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5 Reasons Alcohol Makes You Fat

It’s not the carbs or sugar that go to your waistline, it's the booze.

Pixabay / creative commons
Down the hatch—and onto the hips.
Source: Pixabay / creative commons

Updated: May 29, 2020

Alcoholic beverages don’t have nutrition labels the way that other foods we eat do. The food police might rail against sugar, fats, and over-processing. But nutritionist Nicole Senior, allied with the University of Sydney that invented the glycemic index, points to alcohol as “the pink elephant in the room.”

At the very least, alcohol poses a fivefold challenge for those trying to watch their waistline.

Alcohol calories per gram

The first unpleasant fact is that at 7 calories per gram, alcohol contains nearly twice the number of calories as do carbohydrates (4 calories per gram) and proteins (4.2 calories per gram). On top of that we need to consider other components such as the carbs inherent in beer itself, the sugar contained in fruit juices and mixers, and the fat in the cream that goes into cocktails.

The second problem is one of storage. The body stores protein as muscle. It stores carbohydrate and fat as both glycogen in the liver and muscle, and as fat in adipose tissue, as many of us are all too well aware. (Glycogen is a multi-chain form of sugar.)

The body cannot store alcohol, however. Once ingested it must be burnt immediately. It takes precedence over any foods we eat with it or even what we consume over the course of a day. Worse, given alcohol’s high energy density, what food we do eat will count as surplus to our daily requirements. This surplus also gets turned into fat.

Alcohol as appetite stimulant

A third factor is that alcohol is a well-known appetite stimulant. For centuries physicians have prescribed the elderly, who often lose their appetites, a glass of wine before dinner. Enjoying an “aperitif” began as a French custom. The word means “to open,” and alcohol certainly opens us up as anyone can see from the widespread pairing of drinks with cocktail nuts, canapés, and hors d’oeuvres. A drink or two makes these high-calorie accompaniments go down the hatch with ease.

A fourth related factor is alcohol’s well-known effect as a central nervous system suppressant. In small doses, a drink or two preferentially suppresses inhibition more than other brain functions. This is why imbibers become more loquacious and uninhibited as a party wears on. Non-drinkers are quick to notice that conversation becomes louder and more boisterous within a short time. Inhibitions progressively fall away with each drink so that we find ourselves eating more of what’s before us or digging into ice cream, pastries, and calorie-dense treats that we’d normally forswear when not under the influence. As the alcohol dose increases, judgment increasingly goes out the window.

The food police routinely rail against sugar as a poison. But it isn’t at all. It is merely an example of “empty calories,” meaning calories that have no nutritive value. Alcohol, on the other hand, actually is a poison. In high enough doses are kept up over time it kills brain cells, peripheral nerves, muscle, kidney, liver, the retina, and just about all organs in the body. As with all poisons, the dose matters. Ask King Mithras, from whom we get the word mithridatic, a draught which bestows immunity to a given poison by ingesting gradually larger doses of it.

Alcohol metabolism can't be hurried

The final reason that alcohol easily makes us fatter is that it undergoes a rare form of metabolism called “zero-order kinetics.” Nearly all foodstuffs follow first-order kinetics. In physiologic terms, first-order kinetics means that you can speed up a given substance’s metabolism in the body’s furnace by piling on more of it in the way that shoveling more coal into a boiler makes the fire burn hotter. Alcohol is a notable exception to this rule. No matter how much you ingest — even if you chug from the bottle — nothing whatsoever can speed up the metabolism of alcohol. It burns at a steady rate of one ounce per hour. This is why coffee can’t sober up drunks. All you get is a wide-awake drunk.

This inability to speed up Mother Nature is the prime reason why the above factors are so powerful, and why their effects persist for a long time.

To sum up, most of the calories in drinks come from the alcohol more than the carbs or sugars they contain. Fake beers such as O’Doul’s, Clausthaler, and St. Pauli Girl that have an alcohol content of 0.1-1% are far better for your waistline and your inhibitions than are lite low-carb beers.

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More from Richard E. Cytowic M.D.
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