Summer, Sun - and a Sensitive gut?

Summer is usually associated with hot days and balmy nights. But for many people, the season also brings sluggish digestion, bloating, or an unusual feeling of fullness. One possible reason: the microbiome.

Heat, travel, and changes in eating habits can all challenge the complex ecosystem of trillions of beneficial gut bacteria.

How Heat and Vacation Time Affect Your Digestion

On hot days, our bodies switch to energy-saving mode: blood flow is redirected toward the skin to help cool us down. As a result, less energy is available for digestion. We also lose more fluids through sweating, which can slow down intestinal activity. The result: a sluggish gastrointestinal tract.

Studies show that while our gut flora is adaptable, it's also sensitive. The composition of the microbiome can shift with the seasons—often influenced by changes in diet and available foods. Travel also affects the microbiome: time zone shifts, unfamiliar cuisines, and new bacteria in local drinking water can all disrupt the gut’s usual balance.

How to Keep Your Microbiome in Balance This Summer

2. Eat light – high in fiber, plant-based, and fresh

In summer, the gut appreciates easily digestible food: colorful bowls with cooked vegetables, whole grains, or legumes provide valuable fiber. This fiber serves as food for the “good” gut bacteria, promotes a diverse gut flora, and supports overall well-being.

Scientific analyses show that a high-fiber diet significantly increases bacterial diversity in the gut – a key indicator of a healthy microbiome. Seasonal eating also plays a role. Those who eat more fresh vegetables, berries, herbs, and similar foods in summer supply their microbiome with important bioactive plant compounds, which studies have linked to positive changes in bacterial composition.

Tip: Go for cooked vegetables, quinoa, lentils, or oats – easy to digest and high in fiber. Cool dishes like salads or bowls are ideal.

Conclusion: Summer Is Microbiome Season

Summer can present new challenges for your digestive system. But with a few simple steps, you can actively support your gut feeling. Drink plenty of fluids, eat light and plant-based meals, and include fermented foods – this strengthens your microbiome and helps you feel your best, even in 30°C heat.

You might also be interested in:

• Gut Health – An Interview with Anne Peterson
• Fermentation – Your At Home Guide
• Intuitive Eating – Listening to Your Gut Feeling

Sources:

1. Gut-microbiota-targeted diets modulate human immune status
2. Seasonal Variation in Human Gut Microbiome Composition
3. Dietary Fiber Intake and Gut Microbiota in Human Health
4. Positive Health Outcomes Associated with Live Microbe Intake from Foods, Including Fermented Foods, Assessed using the NHANES Database
5. Wie der Darm unsere Gesundheit beeinflusst