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Coffee + Sugar = Extra Calories?

  1. Nov 3, 2015 #1
    I am a big physics enthusiast, and I apply my learning as much as possible.

    Today, my literature teacher introduced this idea that when coffee and sugar are combined, new calories are born.

    For instance, coffee (0 kcal) + sugar (100 kcal) = 150 kcal?

    Unfortunately, I only pursued physics and chemistry, so I only have basic biology knowledge.

    Is this true? It seems unreasonable according to the law of conversation of energy and mass.
  2. jcsd
  3. Nov 3, 2015 #2


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    Is there anything more your teacher said on this? Any context that could give a greater clue to what they were referring to? I don't know of any possible way this could be true.
  4. Nov 3, 2015 #3
    He did not provide any specific details about it, although mentioned that it is related with some kind of breaking bonds.

    More generally, I am curious that if there are 'unmetabolizable' calories that can be turned into something that we can use.

    In this case, coffee and sugar combined will create something like this? I am greatly baffled.
  5. Nov 3, 2015 #4


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    I think your literature teacher should stick to literature. Never heard of this. Please ask them for the source.
  6. Nov 6, 2015 #5

    jim mcnamara

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    What you show is impossible in terms of conservation of energy. You cannot add something to a solution and get more calories than you started with, and have it gain energy that was not already there there to start with.

    There are synergistic effects because chemicals may turn on biosynthetic pathways to increase bioavailability or rate of uptake of nutrients or meds:
    Piperine (5mg) + Carvedilol (6.25 mg) increases the effect of carvedilol on Blood pressure by a small amount.

    An example of the reverse: grapefruit juice has an antagonistic effect on bioavailability of calcium channel blockers (hypertension meds).

    There no examples of adding two things together:
    Code (Text):
    [ thing A:  0 kCal +  thing B:100 kCal  giving -> 150kCal ]
    Cannot happen.
    Last edited: Nov 6, 2015
  7. Nov 6, 2015 #6


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    Although the amount of total chemical potential energy in foods cannot change by mixing substances (for the conservation law arguments described above), the usable calories that animals can extract from foods can change upon processing. For example, it has been shown that cooking increases the amount of usable calories from both meats and starch-based tubers (http://www.pnas.org/content/108/48/19199.long, http://blogs.discovermagazine.com/c...food-provides-a-lot-more-energy/#.Vj0f8b-WlAB). However, such effects are not likely to occur for coffee and sugar, both of which should provide calories that are easily digested and absorbed by the human digestive system.
  8. Nov 6, 2015 #7

    jim mcnamara

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    I'm reasonably sure this falls in the bioavialbility column. If you absorb more nutrient per gram of intake you realize more calories.

    Anyway, when you look at how calorie counts for human foods are generated, it is purely based on the amount of energy released by turning said food into carbon dioxide and water in the lab. Not in people, I would like to learn how this is possible in humans -- iff it is. "iff" in the math sense.

    FWIW - I think the zero calorie thing for coffee has severe problems - see powdered instant. When you mix 10g into whot water your drink the whole all the powder in my experience.

    10g - heaping teaspoon - has ~147 calories. Zero calories is bogus.
  9. Nov 11, 2015 #8


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    Perhaps she was referring to the caffeine in the coffee which
    Can make you feel like you have more energy?
  10. Nov 12, 2015 #9


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    A lot of minerals in coffee - who knew.

    147 kJ
    35 kcal
  11. Nov 13, 2015 #10


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    Your link shows 6 calories per teaspoon for instant decaf, decaf is higher in calories. Where are you getting the calorie count for black, unflavored, unsweetened coffee? I am finding 0-6 calories depending on the brand. if you get a sweetened, flavored instant, then it has calories.


    Instant coffee regular 4 calories http://ndb.nal.usda.gov/ndb/foods/show/4281?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=&sort=&qlookup=Beverages,+coffee,+instant,+regular,+powder
    Last edited: Nov 13, 2015
  12. Nov 13, 2015 #11

    jim mcnamara

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