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What is the energy amount in four litres of beer?

  1. Oct 6, 2013 #1

    I wonder how much physical work I have to do to burn four litres of beer (2.8%) which I drink every day.

    This is a serious question because I have some overweight while being a beer-lover.

    A friend of mine told me that alcohol (C2H5OH) is converted to pure sugar in the body.

    This is thus one part of the energy input.

    My friend also told me that there is a kind of sugar called maltosis in the beer.

    Best regards, Roger
  2. jcsd
  3. Oct 6, 2013 #2


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    Just look at the calorie count on your beer bottles. That's how many calories you need to burn to have a net-zero effect.
  4. Oct 6, 2013 #3


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    The calories are highly variable:

    You should look up the nutrition information for your prefered brand.

    Of course, you are talking about ~11 servings of 12 oz, which is quite excessive. So even at a fairly low level of 100 calories per serving that is about 1100 calories each day. That amount of liquid calorie intake will definitely contribute to obesity. To burn that many calories will require jogging a steady 5 mph pace for about 90 minutes per day.
  5. Oct 6, 2013 #4


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    Let's give you the benefit of the doubt and assume it is a fairly light beer at 100 calories per 12 oz. Then 4 liters of beer works out to about 1100 calories. Let's further assume that you weigh 100 kilograms (220 pounds). In order to burn this, you would need to run about 7 miles at an 8-10 minutes/mile pace. You would need to cycle for about 2-3 hours at a 12 mph pace, or walk for 3-4 hours at a 3-4 mile/hour pace.

    If we just do a straightforward physics energy calculation, 1100 food calories is equivalent to:

    1100 * 1000 * 4.2 = 4.6 million Joules

    This is equivalent to lifting your assumed 100 kg body a distance of

    h = 4.6E6 J / (10 m/s^2 * 100 kg) = 4600 meters or about 15,000 feet

    So climbing a 15,000 foot mountain would be required to burn up the 4 liters of beer. This assumes that your body is 100% efficient. In practice, you body is probably less than 50% efficient, so you would only need to climb about a 5000 foot mountain.

    No matter how you slice it, it takes a lot of exercise to burn off 4 liters of beer.
  6. Oct 6, 2013 #5


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    Not to mention amount of peeing required to get rid of the water.
  7. Oct 6, 2013 #6

    Diet is the best way to reduce excess weight. Exercise is the next best. First cut out two liters of beer per day. Then use the link and the included chart to choose exercises that you can do without feeling it's a chore which you can put off. The data are for one hour of exercise. The best are running 8 mph (13 kph), jumping rope and tae kwon do. If you're like most people (at least in the US) you may have to work your way up to 1 hour for many of these which means even less beer. Good luck!


    Here's a calorie chart of some popular beers. Note it's per 100ml (about 3.4 oz). Multiply by 10 to get per liter.

    Last edited: Oct 6, 2013
  8. Oct 6, 2013 #7


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    Maybe he lives in one of those places where it's not safe to drink the water...
  9. Oct 7, 2013 #8


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    Even so 4 liters is excessive.
  10. Oct 7, 2013 #9


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    Equivalent to a bottle of 15.2% wine:

    Take care.
    Last edited by a moderator: Sep 25, 2014
  11. Oct 7, 2013 #10


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    I make that out to be 11.2 units a day you're ingesting which is 3-4 times the healthy limit. I realise you didn't ask for any advice on this but I'd encourage you to consider the effect this can have long term.

    To put that in perspective that's roughly equivalent to drinking two litres of vodka a week.
  12. Oct 7, 2013 #11
    That would be maltose.
  13. Oct 7, 2013 #12
    This means 100 calories/bottle (33cl). Looks ok with regard to the link above.

    This is right on the spot.

    This sounds terrible! :smile:

    Jesus, 4.6 million Joules! Please explain 1000 and 4.2

    Jesus, climbing a >1500m high mountain. Is this really true? While I ride the bus to work in the mornings and hardly even walk more than 1km per day (on flat ground) I will only get fatter? :frown:

    It is a good and neccesary thing then that I will begin working out next weekend. My plan is to go to a jym 3 times a week.

    I have to do something because I need myself a nice and beautiful woman...

    Obviously! :smile:

    Thanks for your fabulous scientific explanation!

    But viewing the above link for beer data I have come to the conclusion that average calories are some 150 and average corbonhydrates are around 10 grams.

    On the other hand, I belong to the naive(?) people that don't believe in calories. I am on a LCHF diet by choice (which I forgot to mention) and I fully believe that fat is not that harmful because it mainly "slides through". My reasoning for this is such that why should our bodies be so stupid that it will convert fat into fat? Which is the only way it can end up on my stumoch :smile:

    However, there is no fat in beer. Even though fat carries a lot of calories.

    In beer I have problems with the energy in alcohol and the sugar/maltosis/corbonhydrates.

    There was by the way almost no beer in that link above that contained so little alcohol that I drink (2.8%). I actually saw only one (2.4%, Budweiser Select 55) which contained 55 calories and 1.9g carbonhydrates. Which is an extreme example of a low calory beer.

    While I drink 2.8% and 4 liters I consume 11,2 cl of pure alcohol every evening.

    My beer cans have strangely enough no nutrition declarations on them. Only what they are made of. ALL other "food" has however nutrition declarations on them.

    So I can't tell the amount of carbonhydrates which is very interesting to me. But while the density of beer is almost exactly as that of water, 10grams should equal 10% carbonhydrates. Here it would have been interesting to know the sugar/maltosis part. But let's say 5% sugar.

    Here I can tell you a true story. My stumoch grew, not because of beer consuming, but of orange juice consuming! I drank two liters of orange juice everyday for about three months and afterwards I had gained about 20kg! But I thought "this is natural stuff...".

    So beer did not build my body. Now beer however seems to make me stuck at 100kg. In spite of me following LCHF almost to the extreme. I even eat "King of the Day" at Burger King everyday without bread. And of course with water. Yet I am stuck...

    Best regards, Roger
  14. Oct 7, 2013 #13
    I thank you for your nice advice. I do however need the beer to feel "happy". But I wish I could buy them in lesser strength. But the least strength is 2.2% and they only come in 33cl cans and are not available as sixers. I like the possibility to just grab two 4-packs in the shop without any more fuzz. If I chose 2.2% I would however need to grab them one by one and that takes time...

    Jesus, how lazy can a man be :smile:

    Next step is non-alcoholic. But what's the fun in that?

    Best regards, Roger
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