**Boise Baths: City Chlorine Gutting Summer Flora?**

By Franklin Everett Shaw

January 1, 2026

The smell of chlorine hangs heavy in the air around the natatorium at the Boise YMCA. It’s a smell many of us associate with summer, with childhood, with carefree fun. But for those of us who spend hours each week churning through the water, that chlorine might be doing more harm than good, especially to our guts.

Boise’s reliance on chlorine for pool sanitation, while effective at killing harmful bacteria, presents a potential problem for the delicate balance of our gut microbiome. This isn’t just about occasional discomfort; it’s about long-term health implications that Boise swimmers need to be aware of and actively address.

Chlorine, the silent disruptor, doesn’t discriminate. It wipes out both the bad bacteria and the beneficial bacteria in our gut. This disruption, known as dysbiosis, can lead to a cascade of health issues, from digestive problems and weakened immunity to even affecting mental health.

Consider Sarah, a Boise resident and competitive swimmer who trains at the West Boise YMCA pool six days a week. For years, she struggled with persistent bloating, fatigue, and frequent colds. Doctors ran tests, but nothing conclusive came back. It wasn’t until she started researching the effects of chlorine on gut health that she realized her swimming routine might be the culprit.

Sarah’s experience isn’t unique. Frequent exposure to chlorinated water, whether through drinking it or swallowing it while swimming, can significantly alter the composition and function of the gut microbiome. This is because chlorine reacts with organic matter in the water, forming disinfection byproducts (DBPs) like trihalomethanes (THMs) and haloacetic acids (HAAs). These DBPs are not only ingested but also absorbed through the skin and inhaled, further compounding the problem.

So, what can Boise swimmers do to protect their gut health? The answer lies in a multi-pronged approach, focusing on pre-swim preparation, post-swim recovery, and dietary adjustments.

Pre-Swim Strategies:

• Barrier Protection: Applying a thin layer of petroleum jelly or a specialized swim cream to the skin can help minimize chlorine absorption. Think of it as a shield for your skin, reducing the amount of chlorine that can penetrate and potentially affect your gut.
• Hydration is Key: Drinking plenty of water before swimming helps dilute the concentration of chlorine in your system if you accidentally swallow pool water. Aim for at least 16 ounces of water an hour before your swim.
• Prebiotic Power: Consuming prebiotic-rich foods like garlic, onions, bananas, or asparagus before swimming can help nourish the beneficial bacteria in your gut, making them more resilient to chlorine exposure.

Post-Swim Recovery:

• Shower Immediately: Rinsing off with soap and water immediately after swimming removes residual chlorine from your skin, minimizing further absorption. Use a gentle, pH-balanced soap to avoid further disrupting your skin’s natural microbiome.
• Probiotic Replenishment: Taking a high-quality probiotic supplement after swimming helps replenish the beneficial bacteria that may have been depleted by chlorine exposure. Look for a probiotic with a diverse range of strains, including Lactobacillus and Bifidobacterium.
• Fermented Foods: Incorporating fermented foods like yogurt, kefir, sauerkraut, or kimchi into your diet can also help boost your gut microbiome. These foods are naturally rich in probiotics and can provide a delicious and effective way to support your gut health.

Dietary Adjustments:

• Anti-Inflammatory Diet: Focus on consuming an anti-inflammatory diet rich in fruits, vegetables, and healthy fats. This can help reduce inflammation in the gut caused by chlorine exposure.
• Limit Processed Foods: Processed foods, sugary drinks, and excessive alcohol can further disrupt the gut microbiome. Minimize your intake of these items to support a healthy gut environment.
• Fiber is Your Friend: A high-fiber diet promotes the growth of beneficial bacteria in the gut. Include plenty of fiber-rich foods like whole grains, legumes, fruits, and vegetables in your daily meals.

But individual actions are only part of the solution. Boise needs to consider alternative pool sanitization methods that are less harsh on the gut microbiome.

Several U.S. cities have already adopted alternative methods, including:

• UV Sanitation: Ultraviolet (UV) light systems use UV radiation to kill bacteria and viruses without the use of chemicals. Cities like Scottsdale, Arizona, have successfully implemented UV sanitation in their public pools, reducing chlorine usage and minimizing DBP formation.
• Ozone Sanitation: Ozone is a powerful disinfectant that can effectively kill bacteria and viruses without leaving harmful residues. Denver, Colorado, uses ozone sanitation in some of its public pools, resulting in cleaner water and reduced chlorine demand.
• Copper-Silver Ionization: This method uses copper and silver ions to inhibit the growth of bacteria and algae. Some smaller towns in states like Vermont have found success with copper-silver ionization, particularly in smaller community pools.

Implementing these alternative methods in Boise’s public pools would require investment and infrastructure changes. However, the long-term benefits for the health of Boise’s swimmers would be significant.

The challenge lies in advocating for these changes at the local level. Boise residents can:

• Contact their City Council members: Express your concerns about the potential health effects of chlorine and urge them to explore alternative pool sanitization methods.
• Attend City Council meetings: Participate in public forums and voice your support for cleaner, healthier pools.
• Support local organizations: Partner with local environmental groups or health advocacy organizations to raise awareness about this issue.
• Share information: Educate your friends, family, and fellow swimmers about the potential risks of chlorine and the benefits of alternative sanitization methods.

The City of Boise Parks and Recreation Department should be encouraged to conduct a feasibility study to evaluate the cost-effectiveness and potential benefits of implementing alternative pool sanitization methods. This study should consider factors such as water quality, maintenance requirements, and the impact on swimmer health.

One common pitfall is assuming that simply taking a probiotic will completely negate the effects of chlorine. While probiotics are beneficial, they are just one piece of the puzzle. A holistic approach that includes pre-swim preparation, post-swim recovery, and dietary adjustments is essential for protecting gut health.

Another mistake is neglecting the importance of hydration. Dehydration can exacerbate the negative effects of chlorine on the gut microbiome. Make sure to drink plenty of water before, during, and after swimming to stay hydrated and support your gut health.

Ultimately, protecting the gut health of Boise’s swimmers requires a collaborative effort. By taking individual action and advocating for change at the local level, we can create a healthier swimming environment for everyone in our community. It’s time for Boise to dive into a future where our pools are not only clean but also gut-friendly.