Detoxing and green smoothies are trendier than ever but some people are claiming that the diet can sabotage your health due to the fact that it contains high oxalate foods.
People turn to detoxing because it can help you control your weight, increase energy, boost your immune system, and improves skin problems but is it possible that it can cause more harm than good?
A detox diet tends to be high in oxalate foods which can cause health problems for some people if they are eaten in excess or they suffer oxalate sensitivity. In this article I will cover the possible damaging effects of oxalate and how to identify if you have an oxalate sensitivity or overload.
What are Oxalates?
They are salts of oxalic acid which are found in many plants as a product of their metabolism. They are also made by fungal infections and human metabolism. Under normal circumstances when you eat foods with oxalates they bind to minerals like calcium during digestion in the intestines and leave the body in the stool. The rest that doesn’t bind to minerals travels as a waste product to the kidneys and leaves the body in the urine.
The more magnesium, calcium and potassium you have in the diet the more the oxalates you eat will be bound in the intestines and excreted in the stool instead of being absorbed into the blood to be excreted by the kidneys. Having enough magnesium in the blood reduces the incidence of calcium-oxalate stone formation in the kidneys.
High Oxalate Foods
- Swiss chard
- Sweet Potatoes
- Cocoa Powder
- Baked potatoes with skin
- Wheat germ and bran
- Cocoa, chocolate
- Black tea, green tea
Related reading: The Detoxing Health Benefits of Leafy Greens
Vitamin C & Oxalate
If you’ve done any research into oxalates you’ve probably come across the suggestion that high doses of vitamin C can be converted to oxalates and increase the risk of kidney stones. In light of the fact that many people are taking high doses of Vitamin C to help prevent Covid-19 you may have concerns.
Research papers on this are contradictory but the Orthomolecular Medicine News Service states :
ascorbate (vitamin c) in low or high doses generally does not cause significant increase in urinary oxalate. ….. and ascorbate tends to prevent formation of calcium oxalate kidney stones.
As you can see from the list of high oxalate foods if you drink a lot of green smoothies crammed with spinach, kale or chard you would be drinking a high oxalate smoothie.
According to William Shaw PhD, founder of Great Plains Laboratory and creator of the organic acid test,
a person who consumes a green smoothie with 2 cups of spinach leaves is consuming about 150 times the average daily oxalate intake.
Each person reacts differently to high amounts of oxalate and some people are more prone to developing oxalate issues than others. This sensitivity can be determined by your genes or your gut bacteria.
Some of the oxalates we eat are broken down by bacteria in the gut before it can bind to minerals. One of these bacteria, Oxalobacter formigenes , breaks it down to use it as an energy source which reduces the amount of oxalate your body absorbs. This bacteria can also induce colonic secretion of oxalate which helps reduce our total oxalate load even further!
Some people don’t have much of this bacteria in their guts. This happens due to the high consumption of antibiotics, inflammatory bowel disease, SIBO (small intestine bacterial overgrowth) or a gut dysfunction, for example, after gastric bypass surgery or any medical procedure that alters the gut.
Related reading: Healthy Gut Bacteria : How to Restore them & Detoxify
Other beneficial bacteria have also been shown to reduce oxalic acid and include Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium breve, and Bifidobacterium lactis. They are available as probiotic supplements.
The Damaging Effects of Oxalate
Oxalate works as a calcium storage mechanism for plants but it can be toxic for humans in high amounts. Due to the fact that it binds to other minerals, it can affect the mineral absorption of the body especially when it is combined with fiber. The calcium in vegetables like spinach is useless because it is all tied up in oxalate and your body won’t absorb it.
When we combine oxalate sensitivity with a high-oxalate diet the result will likely be oxalate accumulation. When oxalate grabs calcium it forms calcium oxalate which is usually present in the urinary tract in small amounts that are harmless.
The problem comes when they bind to form crystals and build up into bigger crystals. As they begin to accumulate they deposit into different parts of the body. These crystals can lead to the formation of kidney stones which can cause severe pain, nausea, and blood in the urine.
Due to their sharp structure calcium oxalate crystals can cause damage to tissues. They can accumulate in your muscles as well as joints and cause pain, inflammation, or fibromyalgia. A doctor in England found relief from fibromyalgia when she cut high oxalate foods from her diet.
They can also form in the skin, eyes, thyroid gland, blood vessels, lungs, bladder and even the brain where they may cause neurological symptoms and affect cognitive functions like memory, learning, and concentration. They can worsen the symptoms of mysterious vulva pain and carpal tunnel syndrome.
Having a leaky gut can increase the absorption of oxalate which will exacerbate the gut dysfunction creating a destructive cycle. It can deplete vitamin B6 and the deficiency increases the internal production of oxalate and can alter the metabolism of biotin.
Signs of Oxalate Toxicity
Pay attention to these signs that may indicate an oxalate toxicity:
- Muscle & joint pain
- Fatigue and a lack of energy
- Depression and anxiety
- Frequent urination and bladder pain (interstitial cystitis)
- Intestinal pain, SIBO
- Burning or tingling in hands or feet
- Persistent or recurring fungal infection like candida .
- Thyroid condition
- Kidney stones; although there are different types of kidney stones, oxalate made up to 80% of them.
Histamine & Salicylate Sensitivity
I have to point out that high oxalate foods are also rich in histamine and salicylate. These two compounds can also be a problem for some people. If you feel better when you reduce dietary oxalate it may be that you had an intolerance to histamine or salicylates. The three often go together.
The underlying cause usually lies in the gut but salicylate sensitivity can be due to impaired Phase 1 & 2 liver detox pathways. As well as lowering these substances in the diet the best approach to find out what is going on in your gut and liver.
Testing for Oxalate
One test that can be done to see if you have an oxalate problem is to do an organic acid test. This is a urine test that tests for other metabolites besides oxalates. It has to be interpreted in conjunction with your symptoms.
If you decide that you may have an oxalate problem you should reduce high oxalate foods very gradually to avoid dumping symptoms. This is a process that happens when you start to abruptly reduce the amount of oxalate from your diet and your body starts to release the storage oxalate from the tissues.
The “oxalate dumping” can cause joint pain, fatigue, back pain, pain in the gut, skin eruptions, and insomnia. For this reason, you should slowly cut out oxalate from your diet instead of doing it quickly.
Vitamin B6 has been shown to reduce oxalate production because it is a cofactor for an enzyme that degrades oxalate in the body. Vitamin E, selenium, and arginine have been shown to reduce oxalate damage so may be worth taking.
Increasing Omega 3 in the diet may help to reduce oxalate problems. Increasing water intake can help to eliminate oxalates.
A probiotic supplement containing Lactobacillus acidophilus and Bifidobacterium lactis could help as they have enzymes that degrade oxalate.
Should you avoid drinking green smoothies?
Detoxing and drinking green smoothies is a practice that has been recommended by Naturopaths and other health practitioners for years without any problems. According to Thomas Lodi MD, drinking green juices and smoothies is not only healthy but actually protective against kidney stones. He states that 80% – 90% of oxalate found in the body are produced in the liver as a result of carbohydrate metabolism.
He further states that in 15 years of putting cancer patients on a dietary regime that included drinking 1 – 2 quarts a day of green vegetables juices and smoothies and eating abundant amounts of green leafy vegetables, fruits, nuts and seeds he has not seen one case of oxalate or kidney stones. Countless other health practitioners have found the same thing in a multitude of centers.
If you already regularly drink green smoothies as part of a detox diet or are thinking of starting one and are worried about oxalate issues it’s a good idea to rotate your greens. Instead of using a lot of high oxalate foods in smoothies include low-oxalate options such as mustard greens, watercress and various types of lettuce. Also, you might consider supplementing with oxalate-degrading probiotics such as Lactobacilli and Bifidobacteria.