Hey folks!
A few days ago someone sent me this paper about a woman who experienced full kidney failure. How? From a “green smoothie cleanse.”
Sounds crazy, huh?
Folks love the idea of “cleanses” and all manner of pseudoscience gets wrapped into these things.
On one hand it’s kinda compelling: Eat LOTS of greens! A quick fix to get back on track! Clean your body of “toxins!” If a little kale is good, a couple pounds is better, right?!
Well…we can overdo just about anything, and greens are no exception.
How can something as nutritious as dark leafy greens do you wrong? In order to protect themselves from predators (read: birds, insects, other creatures), plants contain a host of anti-predation chemicals. One form of these chemicals are called oxalates. There are critters out there that can handle a high oxalate intake but they typically have both genetic adaptations as well as help from symbiotic bacteria to degrade these chemicals.
For example, the Hadza appear to harbor oxalate degrading bacteria in their guts. But this is not a common feature in most folks living a Westernized lifestyle. This means that consuming heroic amounts of greens or other oxalate rich foods could score one a long series of visits to the local dialysis center.
I’ve never been a huge fan of shakes and smoothies (if you poke around the site you won’t find ads for protein powder or much in the way of smoothie recipes). I’m kinda crazy in that I think folks tend to do best when they “chew” their food.
Like I said, I’m crazy this way.
Why? Well, I’ve noticed it’s easy for folks to overeat shakes and smoothies (they do not really satisfy you for all that long), which leads to this potential to consume a toxic dose of oxalates or other anti-predation chemicals (if you thrive on shakes and smoothies, fantastic! I’m still not a fan but by all means, keep doing what is working for YOU).
I know some popular folks recommend nutrient dense shakes with a host of greens and other goodies in them. I’d just recommend you keep the amounts consumed limited to what you actually COULD chew in a meal. Some folks still manage to ingest a toxic level of oxalates by eating them (steaming, boiling, soups, etc.) this is rare, but it happens.
I know it’s crazy to have a cautionary tale about ingesting vegetables when so many people eat too little of this stuff, but I just want to provide some context for folks who could be swayed that if a little is good, a lot is better.
Check out the article in full here.
Good point..Chewing coats food with saliva, activates the brain and digestive juices in the stomach for optimal digestion…On a Paul Pitchford note in Healing with Whole Foods, we loose the energetics of the food when it is processed into a powder are by a blender. Whole foods that we masticate with our teeth and savor with our tongue are of a higher caliber and amplitude than powdered or blended food particles.
sorry for the typo!
Green smoothies are awesome, this is just like that other woman who died after drinking too much water. Crazy people do all sorts of crazy stuff, it’s certainly not kales fault…
I’ve currently settled on a small morning smoothie for convenience as I try out the restricted eating window with a bias to daylight hours, which means a decent breakfast, and early dinner. But I always pair it with quality animal products, be it some pastured bacon, leftover chicken thighs, smoked (wild caught) salmon, or even salmon roe if in a pinch and feeling like it.
My smoothie is cup of kefir, large handful of mixed berries, small handful of spinach, squeeze of lime or lemon juice, chunk of ginger, and a brazil nut or two. Sometime throw in half an avocado. Delicious and nutrient packed.
This also may sound strange to some, but it works for me, but what I do is I try (don’t get zealous about this stiff!) have a bite of every ingredient I am putting into my smoothie, which is just grabbing a berry, having a swig of kefir, etc, as I am prepping/washing.
Not really a smoothie fan but the fact that she had had a gastric bypass might have had something to do with it. I guess a normal functioning intestine possibly would help take away some of the toxic load of the oxalates from the kidneys. Hey, Robb did you see the paper that recommended a ketogenic diet for patients about to undergo bariatric surgery https://link.springer.com/epdf/10.1007/s11695-018-3145-8. It’s ironic and maddening at first thought, but maybe a sneaky way of showing the light to some of these folks and get them to realize that diet can still work.
Matt! yes, the bariatric surgery def made this a trainwreck, but there are case reports in folks without the procedure. Have not seen that paper, thanks!
Bariatric patients are more susceptible to oxalate crystal formation because of fat malabsorption. Excess free fatty acids in the gut cause too much oxalic acid to be reabsorbed back into the body instead of being excreted in the gut. (It has to do with calcium binding to the FFAs…) So you can totally see the picture – a post-bypass patient with weight regain, desperately trying to get back on track, reading about the “miracle weight loss” from a green smoothie cleanse instead ends up with kidney stones or even full-blown kidney failure.
too true, although pubmed does have it’s share of stories like this from non-bariatric patient examples. Harder to overdo, but folks can impress in a variety of ways!
A very helpful post, Robb. I went big on green shakes for a short while, then shifted to more fruit and the odd green leaf of two and finally came off them except occasionally. Meaning a couple of times a week max. All this in a matter of weeks. Why? Because following through on your food life-style, which I had already done, I was much more aware of the impact of food itself, in whatever form, on my body and mind. Becoming aware, I learned to trust my instinct and physical feelings. So not very scientific really, but I’m happy to read a post that affirms where I’m at with shakes – whether green, pale pink or just plain murky!!
Not all greens contain a lot of oxalates — spinach, very high levels; kale, very low. Also, eating high oxalate foods together with high calcium foods will bind some of the oxalate to the calcium before it gets absorbed into your blood stream. Useful information for calcium oxalate kidney stone formers — they need to maintain a low oxalate diet.
I think the green smoothies are a great idea! And if you drink them from time to time, then it will be a great cleanse to the body!
Great content! Is so wonderful the elements that the nature bring for us.