What is Hops?
Hops (Humulus lupulus) is a perennial climbing plant with vines that can grow up to 6 meters in height. It features serrated, palmate leaves and produces cone-like structures known as strobiles or hop cones. These cones contain the plant's flowers, which are commonly used in brewing beer.
Hops are native to temperate regions of the Northern Hemisphere, including Europe, Asia, and North America. They prefer moist, well-drained soil and thrive in areas with ample sunlight.
Primary Compounds
Hops contain various bioactive compounds, including:
Alpha and beta acids: Humulone, lupulone, and xanthohumol, which contribute to the plant's bitter flavor and antimicrobial properties.
Flavonoids: Including prenylflavonoids, such as 8-prenylnaringenin, which have estrogenic effects.
Essential oils: Myrcene, humulene, and caryophyllene, which contribute to the plant's aroma and flavor.
Traditional Uses of Hops
Hops have a long history of use in traditional medicine and brewing:
Sedative and Relaxant: Hops are known for their sedative and calming effects, often used to promote relaxation and alleviate insomnia and anxiety.
Digestive Aid: The bitter compounds in hops can stimulate appetite and improve digestion.
Menstrual Support: Hops have been used to relieve menstrual cramps and symptoms of menopause due to their estrogenic effects.
Brewing: Hops are a key ingredient in beer production, contributing bitterness, aroma, and antimicrobial properties to the finished product. They also help stabilize the beer and extend its shelf life.
Hops helps Sleep
Hops contain compounds that act on the central nervous system, promoting relaxation and sleep. and multiple studies have demonstrated the sleep-inducing effects of hops and its potential as a natural remedy for insomnia.
In one study, hops extracts were shown to boost GABA levels, GABA receptors, increase sleep times, and reduce restlessness during sleep. It also increased NREM sleep times.
Hops reduces Anxiety and Depression
A number of studies have demonstrated the ability of hops to increase relaxation, reduce stress, anxiety and depression.
In a 2017 study from Greece's Harokopio University, 36 healthy young adults with high levels of stress, depression and anxiety were tested. They were given either a hops supplement or a placebo for four weeks.
At the end of the four weeks, the researchers found that scores for stress, anxiety and depression levels were significantly lower among the hops group.
Hops lessens menopausal symptoms
Hops herb and its constituents have been found in multiple studies to have a positive effect upon menopausal symptoms. These include hot flushes (or hot flashes) and night sweats. These are termed vasomotor symptoms because they involve the ability of the blood vessels to expand and contract. The connection is that estrogen has a lot to do with regulating the blood vessels’ flexibility.
One clinical study of Hops and menopause came from Belgium’s Ghent University. It tested 67 menopausal women for three months. The researchers given either a Hops extract called 8-prenylnarigenin (8-PN) or a placebo. The study found that after six weeks and 12 weeks, those taking the Hops extract experienced a significant reduction in vasomotor symptoms – including hot flushes (or hot flashes) and night sweats.
The researchers utilized the Kupperman index to qualify the reduction in symptoms. The 100 microgram (low dose) was most effective in reducing symptoms. The researchers summarized their findings:
“Daily intake of a hop extract, standardized on 8- prenylnarigenin as a potent phytoestrogen, exerted favorable effects on vasomotor symptoms and other menopausal discomforts. Hop-derived prenylated flavonoids may provide an attractive addition to the alternative treatments available for relief of hot flushes and other menopausal discomforts.”
Additional studies since then have confirmed Hops’ ability to reduce menopausal symptoms. A 2013 review from Germany’s Dresden Technical University confirmed this and concluded that Hops extract will preferentially activate the alpha estrogen receptor. This rendered it the ability to have an estrogenic effect upon the mammary glands, according to the researchers.
Hops and Breast Cancer
About one in eight women in the U.S. will develop invasive breast cancer in their lifetime. According to the American Cancer Society, over 245,000 new cases of invasive breast cancer are expected among American women this year.
Breast cancer risk increases for a woman right about the age that estrogen levels begin to change. For this reason, we find that nature not only provides estrogenic remedies to help relieve menopause symptoms. Along with these, Nature also provides the active chemicals that help stop menopause-related cancers from developing.
Confirming this, recent studies from the University of Illinois and several other research institutions have determined that Hops helps prevent and inhibit the growth and expansion of breast cancer.
The UIC researchers have been testing Hops extracts for some time in the laboratory on breast cancer cells. With increasingly positive findings, they have discovered that another prenylnarigenin – 6-prenylnarigenin or 6-PN – activates a chemical pathway within the mammary cells that help prevent breast cancer cells from developing.
The research is being led by Dr. Judy Bolton, a professor of medicinal chemistry and pharmacognosy at the UIC’s College of Pharmacy. Dr. Bolton and fellow researchers applied the hops extract to multiple human breast cell lines. They found that the 6-prenylnarigenin compound stimulated a cellular pathway that increased detoxification among those cells. This pathway had been found in other research to reduce the risk for breast cancer.
“We need to further explore this possibility, but our results suggest that 6-PN could have anti-cancer effects,” Bolton said.
Compared to the 6-PN compound, 8-prenylnarigenin (8-PN) had weaker metabolic effects upon the breast cell lines, but it does increase anticancer metabolic activity in the breast cells.
The UIC researchers also tested other Hops extracted compounds such as isoxanthohumol and xanthohumol.
Other studies have also tested these two compounds from Hops, as well as Tetrahydro-iso-alpha. The latter was found to antagonize the alpha estrogen receptor – which helps defer estrogen-related dysfunction.
In 2015, researchers from Poland’s Wrocław University of Environmental and Life Science found that isoxanthohumol extracted from Hops prevented breast cancer and other cancer cells from proliferating:
“Isoxanthohumol exhibits an antiproliferative activity against human cell lines typical for breast cancer (MCF-7), ovarian cancer (A-2780), prostate cancer (DU145 and PC-3), and colon cancer (HT-29 and SW620) cells.”
Researchers from South Korea’s Konkuk University School of Medicine found that xanthohumol extracted from Hops also stopped the proliferation of breast cancer cells:
“Xanthohumol inhibited the proliferation of MDA-MB-231 cells through a mitochondria- and caspase-dependent apoptotic pathway. This result suggests that xanthohumol might serve as a novel therapeutic drug for breast cancer.”
Remember that each of these compounds – the 6-prenylnarigenin, 8-prenylnarigenin, xanthohumol and isoxanthohumol – are individual compounds extracted from Hops, and tetrahydro-iso-alpha acids is a collection of compounds.
These researchers have been studying the individual compounds extracted from Hops – likely in hopes to find a single anti-cancer compound. Their end game is to develop a drug from that extracted plant compound. This all started because the whole Hops herb was found to inhibit cancer growth.
The point is that these individual studies are telling us is what we have found repeatedly among nature’s herbal medicines: The whole herb provides a synergistic combination of many different medicinal compounds. Together they form the ability to fight and prevent disease. Each of the compounds may have a single effect, but when they are together in the whole herb, the effect is synergized and buffered.
The buffering effect of the multiple compounds in herbs is why whole medicinal herbs have a record of safety.
Breast cancer and estrogen
Breast cancer incidence has been to some degree tracking with hormone replacement therapy (HRT). HRT expanded during the 1980s and 1990s, as breast cancer incidence dramatically increased. Since 2002, after the Women’s Health Initiative research linked HRT and breast cancer incidence, HRT prescriptions have fallen.
As hormone replacement therapy prescriptions have fallen, so have breast cancer rates.
This relationship between estrogen levels and breast cancer is reinforced by this research, as well as the research on the Hops plant.
There are a number of other plants that provide natural phytoestrogens. Others, such as Hops, modulate the estrogen receptors for the better.
Again, we see the evidence that Nature takes care of itself. And if we let it, it can also care for our bodies too.
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