Hops (Humulus lupulus) is most well known as a key ingredient in beer, whose antimicrobial properties were used to preserve the brew and prevent bacterial growth. Its sharp flavor is often the most forward in India Pale Ale (IPA) types of beer. However, long before its use in beverages, it was part of the botanical medicine toolkit of North American tribes and in Arab, Chinese, and Ayurvedic Medicine. Numerous groups of people have used hops to remedy stress, pain, headache, cramps, poor appetite, and many other things.

Before the Middle Ages, hops were used by monks in the form of beer to quell sexual urges.  Eventually, the Bavarian Beer Purity Act of 1516 was enacted which mandated that hops be included in beer production. The only other ingredients allowed were grains, yeast, and water. This Act was the first “drug law,” of the modern era. It also prohibited other psychoactive plants in the process, such as wormwood (a key ingredient in absinthe). With hops at the forefront of beer production, it arguably became a catalyst for one of the most influential beverages in human history. The bold reputation of hops cannot omit the fascinating evolution between it and its closest botanical relative: cannabis.

Hops and cannabis were once the same plant. The pair diverged as separate botanical species around 27 million years ago. Today they are collective members of the Cannabaceae family. However, hops does not contain cannabinoids of any kind.

Fossil specimens of pollen were used to date prehistoric samples of both hops and cannabis. The challenge is that the pollen of the two plants looks almost identical. Dr. John McPartland, a long-time cannabis researcher and botanist, has described the “niche theory” to identify plant remains based on the other botanicals found nearby. By examining the surroundings of the pollen samples, scientists are able to differentiate between hops and cannabis. For example, hops favors wet soils and is found near willows and poplars. In contrast, cannabis prefers rich alluvial, flood-disturbed soil, and high grassland flora. It's found growing alongside cereal grains and members of the Artemisia species.

Despite their distinction, there are many similarities between the healing attributes of the botanical duo. Hops and cannabis share some of the same terpenes and other phytonutrients and possess potent antibacterial and anti-cancer properties. Some of the dominant terpenoids found in hops are myrcene, alpha-humulene, and beta-pinene, which also appear in certain cannabis chemovars. Terpenes contained in the plant duo have been found to provide anti-inflammatory, antioxidant, anti-convulsive, pain-relieving, antidepressant, anti-anxiety, anticancer, neuroprotective, anti-allergic & antibiotic properties in numerous animal studies and clinical trials.

Hops strobile. Photo by Leslie Carrow

The parallels of hops and cannabis continue. Both plants require specific hours of day and night in order to bloom, and as a result, only grow at certain latitudes. Like cannabis, only the female hops flowers are harvested, yet the male plants are necessary for breeding purposes. Both botanicals are harvested in fall in the Northern hemisphere and are plucked when the strobiles (or buds in the case for cannabis) turn a golden amber color. Hops flowers produce lupulin powder, which is highly resinous, much like cannabis. Lupulin is responsible for the bitter flavor of the plant and is highly sought after for beer brewing. The medicinal attributes of hops are still being investigated, but there are some specific areas that it shows promise for as a natural remedy.

Hops for Sleep

One of the most well known and researched uses for hops is as a sleep aid. Despite this, the exact mechanisms of action and specific compounds responsible for its effect are not yet known. Lupulin, the yellow resinous powder found in female hops flowers, was first isolated by the French pharmacist Planche in 1813. Planche praised hops for its sleep-promoting properties and its ability to ease anxiety without causing constipation. This provided a major advantage as compared to opium treatments popular during the time.

Recent laboratory experiments have found that the sedative qualities of the plant are likely due to the activation of the melatonin receptor. Melatonin, a hormone produced by the pineal gland, is responsible for maintaining the circadian rhythm (sleep/wake cycle). Additionally, the bitter alpha-acid contained in hops strobiles increases the activity of GABA. GABA is a neurotransmitter in the body that slows down central nervous system signaling. A boost in GABA results in increased relaxation. Hops extracts have demonstrated the ability to improve the quality and length of sleep, and a healthy balance in the sleep/wake cycle.

Human research often examines hops in conjunction with other herbs, such as valerian. One study examined the effects of a drug preparation containing hops extracts and valerian root and found that the plant combination was effective in aiding rest. However, it hasn’t been well established if the sleep-promoting properties are a result of the action of the plants individually or the synergy between the two. Other evidence from a single animal study has suggested that hops may heighten the sedative effects of other drugs.

Digestive Aid

Both the British Herbal Pharmacopoeia and the herbal monograph from the World Health Organization have listed hops as a potential treatment for indigestion and a lack of appetite. In Japan, hops is used to boost of gastric function. The plant’s fame in beer-making in North America and Europe has inspired its placement in various liquors, taken before and after meals to aid digestion and boost appetite. Hops have become popular additions to bitters blends and trendy cocktails. For those who wish to abstain from alcohol, an infusion of hops can be prepared as a tea. It is bitter, so many people prefer to mix it with other herbs.

Menstrual Regulation

The influence of hops’ effect on the menstrual cycle was inspired when women harvesting the plant found that their periods started soon after picking the strobiles. The females working the full season also noticed that their menstrual cycles synchronized with their co-workers. This has lead researchers to examine the potential estrogenic activity of the plant.

Hops extracts have been developed in Belgium to relieve symptoms of menopause. A randomized, double-blind study of 67 women showed a significant reduction in menopausal discomfort. Additionally, 100 postmenopausal women experienced significant improvements in vaginal dryness and associated discomfort after using a hop based gel. Another component in the plant, a flavonoid called 8-prenylnaringenin, is a potent phytoestrogen that has been investigated as a dietary supplement to treat hot flashes in post-menopausal women. (Visit the American Botanical Council for more information on these studies).

Anti-cancer properties

Xanthohumol, one of the several active medicinal compounds in hops, was indicated as a “broad-spectrum cancer chemopreventive agent” in a preclinical study at Oregon State University. The research team encouraged more investigation for the use of hops as a preventative therapy for cancer. Certain flavonoids in hops (xanthohumol, dehydrocycloxanthohumol, and isoxanthohumol) have been shown to decrease the growth of human colon, breast, and ovarian cancer cells in vitro. Subsequent research in Belgium indicated that xanthohumol “effectively inhibits proliferation of prostate cancer.” In addition, humulone, one of the bitters in hops, was found to significantly suppress skin tumor growth in mice.

Other healing potential

The bitter acids in hops were shown to be potent against gram-positive bacteria. There is also an indication that hops compounds may be beneficial for infections in the mouth caused by Streptococcus mutans that result in dental plaque and cavities. Additionally, Chinese researchers discovered that xanthohumol is effective against HIV and suggested further investigation as a therapeutic treatment option for those with the virus.

The anti-inflammatory effects of hops also mirror that of cannabis. Xanthohumol may also protect brain cells from oxidative damage and hinder neurodegeneration that can lead to Parkinson’s disease and Alzheimer's. Additionally, this flavonoid inhibited inflammation, free radical formation, and cell death in a mouse model of brain trauma. The study also reported improvement in neurobehavior in the subjects. Hops may be beneficial for people looking to increase cognitive ability, or for those who have experienced brain trauma or have a predisposition for Alzheimer’s disease.

Like cannabis, hops has been found to regulate metabolism which has implications for weight management and metabolic syndromes. This can include obesity, diabetes, hypertension, and high cholesterol. Hops extracts have been shown to improve hyperglycemia (glucose intolerance and sensitivity) and reduce the negative impact of high-fat diets on cognition. They may also suppress the process of fat synthesis, which limits the quantity of fat to be stored in the body.

Condition hops may be used for: anxiety, restlessness, sleep disturbances, ulcers, menstrual regulation, pain relief, lack of appetite, tonic, cancer prevention (needs further investigation), neuroprotection (needs further study), bladder inflammation, digestive issues, cramping, tuberculosis, leprosy, acute bacterial dysentery, silicosis, asbestosis, dandruff, ringworm, sores, ulcers, skin injuries, acne, metabolic syndrome, obesity

By Sarah Russo

All photos taken by Leslie Carrow and cannot be reused without permission.

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