Embarrassing Questions You NEED To Ask Your Doctor (Sex, Poop & More!)

Are you holding back embarrassing questions from your doctor? You're not alone! In this episode of The Longevity Show, Stanford-trained MD Dr. Hillary Lin…

Published December 19, 2024The Longevity Show

More than half of patients leave the doctor's office with a question they wanted to ask and didn't. Dr. Lin's argument is that the questions people swallow are disproportionately the diagnostically valuable ones, and she builds the episode out of cases that prove it. A man in his late fifties too embarrassed to raise erectile dysfunction turned out to have early-stage heart disease. A man whose libido vanished over a few months was on a beta blocker. A woman with sudden pain during sex had developed an allergy to her husband's semen. In each case the embarrassing symptom was the presenting sign of something else entirely.

The organising idea is that sexual and pelvic symptoms are systems reporting, not isolated complaints. Erectile dysfunction is vascular and neurological, so failure there is a reasonable proxy for failure elsewhere — including the coronary arteries. Low libido is downstream of medication lists, hormone levels and nutritional status. Pelvic floor dysfunction after childbirth is mechanical damage with a specific rehabilitation pathway. Dr. Lin's counter to the reflex of dismissing these as relational or cosmetic is that the physiological explanation is frequently the correct one and almost always the one nobody looked for.

She also does something more interesting than reassurance, which is to give the actual clinical detail — asymptomatic HSV shedding rates, boric acid dosing and its pregnancy contraindication, the incontinence prevalence figures — while being explicit about where the evidence is strong and where it is not. Her line on lysine for herpes is representative: three listeners raised it at the live recording, it does not work for everyone, and antiviral therapy remains the best intervention regardless. Her closing instruction is that if your doctor will not listen, the right move is a different doctor.

Before you watch

Erectile dysfunction is a cardiovascular finding before it is a sexual one. Dr. Lin's reasoning is mechanical: if blood flow and nerve function are failing in the penis, there is a good chance they are compromised elsewhere. Her patient Tom, in his late fifties and a former football coach, had assumed it was simply aging and had not raised it even with his wife — the conversation surfaced early-stage heart disease that was treatable immediately. Her framing is that addressing the ED was not the point; catching the heart disease was.
Medication lists are the first place to look for a libido that disappeared. Her patient Jack, in his early forties, lost interest over a few months with no obvious cause; the culprit was a beta blocker started for blood pressure. Dr. Lin notes beta blockers are no longer typically first-line for hypertension — still used for cardiac conditions and short-term anxiety — and that patients sometimes end up on them through allergy to alternatives or prescriber habit. The sexual side effects can include both reduced libido and erectile difficulty, and the fix was simply switching agents.
SSRIs and hormonal contraceptives belong on the same list. Fluoxetine and sertraline are common causes of reduced libido, and oral contraceptive pills can substantially change desire. Dr. Lin is notably skeptical of one adjacent claim — she looked specifically into whether hormonal contraceptives change who you are attracted to and found the evidence very weak, arguing general libido is genuinely affected while partner preference is not meaningfully so. She also pushes back on how localised long-acting methods are described: the standard teaching that a hormonal IUD or implant acts only locally is, in her view, not the whole truth, since those hormones do reach the rest of the body and can affect mood, hunger and sexual function. Her practical suggestion is to track symptoms yourself, because a doctor will reasonably chase the most obvious explanation first and the contraceptive may never come up.
Restrictive eating suppresses sex hormones, and the pattern hides behind apparent success. Emily, in her twenties and managing her weight effectively through severe restriction plus prolonged fasts every few weeks, expected her libido to improve alongside her body composition and instead lost it entirely. Her hormone panel came back low across the board, with free testosterone strikingly low even by female reference ranges. Dr. Lin treated it nutritionally rather than pharmacologically given her age — reintroducing healthy fats from avocado, nuts and olive oil, lean proteins, omega-3s from fatty fish, flavonoid-rich foods including berries, green tea and dark leafy greens, plus soy and red clover isoflavones — and added strength training to the running she was already doing. Libido returned within months.
Painful sex that starts abruptly deserves a full history rather than a psychological explanation. Dr. Lin describes a woman in her late thirties, newly married, sex-positive with no trauma history and no relationship problems, who developed severe pain with intercourse that was blocking her fertility plans. An hour of history-taking located the trigger: the pain began when the couple stopped using condoms. The diagnosis was human seminal plasma hypersensitivity — an allergy to semen — and she had seen multiple doctors before finding one who would listen long enough to find it.
That case has a real treatment pathway, which is the point of telling it. Barrier methods confirmed the diagnosis by resolving symptoms; an allergist then ran intravaginal graded desensitisation, gradually increasing exposure to build tolerance, on the same principle as allergy immunotherapy. For severe reactions, intrauterine insemination with washed sperm avoids exposure, and pre-coital antihistamines can manage localised reactions. She had also developed secondary vaginismus from the reaction, treated with graduated dilators. Dr. Lin discloses her own sublingual immunotherapy for dust, cockroach, cat and dog allergies as the comparison — a New York City necessity, as she puts it.
The postpartum pelvic floor statistics are worse than most people know. One study Dr. Lin cites found 48% of first-time mothers experienced urinary incontinence in the 6 to 10 weeks after giving birth, and 60% reported anal incontinence; pelvic organ prolapse affects around 29% of postpartum women, with a substantial fraction also experiencing pain during sex. Her patient Maria, after five children, was having to physically support her own uterus in order to pass stool — managed first with a pessary to hold the organs in place, then surgery.
Rehabilitation is standard practice elsewhere and improvised in the US. Dr. Lin notes that in France, postpartum women get biofeedback devices — inserted vaginally, with on-screen feedback showing whether the squeeze is strong enough — while in the US the equivalent is often a physical therapist emailing you a video to follow at home. Her emphasis is that this is not a short-term postpartum issue but determines continence and sexual function for decades afterward.
Incontinence is common enough that the shame is the anomaly. Estimates put urinary incontinence at nearly 40% of older women worldwide and among community-dwelling women in the US, and roughly 11–34% of older men; around 7.1% of the general population has monthly episodes of anal incontinence, rising with age. The adult diaper market was worth $9.8 billion in 2016 and is growing with population ageing. Dr. Lin's reframe is that a product enabling someone to stop organising their life around bathroom proximity is a freedom rather than a defeat.
On herpes, the transmission data is the part that dissolves the blame. Most transmission happens with no symptoms present — asymptomatic shedding occurs 10–20% of the time for HSV-2 depending on outbreak history, and a study of couples where one partner infected the other found over 70% of transmissions happened when the infected partner had no visible symptoms. HSV-1 typically causes oral and HSV-2 genital infection, but either can occur in either location, and oral transmission through kissing or shared utensils is entirely ordinary. Daily valacyclovir, acyclovir or famciclovir reduces transmission risk; condoms help but do not eliminate it, since shedding occurs outside the covered area. On the lysine that three listeners raised at the recording — typically 1,000–3,000 mg daily, divided — she is direct that it does not work for everyone and that antiviral therapy remains the best intervention, with supplements strictly complementary.
Boric acid vaginal suppositories have a real evidence base and a hard contraindication. Dr. Lin's specifics: 600 mg in a gelatin capsule intravaginally, daily for 14 days for vulvovaginal candidiasis — particularly useful for resistant species such as Candida glabrata or recurrent cases where fluconazole has stopped working — and 600 mg for up to 21 days for bacterial vaginosis, usually as part of combination therapy with other antimicrobials. It works by disrupting cellular processes and biofilm formation, the protective layer microorganisms use to resist treatment, and by modulating the local immune response. It should not be used in pregnancy; there is not enough safety data. She also steers listeners away from a DIY version one attendee described, recommending pharmacy suppositories at around $15 a pack instead.

Chapters

01:19

The Bottom Line: Sex Is Health

Questions

Is erectile dysfunction a sign of heart disease?

It can be an early one, and Dr. Lin treats it as a reason to investigate rather than a standalone problem. The reasoning is that erections depend on blood flow and nerve function, so when those fail in the penis there is a reasonable chance they are compromised in the heart and elsewhere too. Her case example is a patient in his late fifties, a former football coach who assumed it was just aging and had not mentioned it even to his wife — the conversation led to a diagnosis of early-stage heart disease that could be treated immediately. Her point is that the embarrassment costs more than the symptom does.

What medications can lower your libido?

Several common ones, and Dr. Lin's advice is to review the list before assuming the cause is psychological or relational. Beta blockers used for blood pressure can reduce both libido and erectile function — she describes a patient in his early forties whose sudden loss of interest resolved once the drug was switched, and notes beta blockers are no longer typically first-line for hypertension. SSRIs including fluoxetine and sertraline are frequent contributors. Oral contraceptive pills can meaningfully change desire. She also argues that long-acting hormonal methods such as the IUD and implant are described as more localised than they really are, since those hormones do reach the rest of the body and can affect mood, appetite and sexual function.

Can dieting or fasting affect your sex drive?

Yes, through hormone suppression, and Dr. Lin describes a case where the weight loss was working and that masked the problem. Her patient in her twenties was successfully managing her weight through heavy restriction plus prolonged fasts every few weeks, and expected her libido to improve — instead it disappeared. Bloodwork showed hormone levels low across the board, with free testosterone strikingly low even against female reference ranges. Rather than prescribe hormones given her age, Dr. Lin rebuilt the diet: healthy fats from avocado, nuts and olive oil, lean proteins, omega-3s from fatty fish, flavonoid-rich foods including berries and dark leafy greens, and soy and red clover isoflavones — plus strength training alongside her existing running. Libido returned within a few months.

Can you be allergic to semen?

Yes — the condition is human seminal plasma hypersensitivity, and it is rare enough that it is frequently missed. Dr. Lin describes a patient in her late thirties, newly married with no trauma history and a healthy sexual past, who developed severe pain with intercourse that was interfering with her plans to conceive. An hour of history-taking established that the pain began when the couple stopped using condoms. Resuming barrier protection confirmed the diagnosis, and an allergist then performed intravaginal graded desensitisation — gradually increasing exposure to build tolerance, on the same principle as any allergy immunotherapy. For severe cases, intrauterine insemination with washed sperm avoids exposure, and pre-coital antihistamines can manage localised reactions.

How common is incontinence after childbirth?

Far more common than the silence around it suggests. One study Dr. Lin cites found 48% of first-time mothers had urinary incontinence in the 6 to 10 weeks after birth, and 60% reported anal incontinence; pelvic organ prolapse affects roughly 29% of postpartum women. Longer term, estimates put urinary incontinence at nearly 40% of older women worldwide, with roughly 11–34% of older men affected, and about 7.1% of the general population experiencing monthly anal incontinence. She stresses that pelvic floor rehabilitation matters for decades rather than weeks — noting that France provides postpartum biofeedback devices as standard while US patients often get a video to follow at home.

Does boric acid actually work for recurring yeast infections or BV?

There is real evidence behind it, with specific dosing and one firm exclusion. Dr. Lin describes 600 mg in a gelatin capsule used intravaginally, daily for 14 days for vulvovaginal candidiasis — particularly valuable for resistant species like Candida glabrata, or recurrent infections where fluconazole is no longer working — and 600 mg for up to 21 days for bacterial vaginosis, typically alongside other antimicrobial treatment. Mechanistically it disrupts cellular processes and biofilm formation, the protective layer that helps yeast and bacteria resist treatment, and it modulates the local immune response. It should not be used during pregnancy, as safety data is insufficient. She recommends buying proper vaginal suppositories from a pharmacy, around $15 a pack, rather than assembling them yourself.

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