Oxalates In Spinach and Other Leafy Greens: Can Oxalic Acid In Green Smoothies Devastate Your Health?

Whenever you hear someone say one thing about health and nutrition, you can always find someone else saying an exact opposite. No wonder most people are confused about what to eat! It’s hard to make sense from all that noise.

For example, Is there a hidden danger lurking in green smoothies? There have been articles appearing on the Internet recently about dangers of oxalic acid and how it can have devastating effect on your health.

The authors’ advice has been to limit or completely avoid greens and stop making green smoothies! (What should we be eating instead? Butter, milk, meat and sausages – according to one author, whom I will not cite here).

Even though 2/3 of our population is currently considered obese; diabetes, high blood pressure, cancer and other ailments reached epidemic proportions; as people load up on high fructose, genetically modified corn syrup-filled sodas, french fries and fried chicken, pizza and super-sized meals…we need to limit green smoothies as they can “devastate” your health?

Wow, really??

The incidence of kidney stones is high in the US. However, it’s extremely unlikely that greens are the reason why we have lots of kidney stones, since most Americans eat very little greens.

can green smoothies devastate your health with oxalates?

It is estimated that about a million people in the United States are treated for kidney stones each year. About 80% of kidney stones formed by adults in the U.S. are calcium oxalate stones – surely these people aren’t all obsessive  green smoothie drinkers (or even spinach-salad-fanatics, for that matter).

Most of the foods that contain oxalates are powerful healing superfoods that can have a profound POSITIVE effect on your health and well-being, and should not be eliminated from the diet!

There is plenty of research that confirms the benefits of leafy greens, fruits and vegetables. A diet rich in alkaline foods (vegetables, fruit) is associated with a lower risk of stone formation, as well as lowered risk for most chronic diseases.

These are the  natural foods for humans – foods that our bodies have been designed to thrive on.

Instead of limiting greens, how about eliminating the true contributors to kidney stones (as well as obesity, diabetes, high blood pressure, and cancer) – for optimal health:

Soft drinks
Animal proteins
Bad fats
Salty foods (or any refined salt)
Coffee, tea and alcoholic beverages

How come no one is screaming about the dangers of consuming excessive animal protein, sugar or sugar substitutes?  Is it because they are safe? Or perhaps there is too much money at stake, with big industries protecting their profits?

Multiple studies in different countries have demonstrated that the over-consumption of animal protein is a major risk factor in kidney stones formation.  Sodas and other highly processed high-fat, high-sugar foods have been implicated in obesity and diabetes epidemic.  Yet, we see them everywhere around us – advertised on TV, online, and even in school cafeterias.

Noone is campaigning for more spinach or broccoli.

And now spinach is being under attack, accused of causing serious health consequences.

So, What About Oxalix Acid

Oxalic acid (also referred to as oxalates) is found in many foods, including spinach, swiss chard, strawberries, soy, almonds, and many other foods. Oxalate content of a single food group varies based on the time of year, the type of soil it is grown in and a host of other factors specific to the growing conditions of the plant.

Our bodies produce oxalic acid, often synthesizing other substances such as vitamin C into oxalic acid, so whether you eat foods that contain it or not, your body maintains a naturally-occurring level of oxalic acid.

Oxalic acid has been shown to bind with calcium (and magnesium, iron, sodium and potassium) in the intestine, thus interfering with the absorption of these. Typically, foods that have high oxalic acid also have high calcium, so they buffer each other.

Oxalic acid seems to be a controversial subject among nutritionists and health experts. Finding a clear answer regarding the potential safety or dangers of this substance can make your head spin.  Victoria Boutenko did an excellent job addressing this issue, so if you want detailed research, read this blog post.

If You Are Concerned About Oxalates

Even though oxalic acid is not believed to be a health concern for most people, it can be difficult to digest for a certain percentage of the population. The most common cause of a toxic build-up of oxalate in the system is poor intestinal health or function, including an unhealthy of unbalanced intestinal flora (often from overuse of antibiotics), irritable bowel syndrome, leaky gut, celiac disease or fat malabsorption.

If you have a history of kidney stones or a medical condition that is complicated by the consumption of oxalate-rich foods, consult your doctor or health practitioner for advice.

In general, replacing oxalate-rich greens such as spinach and parsley with Romaine lettuce or other lettuces will lower exposure, but also lower overall nutrient density of your smoothies. Mixing spinach with lower-level oxalate-containing greens will help lower oxalate content.

Beet leaves, purslane leaves, spinach, swiss chard (leaves & stalks), rhubarb, parsley, amaranth leaves, sorrel.

Dandelion greens, most fruits, bok choy, kale, watercress, escarole, mustard greens, turnip greens, broccoli, tomatoes, asparagus, and cabbage.

Rotating greens and other foods regularly is important as it helps to limit over-consumption of any one nutrient (or toxin) and provides more health-promoting benefits.

Also, listen to your body and learn to pick up on the subtle cues it’s giving you.

Green Smoothies with Low Oxalic Acid Content

For those of you, who would rather not consume high amount of oxalic acid, here are some recipes of green smoothies with very low oxalic acid content (from Victoria’s blog).

Sweet Sprouts
1 bunch green leaf lettuce
1 handful alfalfa sprouts
2 ripe apples, peeled, pits and stems removed
2 ripe bananas, peeled
2-3 cups water
Blend well.
Yields 2 quarts
oxalic acid foods
Romaine Green Smoothie
1 head romaine lettuce
2 ripe apples, peeled, pits and stems removed
1 ripe mango, peeled, pit removed
3 cups water
Yields 2 quarts

Green Freshness
1 head red leaf lettuce
1 ripe cantaloupe, peeled, seeds removed
1 cup fresh apple juice
2 cups water
Yields 2 quarts

Lettuce Drink to Your Health
1 handful red leaf lettuce
1 handful green leaf lettuce
1 cup cherries, pits removed
2 ripe bananas, peeled
2 cups water
Yields 2 quarts

Enjoy Your Green Smoothies!

Green smoothies provide tons of nutrients that our bodies need to function optimally, many of these from the potent antioxidants found in spinach, kale, chard, watercress, blueberries, strawberries, carrots, oranges, peppers, tomatoes and other – all of which have oxalic acid.

I certainly wouldn’t avoid spinach or other leafy greens because of the oxalic acid effect. Spinach has a lot to offer nutritionally: it’s an excellent source of folic acid, potassium and magnesium, as well as vitamin K, carotenes, vitamin C and lutein, important for healthy eyes.

So go ahead and enjoy your green smoothies and the health benefits they provide!

More reading on this issue:

Oxalic Acid and Green Smoothies 

Can green smoothies “DEVASTATE” your health? 

More Meat, More Disease