The calcium salt of D-glucaric acid, a compound found in small amounts in oranges, apples and cruciferous vegetables. It is metabolised to D-glucaro-1,4-lactone, an inhibitor of the enzyme beta-glucuronidase.
The whole commercial case for calcium D-glucarate is one enzyme. Beta-glucuronidase, produced by gut bacteria, cleaves the glucuronide conjugates the liver attaches to hormones and other compounds before excreting them, releasing the parent compound for reabsorption. Inhibiting it should in principle increase elimination of conjugated oestrogens. That mechanism is supported in rodents. In humans there is essentially nothing: no controlled trial has measured hormone levels, hormone-related symptoms or any clinical outcome after calcium D-glucarate supplementation. It is a supplement sold entirely on a plausible mechanism, and the marketing language around it is usually the kind this catalogue refuses to repeat.
Sold as
Capsule, Tablet
Standardised to
Milligrams of calcium D-glucarate — a product without this marker may not resemble what was studied.
Also known as
D-glucarate, Calcium glucarate, Saccharic acid salt
Regulation: Sold as a dietary supplement in the US with no pre-market efficacy review. It is frequently marketed with hormone-clearance claims that go substantially beyond the human evidence, which is close to non-existent.
What the research used
The amounts, forms and durations published trials of Calcium D-glucarate actually administered.
These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.
Studied for Common supplement use
500–1500 mg
Not enough
Capsule, daily or divided
What products contain. No human trial has established an effective dose, so this range reflects manufacturing convention rather than research.
This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.
When it was taken
Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.
None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.
🕐Any time
Not enough
No timing research exists. Divided dosing is sometimes suggested on the basis of the short half-life of the active lactone in rodents.
Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.
The evidence in depth
Best supported: Not enough
What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.
There is no human trial data on liver markers or hepatic conjugation with this supplement. Claims about supporting liver clearance are mechanistic speculation.
Not enough evidence. Not enough human research to say anything useful yet.
The claim that calcium D-glucarate lowers circulating oestrogen, and with it hormone-related symptoms, has not been tested in a controlled human trial. The evidence is rodent work and enzyme chemistry.
What may be going on: D-glucaro-1,4-lactone inhibits bacterial beta-glucuronidase, which would reduce reabsorption of conjugated compounds from the gut.
Not enough evidence. Not enough human research to say anything useful yet.
Randomised controlled trial · International journal of clinical pharmacology and therapeutics · 1997 · PMID 9021436
Deep research mode adds each paper’s own conclusion and stated limitations.
Things to know
Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.
Worth knowing
No human efficacy evidence at all
This is one of the clearest cases in the catalogue of a supplement sold on mechanism alone. There is no randomised trial of calcium D-glucarate in humans measuring hormone levels, symptoms or any clinical outcome.
Interaction
Could reduce the effect of drugs cleared by glucuronidation
Interacts withHormonal contraceptives, drugs cleared by glucuronidation
Many medicines are eliminated as glucuronide conjugates, and altering enterohepatic recirculation could in principle change their exposure. Hormonal contraceptives are the most commonly raised concern. No human interaction studies exist, so the risk is unquantified rather than absent.
Worth knowing
Contributes calcium
The salt supplies calcium, which counts toward total daily intake for anyone already taking calcium supplements or with a history of calcium-containing kidney stones.
Avoid
No data in pregnancy or breastfeeding
A supplement intended to alter hormone elimination, with no human data, should be avoided in pregnancy and while breastfeeding.
In the food catalogue
The whole-food form, where one exists. The evidence for a concentrated extract rarely transfers to the food, or the other way round — these are cross-links, not equivalents.