Sodium also provides a fairly potent example that superstimulus theory makes more sense than setpoint theory. Salty foods are tasty because they are salty, not because the lack in other nutrients.
The same appears to be true for sugar. Adding sugar to foods generally makes them taste better (even foods that we don’t think of as sweet, like french fries and tomato sauce); if setpoint theory was true, we would expect those foods to taste no different as long as haven’t significantly altered the nutrient density.
“Sugar” typically refers to sucrose, chemical compound C12H22O11. In humans, it is respired, with oxygen, to extract the chemical energy and leave behind chemical compounds at lower energy states, not too different from combustion of hydrocarbons.
Because of the small difference between the operating temperature of human bodies, and the temperature of the preferred environments for humans, the effeciency of this energy conversion (chemical to mechanical) is quite low compared to that achieved in well-insulated combustion chambers., which exploit the higher efficiencies possible at higher temperature gradients.
Using sugar for human consumption is, in a sense, quite wasteful.
I’m not sure what this has to do with the thread, although it is interesting. Can you back up your conclusions with some data? Assuming sucrose is metabolized in the Kegg pathway, the energy generated is easily calculable. I haven’t found good numbers on combustion engine efficiency for running on sucrose (how does one design such an engine?); my understanding was that even petrol engines have very low efficiencies, but I could be wrong about that.
You are partially correct: I have erred in deeming the thermal efficiency of typical high-T-gradient heat engines greater than that of humans (whose organs exploit more modes of energy conversion than those in a heat engine).
However, the conclusion is robust when comparing from the appropriate baselines. To find the total energy-to-mechanical-energy conversion efficiency, you have to factor in the energy losses in generating the sugar to begin with. This gives sugar cane as having the highest photosynthetic efficiency of 8% (light energy to sugar chemical energy).
That must be applied against the 28% thermal efficiency (sugar energy to mechancial energy) I calculate for humans [1], leaving 2.2% net light-to-mechanical efficiency (neglecting distribution energy costs for the sugar).
This is still inefficient compared to other means of using the same sunlight. Taking a characteristic solar cell efficiency on the low end of 6% (light to electricity), with a characteristic efficiency of 90% (electricity to mechanical) gives a 5.4% net light-to-mechanical efficiency—still significantly higher than that of growing sugar and feeding it to humans!
[1] Human efficiency estimated from the following assumptions: 816 Cal/hr burned by a 200 lb individual climbing stairs at 0.30 m/s; this gives an energy consumption rate of 952 W and mechanical output of 267 W, or 28% efficiency, though again this is only sugar-to-mechanical efficiency.
Using sugar for human consumption is, in a sense, quite wasteful.
I claim, that given sugar, using it for human consumption is one of the least wasteful things to do with it.
This is still inefficient compared to other means of using the same sunlight.
In the future, if there is an option between powering organic people with sugarcane-produced sugar and powering cybernetic people with solar cells, and we can choose to be either organic or cybernetic, then your argument will be valid—assuming there are no other options, which is silly. For right now, people need food. Converting sunlight into other forms of energy in other ways is fine and good, but personally, I would also like to keep growing food for me and my brethren.
though again this is only sugar-to-mechanical efficiency.
This is a big caveat. A typical person burns much more energy maintaining homeostasis than they do in moving. Following that, brain activity is the second-largest energy sink. While athletes can quadruple their caloric requirements (indicating that mechanical energy can become the largest drain on energy), I think calculating energy conversion with your example is suspect.
Okay, now I think I see the source of our miscommunication: you’re assuming humans have an important use in addition to manufacturing products, while I wasn’t.
Is your composure of these comments an example of a human manufacturing products?
I still think using sunlight through an organic / metabolic pathway is more efficient form of manufacturing rational discourse than using solar cells and electricity. Unless, of course, you are not human, which might explain your apparent disregard for human utility, but introduces the question of why you are bothering to converse with one.
I’m not disputing your general point, but I hate sugar on foods I don’t think of as sweet. I have a marked sweet/savory divide, with only a few things like butter and flour able to participate in either sort of food. I can sometimes enjoy savory foods that have some added sugar but it never improves them, unless the sugar is there to be food for yeast in a bread product.
You might be misunderstanding my point, or I might be underestimating how much you dislike sugar.
McDonalds (and most other fast food companies, I assume) puts sugar on their French Fries, though most people aren’t aware of this. Likewise, when I make tomato sauces (for pizza or chicken parmesan or whatever), I add about a teaspoon of honey to each quart of sauce, which doesn’t make the sauce taste detectably sweet, but does balance out the acidity and makes the overall taste better. In this way, sugar is sometimes salt-like in that it can improve foods at a threshold that doesn’t make them taste sweet or salty.
I don’t tend to eat fast food. Don’t like tomatoes. But I cook for myself a lot, and have made recipes that are savory and call for sugar, and tried them both with and without said sugar, and they’re better without. I accidentally got a bunch of cans of kidney beans with added sugar a few weeks ago and made soup with them without noticing that they had sugar in them, and I could taste the difference in the soup—it was fairly unpleasant for me to eat, while others liked it fine.
I don’t understand—how does it support the general argument? Because other people liked my soup? I daresay they’d have also liked it if I’d used sugarless beans.
Also, what I was really thinking was you provided an example of a company that makes beans with sugar. Ostensibly, the only reason to add sugar to canned beans is to make them taste better—though that obviously backfired for at least one of their customers.
Sodium also provides a fairly potent example that superstimulus theory makes more sense than setpoint theory. Salty foods are tasty because they are salty, not because the lack in other nutrients.
The same appears to be true for sugar. Adding sugar to foods generally makes them taste better (even foods that we don’t think of as sweet, like french fries and tomato sauce); if setpoint theory was true, we would expect those foods to taste no different as long as haven’t significantly altered the nutrient density.
“Sugar” typically refers to sucrose, chemical compound C12H22O11. In humans, it is respired, with oxygen, to extract the chemical energy and leave behind chemical compounds at lower energy states, not too different from combustion of hydrocarbons.
Because of the small difference between the operating temperature of human bodies, and the temperature of the preferred environments for humans, the effeciency of this energy conversion (chemical to mechanical) is quite low compared to that achieved in well-insulated combustion chambers., which exploit the higher efficiencies possible at higher temperature gradients.
Using sugar for human consumption is, in a sense, quite wasteful.
I’m not sure what this has to do with the thread, although it is interesting. Can you back up your conclusions with some data? Assuming sucrose is metabolized in the Kegg pathway, the energy generated is easily calculable. I haven’t found good numbers on combustion engine efficiency for running on sucrose (how does one design such an engine?); my understanding was that even petrol engines have very low efficiencies, but I could be wrong about that.
You are partially correct: I have erred in deeming the thermal efficiency of typical high-T-gradient heat engines greater than that of humans (whose organs exploit more modes of energy conversion than those in a heat engine).
However, the conclusion is robust when comparing from the appropriate baselines. To find the total energy-to-mechanical-energy conversion efficiency, you have to factor in the energy losses in generating the sugar to begin with. This gives sugar cane as having the highest photosynthetic efficiency of 8% (light energy to sugar chemical energy).
That must be applied against the 28% thermal efficiency (sugar energy to mechancial energy) I calculate for humans [1], leaving 2.2% net light-to-mechanical efficiency (neglecting distribution energy costs for the sugar).
This is still inefficient compared to other means of using the same sunlight. Taking a characteristic solar cell efficiency on the low end of 6% (light to electricity), with a characteristic efficiency of 90% (electricity to mechanical) gives a 5.4% net light-to-mechanical efficiency—still significantly higher than that of growing sugar and feeding it to humans!
[1] Human efficiency estimated from the following assumptions: 816 Cal/hr burned by a 200 lb individual climbing stairs at 0.30 m/s; this gives an energy consumption rate of 952 W and mechanical output of 267 W, or 28% efficiency, though again this is only sugar-to-mechanical efficiency.
I claim, that given sugar, using it for human consumption is one of the least wasteful things to do with it.
In the future, if there is an option between powering organic people with sugarcane-produced sugar and powering cybernetic people with solar cells, and we can choose to be either organic or cybernetic, then your argument will be valid—assuming there are no other options, which is silly. For right now, people need food. Converting sunlight into other forms of energy in other ways is fine and good, but personally, I would also like to keep growing food for me and my brethren.
This is a big caveat. A typical person burns much more energy maintaining homeostasis than they do in moving. Following that, brain activity is the second-largest energy sink. While athletes can quadruple their caloric requirements (indicating that mechanical energy can become the largest drain on energy), I think calculating energy conversion with your example is suspect.
Okay, now I think I see the source of our miscommunication: you’re assuming humans have an important use in addition to manufacturing products, while I wasn’t.
Is your composure of these comments an example of a human manufacturing products?
I still think using sunlight through an organic / metabolic pathway is more efficient form of manufacturing rational discourse than using solar cells and electricity. Unless, of course, you are not human, which might explain your apparent disregard for human utility, but introduces the question of why you are bothering to converse with one.
You might give him information about how to better make paperclips, or he might persuade you to help him.
Alternatively, he’s engaging in a very protracted joke.
I’m not disputing your general point, but I hate sugar on foods I don’t think of as sweet. I have a marked sweet/savory divide, with only a few things like butter and flour able to participate in either sort of food. I can sometimes enjoy savory foods that have some added sugar but it never improves them, unless the sugar is there to be food for yeast in a bread product.
You might be misunderstanding my point, or I might be underestimating how much you dislike sugar.
McDonalds (and most other fast food companies, I assume) puts sugar on their French Fries, though most people aren’t aware of this. Likewise, when I make tomato sauces (for pizza or chicken parmesan or whatever), I add about a teaspoon of honey to each quart of sauce, which doesn’t make the sauce taste detectably sweet, but does balance out the acidity and makes the overall taste better. In this way, sugar is sometimes salt-like in that it can improve foods at a threshold that doesn’t make them taste sweet or salty.
I love sugar. Love it. But not on savory foods.
I don’t tend to eat fast food. Don’t like tomatoes. But I cook for myself a lot, and have made recipes that are savory and call for sugar, and tried them both with and without said sugar, and they’re better without. I accidentally got a bunch of cans of kidney beans with added sugar a few weeks ago and made soup with them without noticing that they had sugar in them, and I could taste the difference in the soup—it was fairly unpleasant for me to eat, while others liked it fine.
Thanks, that answers my question, and even provides an anecdote supporting (or at least not disputing) the general argument.
I don’t understand—how does it support the general argument? Because other people liked my soup? I daresay they’d have also liked it if I’d used sugarless beans.
Also, what I was really thinking was you provided an example of a company that makes beans with sugar. Ostensibly, the only reason to add sugar to canned beans is to make them taste better—though that obviously backfired for at least one of their customers.