In this video, we will learn about oxalates, discover the foods to avoid, and develop a plan to counter oxalates in the body.
Oxalates are naturally occurring compounds found in several plants, as a defence mechanism. Plants produce oxalates to deter herbivores and pests. Oxalates bind with calcium to form sharp needle-like crystals in the body that can cause irritation when ingested. Most people get between 200 and 300 milligrams of oxalates daily. If you're at risk of kidney stones, less than 100mg a day is recommended. Oxalates are also naturally created in the human body as a waste product. The body's kidneys typically filter oxalates, which are then eliminated in urine or stools. Oxalates can also cause cell death in your kidneys epithelial cells.
Hyperoxaluria is a condition in which you have too much oxalate in your urine. High levels of oxalate are toxic because it cannot be broken down by the body. Calcium oxalate accumulates in the kidneys which may cause kidney stones.
There are two kinds of oxalate in foods – soluble oxalate and insoluble oxalate. The insoluble oxalate binds with calcium, so the calcium and the oxalate are not absorbed. In food, oxalic acid is typically found as either sodium or potassium oxalate, which are water soluble, or calcium oxalate, which is insoluble.
Oxalates and Bone Health.
Excessive oxalate consumption can interfere with calcium absorption, which is crucial for maintaining healthy bones. When oxalates bind with calcium in the digestive tract, it forms insoluble calcium oxalate crystals, which reduces the amount of available calcium for absorption.
Feeling tired? Oxalates harm your mitochondrial health.
The tiny mitochondria in our cells produce chemical energy. This energy is stored in a small molecule called ATP. Oxalates are a mitochondrial toxin that inhibits this cellular energy process. High concentrations of oxalate can lower the flux through the citric acid cycle by up to 48%. High oxalate levels sap your energy and cause blood sugar problems.
Oxalates and food
Vegetarians who consume greater amounts of vegetables will have a higher intake of oxalates, which may reduce calcium availability. Please bare in mind that some oxalate-rich foods are also very nutrient-rich and shouldn't be avoided.
It's almost impossible to avoid oxalates in plant-based foods. But what plants are high in oxalates?
Fruits tend to be low in oxalates.
Here we can see some fruits with higher oxalate content. With rhubarb being the oxalate king!
Several plants are high in oxalates
Spinach stands out for its high oxalate content. Potatoes are high too, but most oxalates are found in the skins and can be reduced by soaking and boiling.
Some grains and seeds are high in oxalates.
Whole grain and bran products stand out for high oxalate content. All types of nut, vegetable, and seed oils are considered very high in oxalates, with 1 tablespoon containing 14 or more milligrams of oxalate. Studies have found that seed oils promote the production of oxalate in the body (called the glyoxalate pathway). When PUFFA seed oils oxidise in the body, they produce glyoxylate from glyoxal. Here are some values for seeds.
Some nuts are high in oxalates.
In terms of nuts, the worst offender is almonds, including almond nuts and flour. Almonds hold about 216-305mg of gut-soluble oxalate per 100g.
Countering oxalates
- Avoid see oils.
- Food preparation and cooking have a big effect on oxalate levels.
- Drinking plenty of water helps (remember to increase your electrolytes too).
- Eating calcium-rich foods, such as quality dairy, will add to your body's calcium pool. Oxalates bind with calcium in the colon, neutralising their impact on our health. Pair high oxalate foods with calcium-rich foods. Calcium supplements should be avoided as they can contribute to soft tissue hardening and an increased CAC score.
- Soaking high oxalate foods with calcium salts will reduce their oxalate levels. This study from 2017 showed a dramatic drop in spinach oxalate levels when the spinach is soaked in a calcium chloride solution. The water can then be drained. The optimal amount is around half a gram for every 100g of spinach. This also works with almonds.
- Pumpkin seeds lowered calcium-oxalate crystal occurrence. They also provide high phosphorus levels and lower the risk of bladder-stone disease.
- Potassium citrate increases urine citrate and urine pH, this helps to capture oxalates. Citrate binds calcium, reducing the amount of calcium available to bind with oxalate. It can also help dissolve existing stones. Higher dietary potassium intake would decrease urinary excretion of calcium, thus potentially protecting against stone formation. So switching to a low sodium salt or eating potassium-rich foods would really help.
- Don't drink plant-based milk.
To summarise, oxalates can cause serious kidney problems and also affect mitochondrial health. It's wise to sensibly restrict oxalates and to consume quality dairy
Rhubarb (1 cup) 1293mg.
Avocados (1 fruit) 19mg.
Dates (1 date) 24mg.
Grapefruit (1 fruit) 24mg.
Kiwi (1 fruit) 16mg.
Orange (1 fruit) 29mg.
Raspberries (1 cup) 48mg - blackberries only have 4mg.
Pomegranate (1 fruit) 140mg.
Rice bran (1 cup) 281mg.
Bran flakes cereal (I00g) 393mg.
Wheat bran (100g) 457mg.
Oatmeal (100g) 100mg.
Chia seeds (100g) 1400mg.
Soy foods (100g) 70mg.
Soy milk (1 cup) 10-70mg.
Tofu (100g)
Sweet potato (1 medium) 316mg.
Potato (1 medium) 97mg mainly in the skin.
Brown rice (1 cup cooked) 24mg.
Baked beans (1 cup) 150mg.
Weetabix (100g) 90mg
Swiss chard (1 cup) 1200mg.
Spinach (1 cup) 980mg.
Beets (1 cup) 1000mg.
Sweet potato (1 medium) 316mg.
Potato (1 medium) 97mg mainly in the skin.
Tea (1 teabag) 5mg.
Parsley (10g) 170mg.
Almonds (100g) 400mg.
Almond milk (1 cup) 25-70mg.
Almond flour (1 cup) 800mg.
Peanuts (1 cup) 190mg.
Cashew nuts (1 cup) 260mg.
Pine nuts (100g) 581mg.
https://core.ac.uk/download/pdf/80828058.pdf
https://pubmed.ncbi.nlm.nih.gov/3799495/
https://www.gdx.net/core/support-guides/organic-acids-support-guide.pdf