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.