Oxalates
Tiny crystals, big problems. Oxalates are plant defense compounds that form sharp crystals in your body—causing kidney stones, joint pain, and mysterious symptoms.
What Are Oxalates?
Plant Defense
Oxalic acid is produced by plants to deter animals from eating them. Found in high concentrations in spinach, almonds, beets, chocolate, and rhubarb. When you eat these foods, you're ingesting the plant's chemical weapon.
Crystal Formation
Oxalates bind to calcium, forming calcium oxalate crystals. These sharp, needle-like structures can deposit anywhere—kidneys, joints, eyes, thyroid, skin, brain. They cause mechanical damage and trigger inflammation.
⚠️ High Oxalate Foods to Limit
Very High (100+ mg)
- • Spinach
- • Rhubarb
- • Almonds
- • Beet greens
- • Swiss chard
High (50-100 mg)
- • Beets
- • Cocoa/chocolate
- • Sweet potatoes
- • Potato (with skin)
- • Peanuts
Moderate (25-50 mg)
- • Black tea
- • Berries
- • Carrots
- • Celery
- • Beans
Low (<25 mg)
- • Meat/fish
- • Eggs
- • Cheese
- • Cauliflower
- • Cabbage
Symptoms of Oxalate Overload
Pain
- • Joint pain (any joint)
- • Muscle aches
- • Burning feet
- • Fibromyalgia-like symptoms
Kidney/Urinary
- • Kidney stones (80% are oxalate)
- • Frequent urination
- • Painful urination
- • Cloudy urine
Neurological
- • Brain fog
- • Fatigue
- • Mood issues
- • Sleep problems
Eye
- • Gritty eyes
- • Eye pain
- • Sandy sensation
Skin
- • Rashes
- • Hives
- • Vulvodynia
Digestive
- • Gut inflammation
- • Abdominal pain
- • GI issues
Why Some People Are More Affected
AGXT Enzyme Issues
The AGXT enzyme (requires B6) converts glyoxylate to glycine instead of oxalate. B6 deficiency or genetic variants → more endogenous oxalate production.
Lost Gut Bacteria
Oxalobacter formigenes degrades oxalates in the gut. Antibiotics kill it. Without this bacteria, more oxalates are absorbed into blood.
Leaky Gut
Intestinal permeability allows more oxalates through gut barrier. Heal the gut → reduce oxalate absorption.
Low Calcium Diet
Calcium binds oxalates in the gut. Low calcium = more free oxalate absorbed. Eat calcium WITH oxalate foods to bind them.
✅ Managing Oxalate Sensitivity
Reduce Slowly
Don't go low-oxalate overnight. Rapid reduction causes "oxalate dumping"—stored crystals release, causing flares.
Calcium with Meals
Take calcium (citrate) with oxalate-containing meals. Binds oxalates in gut before absorption.
Vitamin B6 (P5P)
Supports AGXT enzyme. Reduces endogenous oxalate production. Use P5P form for better absorption.
Magnesium
Inhibits oxalate crystal formation. Glycinate or citrate forms are helpful.
Stay Hydrated
Dilute urine oxalate concentration. Add citrate (lemon juice) to water—citrate inhibits crystal formation.
Heal the Gut
Reduce intestinal permeability. Restore healthy gut bacteria including Oxalobacter.
⚠️ Oxalate Dumping
When you suddenly reduce oxalate intake, stored crystals begin to mobilize. This can temporarily worsen symptoms—a phenomenon called "oxalate dumping."
Dumping Symptoms
- • Sandy/gritty urine or stool
- • Increased pain
- • Skin rashes or bumps
- • Cloudy/foul urine
- • Mood changes
How to Manage
- • Reduce oxalates GRADUALLY over weeks/months
- • If dumping is severe, temporarily increase oxalate
- • Support with calcium, B6, magnesium
- • Stay hydrated with citrate water
Metabolic Connections
Calcium
Binds oxalates in gut, preventing absorption
Magnesium
Inhibits oxalate crystal formation in kidneys
Vitamin B6
Reduces endogenous oxalate production via AGXT
Gut Health
Oxalobacter formigenes degrades dietary oxalates
Inflammation
Oxalate crystals trigger inflammatory response
Iron
Oxalates block iron absorption