What Is Red Clover?

Red clover (Trifolium pratense) is a wild herb that belongs to the legume family, along with beans and peas. It's often promoted as a remedy for menopause symptoms, bone loss, and high cholesterol. This is due to plant chemicals called isoflavones, which may have some estrogen-like activity. However, the research into red clover's benefits is often lacking or inconsistent.

This article explains red clover's potential benefits, the possible side effects and interactions, and why (like all supplements) consumers should research it carefully.

Uses of Red Clover

There are several studies assessing red clover benefits for the following potential uses.

Menopausal Symptoms

Estrogen levels decline during the transition to menopause and it's believed that the estrogen-like qualities of isoflavones might help reduce menopause symptoms, such as hot flashes and night sweats.

So far studies on red clover for symptoms of menopause have been mixed. Several studies of a proprietary extract of red clover isoflavones suggest that it may significantly reduce hot flashes. Other studies show no effect.

A 2021 systematic review and meta-analysis (collection of studies) concluded that red clover isoflavone extract reduced the number of hot flashes per day. However, more well-designed studies are still needed.

Bone Health and Osteoporosis

Osteoporosis is a bone disease that develops when bone density and bone mass decrease. The risk of osteoporosis increases with age and particularly during menopause as estrogen levels drop.

In a small study of individuals in menopause, red clover extract positively affected bone health. Bone mineral density (BMD) only decreased in individuals taking the placebo (a substance with no medication). BMD measures your bones' strength and thickness (density or mass).

While this study shows promise, large and long-term studies are still needed.

High Cholesterol

Some preliminary research suggests that red clover may offer some benefits for those with high cholesterol.

A 2018 systemic review and meta-analysis found that people in menopause or transitioning into menopause who took red clover for four months to one year showed a significant increase in high-density lipoprotein (HDL), or good cholesterol, and a decrease in total and low-density lipoprotein (LDL), or bad cholesterol.

However, an earlier meta-analysis on isoflavones published in 2013 found that they didn't seem to significantly affect LDL, HDL, or total cholesterol. This review did find slightly lowered triglyceride levels compared to placebo.

Further study is warranted.

Heart Health

High LDL increases your risk for heart attack and stroke. Based on red clover's potential benefits for LDL, it may offer some heart health benefits. Although, the research is still unclear.

For example, a small study in 147 postmenopausal women showed a 12% decrease in LDL in those who took 50 milligrams (mg) of red clover daily for a year compared to a 2% decrease in those given a placebo.

Cancer

Preliminary animal research suggests that red clover might help treat prostate cancer.

In a mouse study, formononetin—a red clover isoflavone (a type of plant chemical)—had extra anti-prostate tumor effects when combined with the Taxotere (docetaxel) chemotherapy agent. These two medications were loaded into nanoparticles (nano-sized drug delivery system) and injected into the mice.

However, further studies in humans would be needed to confirm these results.

Other Uses

Historically, red clover was used for asthma, whooping cough, and gout. However, the research into these uses is lacking.

Red clover is also sometimes applied topically as an ointment or liquid extract for skin conditions such as psoriasis, eczema, or other rashes since it is believed to have anti-inflammatory properties. However, there's not enough scientific evidence for this, and use of red clover also carries a risk of skin irritations or allergic reactions.

What Are the Side Effects of Red Clover?

Like any other medication or supplement, side effects are possible with red clover.

Common Side Effects

According to a small study, participants who were in menopause didn't experience side effects when red clover extract was used for bone health.

However, in a meta-analysis of red clover's potential use for high cholesterol, common side effects of isoflavones—like the ones in red clover—may include:

• Back pain
• Bloating
• Stomach pain
  

Severe Side Effects

A severe allergic reaction is a serious side effect possible with any medication. If you're having a severe allergic reaction to red clover, symptoms may include breathing difficulties, itchiness, and rash.

While rare, other potential severe side effects may also include:

• Endometrial hyperplasia: In endometrial hyperplasia, there is an abnormal thickening of the endometrium. The endometrium is the lining of the uterus (womb). Symptoms may include irregular menstrual period bleeding, spotting, or post-menopausal bleeding.
• Breast cancer recurrence: Isoflavones—like the ones in red clover—may increase the chances of breast cancer returning. Symptoms of breast cancer may include breast skin changes, nipple discharge, and breast swelling or pain.

Call 911 and get medical help immediately if you have a severe allergic reaction or your symptoms are life-threatening.

Precautions

Your healthcare provider may advise against using red clover if any of the following applies to you:

• Severe allergic reaction: If you have a severe allergic reaction to red clover or its components (ingredients), you shouldn't take this medication.
• Breast cancer: For certain types of breast cancer, endocrine (hormone) therapy is typically used after surgery. This is to prevent these types of breast cancer from coming back. Since red clover may interfere with endocrine therapy, red clover isn't generally recommended.
• Pregnancy or breastfeeding: According to the National Center for Complementary and Integrative Health (NCCIH), red clover should be avoided while pregnant or breastfeeding. Reach out to your healthcare provider for a discussion on the benefits and risks of red clover in pregnancy or breastfeeding.
• Children: There is little information on the effects and safety of red clover in children.
• Older adults over 65: While older adults may have participated in some clinical trials, some study participants were individuals designated female at birth who were postmenopausal. Moreover, some older adults may be sensitive to side effects from medications. For this reason, take red clover with caution.
  

Dosage: How Much Red Clover Should I Take?

In studies of individuals in menopause, dosage of red clover supplements was typically 40 to 80 mg daily. While there are studies with red clover in humans, larger and well-designed studies are still necessary. For this reason, there are no guidelines on the appropriate dosage of red clover for any condition. Follow your healthcare provider's recommendations or label instructions if you choose to take red clover.

What Happens If I Take Too Much Red Clover?

There is little information about red clover toxicity and overdoses in humans. But in a case report, red clover might be linked to severe bleeding and bruising side effects—similar to Coumadin (warfarin) toxicity. This warfarin-like toxicity may have resulted from 5 to 6 cups of red clover-containing herbal tea for two weeks.

If you think you're experiencing an overdose or life-threatening symptoms, get medical help immediately.

Interactions

Use caution when taking red clover with the following:

• Blood thinners: Endometrial hyperplasia is a possible serious side effect of red clover, and symptoms may include abnormal bleeding. Large amounts of red clover might also be linked to severe bleeding and bruising. For these reasons, red clover may worsen the side effects of blood thinners, such as warfarin.
• Hormone therapy: Red clover contains isoflavones that may have some estrogen-like activity. For this reason, red clover may interact with endocrine (hormone) therapy for certain types of breast cancer, menopausal hormone therapy, and hormonal birth control.
• Methotrexate: Red clover might be linked to methotrexate toxicity. Methotrexate is a drug typically used for certain types of cancer, psoriasis, or rheumatoid arthritis.

It is essential to carefully read a supplement's ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.

How to Store Red Clover

Since storage instructions may vary for different herbal products, carefully read the directions and packaging label on the container. But in general, keep your medications tightly closed and out of the reach of children and pets, ideally locked in a cabinet or closet. Try to store your medicines in a cool and dry place.

Discard after one year or as indicated on the packaging. Avoid pouring unused and expired products down the drain or in the toilet. Visit the FDA's website to know where and how to discard all unused and expired products. You can also find disposal boxes in your area.

Ask your pharmacist or healthcare provider if you have any questions about the best ways to dispose of your medications or supplements.

Similar Supplements

Some of red clover's potential uses may include relieving menopausal symptoms and lowering high cholesterol. And other potentially similar supplements may include the following:

Black Cohosh

People may use black cohosh for several reasons, including menopausal hot flashes. A review suggested that black cohosh extract may relieve menopausal symptoms.

In general, black cohosh appears safe for up to 12 months of use. Like red clover, black cohosh's side effects may include stomach upset, cramping, and vaginal spotting. And like red clover, black cohosh isn't recommended for people with breast cancer. What's more, people with liver problems should also avoid black cohosh. And there is limited safety information about black cohosh use during pregnancy or while breastfeeding.

Evening Primrose

People may use evening primrose for various reasons, including relieving menopausal symptoms. Presently, there's not enough evidence to support evening primrose for any medical condition—like menopause.

In general, evening primrose appears to be safe. And unlike red clover, evening primrose might be safe during pregnancy or while breastfeeding. But similar to red clover, many of evening primrose's common side effects are related to the digestive system—like bloatedness or stomach pain.

Flaxseed

People may use flaxseed for several reasons, including high cholesterol and menopause. According to a review, flaxseed helped with heart and blood vessel conditions—like high cholesterol. But it's unsure about flaxseed oil's effects on heart and blood vessel conditions. And as for menopause, flaxseed's results are mixed.

As for safety, raw and unripe flaxseeds may typically have toxic chemicals. While small amounts of flaxseed supplements might generally be safe, flaxseed in very large amounts may be unsafe during pregnancy. And there's little information about flaxseed's safety while breastfeeding. As for side effects, flaxseed may cause constipation or diarrhea.

Sources of Red Clover & What to Look For

Don't take these supplements together or with red clover until you first talk with your healthcare provider. They can help prevent possible interactions and side effects. They can also ensure you're giving these supplements a fair trial at appropriate doses.

There are several different sources of red clover.

Food Sources of Red Clover

Red clover is naturally available as a wild plant in the legume family. You may see this dried herb used for tea.

Dietary changes may interact with your medications or affect your medical conditions. For this reason, talk with your healthcare provider first. They will help you safely make any dietary changes.

Red Clover Supplements

Red clover is available in various forms, including capsules and tablets. If you have difficulties swallowing pills, red clover is also available in the following dosage forms:

• Liquid
• Powder

There are also vegan and vegetarian options. The specific product you choose will depend on your preference and what you hope to get in terms of effects. Each product may work a bit differently, depending on the form. So, following your healthcare provider's recommendations or label directions is essential.

Summary

Red clover is sometimes used to ease menopausal symptoms, reduce bone loss, treat prostate cancer, and decrease cholesterol to support heart health. While results from some clinical trials are promising, large and well-designed studies are still needed to confirm red clover's benefits for these purposes.

For this reason, consumers should tread carefully and be aware of potential side effects and interactions. Before taking red clover, talk with your pharmacist or healthcare provider to help you safely achieve your health goals.