What Are Hops?

Hops are the flower of the hop plant (Humulus lupulus), commonly used to make beer. However, in addition to flavoring ales and pilsners, hops have been studied for potential health purposes.

Many of the perceived benefits of hops are attributed to essential oils and flavonoid compounds found in flowers, like xanthohumol and 8-prenylnaringenin. These flavonoids may possess anti-inflammatory, antioxidant, and anticancer properties.

Hops also contain the bitter acids humulone and lupulone, which may have antimicrobial properties.

However, health claims surrounding hops are not well-supported by scientific evidence.

This article will dive deeper into the potential uses of hops. It will also discuss dosage, side effects, precautions, interactions, and storage information.

Uses of Hops

Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian (RD), pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent disease.

Herbalists and supplement manufacturers claim that adding hops to a diet can improve overall health and prevent certain diseases. Though, many of these claims are unsubstantiated. It's important to note that no supplement should be used to replace standard medical care for any health condition.

Here is a look at some of the current research.

Sleep Disorders

Various components found in hops are thought to have mild sedative properties that may have applications in medicine.

A few small studies have investigated the effects of hops on sleep-wake cycles using nonalcoholic beer.

One very small study included 17 nurses assigned female at birth. The nurses, who worked rotating or night shifts, were given hop-containing nonalcoholic beer at dinnertime for two weeks. Researchers monitored their sleep patterns with a wristband sleep tracker. The results suggested that the beer not only helped participants fall asleep slightly faster but also reduced anxiety levels. 

These results are similar to a 2014 study of 30 college students in which questionnaires were used to determine sleep habits. After one week of recording sleep habits, students were asked to drink nonalcoholic beer with their dinner for 14 days. Compared with the first week, the students reported significant improvements in sleep habits, including the time it took to fall asleep after drinking nonalcoholic beer.

Hops are sometimes combined with other herbs, like valerian and passionflower, to treat insomnia.

A 2013 study compared the sleeping pill Ambien (zolpidem) to a combination pill that contained hops, valerian, and passionflower. In the study, both the sleeping pill and the herbal remedy were found to be equally effective. However, it's difficult to determine if the hops were more or less effective than the other herbs in the study.

Hot Flashes

The flavonoid 8-prenylnaringenin found in hops is classified as a phytoestrogen—a plant-based compound that mimics the activity of the female hormone estrogen. Some believe that 8-prenylnaringenin can help increase estrogenic activity in the body, overcoming symptoms of estrogen deficiency, especially during menopause.

Hot flashes are a common side effect of menopause. Hops may be able to help ease this effect.

In both animal and human trials, hops supplementation has correlated with improvements in hot flashes. Various studies have found that when compared to a placebo, hops were thought to alleviate hot flashes associated with menopause.

However, the researchers noted the potential for adverse effects with long-term supplementation with hops. Additionally, further research is needed to determine an optimal dosing strategy.

Cardiovascular Disease

A flavonoid in hops called xanthohumol is believed to have properties that may help relax blood vessels and improve blood circulation.

One study performed on rats found that xanthohumol extracted from hops reduced calcification in arteries and veins. Researchers from the study believed these results to mean that xanthohumol may have a potential role in decreasing the risk of cardiovascular (heart) disease.

Although these results seem promising, and other lab and animal studies have drawn similar conclusions, the role of hops and xanthohumol has yet to be studied in humans. More research is needed in this area.

Cancer

Although hops cannot directly prevent cancer, xanthohumol, and other compounds in hops, may display anticancer effects.

According to a 2018 review, xanthohumol was found to kill various types of cancer in test tube studies. Xanthohumol was found to be cytotoxic, meaning that it "poisoned" and killed cells, including cancer cells. It was also found to trigger apoptosis, also known as programmed cell death.

More research, including human trials, must be conducted to draw conclusions.

Depression

Hops are being studied as a potential treatment for depression and other mood disorders.

A small human trial from 2017 looked at healthy college students with self-reported mood disorders. For the placebo-controlled clinical trial, 36 young adults with mild depression were given either 400 milligrams (mg) of Melcalin hops or a placebo (an ineffective substance) for four weeks. At the end of the study, those taking hops showed significant reductions in anxiety, stress, and depression levels compared to the placebo group.

Once again, though, further research should be conducted regarding hops and their potential role in treating mood disorders. More large-scale human trials are needed.

What Are the Side Effects of Hops?

When taken as a supplement, hops are believed to be generally safe and have minimal side effects. However, side effects are possible when taking hops and may be mild or severe.

Common Side Effects

The side effects of hops are few, and reactions to the supplement are rare.

Some people may experience drowsiness or dizziness when taking hops supplements.

Typically, these side effects will go away once you stop taking hops. If side effects don't improve or disappear, talk to your healthcare provider.

Severe Side Effects

Hops may cause hypersensitivity reactions in some people.

Hypersensitivity is characterized as an extreme allergic reaction. These reactions may occur within 24 hours of taking hops, or they may take longer to appear.

These reactions can range in severity, with anaphylaxis being a medical emergency.

You should seek immediate medical attention if you experience a severe reaction to hops.

Precautions

Certain people may not be able to consume hops, and others should take extra precautions before trying the supplement.

It's recommended that people who are pregnant or breastfeeding avoid using hops. This is because there is not enough research available to determine whether hops are safe for people in these groups.

People with estrogen-dependent conditions, including endometriosis and certain types of breast cancer, should avoid hops due to their potential estrogen-like activity.

Due to its sedative properties, hops should be stopped at least two weeks before surgery. The concern is that taking hops before surgery may amplify the effects of anesthesia.

Dosage: How Much Hops Should I Take?

Due to a lack of quality research, it is not known at what dose hops supplements are beneficial or at what point they may be harmful. Because of this, there are no standardized dosage recommendations for hops.

Hops extracts are generally considered safe in doses of up to 300 milligrams daily for three months or less. Hops bitter acids may be used in 35-milligram daily doses for the same amount of time.

It's best to follow dosage instructions on your hops supplement label or healthcare provider.

What Happens If I Take Too Much Hops?

Little is known about adverse events associated with taking too many hops. This is due to limited research regarding any potential toxicities.

Hops do not appear to cause liver injury or toxicity.

As with any supplement, you may be more likely to experience side effects if you take more hops than you should. Recall that potential side effects include drowsiness and dizziness.

To prevent potential adverse effects, use hops supplements only as directed.

Interactions

Hops may interact with a handful of medications, herbs, and other supplements, including:

• Estrogen
• Certain medications broken down by the liver, such as those metabolized by the CYP2C and CYP1A2 enzymes
• CNS (central nervous system) depressants, or sedative medications
• Herbs and supplements that act as sedatives
• Herbs and supplements with estrogen-like properties

Hops may interact with other medications, herbs, and supplements. Be sure your healthcare provider knows about all the medications, herbs, and supplements you use before starting hops.

It is important that you carefully read the ingredients list and nutrition facts panel of any new supplement. This will ensure you are aware of the ingredients and how much of each ingredient is included in the supplement. Please review supplement labels with your healthcare provider to discuss potential interactions with foods, other supplements, and medications. 

How to Store Hops

Store hops supplements in a cool, dry place. They should be kept away from extreme temperatures as well as direct sunlight. Typically, hops don't need to be refrigerated but follow any storage directions on the product label.

Discard any remaining hops supplements once the expiration date passes.

Similar Supplements

Other herbs and supplements that have been studied for similar uses as hops includes:

• Melatonin: A hormone that your body produces, melatonin has long been used as a natural sleep aid. Although research has been mixed regarding its efficacy and safety, a recent review and meta-analysis associated melatonin supplementation with improved sleep quality in adults with sleep disorders.
• Black cohosh: Black cohosh is an herb commonly used to treat hot flashes and other side effects of menopause. Compared to a placebo, black cohosh has been found to be a more effective treatment for hot flashes. However, it is not thought to work better than hormone replacement therapy (HRT).
• Allicin: A compound found in garlic, allicin has been studied for its potential benefits for heart health. According to a study from 2022, raw garlic juice intake may reduce levels of trimethylamine-N-oxide, or TMAO, a marker of increased risk of heart disease.
• Rhodiola rosea: Rhodiola rosea (R. rosea) is an herb commonly used in traditional medicine. Researchers from one review found that R. rosea has a moderating effect on mood, making it potentially beneficial for symptoms of anxiety, depression, and other mood disorders.

Talk with your healthcare provider about which herbs and supplements are right for you.

Sources of Hops & What to Look For

Hops may contain certain substances that may be beneficial for various health conditions. However, hops are not a vital nutrient required by your body, so there are no recommendations when it comes to food vs. supplement sources.

Food Sources of Hops

No solid foods naturally contain hops, but beer is often brewed with hops to add bitterness and flavor.

Some people choose to add dried hops to various dishes and recipes. However, they're generally used as supplements for health purposes.

Hops Supplements

Typically, hops supplements are sold in capsule, tincture, or powder forms. Tablets and other forms may also be available.

Most hops supplements are gluten-free and vegan. But be sure to check the product label if you follow these or other special diets. Some capsules may be made with non-vegan ingredients.

Dietary supplements are not required to undergo the rigorous testing and research that pharmaceutical drugs do. For this reason, the quality of supplements can vary from one brand to the next. To ensure quality and safety, only choose supplements from reliable, well-known brands.

While many vitamin manufacturers will voluntarily submit their supplements for quality testing by an independent certifying body (like USP, NSF International, and ConsumerLab), the practice is less common among herbal supplement manufacturers.

Summary

Hops are dried flowers from the Humulus lupulus plant that may have health benefits. Hops have been studied for potential uses in alleviating hot flashes, treating insomnia, and improving mood. However, research regarding the specific uses of hops is limited and conflicting.

Hops are generally considered safe to take, although some side effects, like dizziness and drowsiness, can occur. Moreover, hops may interact with some medications and other herbal supplements. You should talk with your healthcare provider before adding hops to your daily routine.