Hop

What is Hop?

Hop is the dried flower of a climbing plant, Humulus lupulus. The soft, papery cones are also called strobiles. Most of the world's crop goes into beer.

In European folk use the same cones were taken as a calming herb. People drank a weak tea at night. Others filled a small pillow with the dried flowers and slept on it.

The Irish name is leannlus, the "ale herb". That name shows how closely the plant was tied to brewing.

Here is the short verdict. Human evidence for hop is thin. The best studied use is sleep, and most of those trials mixed hop with valerian.

Long use in a tradition is not proof that a herb works. It is not proof that it is safe either. Both points apply to hop, and they are stated once here rather than in every section below.

Hop is not a strong sedative. It will not knock you out. Most people who try it notice little or nothing, and that is a fair thing to expect.

How does Hop work?

No one has pinned down how hop works in the body.

Hop holds bitter resins. As the cones age, these break down into a small compound called 2-methyl-3-buten-2-ol. In animal studies, this compound raises sleep time.

The amount in a cup of tea is low. Whether it reaches the brain in useful amounts in people is not known.

In cell studies, hop extracts act on GABA receptors. GABA is the brain's main calming signal. Some sleep drugs work at the same place.

That is lab work, not proof in people. A cell dish is not a sleeping person.

Hop also holds a strong plant estrogen. In lab tests it binds estrogen receptors in the body. This is the reason hop extracts have been tested for hot flushes in menopause.

The bitter taste may have a simpler role. Bitter herbs were used to wake up appetite and ease a heavy stomach. That effect is mild and short.

What forms does Hop come in?

Hop is sold in several forms.

Dried cones, loose or in tea bags, are the oldest form. You steep them in hot water.

Capsules and tablets hold a dried extract. The strength on the label varies between brands.

Tinctures are liquid extracts in alcohol. They are taken in drops in water.

Many sleep products pair hop with valerian. Some add lemon balm or passionflower. Most human trials used these mixtures, not hop on its own.

Hop pillows are a folk form that is still sold. The dried cones sit in a small cloth bag near your head.

Hop essential oil is sold for scent. It is very strong and is not meant to be swallowed.

Beer holds hop, but it also holds alcohol. Alcohol breaks up sleep later in the night, so beer is a poor way to take this herb.

Where it comes from:

Hop has a long, well recorded place in European life.

Growers added hop to beer from about the ninth century. It kept the drink from spoiling and gave it bitterness. Brewing drove the spread of the plant across Europe.

Herbalists then wrote about the flowers as a medicine. Writers of the 1500s and 1600s listed hop for a heated stomach, a poor appetite and restless nights.

Hop pickers were said to grow sleepy in the fields. That story was repeated for centuries as proof of a calming effect.

By the 1800s, hop-filled pillows were a common home remedy for sleeplessness. King George III of Britain was reported to have used one.

In Ireland the plant was known as leannlus. Folk use there followed the same lines: a bitter tonic and a night-time tea.

Hop later appeared in European pharmacy books as a mild calming herb. These entries recorded custom and practice. They did not rest on trials as we would ask for today.

What does Hop help with?

• Trouble falling asleep: This is the most common modern use, and the best studied one. Folk use was simple. People drank a weak tea at night or slept on a hop pillow. Most trials tested hop with valerian, not hop alone. These trials were small. Some found people fell asleep a little faster than with a dummy pill, and some found no clear gain. Because the two herbs were mixed, we cannot say what hop added. The honest reading is a small, uncertain benefit for some people.
• Restlessness and mild nervous tension: Tradition treated hop as a calming bitter for restless, keyed-up people. In animal studies, hop extracts lower activity and raise sleep time. In cell studies, they act on calming brain receptors. Human trials here are few and small. Some used hop with other herbs and found modest easing of tension scores. Hop is not a treatment for an anxiety disorder. If worry is affecting your work, sleep or relationships, see a doctor.
• Hot flushes in menopause: This use is newer and rests on the plant estrogen in hop. A few small trials tested a standardised hop extract against a dummy pill. Over about 12 weeks, hot flush scores fell somewhat more in the hop groups. The groups were small and the dummy pill also helped a lot. Longer and larger trials have not been done. Safety over months and years is not settled. Anyone with a hormone-sensitive cancer should not take this on their own.
• Poor appetite and mild indigestion: Hop is bitter, and bitter herbs were taken before meals to wake up appetite. European herbals listed hop for a weak stomach and slow digestion. Bitter tonics of this kind were common. Modern trials in people are essentially absent. The effect, if any, is mild and brief. Ongoing stomach pain, weight loss or a fading appetite needs a doctor, not a bitter tea.

What are the side effects of Hop?

• Drowsiness, which can last into the next morning
• Dizziness
• Headache
• Upset stomach
• Skin rash from handling fresh plants, known as hop dermatitis (a skin rash)
• Eye and throat irritation from hop dust
• Low mood or odd mood changes, reported rarely
• Allergic reactions, which are rare but can be serious

Good to know:

Most people who take hop by mouth have no trouble with it.

The common effect is drowsiness. That matters most if you drive, work with tools, or take other calming drugs.

Skin and eye problems mostly affect hop pickers and brewery workers who handle large amounts of the fresh plant.

Serious reactions are rare. Stop hop and get help if you have a rash with swelling or trouble breathing.

How much Hop should you take?

• Recommended daily: These are the amounts labels tend to carry. They are not advice for you. Tea products often hold about half a gram of dried cones per cup. Some labels allow up to a gram. Capsule labels often sit between 300 mg and 500 mg of dried extract. Combined sleep products hold less hop and more valerian. Strength varies a lot between brands. Follow the label on the product you hold, and ask a pharmacist if you take other medicines.
• Best time of day: For sleep, hop is taken in the evening. Many labels suggest a dose shortly before bed. It can make you drowsy, so daytime use is a poor idea if you drive or use machines. As a bitter for appetite, tradition placed it before meals.
• With or without food: Food does not matter much for hop. Taken as a bitter for appetite, it was given before food. If the tea or capsule upsets your stomach, taking it with a small snack may help.
• Time to effect: If hop does anything for you, it tends to be within an hour. Many people notice nothing at all. That is a normal result, not a sign you took it wrong. For hot flushes, the small trials ran six to twelve weeks before measuring change. If a week or two of use changes nothing, more time is unlikely to help.
• How long to take it: Hop is a short-term herb, not a daily habit. Traditional herbal medicine licences cover short use for sleep and tension. Products are usually reviewed after two to four weeks. Sleep trouble that lasts more than a month needs a doctor. So do hot flushes that wear you down. Long-term safety has not been studied, so no one can call years of daily use safe.