1744: Metabolism

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I have this weird thing where if I don't drink enough water, I start feeling bad and then die of dehydration.
Title text: I have this weird thing where if I don't drink enough water, I start feeling bad and then die of dehydration.


Eating is fundamentally a process where energy from food gets absorbed into the body in order to drive every cellular process in the body. Energy that is absorbed but not needed in the short term gets converted and stored as body fat. This is called metabolism. Consuming too much food and not exercising enough are major factors for obesity, which is a problem in many first world countries today, especially in the United States.

For obese people, losing weight is often an enormously difficult task. Standing in stark contrast, there are also lean people who do not seem to ever gain any weight even though they appear to eat whatever and however much they want. This leads some people (including the lean people themselves) to believe that one can have a special metabolism where excess food energy somehow does not affect the body. This belief is common, though not supported by scientific evidence.[actual citation needed] The comic makes fun of that kind of notion. While Cueball describes to White Hat how his metabolism is "special" (the phrase "one of those" implicitly meaning unusual), he is in fact only describing the normal case: no matter what he eats, his body converts the food to energy and stores any excess food as fat which stays in his body for future use.

The title text stretches this further, telling about the normal habit of drinking water (and the consequences of not drinking it) as something odd. Starting to feel bad at first and eventually dying if refraining from drinking for too long a time are perfectly normal consequences of dehydration. This was also touched upon in 1708: Dehydration, in which Megan spent all day researching whether low-grade dehydration is really a thing -- ironically forgetting to eat or drink at all, to predictable results.

Obesity has only fairly recently become a public health issue due to lifestyle changes brought on by technologies such as industrialization and trade. Human bodies evolved under conditions where it was hard to ever find enough to eat, so to store as much excess energy as possible as fat was a beneficial adaptation. Historically, stored fat would be consumed during hard times that was sure to come. The act of collecting food through farming or hunting/gathering also demanded physical labor which limited the amount of excess energy that would remain. In comparison, people nowadays hardly need to expend any energy to buy their food from a nearby market. They also have much more sedentary lifestyles and rarely ever go hungry. Without an active commitment to exercise more or eat less, there would almost never be a shortage of energy and no chance for body fat to be used. Randall has previously shown how bad his health becomes when he starts eating lots of fat (or sweet) food in 418: Stove Ownership.

There are many rational explanations for why some people might not gain weight despite eating a lot. For example, it's possible that they only eat a lot during special occasions and social gatherings, where they are easily seen eating. On more private occasions when no one is watching, they could just as well eat much less or even skip entire meals. They might also lead a much more active lifestyle and thus require more energy than an average person despite their thin appearance. Other less pleasant reasons might include chronic diseases, parasite infections, or eating disorders.

This is the second comic in a row about food, the previous being 1743: Coffee.


[Cueball, on the left, and White Hat are sitting on chairs on either side of a table, facing each other. They each have plates of food and glasses of some beverage set in front of them. Each has picked up a portion of food on a fork to eat it.]
Cueball: I have one of those metabolisms where I can eat whatever I want and my body converts it to energy and stores the excess as fat.

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I think the comics explanation should include dieticians. 14:58, 10 October 2016 (UTC)

A reference on the topic of metabolic energy balance and common beliefs surrounding it: http://ajcn.nutrition.org/content/95/4/989.full 17:47, 10 October 2016 (UTC)

If it was White Hat saying this, I'd expect him to be literally able to eat whatever he wants, even items that are not normally edible. It is not, however (which is strange, because, even aside from that alternate interpretation, it sounds a lot like his style). -- 02:56, 11 October 2016 (UTC)

I'd say in that case it had to be Beret Guy instead of White Hat. Elektrizikekswerk (talk) 07:31, 11 October 2016 (UTC)
I agree - not sure why I mistook one for the other. -- 12:11, 11 October 2016 (UTC)

I have one of those metabolisms where if I eat more than what I need, I sweat a lot during the night and I never fatten. I'm always underweight. é_è Seipas (talk) 09:07, 11 October 2016 (UTC)

The explaination is mistaken. It is indeed possible to eat and not gain weight, and well document and most parts of it understood by medicine. Excess energy is only stored as fat if the body is stressed, you can piss out the sugar or the intestines can absorb less. The problem with the idea is that is hard to impossible to correct what your body does in this regard which makes is a red herring for the already overweight. 16:45, 11 October 2016 (UTC)

It's even worse: if you try some diet to reduce weight and you start feeling hungry due to this diet, your body will interpret it as signal that it needs to work harder to preserve and/or obtain energy. When you stop the diet, you will then gain even more weight, which is also known as Yo-yo effect. Overweight people who already tried multiple diets, some of them based on bad ideas, will typically get more fat from the same food than people who never cared. -- Hkmaly (talk) 13:37, 13 October 2016 (UTC)

Technically, Cueball says he can eat "'whatever I want," which would imply he could eat traditionally non-edible items. I don't think this is actually intended based on context, but... (talk) (please sign your comments with ~~~~)

Mentioned already in my comment above (and the discussion after it). It would probably have been intended if that was Beret Guy, but that's not Beret Guy. -- 20:48, 14 October 2016 (UTC)

It may be coincidence but this comic was published the day before the Yom Kippur (Day of Atonement) Jewish fast. There was a reference to the Jewish calendar a few comics ago. (talk) (please sign your comments with ~~~~)

This is stated too strongly. Most of our energy consumed goes toward our basal metabolic rate, which does seem to vary among individuals. 19:22, 14 October 2016 (UTC)

You can think about this topic as much as you want. The final answer is sports. Always. Beautiful women do sports. REAL men do sports. It's all so simple. (talk) (please sign your comments with ~~~~)

There actually is a gene that controls insulin response to blood sugar, and it comes in two allies, one for low, and one for high. These mix, giving low, medium, medium, high.

It turns out that "low" corresponds to people that have trouble putting on fat, "high" corresponds to insulin resistance diabetes, and "medium" corresponds to most people who wind up overweight / needing to exercise.

Keybounce (talk) 21:15, 21 October 2016 (UTC)