How do people with eating disorders (specifically not eating enough) manage?

For other athletes, you don’t have to look further than to your own sport. Almost all the climbing specialists like Isaac del Toro, Richard Carapz, Valentin Paret-Peintre and so on are small, skinny guys with no concernable excess fat on their bodies. And yet they eat a lot, especially during a grand tour. They simply have to, because they sometimes burn up to 10k kcal in five hours during a long mountain stage. But every calorie, and every gram from different food groups they consume during a tour, and also during training periods, will be calculated and counted, so they regulate their weight and stay skinny even though few people in the world eat that much food regularly.

I think you’re kind of pathologizing there. If you’re getting that feeling while working at your desk job, you probably need to be eating a healthier diet. But there’s nothing weird or unhealthy about needing to fuel up with some simple carbs during sustained physical activity.

True enough. But it’s more complicated than that. When I was a younger hiker/backpacker I sort of thought the “quick energy” aspect of sugar snacks, carbs and salty treats, and the heavy exertion meant I didn’t really need to worry about precise nutrition. It will catch up to you though, about day 3 or 4 maybe on the trail. Protein, and plenty of it, is crucial for muscle repair and maintenance, among other things.

‘Pathologizing’ might be a little extreme, but I admit after posting that I did realize it may have sounded like I was taking an unfair shot at the OP, who sounds in general like they have a pretty healthy lifestyle. Sure, an occasional simple carb pick-me-up can’t hurt in a pinch.

I think my larger point is still valid: that even though some people might not be eating as much as those who have a more ‘normal’ diet, the ‘normal’ diet, meaning a typical American-ish carb-heavy diet, may lend itself more to ‘energy crash’ situations than a lower calorie diet might.

For people with true eating disorders, I believe the answer is they do it until they no longer can, then they overcome their eating disorder (usually with help), or they die. Bonking is not the same, because in an exercise context, it presumes a certain level of fitness and nutrition for starters. Anorexia is not sustainable, so they are not ‘managing’. They are wasting away. They either eat just barely enough not to die - which, IMO, is not managing - or they die.

Disclaimer..I’m on a very restricted diet because of stubborn diabetes.

I’m really close to the edge of starvation all the time. I can’t grab a candy bar, much.

When you get to the point of weakness (bonked) it’s very uncomfortable and your knee jerk is to grab a quick sweet snack.

I have found eating a citrus fruit can get me to my next protein rich snack or a meal.

YMMV

I would think humans are adapted to be able to continue functioning, even at a high level for short periods, while handling a calorie deficit. It probably takes a severe case of malnutrition to start degrading someone’s ability to manage/function.

I am no elite athlete, but I ride a bicycle a lot, and do a lot of walking and hiking. On bike trips, where I am riding 40, 50, 60 miles per day for consecutive days, hauling my bike, gear, and my butt over hilly terrain, I eat pretty much everything I normally eat and in normal quantities, and carry snack bars, nuts, and occasionally sports drinks for in-between meals. I could eat less, but having bonked a few times in my youth, it sucks.

Humans are most definitely adapted to operating under a calorie deficit. The modern 3 squares a day plus snacks, is probably widely out of the average or norm in human history. Now today, it takes “practice”, a lot of people think they will probably die if they miss lunch.

I generally do carry gels on rides, though I’ve either forgotten or miscalculated a couple of times.

This is something that I contemplate often. As I mentioned in my original post, I’m about 20 lbs overweight. I have also, on a few occasions in the past, had the odd flu-like thing that left me with a significantly reduced appetite for a couple of weeks, without any associated bonk-like thing, so I am convinced that there is a psychological component in my case.

I know one thing. “Bonk, bonking and bonked” are now part of my vocabulary.

What about “bonkers”?

In US English “bonkers” means “crazy”. And AFAIK has no other slang meanings.

My senior year of college I (a man) went from about 205 pounds to about 155 pounds.

Now, a lot of that can be directly attributed to the fact that I stopped working out, and went on a bit of a drug binge, but I also stopped eating regularly. Every couple of days I’d get some fast food meal, but between then I was living on snacks from a gas station - soda, chips (the “crisps” kind), and candy.

(I promise I got better. Well, relatively speaking)

Anyway, I frequently got light headed when I stood up. I certainly didn’t have the energy to exercise - I was much more inclined to rot on my couch. Hunger pangs eventually subsided, but at that time I didn’t mind that empty feeling in my stomach; if anything, I felt most sluggish right after I’d finally break and get a burger and French fries.

I never got to such a severe deficit that it jeopardized my health, but I certainly did myself no favors. What’s interesting is how resilient the body is, so I regained my muscle size within a few months of clean living and exercise.

But, to answer the OP, people with eating disorders are either eating and purging, or they’ve become so accustomed to starvation that their body is past the point of hunger pangs. Or they’ve gotten to the point that they don’t have the energy to be active at all.

I have known two women who died of anorexia. One was around 20 and the other about 40 and a good friend of my wife’s. In the latter case, the explanation was that she had begun to metabolize her heart muscle. Apparently her eating disorder started when she was raped and I have wondered if she was subconsciously trying to make herself unattractive.

The other woman was the daughter of a neighbor, who was actually a doctor. But I don’t know any details.

On the other hand we are friends with a woman who weighs around 80 lb, at 5’2". She would like to gain weight but just cannot eat much. She used to be a dancer with the Canadian Ballet and most of her friends from that became grossly overweight after they retired.

You’ll never believe this, but it really happened! Kurt Gödel, one of the most brilliant mathematicians who ever lived, was decidedly less skilled in more mundane matters, such as dressing and feeding himself. His wife ordinarily took care of such things, and when she became ill enough to be hospitalized, Kurt stopped eating. He actually starved to death, as an official cause of death.

For two or three years, I had little or no appetite. It got to the point last year when I could often only eat one bite of food before having to quit. I mostly didn’t want to eat at all.

I finally went to the doctor and was found to be severely deficient in Vitamin B12 and was suffering from pernicious anemia. My Vitamin B12 was so low that the local hospital doesn’t (or maybe can’t) measure levels that low. All they could say that my Vitamin B12 levels were below 129 pg/mm.

For the past year, I have been giving myself a Vitamin B12 shot every other Friday. Now, my Vitamin B12 levels are high in the desired range of Vitamin B12.

There are all kinds of guides on how many “reps” it takes to gain muscle, but all that requires adequate nutrition. There are even special dietary supplements (protein powders, carb powders, etc.) designed for people who cannot eat that much in the form of food.

Very anecdotally, a skinny friend of a friend would hit the gym but it supposedly took him “years” to get “strong”.

I’d heard that was because he had paranoia problems and was unwilling to trust food prepared by anyone other than his wife.

Would you say that your appetite situation has improved in the past several months?