Koji Amazake for Fatigue: Why It’s Called a Drinkable IV

Koji amazake was loved by ordinary people during the Edo period (1603 to 1868) as a drink to ward off summer fatigue, while these days it is called the drinkable IV drip. While the numerous health benefits of koji amazake have been highlighted in recent years, the focus of this article is its fatigue-fighting properties. The sweet-tasting fermented drink made from koji malt helps not only with physical fatigue from exercise, but also with mental fatigue from work or studying.

Ueda Manami from Marukome Co., Ltd.’s Public Relations Department explains why she recommends koji amazake when people feel fatigued.

▶Koji Amazake: A Traditional Drinkable Beauty Serum

Koji amazake is a treasure trove of nutrients derived from fermentation

Amazake has a very long history. A beverage recorded as amanotamuzake in the Nihon Shoki [The Chronicles of Japan, a historical record completed in the year 720] is considered the origin of amazake.

During the Edo period, amazake vendors appeared, turning the beverage into a summer tradition. In those days, it was cherished not only for restoring bodies weakened by the summer heat but also as a drink to prevent hangovers and nausea.

While amazake is associated with New Year’s celebrations, its inclusion in haiku poems as a seasonal word (kigo) for summer likely stems from these historical uses.

Which leaves the question: Why does koji amazake have such beneficial effects on health?

“The glucose abundant in koji amazake provides energy for physical activity. The body, of course, breaks down the carbohydrates in food into glucose for use as an energy source. With koji amazake, most of its carbohydrates have already been broken down by the enzymes in the rice koji, allowing the body to quickly absorb them. Another characteristic of koji amazake is its rich content of vitamin B1, which promotes the conversion of nutrients into energy, and amino acids that form the proteins that make up the main component of muscles.”

In fact, these components of koji amazake are almost identical to those found in IV drips. It makes perfect sense, then, that koji amazake can help combat fatigue.

“Koji amazake contains many other nutrients. And all of these are created through the power of fermentation. So besides being safe and reassuring, koji amazake is attractive because it lets you obtain a wide range of nutrients at once.”

Top-class athletes love koji amazake

Koji amazake’s potential to ward off fatigue has been confirmed in joint research trials by Marukome and Professor Kawaguchi Mikiko from the Faculty of Home Economics at Otsuma Women’s University.

The trial involved 20 student athletes on the Otsuma Women’s University basketball team. The trial subjects drank 250 ml of Marukome’s Koji Amazake within 30 minutes after practices. The trial looked at differences in their fatigue levels compared to when they drank barley tea, which they normally consume during practices.

“Drinking koji amazake for 10 days reduced the degree to which trial subjects felt ‘exhausted and lacking energy/vitality after practices’. Similarly, the degree of physical tension felt after practices was lessened when koji amazake was consumed.

“These findings suggest that of the components in koji amazake, glucose and amino acids were particularly beneficial for health and recovery. Glucose is recommended to replenish energy expended during physical exercise.”

■Degree of fatigue and physical tension after drinking koji amazake versus drinking barley tea

*The Profile of Mood States — Second Edition (POMS 2) was used to assess the degree of fatigue and physical tension. POMS 2 is a self-reporting tool that assesses the fluctuating feelings and mood states of individuals. It measures eight areas: seven mood areas — Tension – Anxiety, Depression – Dejection, Anger – Hostility, Vigor – Activity, Fatigue –Inertia, Confusion – Bewilderment, and Friendliness, plus total mood disturbance (TMD), a comprehensive indicator of negative emotions. POMS 2 is applicable in athletic settings as well as in clinical and education contexts.

It turns out that many athletes competing at the highest levels in Japan drink koji amazake.

“I noticed that nearly all the athletes on a long-distance relay team I visited drank koji amazake. These were top national-level athletes, so I’m sure they are constantly mindful of building fatigue-resistant bodies through diet, stretching, massage, and other methods. That they included koji amazake in their training regime proves they recognize its health benefits.”

Another distinction is the fatigue relief koji amazake can deliver isn’t limited to post-exercise exhaustion.

“Children studying for exams and adults involved in protracted work or meetings often feel mentally fatigued from the expenditure of brainpower and concentration.

“Glucose is, in fact, the brain’s sole energy source. That’s why I recommend drinking koji amazake when you feel mentally drained too.”

How to drink koji amazake for fatigue relief

How should a person drink koji amazake to reduce or recover from fatigue?

“For sure, you should drink it when you feel tired after exercising or work. But I also recommend drinking it before physical activity or before starting work. Basically, anytime you are about push yourself more than normal.”

Ueda also suggests you drink koji amazake instead of snacking.

“Personally, when I feel a bit tired or a bit hungry while working, I drink koji amazake. It really clears my head. Some people might eat zero-calorie snacks when they’re a little hungry to watch their calories. But those types of snacks don’t really replenish your energy and leave you feeling unsatisfied.

“Conversely, koji amazake provides glucose for energy and has a naturally derived sweetness, so even a small amount feels quite satisfying. Marukome’s Koji Amazake, in particular, comes in a compact size and can be stored at room temperature. Because it’s handy to carry around, you can enjoy its benefits anytime.”

▶Koji Amazake: A Traditional Drinkable Beauty Serum