Cloves contain compounds that interact with estrogen receptors, support bone density, and may improve ovarian function, making them uniquely relevant to female health beyond their reputation as a kitchen spice. The most active compound in cloves, eugenol, acts as an estrogen receptor antagonist, meaning it can block certain estrogen activity in the body. This has implications for everything from breast health to menstrual cycle regulation.
How Cloves Interact With Estrogen
Eugenol, the primary active compound in cloves, binds to estrogen receptor alpha, the same receptor that estrogen itself targets in breast tissue, the uterus, and the ovaries. But instead of activating the receptor, eugenol blocks it. This makes it what researchers call an estrogen receptor antagonist. In lab studies on human MCF-7 breast cancer cells, eugenol inhibited cell proliferation and triggered programmed cell death in estrogen-sensitive cells.
This doesn’t mean cloves act like hormone therapy or have a dramatic effect on your estrogen levels from normal dietary use. But it does mean the compounds in cloves can modulate how estrogen behaves at the cellular level, particularly in tissues that are highly responsive to estrogen. For women with estrogen-dominant conditions, this is a mechanism worth knowing about.
Effects on Ovarian Health and PCOS
Animal research on polycystic ovary syndrome (PCOS) has produced some of the most striking findings about cloves and female reproductive health. In a study on PCOS-model rats, a low dose of clove oil (30 mg/kg daily for 14 days) significantly improved ovarian structure. The number of healthy developing follicles nearly doubled compared to untreated PCOS animals, cystic follicles dropped dramatically, and the number of corpus luteum (the structure that forms after ovulation, confirming that ovulation actually occurred) increased from 1.6 to 6.8.
The improvement appeared to work through the hormonal feedback loop between the brain and ovaries, helping restore more normal levels of reproductive hormones. Clove treatment also reduced the rate of cell death in primary and developing follicles, a common problem in PCOS where oxidative stress damages eggs before they mature. Interestingly, these benefits only appeared at the lower dose. At double the dose (60 mg/kg), the protective effects disappeared entirely, and follicle counts looked nearly identical to untreated PCOS. This is a clear signal that more is not better when it comes to clove supplementation.
Bone Density Protection
Bone loss accelerates in women after menopause as estrogen levels decline, and cloves contain two things that work in favor of bone preservation. First, a single teaspoon of ground cloves provides 0.63 mg of manganese, a mineral directly involved in bone formation. Women need about 1.8 mg of manganese daily, so even modest use of cloves in cooking contributes meaningfully.
Second, eugenol itself appears to protect bone structure. In a study on diabetic rats (which experience accelerated bone loss similar to postmenopausal women), eugenol treatment improved key measures of bone quality, including the ratio of bone volume to total volume and the thickness of the spongy bone tissue inside the femur. Researchers attributed this to eugenol’s antioxidant activity, which reduced the oxidative damage that breaks down bone tissue. These results are from animal models and haven’t been confirmed in human clinical trials, but the combination of manganese content and eugenol’s bone-protective properties makes cloves a reasonable addition to a bone-health strategy.
Blood Sugar and Metabolic Effects
Blood sugar regulation matters for women at every stage, but especially during hormonal shifts like perimenopause, when insulin sensitivity often declines. A pilot study in human volunteers found that a water-soluble clove extract taken daily for 30 days reduced post-meal blood sugar by 21.5% in healthy participants and by 27.2% in prediabetic participants. Lab analysis showed the clove compounds increased glucose uptake by cells by as much as 63%, suggesting they improve how effectively the body responds to insulin.
These are notable reductions from a plant extract rather than a pharmaceutical. For women dealing with insulin resistance, whether from PCOS, prediabetes, or metabolic changes during midlife, cloves may offer a supplementary benefit alongside diet and exercise.
Antifungal Properties
Yeast infections caused by Candida albicans are one of the most common recurring infections in women. Clove essential oil inhibits the growth of Candida albicans at relatively low concentrations (a minimum inhibitory concentration of 2.5%). This antifungal activity comes primarily from eugenol, which disrupts the cell membranes of fungi. Clove oil is not a replacement for antifungal medication for an active infection, but its broad antifungal activity is one reason it appears in some natural hygiene products.
Antioxidant Capacity
Cloves rank at the top of the spice world for antioxidant power. On the ORAC scale developed by the USDA to measure antioxidant activity, cloves score over 10 million, far exceeding other commonly cited antioxidant foods like blueberries. This matters for women because oxidative stress plays a role in conditions that disproportionately affect female health: it damages developing egg cells, accelerates skin aging, contributes to bone loss, and drives chronic inflammation. You don’t need large quantities of cloves to benefit. Because the antioxidant compounds are so concentrated, even small amounts used regularly in food or tea deliver a meaningful dose.
Safe Amounts and Risks
The World Health Organization sets the acceptable daily intake of eugenol at 2.5 mg per kilogram of body weight. For a 60 kg (132 lb) woman, that’s 150 mg of eugenol per day. A teaspoon of ground cloves contains roughly 5 to 6 mg of eugenol, so normal culinary use falls well within safe limits. You would need to consume cloves in supplement form or use concentrated clove oil to approach the upper boundary.
Clove oil is where the real risk lies. Ingesting large amounts of undiluted clove oil (10 to 30 mL) has caused severe liver injury, with damage appearing 12 to 24 hours after ingestion. Documented cases involved rapid onset of confusion, seizures, and dangerously low blood sugar, followed by significant liver damage. These cases were extreme overdoses, mostly in young children, but they illustrate why clove essential oil should never be swallowed in quantity. At normal dietary doses, eugenol has not been linked to liver enzyme elevations or any clinically apparent liver injury.
The PCOS research also reinforces that dose matters in a practical way: the lower dose improved ovarian health while the higher dose provided no benefit at all. If you’re using cloves for health purposes, consistency at small amounts is a better approach than large doses.