For centuries, North American black cohosh has been used as an herbal treatment. The plant is now a popular remedy for menopause symptoms. It may help relieve your hot flashes and night sweats (vasomotor symptoms).
The rhizome or underground part of the plant goes into your dietary supplements. Rhizome refers to the bulbs below the ground.
These lumps tend to grow sideways (horizontal) with the roots shooting out. They hold the nutrients for the plant and you, too.
What Is Black Cohosh?
The plant grows in long, thin stems that bloom with white flowers. It belongs to the same family as the buttercup.
The scientific names for it are Actaea racemosa and Cimicifuga racemosa. In the past, the plant was also called:
- Bugbane
- Macrotys
- Snakeroot
- Rattleweed
- Rheumatism weed
This herb grows in Eastern North America from Georgia to Ontario. And you might notice it in the West from Missouri to Arkansas.
It's been a part of traditional medicine for centuries. Native Americans used it to treat fever, cough, pain, and menstrual problems.
How to Use Black Cohosh
Certain parts of black cohosh are poisonous, such as the white or red berries. But the rhizome or underground part of the plant may contain substances that act like medicine. These phytonutrients include:
- Glycosides (sugar molecules) that might have antioxidant, anti-inflammatory, and blood pressure-lowering properties.
- Isoferulic acids, substances that may help lower inflammation (anti-inflammatory).
- Phytoestrogens (hormone-like substances) that may help your bones, skin, heart, and reproductive health.
You can get the supplement in these forms:
- Capsules
- Dried root to use in tea
- Extracts to mix in water
- Liquid tincture
- Powder
- Tablets
Is the black cohosh plant edible?
The plant itself isn't edible. In fact, parts of it are poisonous, like the roots and berries. It's only safe to take black cohosh in a supplement form.
Black Cohosh Benefits
People have taken the supplement for many reasons. They claim the herb can improve sleep or anxiety and help ease menopause symptoms.
Some say the plant relieves hot flashes from breast cancer treatments, too. But there's mixed evidence to support these benefits.
Black cohosh for menopause
The most common use for this herb helps manage menopause symptoms, like your:
- Headaches
- Hot flashes
- Mood changes
- Sleep problems
- Heart palpitations
- Night sweats
- Vaginal dryness
A recent review of 22 studies found it may help ease general menopause symptoms and hot flashes.
Because of limited evidence, the North American Menopause Society and the American College of Obstetrics and Gynecology don’t recommend black cohosh.
Black cohosh for hot flashes
A review of supplements approved in Europe showed improved hot flashes and other menopause symptoms. But it's hard to prove if they work. Early studies were of low quality and couldn't confirm any benefits.
Newer studies are of better quality, but use different formulas and doses. The evidence isn't firm. So it's a good idea to talk to your doctor before trying this herb.
Black cohosh for breast cancer
Breast cancer treatments, like tamoxifen (Nolvadex), can cause menopause-like symptoms. These include hot flashes, sweating, or sleep problems.
A couple of studies treated symptoms with black cohosh but got mixed results. Others found no difference between the plant and a placebo (an inactive pill). But some studies showed a lower number and intensity of hot flashes after taking the herb.
Black cohosh may act like estrogen (a sex hormone) in some parts of the body. Some experts worry that black cohosh may help hormone-related cancers grow. But a review of 26 studies found no support for this claim. And one small study showed postmenopausal women lowered their breast cancer risk by half after taking it.
There are also a few studies to suggest the herb can lower your chances of breast cancer coming back after treatment. But talk to your doctor before taking it because it's still unclear.
Black cohosh for sleep
There's not a lot of research, but the herb may help you sleep longer in menopause. Some say they were less likely to wake up during the night. It's not clear, but it may help your hot flashes while you're sleeping.
Black cohosh for anxiety
In a few studies, the plant helped lower anxiety for postmenopausal women. In a recent review of 35 studies, the herb improved symptoms. It also helped with sleep, concentration, and fatigue.
But one small study didn't find benefits after taking it. There's not enough reliable information to know if it helps.
Black cohosh and weight
It's not as common, but a weight gain is reported as a side effect. And your chances can be higher if you take more of it.
Other benefits of black cohosh
Other uses for the supplement have less support. It's unknown if it can regulate periods, ease PMS symptoms, or induce labor. And researchers don't know if it helps your arthritis pain. Or if the plant can slow bone loss in osteoporosis or lower your blood pressure.
Weigh the benefits and risks before you try this herb. And always talk with your doctor before taking any supplement.
Black Cohosh Dosage
For menopause symptoms, most studies use a black cohosh dose of 6.5 to 160 milligrams (mg). The recommended dose ranges from 20 to 80 mg a day — about two capsules or tablets. Each tablet should contain 1 mg of the antioxidant, 27-deoxyactein.
Directions for taking this supplement in other forms vary. If you're using a tincture, the dose is 2 to 4 milliliters, one to three times a day, mixed into tea or water.
Follow the directions on the bottle's label or your doctor's recommended dose. Be sure to ask your doctor how much black cohosh is safe for you. This supplement isn't meant to be used long-term. Some experts recommend using it less than six months at a time.
It's always a good idea to talk with your doctor before starting any new medicine or supplement. And find out about any potential side effects for your health.
Black Cohosh Side Effects
Black cohosh may cause side effects like headaches or an upset stomach. But you can get other symptoms, too. And with higher doses, symptoms are more likely.
Unlike medications, dietary supplements aren't made under strict rules. A recent study tested 320 different brands of black cohosh. About half of them contained other ingredients.
So, your side effects can depend on what's in your supplement. It's rare, but sometimes you may have:
- Dizziness or lightheadedness
- Rash
- Nausea or vomiting
- Excessive sweating (diaphoresis)
- High blood pressure (usually at higher doses)
Some very serious liver problems have been reported after using this herb. Although it's rare, some reports say the supplements weren't labeled correctly.
How this happens and what causes the problems is unknown. But if you have liver problems or take medications affecting your liver, you'll likely want to avoid it. And always check with your doctor before taking black cohosh.
Risks for black cohosh
Although it seems safe for most people, the plant contains potentially reactive substances. So get medical advice before taking it. The plant may not be safe if you:
- Are pregnant or chestfeeding
- Have or have had breast or uterine cancer (hormone-sensitive conditions)
- Have or have had endometriosis
- Are a child under 18
- Have a liver disease
- Are at risk for stroke or blood clots
- Have a seizure disorder
- Have allergies to aspirin
Medication interactions
People taking medicines should talk with their doctor first. Although it's a supplement, it may interact with your medications, such as your:
- Chemotherapy medicines (tamoxifen or irinotecan)
- High cholesterol medication (statins)
- Anti-allergy medication (fexofenadine)
- Heart medication for irregular heartbeat (amiodarone)
- Diabetes medication (glyburide)
Black Cohosh vs. Blue Cohosh
Blue cohosh (Caulophyllum thalictroides) is another North America herb. It's different from black cohosh.
Native Americans used the herb to induce labor. And some nurse-midwives still use it to speed up labor. But the plant may not be safe. Studies report blue cohosh used to stimulate labor may cause serious heart problems in newborns.
If taken during pregnancy, blue cohosh may cause birth defects, too. Experts also don't recommend it while chestfeeding. There isn't enough research to show that it's safe.
Takeaways
It's still unclear, but black cohosh may help your menopause symptoms like hot flashes. You can get the herb as a capsule, powder, tincture, or extract. Like any supplement, black cohosh may cause side effects. Check with your doctor before you try it to see what's right for your health.
Black Cohosh FAQs
Can you get black cohosh naturally from foods?
Black cohosh comes from the roots of the plant. It's only available as a dietary supplement.
Does black cohosh increase estrogen?
The herb doesn't increase the hormone estrogen. However, it may contain phytoestrogens (plant-based estrogens). These substances may act similar to estrogen in some parts of your body.
Does black cohosh cause weight gain?
Weight gain can be a side effect of black cohosh. But it is less common and usually minor.
How much black cohosh should I take for hot flashes?
The recommended dose is between 20 to 80 milligrams a day. Ask your doctor how much of this supplement you should take.
How long does it take for black cohosh to work?
Supplements work differently for each person. Some studies have reported improvements in menopause-related hot flashes after two to four weeks.
