That fatigue might be hidden summer heat exhaustion

Hello everyone. This is Yuyu Kampo.

As the end of the rainy season approaches, the scorching sun is becoming more frequent. Even though summer is not yet in full swing, do you feel like you have 'a vague sense of sluggishness' or 'no motivation from the morning'? You might be experiencing something like that.

Are you familiar with the term 'heat acclimatization'?

In April 2026, the Japan Weather Association announced an initiative called 'Zero Heatstroke: Heat Acclimatization Front,' calling for preparations for 'heat acclimatization'—the process of the body getting used to the heat—to begin between April and May.

Heat acclimatization is the process by which the body gradually gets used to the mechanism of sweating to release heat. Originally, this is something that should be adjusted over a period of several days to two weeks, but if you have let that preparation period pass and your body is still not fully accustomed to the heat, it might be a sign that you are about to enter the peak of summer while your body is still in a state prone to significant strain.

A 'body not accustomed to heat' from a Kampo perspective

In Kampo, the energy used to protect and move the body is called 'Qi'. Qi is like a rechargeable battery inside the body.

During this time of year, when heat acclimatization has not yet been completed, Qi is busy responding to sudden changes in temperature and is being consumed more than usual. If you feel tired even though it is not yet the peak of summer, or if your appetite is not quite there, it might be a sign that your Qi is quietly starting to run out. In Kampo, this state is called 'Qi deficiency'.

Watch out for these signs of 'hidden fatigue'

• It takes time to get out of bed in the morning

• Your food intake is less than usual

• Your concentration drops sharply in the afternoon

• You get irritated by trivial things or become prone to tears

If even one of these applies to you, your body might be telling you that its 'battery is running low'.

This week's regimen to replenish Qi

What is important in caring for Qi deficiency is to borrow the power of crude drugs and formulas that 'replenish Qi'. This week, we will introduce in detail the representative Qi-replenishing crude drug 'Astragalus' and the formula containing that Astragalus, 'Hochuekkito,' on Tuesday and Wednesday.

If you do it now, before the full-scale heat arrives, there is still time. Let's gently take care of your body's rechargeable battery.

Editor's Note

At the turn of the season, there are days when I myself feel a heavy sluggishness in the morning. At such times, rather than forcing myself to move, I first try to tell myself, 'My battery might be a little low today.'

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