The wisdom of the green smoothie has been attacked. When one of my favorite health bloggers wrote How Green Smoothies Can Devastate Your Health, my head rang with questions. In fact, I felt it a bit fear-based.
Many of us, in an effort to get healthy or alkalinize, consume green smoothies regularly. The vast majority of people who suffer from calcium-oxalate kidney stones have never ever had a green smoothie. Some believe whatever they read, and now some are afraid of eating greens because they’ve heard of dangers of getting too much oxalic acid. Naturally I had to figure out if there was any truth to this for the greater majority of people or for us. We make green smoothies regularly and eat handfuls of greens right from the garden. You’d think our whole family would have kidney stones!
You can read the opposing view here: Why Green Smoothies Will NOT Devastate Your Health. After hours of reading and comparing scientific findings, though you can probably guess where I’ll come down, I’ve formed my opinion.
A Few Problems For the Very Few
When combined with calcium, oxalic acid produces calcium oxalate, which may form kidney and other types of stones. This occurs because calcium oxalate is relatively insoluble, so in some people it combines and hardens instead of harmlessly excreting as a waste product.
Individuals with kidney stones, rheumatoid arthritis, gout, or vulvodynia – a condition causing vagina pain linked to oxalate deposits – are advised to restrict foods high in oxalic acid or oxalates.
How Green Smoothies Can Devastate Your Health states: “Oxalate stones can show up in any body tissue. Oxalate crystals resembling shards of glass which become lodged in the heart cause tiny tears and damage to this vital muscle with every single contraction.
As an OR heart nurse I have never heard of this!
“A frequent location for oxalates to end up is skeletal muscle which will cause pain with even normal movement and make exercise nearly impossible. Dr. William Shaw, Director of The Great Plains Laboratory for Health, Nutrition and Metabolism who has studied oxalates extensively, is convinced that oxalate toxicity is a factor in fibromyalgia the pain of which can absolutely devastate a person’s life.”
The Murky Middle Ground
- Oxalic acid occurs naturally in plants, animals, and in humans.
- Less than 2% of people ever get kidney stones, and those people do suffer. They occur when crystalline masses form in the urine, and in 80 percent, those crystals are based on oxalate combined with calcium. Most of the folk I’ve known had them 50 years before green smoothies were even a thing and ate bacon and eggs, grits and fried potatoes most of their lives.
- If you had to really avoid oxalic acid that would be difficult. Foods high in oxalate (100–900 mg per serving) are: Spinach, wheat bran, pecans, tea, buckwheat, black pepper, beet greens, Swiss chard, endive, cocoa powder, kale, sweet potatoes, peanuts (and PB), cooked green beans, turnip greens, chocolate, most nuts, most berries (strawberries), and dried beans.
- Oxalic acid is reduced only 30-87% by steaming, boiling, or wilting the leaves of any of these vegetables for 5 to 8 minutes. Seems it won’t go away and is there for a reason? If worried, dump the leftover water, because oxalic acid leaches out of the leaves and into the surrounding liquid. (PubMed)
- Lists of foods high in oxalic acid vary greatly from source to source. Many foods are considered high in oxalic acid, but studies have not shown that the body readily absorbs their oxalate content. (source)
Let Wisdom Rule
1. Recently, it was thought that tea – due to its high oxalate content – increased kidney stone formation, but new research has shown it to have a preventive effect. It seems that green tea binds to calcium oxalate, creating flat crystals that break down more easily than other shapes.
2. All the foods high in antioxidants are also high in oxalic acid. Avoiding them is not necessary for most people and would be unwise.
- When cancer is diagnosed there is always a low level of oxalic acid in the blood.
- Every alternative cancer cure that is successful is filled with foods, herbs, grasses, and teas (such as Essiac tea) that are full of high amounts of oxalic acid.
- When radiation is given for cancer patients as a “just in case”, the number, time and power of each treatment will determine how completely oxalic acid in the blood is decomposed. The decomposition of the oxalic acid in the blood by radiation may so weaken the immune system so that one cannot fight off any viral or bacterial disease. Therefore, it is understandable that many cancer patients die from cancer related to viral pneumonia.” (source)
5. Leafy greens are the backbone for any continuous full-body detox or cleanse. They are alkalizing, and an alkaline body is better at battling bad bacteria, yeast and keeping cravings at bay.
6. Parsley and cilantro (coriander) bind heavy metals like mercury so they can be extracted from your body. They are also alkalizing and full of chlorophyll.
7. While spinach may not give you superhuman strength to fight like Popeye, spinach does an excellent job fighting anemia. Cooking increases its iron content.
Even if you could avoid these foods you would not want to!
Keep Making Your Green Smoothie…
Not all green leafy vegetables are high in oxalates. Highly nutritious kale is perfect for a green smoothie with only 2% of the oxalic acid content of an equal serving of spinach.
Other green vegetables that are lower in oxalates (and may be subbed to a green smoothie) include broccoli, cabbage, Romaine lettuce, bok choy, cucumber, and zucchini (Department of Nutrition at the Harvard School of Public Health).
Very mild low-oxalate Romaine lettuce and bok choy are so super-packed with vitamins, minerals, phytonutrients and fiber, I will be adding them in my routine green smoothie.
So cast off worry and fear! Everything we do has a problem if you look hard enough. Bad things in the water, bad things in the food, even breathing allows toxins into our bodies, but God created our bodies to heal themselves when we take advantage of the whole foods He gave us as gifts. The key is the word ‘whole’!
The Bible tells us that true medicine is leaves. The common name used for medicinal leaves is herbs. Ps.104:14 says that He has given us “herbs for the service of man”.
“And God said, “Behold, I have given you every plant yielding seed that is on the face of all the earth, and every tree with seed in its fruit. You shall have them for food.” ~Genesis 1:29
Those desiring to stay healthy do not need to stop our routine green smoothie or avoid dark leafy greens just because they are high in oxalates. The vast majority of credentialed scientists and health experts agree unless foods high in oxalates are consumed to excess.
For those who do need to reduce oxalates, here is a great FB group to follow.
I would love to hear your thoughts pro or con.
Thanks for reading!