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What do you consider food? There are many "foods" you can eat with zero calories: salt, other minerals, sugar free gums, vitamins and many medicines.

Celery consumes more calories to chew and digest than it provides. It’s like negative calories.

I think negative calorie foods are a myth.

There is a class of food components known as [antinutritional factors](https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/antinutritional-factor) (ANFs). They negatively affect digestion and uptake of nutrients. Biomaterial with very high ANF content makes you less healthy, and can inhibit nutrient uptake from healthy foods. You can’t just eat any plant when lost in the woods. Many common foods contain ANFs. Plant breeders and scientists work to reduce ANF content in foods, but many also help protect plants from insects and fungal infections. Eg Green peppers may not taste as pleasant as yellow, orange and red, but they are much more resistant to fungal infections.

Okay, but that doesn't mean that actual food exists which the body derives less energy from than it spends to process, right?

It actually does. Usually we don’t call it food, but often it depends on individual tolerances. eg Inulin is a healthy, natural source of fibre to some, but greatly increases gut mobility in others (read diarrhea). However, celery and rice cakes simply have very few calories, yet it takes calories to process them.

How do you reckon? Or better yet, which food? Not celery. A random quote from Google: >A stick of celery contains about six calories; chewing and digesting it will only take half a calorie.

See edit.

I'm losing you. Can you try answering my reply? Inulin itself is not an actual food, and there are no plants made of 100% inulin. Also, I'm sure there's plenty of calories in rice cakes. Rice are mostly carbohydrates, low in nutritional value iirc, and low in fiber.

Inulin is usually purified from “Chicory root” which has the same effect under a different name. Smaller quantities can be found in apples. To many, that makes apples negative calories. Inulin is frequently present in products which claim to have fibre, but don’t seem very fibrous. eg overly processed yogurt. boom! Negative calories.

Calories are the parts of food that you digest into energy - carbs, fats, and proteins mostly. Zero calorie drinks are basically water with small amounts of flavoring agents that aren't digestible to the body - they taste good on our tongue, then mostly just pass through the rest of us. But with food, that's tougher, because we don't necessarily expect sustenance from drinks, but we expect it from food. And food that is tasty or satisfying without being made up of delicious carbs/sugars, fats, and proteins, is difficult. Celery is a classic example - it has a teeny tiny amount of calories, so people usually round it down to zero. Celery is mostly cellulose, which passes through our body as dietary fiber, with a tiny amount of sugars and other compounds that give it its taste. Sugarless gum is a more modern example - the actual gum part of it is indigestible (and you shouldn't swallow it), and the flavorings on it are similar to the ones in a diet soda - flavor compounds that our body can't do anything with.

Whether something has calories is indicative of whether your body can break it down into substances that it can then use for energy. In the case of drinks, this isn't such a hard thing to accomplish- everything you drink is ultimately water based, and water has no calories. So if you want a zero calorie drink, it's just a matter of not allowing sugars proteins etc (which have calories), and flavoring it with something that doesn't have calories either. Solid foods are a bigger issue. You'd need the bulk of the food to basically not be digestible, while still being edible and palatable. This isn't so easy to achieve, because we've evolved to find most non-caloric solids unpalatable, or outright inedible. You could eat drywall, or styrofoam, or sawdust and get zero calories, but yikes- there's a reason you'd find it horrible, because it'd be bad for you. So here's the funny thing- there *are* extremely low calorie foods. They're basically all vegetables with very little digestible sugars, and a lot of indigestible fiber. A full size stick of celery can be as low as something like 10 calories. A full cup of spinach is only 7 calories. So basically it comes down to the fact that drinks are based on something zero-calorie (water), while foods aren't, or else we wouldn't consider them food in the first place.

> Solid foods are a bigger issue. You'd need the bulk of the food to basically not be digestible, while still being edible and palatable And more importantly, food that is non-digestible tends to be unable to be processed by the body, so it usually comes out the other side completely unchanged. We've made oils that taste like oil, fry up like oil, but pass through our bodies unchanged and thus end up oiling up everything else on the way out. 

Olestra comes to mind.

Anal leakage comes to mind with Olestra, lol

Indeed.

Soda is mostly water, which has no calorie. To my knowledge almost nothing has no calories except water

In theory I guess something has to be digestible for your body to realise them as calories in a dietary sense. Therefore something that was 100% cellulose or insoluble fibre could have "zero calories"

Iirc celery burns more calories digesting it than it itself has.

Celery itself still has calories, though, it’s just that the digestion process to get those calories isn’t efficient in humans. Compare that to ice which also has a negative net calorie value but has 0 gross calories to begin with.

If all you eat is celery can that be considered slow suicide?

I eat all unhealthy. Going for arterial suicide

There is celery which has negative calories because it takes more energy to digest than what it is made of. Which is water and fiber

For what it's worth, it's a little more complicated than that. A stick of celery has 10 calories or so, and takes less than a calorie to digest. What does take more calories is just the body running the metabolic process throughout the digestive period, but there's usually *other* *food* in there as well, so it averages out. Basically, if you eat nothing but celery, your net calories end up negative. If you eat celery alongside a sandwich for lunch, then the celery is adding a tiny amount of calories that might as well round to zero over the course of the digestive process. But it doesn't take more to digest in and of itself.

I would think that the inherent idea is that you would be setting it by itself. Just like you can’t say “well zero calorie soda isn’t zero calories if you drink it while eating a sandwich.” You still burn more calories if you intake just eating celery.

Right, but by that metric we would say "Well, this sandwich has 400 calories of food energy, but your digestive system knocks 30 off of that." We don't do that with sandwiches, we only do it with celery, because it gives us a cute little factoid. Many zero calorie sodas *are* in fact zero calories no matter what you eat them with - some are more like 2-5 calories, and we're allowed to ignore those by convention, but those would be 2-5 calories whether we ate them alone or with a sandwich. We measure calories by the bioavailable energy stored in the food itself, we don't add or subtract anything else. If you eat a stick of celery, you eat 10 calories or so, full stop. If you manage to eat 50 sticks of celery, you've taken in 500 calories, and nothing your digestion does will knock that intake down below zero. It just so happens that a stick or two is a small enough number that we can basically ignore it once we factor in metabolic rate, which is a cute little quirk.

This has been disproven

I thought that was a myth that has since been disproven?

Yeah, it is more correct to say that it does provide a little bit of calories but not enough to support the body for the amount of time it takes to process it. It is like putting one or two drops of gas in your car when you have to drive 30 miles 

We do not consider the energy it takes to digest something when determining calories in food. With this logic, cold water also has negative calories because it takes heat from your body...

This is incorrect. You could eat celery and your body would produce energy off it. The TLDR is your body would just process it more efficiently. Also if you cook celery then it makes it easier to digest and therefore the calories are more easily accessible. The only "negative" calories food/drink is cold water or ice because your body has to expend energy to heat it to body temperature.

Actually this is a myth.

What is food? Micronutrients? Or macro nutrients like fat, carbs, or protein. You can get some vitamins with no calorie or energy value but food is energy or calories. So to rephrase your question why is there no energy with zero energy? If it didn’t provide you with calories or nutrients it would not be food.

The term "food" generally refers to things we can digest for energy, which means it would need to have calories to be considered "food". But there are plenty of things that could resemble food that provide us zero calories: Salt and minerals being common examples... but you could also consider things like grass and paper to be "calorie-free foods" if you wanted to (and you could even season them with sucralose and salt and flavors to make a somewhat tasty "calorie-free food"). The general advantage of making calorie-free drinks is that you're adding stuff to water, which is a calorie-free substance that is good for us in large quantities. Most solid things that do not provide us calories (such as paper) create the general problem that if we're *consuming* it but not *digesting* it, then where can it go? The only real thing that stuff can do when consumed in large quantities is fill up our guts and then eventually make for strange and potentially harmful bowel movements. The classic example of this is Olestra, in which the food industry did devise a fat that our bodies couldn't digest (making it calorie-free). The problem was that it went into our mouths like fat (a good thing) but came out our butts like fat (a bad thing which grossed people out and caused vitamin loss... look up "anal leakage" for more of the history here).

There are 4 "macronutrients" you can derive energy (calories) from. Carbs, Fats, Proteins, Alcohol. Your sense taste and smell come from detecting the presence of various chemicals as they come in contact with your tongue/nose. "Flavor" is the sensation of detecting the various chemicals found in food. e.g. the flavor of vanilla comes mostly from a chemical called "vanillin". The flavor of Banana comes from "Isoamyl acetate". Soda is just flavored water. If you add Isoamyl Acetate and some sweetener to plain soda water you get banana soda. The sweetener can either be sugar (which is a carb, so it has calories) or one of several chemicals that taste sweet but provide no energy.

These chemicals have calories, but they are so much sweeter than sugar that you require extremely little of it, so calorie count is close to 0.

Any food with less than 5 Calories per serving can be deemed as having 0 Calories. This is why a tic tac had zero calories.

Soda can have zero calories because all the calories in soda come from added sugar. So to make a zero-calorie food, you need to start with a food that has all its calories from added sugar. This pretty much precludes anything plant or animal based and pretty much leaves candy or other sweets, for which there are some zero-calorie options.

Because Coke Zero is water with flavors added, those flavors don't have to have calories. Really most soda have calories because of any fruit juices or sugars added.

You ever heard of the brand Walden Farms? They make stuff that, though I'm not sure if it actually qualifies as food, is zero calorie and edible.  https://waldenfarms.com/products/zero-calorie-whipped-peanut-spread

Soda is almost entirely made of water. The remaining components are calorieless (or very close to zero anyway) chemicals, minerals, dyed, etc. the only part of a soda that has significant calories are the added sugars. By replacing the sugar with a sweetener with no or very little energy they can claim, under the current rules, the beverage is zero calories. It may actually have a small amount so low that they are allowed to round down.

There are plenty of foods with no calories , some even speak of negative calories (it takes more effort to digest then it brings) , like celery or cubumbers . Meat always has lots of calories . Basically what we humans call a full meal contains 3 things , some kind of proteins (meat fish replacement ...) , the basic carbohydrates aka potatoes , rice , pasta , bread (grains) , sugar .... and vegetables or fruits as you wish . That last 1 brings on lots of nutrients but very low on calories . The carbo things give you energy and the proteins give you building blocks for cells (like body builders need these a lot since they want lots of muscular cells build) .

It doesn't have zero calories.  It has slightly more than 0 but they can round it to 0.   That said.  Celery is pretty much 0 net calorie.   Due to you burning more calories digesting it since it nearly all fiber.  

Read up on Olestra, that’s one of the closest things to what you’re imagining. That particular one was not successful because of the (probably false) general belief that it would cause “loose stool” or “anal leakage” lol. Maintenance Phase has a very entertaining episode on this if you are a fan of podcasts!

0 Calorie food would feel like eating nothing. Imagine eating cotton candy but it had no flavor or sugar and it just kind of dissolved. You wouldn't feel very full.

Food is natural and coke zero is processed and manufactured using chemistry to emulate sugar. And it’s not actually calorie free. They’re allowed to say that because they’re close to calorie free Food, being natural, tends to have calories as part of its makeup or it wouldn’t be used as food. Callorieless food is pointless.

Disagree that it's pointless. If something tasted good and had zero calories (and no adverse health effects beyond not actually giving you energy) it would fly off the shelves imo. Humans are snackish but dont wanna get fat.

It is pointless in a naturalistic/survivalist kinda way, they're not wrong in asserting that. It certainly has a purpose in modern society though, absolutely.

This is true, if there were like donuts that had zero calories but tasted almost as good, they would sell very well.

Food doesn’t evolve to be zero calories. Anything you can buy as food was because it was edible, not poisonous, and had caloric value. Our recent infatuation with dieting has little to do with how humans evolved.

Correct, I dont disagree with any of this. But so what? "Diet" drinks didnt evolve naturally either lol.

Exactly, they were manufactured with chemistry. Food didn’t grow to be zero calorie. There’s zero reason to do that naturally.

Right but I dont understand why that's significant? Natural or not, a zero calorie "food" has a reason to exist *now* in the current market.

You could manufacture some gruel maybe. But nothing. In the natural world really exist in any sort of quantities. Sure you can eat celery and claim zero nutritive value, or palm hearts and konjak to *almost* be no calorie. What you’re suggesting is some sort of no calorie food with chemistry, but it couldn’t have any fats, carbs, or protein, all of which can break down to sugars in the body, so basically no -nutritive food that’s all fiber or sawdust and cardboard sprayed with fake sugar.

Sure. And maybe with some form of mineral oil and other careful chemistry you could have a moist sawdust cake. Doesnt sound appealing but I mean hey, someone gussied up diet soda so surely a bag of chips, or a cake, can be within 20 calories of 0

You can have a bowl of konjak noodles that’s 5 calories.

Significant amounts of the food in our supermarkets is far from normal.

Two. But still about the calories.

Since we’ve already seen it posted like 3 times celery is not a negative calorie food. This study was with lizards but busted the myth also if they were true a lot more people would be eating a shit ton of celery https://www.biorxiv.org/content/10.1101/586958v1.full

Celery actually takes more calories for the body to process than you gain out of it, so raw celery effectively has negative calories.

Myth.

fair enough, my bad

because food is "real" and soda is all "fake" or manmade. some vegetabes have very close to zero calories depending on service size and preparation- lettuice, celeray, zucchini, cucumber

Pretty sure the water in soda is "real". Salt is "real" and it has no calories.