it had consisted entirely of steak you'd lose 20 kg. So the amount you would lose depends on your diet beforehand.

There is a significant difference between 'starving' and 'fasting' - we usually think of starving as being something imposed on us by circumstances beyond our control, whereas fasting is undertaken voluntarily usually for purposes of physical or spiritual cleansing. There is nothing at all unusual about fasting for 40 days but you need to understand what you are doing in order to fast safely - and more importantly, to break the fast correctly.

Our bodies are hard-wired to store any excess fat we consume in order to survive future famine-like scenarios. If you starve yourself the excess fat will be consumed first but at a certain point the good flesh (muscle) that you want to retain will be be consumed too.

Self- starvation (i.e. diets) are likely to result in 'yo-yo' dieting with more weight being regained after the diet than was lost during it. A saner approach is to continue eating normally while gradually eliminating calorie-rich but nutritionally-poor foods. So if you normally eat a 250 gm block of chocolate each week (2250 calories)and you 'starve' yourself by no longer eating that, then at the end of a year you would have consumed 117000 calories fewer than normal and would weigh 13 kg less without having done anything else different.