It's hard to find a woman wearing yoga pants who isn't carrying a Big Gulp-sized cup of blended fruits and vegetables. They're practically inseparable – kind of like Thor and his hammer – but there are plenty of men that seem willing to swill this stuff too.
They all put their heads on their pillows at night and sleep peacefully, believing that all that juice is helping them thwart a whole spectrum of diseases and ailments, along with making them slimmer with breath that smells like an Air Wick plug-in dispensing the clean scent of fresh-cut hay.
They probably shouldn't sleep so soundly, though. Juicing and plain old fruit juice carries a host of potential problems. Drinking too much of it or drinking it too frequently can make you pre-diabetic, fat or fatter, wipe out the microflora in your gut, and, according to new research, possibly increase your chances of dying by 24%. (1)
It's all because of the sugar they contain and, lest you think that sugar from pulverized fruits and vegetables is somehow better for you, realize this: All sugar, whether it's from fruit, honey, Coca-Cola, or high-fructose corn syrup (HFCS):
"Delivers the same sugars in the same ratios to the same tissue within the same timeframe to the same metabolic pathways." (2)
I know what you're thinking:
"How can honey be just as bad as HFCS? For that matter, how can HFCS be the same as sugar from fruits, regular corn syrup, or table sugar? That's certainly not what I've read."
The simple answer is that what you've read is a crock, like when your older brother swore to you that the movie "Ratatouille" was based on a true story.
The more complicated answer is that regular corn syrup doesn't have any fructose in it at all. It's 100% glucose. By that standard, ANY corn syrup that's manufactured to contain any fructose is automatically classified as HFCS.
Consider that the HFCS most commonly used in industry contains only 42% fructose, while the much-revered-by-granola-crunchers honey contains 49% fructose. (3) Even plain old table sugar is a 50/50 blend of glucose and fructose.
And yeah, fructose is metabolized differently and can more directly impact blood sugar than glucose in the short run, but the overall metabolic effects are the same as you get from any type of sugar. All of this begs the question, why then is HFCS so feared?
The problem originated with a 2004 study that correlated America's increasing fatness with the rise in HFCS production, but as we know, correlation doesn't always mean causation.
Hell, you could have made a similar case that America's fatness was in fact caused by decreased use of the 90's slang term, "Boo-Yah!" Again, correlation but not necessarily causation.
A 2014 review in the journal Diabetes Care tried to smack down the fructose myth by writing:
"The belief that sucrose is metabolized differently than HFCS is a myth. No study has shown any difference between the two... nor is there any difference in sweetness or caloric value." (4)
That means that all sugars, regardless of where they come from, can do equal amounts of harm, but juicing in particular poses a litany of unique problems.
When you Osterize your fruits, you obliterate all the fiber so that the microflora in your gut have little to munch on. They end up kicking tiny buckets and their bodies are loaded onto the turd train leaving for Porcelain City at 7 AM.
Not only that, but the carbs are so bladed up, so cut up into teeny-tiny pieces, that they can actually bypass a lot of the digestive process. That means insulin surges. Big ones. If the surges were tsunamis, your uncle's goat farm in Nebraska would be washed away.
Much of that huge bolus of sugar gets hand delivered to the liver, where it's converted into fatty acids and then sent to your thighs, butt, waist, or wherever else you don't want it, for storage.
This grinding up also affects the volume of whatever fruit's juice you're swilling. Un-pulverized fruits and vegetables take up a lot of space and push against the walls of your stomach, which tells the brain to lay off with any more food. Not so much with juices.
You might be able to eat a few whole kiwis, but you can probably drink a considerably larger number of them. More fruit equals more calories. More fruit equals more sugar. And more sugar is, as you know, a problem.
You're probably still clinging to the notion that the sugar in juices can't be as bad as those in sugar-sweetened beverages like Mountain Dew, Coco-Cola, or Red Bull. They are.
In terms of long-term effects on diabetes and overall mortality, there's no difference between the two categories, at least if you believe the results of the big study I mentioned above.
Researchers from Emory University, writing in JAMA, detailed the results of a study of 13,400 US adults over a mean of 6 years. (1) They found that each additional 12-ounce serving of juice that adults drank each day was associated with a 24% increase in overall mortality, especially from cancer and heart problems, but certainly also from diabetes.
Of course, there might be other unrealized factors at play to cause such a large uptick in deaths, but regardless, it doesn't take too much of a leap of faith to assume the sugar in the juices played at least some significant role.
Oddly, you'd think the various polyphenols, antioxidants, vitamins, and minerals would somehow offset some of this dying, but sugar might just be too formidable a foe.
Clearly, we all need to reduce our intake of sugar, if we haven't already done so – especially the sugars that are hiding in plain sight like grocery store juices and the ones you get from little huts with mock palm tree thatching on top. Instead, go with whole produce.
If you're not willing to give up your juices because that's practically your only source of fruits and vegetables, at least opt for blended juices that contain more vegetables than fruit – more ground up leaves and stems than the sweet, pulpy stuff that carries the seeds.
Granted, they might taste like something that was filtered through a fat, sweaty guy's yoga pants, but you'll be better off.
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