Hello, dear readers! Welcome to our monthly letters column. We've had some interesting mail, so we'll get right to it.

-- Our columns often touch on the benefits of regular exercise on body, mind and mood. We heard from a reader who finds that, in some workout classes, pursuing those rewards may be putting your hearing at risk. "Various health clubs and rec centers where I've attended spin classes really crank up the music," he wrote. "The decibel levels sound off the charts. With the loud, sustained music and blasting instructions lasting 50 minutes or more, what risks to hearing do the students face?" Your concerns are valid. Hearing damage depends not only on volume, but on duration as well. Sustained sound levels above 85 decibels can harm hearing. Spin classes can hit 90 or even 100 decibels -- over the recommended safe exposure limits -- in a matter of minutes, not hours. At those levels, repeat exposure can lead to ringing in the ears, increased sound sensitivity over time and possibly even permanent hearing loss. Ear plugs would be a good idea.

-- Another important topic we’ve covered is getting the most out of a medical appointment. A reader wrote to share a practical tip. "When at a doctor's appointment, I often ask if I can record the findings on voice memos on my phone," he wrote. "That way I can replay the discussion, share with my wife and google anything I didn't quite understand. It is also a good record, for me, of my past issues." Each step of the way, you’re making good choices. That begins with making sure the practitioner is comfortable with recording. The recording itself can be a useful tool for all the reasons you outlined. A medical setting can be stressful. When information about your health is complex or emotionally charged, it’s easy to feel overwhelmed. An audio record allows repeated access to that information, giving you time to process it, research it and come up with follow-up questions that can lead to improved outcomes.

-- A recent column about potassium, an important nutrient, prompted this suggestion from a reader: "I appreciate your focus on dietary solutions to increase potassium intake, but you forget an additional source: low-sodium salt. It's a combination of sodium chloride, with added potassium chloride," he wrote. "It cuts sodium intake in half while providing 350 mg of potassium. Of course, those whose potassium intake should be limited due to a medical condition should steer clear." Yes, low-sodium salt can be a good source of potassium for people with normal kidney function. And for anyone with kidney disease, heart failure, diabetes or adrenal disorders, or taking medications that raise potassium levels, it can pose a health risk. It's a good idea to check with your doctor if switching is right for you.

Thank you, as always, to everyone who to took the time to write. You are keeping our inboxes full, so we will be back with a bonus letters column next week.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctors: I get frequent UTIs and was shocked you said they are caused by lax hygiene or sexual contact. I am meticulous about hygiene and have no sexual contact. My urologist said it is not the case all the time. This should have been worded differently in your article. Now my friends think I should take better care in cleansing myself. It’s quite frustrating.

Dear Reader: We regret that our discussion of urinary tract infections (UTIs) in a recent column did not include enough context to make clear that they can happen due to multiple causes. As we wrote, most uncomplicated UTIs happen when bacteria enter the urinary tract through common anatomical routes. Often, this is due to accidental transfer from the rectum, or during sexual activity. However, that’s not true for everyone. The focus of the column you are referencing was the growing challenge of antibiotic resistance in treating UTIs. Your letter gives us a chance to take a closer look at other ways UTIs can happen. We hope we can help ease the concerns of other readers like yourself.

When it comes to UTIs, anatomy is destiny. About half of all women will have at least one UTI in their lifetime. Only about 10% of men will have one. Part of the reason is that in women, the urethra is much shorter than it is in men. In men, the urethra is about 20 centimeters long. In women, it’s about 4 centimeters. This is a much shorter distance for bacteria to travel to infect a female bladder. Add in how close the urethra is to the rectum. This increases the risk of bacterial transfer even more, even with good hygiene.

Other factors can play a role in being susceptible to UTIs. One cause is the hormonal changes that occur during perimenopause and menopause. During these phases, the tissues of the urinary tract and the vagina change in ways that are favorable to harmful bacteria. Constipation, diabetes, inability to fully empty the bladder, catheter use, anatomical abnormalities and a weakened immune system can increase chances of getting a UTI. Vaginal and urinary microbiome composition and some spermicidal products can also play a role in UTI risk.

Another risk factor for UTIs brings us back to the topic of the original column, which is antibiotic resistance. This is when bacteria adapt to survive the antibiotics that would normally kill them. It's a widespread problem that makes infections of all types even more difficult to treat and control. With UTIs, there’s an epidemic of recurrent infections due to antibiotic resistance. This is when a drug is unable to completely kill the bacterium at the source of the infection. The surviving microbes then replicate, allowing the infection to persist or recur. Around 20% to 30% of women who have contracted their first UTI go on to experience a bounce-back infection.

The takeaway here is that UTIs reflect underlying biology rather than personal habits. It's a distinction that can lead to improved diagnosis, prevention and treatment.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctors: I am a 67-year-old physically active man. I was taking turmeric three times a day for several weeks to reduce workout-related inflammation. I ended up in the hospital with an abscess and small intestine perforation. I have read excess turmeric may cause this. Please comment.

Dear Reader: Turmeric is a flowering plant in the ginger family. This plant is native to India and has been used as a spice for more than 4,000 years. In addition to lending a sweet, earthy flavor to a wide range of dishes, turmeric contains a number of biologically active compounds. Perhaps best known of these is curcumin. Curcumin has been shown to have anti-inflammatory, antioxidant and possibly antiviral properties. Historically, traditional Chinese, Indian and Thai medicine have used turmeric. More recently, it has become a go-to in alternative medicine in the U.S. Turmeric and curcumin are used for a number of health conditions. They can ease pain and inflammation and reduce stiffness. They can also help with the decreased movement from conditions such as osteoarthritis.

A body of research has found that curcumin can derail some biochemical pathways involved in inflammation. This includes blocking the activity of signaling molecules that contribute to joint pain and swelling. These mechanisms, along with the antioxidant qualities it has, have increased interest in curcumin. It may be an aid in managing the chronic low-grade inflammation and oxidative stress that are biomarkers of metabolic disease.

One problem researchers have bumped into is that, when taken by mouth, curcumin is poorly absorbed by the body. The ability for a substance to be absorbed is known as bioavailability. This is an important aspect of any kind of medication. When someone ingests turmeric, only small amounts of the curcumin it contains can enter the bloodstream. So dietary supplements add certain substances to improve absorption. This can include piperine, which is a black pepper extract, and dietary fat.

Although turmeric and curcumin can be beneficial, it is possible for overuse to cause gastrointestinal side effects. These can include stomach discomfort, indigestion, nausea, loose stools and diarrhea. That said, there is no credible evidence that this would lead to an intestinal perforation or abscess. These are serious conditions that typically arise from infection, obstruction, reduced blood flow or underlying disease. Also, an abscess or an intestinal perforation would take far longer to develop than a few weeks of turmeric use.

When a serious medical event occurs with, or closely follows, a change in routine, like adding a supplement, it is understandable to infer a connection. Based on what we know about turmeric and curcumin and the timing in your case, this connection seems unlikely. They are probably not the direct cause of your intestinal issues. However, because turmeric can affect bleeding risk and interact with certain medications, we urge you to let your medical care providers know you have been using it.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

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