Expert Column: Staying Steady Through Autumn’s Temperature Swings — Warming from the Core with a Fermentation Bath

By Prof. Kazunori Ito
Professor, Faculty of Acupuncture and Moxibustion, Meiji University of Integrative Medicine / Director, Japan Enzyme Bath Association

Every month, Hakkou Ningen and Prof. Kazunori Ito publish a column on the enzyme bath — also called a fermentation bath — from the perspective of Eastern medicine and yojo, the Japanese tradition of everyday self-care. This is the English version of the October column.

When the body can’t keep up with the swing

Chilly mornings and evenings, then afternoons warm enough to make you sweat. Many people feel that their body is not quite keeping up with these swings in temperature. Late October is Soko, “frost’s descent” — one of the 24 seasonal divisions of the traditional calendar, when the first frost begins to fall. In Eastern medicine, care for winter is thought to begin in early November, with Ritto, the start of winter.

When the temperature moves up and down, the body is asked to adjust again and again. It is a little like keeping your foot on the accelerator — the sympathetic nervous system, the body’s “go” mode. Feeling sluggish, or tired even after a night’s sleep, can be seen as a signal from what Eastern medicine calls mibyo: a state that is not illness, but not quite full health either.

Warming from the inside with a fermentation bath

This is a good season to make use of a fermentation bath (enzyme bath). It uses the heat created as rice bran and sawdust ferment through the work of microbes, and it wraps the whole body in warmth without using hot water.

When we think about preparing for the cold, we tend to think of adding heat from the outside — more layers, more heating. In the yojo way of thinking, it matters just as much to regain the ability to warm up from within. The warmth of fermentation is said to reach gently deep into the body and to support circulation. As the body relaxes, it is thought to shift more easily from the accelerator to the brake — the parasympathetic nervous system, the body’s “rest” mode. You could think of it as warming up the engine before the real cold arrives.

Simple ways to take care

• Drink before and after. Have some water — a cup of plain warm water is a good choice — before and after the bath.
• Short on time? Try hands or feet. On days when a full bath is not possible, a fermentation foot bath or hand bath is an easy option: you simply bury your feet up to the ankles, or your hands up to the wrists, in fermenting sawdust. You can stay fully dressed, and it only takes a short time. Hands and feet are far from the heart and tend to get cold, so warming them gently is said to help warmth spread through the whole body.
• Keep the warmth. Afterwards, put on an extra layer so your neck, belly and ankles stay warm. The air is getting dry, so don’t forget to moisturize.
• Comfortable is enough. Sweating more is not better. Stop when it still feels pleasant. Once a week or once a month is perfectly fine.
• At home, too. On days when you can’t go out, simply soaking in a bath at 38–40°C (100–104°F) one to two hours before bed is self-care in the same spirit.

If you have a medical condition, or on days when you don’t feel well, please don’t push yourself, and talk to your doctor first.

Not perfect — just what you can

There is no need to blame yourself on days when you can’t keep it up. Feeling unsettled by the temperature swings is a sign that your body is responding sensitively to the change of season. Rather than aiming for perfection, do what you can, when you can. Little by little, bringing back time to warm up and relax is the gentlest way to welcome winter. As the season turns, why not make some time to warm yourself from the core?

This column shares general ideas from Eastern medicine and the Japanese tradition of yojo. It is not medical advice, and experiences vary from person to person. The original column was written in Japanese for the Japan Enzyme Bath Association.

About Prof. Kazunori Ito

Prof. Ito is a professor in the Faculty of Acupuncture and Moxibustion at Meiji University of Integrative Medicine in Nantan, Kyoto, and a director of the Japan Enzyme Bath Association. He has spent many years in research and education in Eastern medicine, and works with Hakkou Ningen on joint research into the enzyme bath and on academic conference presentations.

For wellness business owners

Hakkou Ningen has supported more than 80 enzyme bath openings across Japan — from Hokkaido in the north to Okinawa in the south — and now supports owners around the world. If you are thinking about offering an enzyme bath in your country, message us on WhatsApp to get our free program guide, or visit our opening program page.