Mainly in an attempt to do something more useful in my resting phase than providing iffy race-route info (oops!), I decided to ponder EtU reliance on alcoholic beverages as a training aid and his question of ‘where do the calories come from?’ 10+ years ago, having spent a good deal of time studying Physiology and Biochemistry (among other subjects) to Post-Graduate level the answer would have been instantaneous. The ravages of time have meant recall is slower, to the point of not remembering. So I dusted off a few text-books, put them back on the shelf and tried the internet instead.
Memory refreshed; this is it in a nutshell. Alcohol is absorbed mainly from the stomach, where it travels to the liver via the blood stream to be metabolised (broken down). It’s this metabolisation process that produces the energy or ‘calories’. 1g of alcohol produces 7kcal. Relating this to other sources of energy 1g of fat produces 9kcal, 1g of protein or carbohydrate produces 4kcal. In practical terms 1 unit of alcohol is considered to have about 8g of alcohol. Half a pint of beer/larger/cider (1 unit) can vary from 85 to 205 kcal depending on the % of alcohol present.
Not to be outdone, I decided to give the books another try and managed to unearth this gem of information which may mean he’s on to something!
‘ … The metabolism of fat produces more water than either protein or carbohydrate
1g fat = 1.07g water
1g starch = 0.55g water
1g protein = 0.41g water
(1g alcohol = 1.17g water)
Although under normal circumstances this may not be an important consideration, when water supplies are restricted it is clearly advantageous that a large proportion of the energy requirement should be derived from fat or better still alcohol! On the other hand protein consumption should be kept low since urea produced from its metabolism requires water for its elimination via the kidneys.’ Biochemistry and Oral Biology, A S Cole and J E Eastoe 1983 p197
Memory refreshed; this is it in a nutshell. Alcohol is absorbed mainly from the stomach, where it travels to the liver via the blood stream to be metabolised (broken down). It’s this metabolisation process that produces the energy or ‘calories’. 1g of alcohol produces 7kcal. Relating this to other sources of energy 1g of fat produces 9kcal, 1g of protein or carbohydrate produces 4kcal. In practical terms 1 unit of alcohol is considered to have about 8g of alcohol. Half a pint of beer/larger/cider (1 unit) can vary from 85 to 205 kcal depending on the % of alcohol present.
Not to be outdone, I decided to give the books another try and managed to unearth this gem of information which may mean he’s on to something!
‘ … The metabolism of fat produces more water than either protein or carbohydrate
1g fat = 1.07g water
1g starch = 0.55g water
1g protein = 0.41g water
(1g alcohol = 1.17g water)
Although under normal circumstances this may not be an important consideration, when water supplies are restricted it is clearly advantageous that a large proportion of the energy requirement should be derived from fat or better still alcohol! On the other hand protein consumption should be kept low since urea produced from its metabolism requires water for its elimination via the kidneys.’ Biochemistry and Oral Biology, A S Cole and J E Eastoe 1983 p197
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