Late June marks the peak of Japan’s rainy season. The sharp swings in barometric pressure and soaring humidity can trigger headaches, fatigue, and dizziness — a cluster of symptoms often called “tsuyu-daru” (rainy season malaise). Here is how to stay comfortable and healthy through the wet weeks ahead.

Why Barometric Pressure Affects Your Body

During the rainy season, low-pressure and high-pressure systems pass through in quick succession. The inner ear detects these pressure shifts, and when it overreacts, the autonomic nervous system goes out of balance, causing headaches, nausea, and vertigo. Roughly one in three Japanese people experience some form of “weather-related pain.” On days when pressure swings are severe, avoid overexertion and take it easy. Weather forecasting apps can help you identify your personal trigger patterns so you can prepare in advance with medication or lifestyle adjustments.

Keeping Your Indoor Environment Comfortable

Humidity often exceeds 80% during the rainy season, making it difficult for sweat to evaporate and throwing off your body’s temperature regulation. Use a dehumidifier or your air conditioner’s dehumidify setting to maintain indoor humidity between 50-60%. This season also encourages mold and dust mites. Ventilate your home regularly, clean frequently, and place desiccants in closets and shoe cabinets. After bathing, run the exhaust fan and wipe down walls and floors to prevent mold growth.

Eating to Support Your Body Through the Rain

Digestive function tends to slow in humid weather, leading to water retention and sluggishness. Foods with natural diuretic effects — such as pearl barley, adzuki beans, and winter melon — help flush excess moisture from your body. Fermented foods like miso, natto, and yogurt support gut health and immunity. Ginger, garlic, and green onions warm the body and boost metabolism. Limit cold drinks and opt for warm herbal teas or hot water to maintain healthy digestion.

Stay Active and Sleep Well

Rainy weather reduces opportunities for outdoor exercise, but staying active is crucial for stress relief and autonomic balance. Indoor yoga, stretching, and light strength training are excellent alternatives. Sleep quality often suffers during this season due to pressure fluctuations. Choose breathable, moisture-wicking bedding and use air conditioning or a circulator to maintain a comfortable sleep environment. Limit screen time before bed and create a relaxing pre-sleep routine.

Conclusion

Managing your health during the rainy season comes down to understanding barometric pressure effects, controlling indoor humidity, and maintaining good daily habits. Pay close attention to how your body responds and take early action. With the right care, you can stay energized and comfortable even through the dreariest weeks of June.