Friday Q&A: GLP-1s & bone density; screening for heart attack; hormone therapy after 65; & colon cancer in young people
Big topics in the inbox this week ✨
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In this week’s reader-submitted Q&A, we’re tackling these questions:
Should I worry about bone loss while on GLP-1s?
How do you screen for hidden heart attack risk?
Why won’t my doctor prescribe hormone therapy at 72?
Why is colon cancer striking younger people?
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The following questions have been lightly edited for length and clarity.
QUESTION #1: GLP-1S AND BONE DENSITY
I've been on semaglutide for eight months and have lost 35 pounds. My doctor is very happy (so I am). But I'm 58, postmenopausal, and now I'm reading that rapid weight loss can accelerate bone loss. Should I be worried? Is there anything I should be doing now to protect my bones while I'm on this medication?
- Margaret
Dear Margaret,
I’m thrilled for you, too! The metabolic benefits of semaglutide are real. Your concern is also legitimate. Rapid weight loss of any kind (through medication, surgery, or caloric restriction) can accelerate bone loss. Studies on semaglutide specifically show that a significant portion of weight lost comes from muscle mass, not just fat. And muscle matters enormously for bone health, particularly after menopause when estrogen is already low. That’s not a reason to stop the medication, but it is a reason to be strategic. (Read more on how GLP-1s work here.)
The good news is that there’s a lot you can do. Resistance training is the single most effective tool for preserving both muscle and bone density while on a GLP-1, even two sessions per week. Protein intake matters, too. I suggest aiming for at least 1 gram per kilogram of body weight every day (spread out over the day). Calcium and vitamin D are non-negotiable. And if you haven’t had a DEXA scan recently, now may be a good time to get a baseline so you and your doctor can track what’s happening to your bones over time.
Semaglutide and bone health are not incompatible; they just require active management. I hope that helps!
QUESTION #2: SCREENING FOR HEART ATTACK
A close friend (healthy, physically active, early 40s) just had a "widowmaker" heart attack. He now has two stents and feels lucky to be alive. It's shaken our friend group. Beyond managing the usual risk factors, are there screening tools that can catch this kind of hidden danger? Thank you, Dr. McBride.
- Alan
Dear Alan,
What a frightening wake-up call for your friend and for everyone around him. The “widowmaker” refers to a blockage in the left anterior descending artery, which supplies blood to a large portion of the heart muscle. When the flow of blood becomes blocked, the results are exactly as dramatic as the name implies. The sobering truth is that for many people, a heart attack is the first sign anything was wrong.
The conventional cardiovascular risk assessment—looking at blood pressure, cholesterol, diabetes/blood sugar, smoking, BMI, family history—is a good starting point, but it can miss a significant number of people who are walking around with substantial plaque and no warning signs. Fitness, in particular, creates a false sense of security. I have patients who ran marathons and had significant coronary artery disease.
A useful screening tool for patients at moderate risk for coronary disease is called a coronary artery calcium (CAC) score—a low-radiation CT scan that detects calcified plaque in the coronary arteries. Sadly, it isn’t always covered by insurance, but it can provide actionable information in the right context. A score of zero is reassuring. A high score changes the conversation about statins, lifestyle, and monitoring. I also recommend checking lipoprotein(a), or Lp(a)—a genetic cholesterol particle that standard lipid panels miss and that, if elevated, can increase the risk of atherosclerosis and heart attack. It runs in families, there’s no lifestyle fix for it, and most people have never had it checked.
Bottom line: a normal stress test and a fast 5K time are not the same thing as a clean bill of cardiovascular health. If cardiac issues run in your family, looking into these additional tests can be an actionable step in protecting your heart. (You can listen to my full episode on cardiovascular health here.)
QUESTION #3: TOPICAL HRT AFTER AGE 65
I am not happy. I'm 72 and my primary care clinic won't prescribe HRT to women over 65 or more than 10 years past menopause. Full stop. I’ve listened to you and Rachel Rubin talk about the safety and benefits of vaginal estrogen so I asked the nurse - she hinted that a compounding pharmacy might be an option. But I have no idea how to find a legitimate one or whether anyone will help me monitor me. My husband who is 80 has used topical testosterone for years without issue. Why is this so much harder for women?
-Barb
Hi Barbara,
Your frustration is completely justified and all too common. A blanket “no HRT after 65” policy is not evidence-based. It’s liability management dressed up as clinical guidance, and it is failing women like you every day. Sheesh!!
Here’s what the evidence actually says: vaginal or topical estrogen, which acts locally with minimal systemic absorption, carries near-zero risk and has myriad benefits for postmenopausal benefits (specifically it reduces the risk for urinary tract infections, vaginal dryness, painful intercourse, urinary symptoms like frequency and burning, and pelvic floor dysfunction).
The risk of estrogen (topical and systemic) has been overblown, ever since the misreading of the 2002 Women’s Health Initiative study. This was a very well done study that enrolled women who were, in many cases, years out from menopause and had pre-existing cardiovascular risk. The problem is that the study’s conclusions about breast cancer and cardiovascular risk were wildly overstated. They have since been substantially revised. The Menopause Society now states clearly that there is no fixed age cutoff for hormone therapy. Vaginal estrogen is safe for everyone. Decisions about whether or not to take systemic hormone therapy should be individualized based on symptoms, medical history, and risk profile.
(You can read my full thoughts on the ten year window and age restrictions for HRT here. On Tuesday 3/10, I’ll also post my recent conversation with menopause expert Lauren Streicher MD.)
As for compounding pharmacies: they can be legitimate and useful, particularly for topical formulations or doses not available commercially. Not all are created equal, so it's worth doing your homework on quality and accreditation before filling anything. More importantly, none of this should happen without a physician who specializes in menopause medicine in your corner, ideally someone who can evaluate your individual risk profile, prescribe appropriately, and monitor your progress over time. Finding that provider is the most important first step. They exist and increasingly, they may be accessible via telehealth if your local options are limited.
Your instinct that better options exist is correct, and you deserve a doctor who will help you explore these options.
QUESTION #4: COLON CANCER IN YOUNG PEOPLE
Colon cancer used to feel like something I'd worry about in my 70s. But I keep reading that rates are rising sharply in people in their 30s and 40s and that many of them had no obvious risk factors. I'm 44 and had a clean colonoscopy at 40. Should I be getting screened more aggressively? And does anyone actually know why this is happening?
-Alison
Hello Alison,
You’re right to be paying attention. Colorectal cancer rates in adults under 50 have been rising steadily since the 1990s, enough so that the U.S. Preventive Services Task Force lowered the recommended screening age from 50 to 45 in 2021. What’s driving it isn’t fully understood, but the leading suspects include changes in the gut microbiome, the rise of ultra-processed food, increasing rates of obesity and sedentary behavior, and possibly early-life antibiotic exposure, all of which affect the intestinal environment in ways we’re still untangling. (Read more on what your gut might be telling you here.)
A clean colonoscopy at 40 is reassuring, but it’s not a permanent pass. Current guidelines recommend repeat colonoscopy every 10 years if the prior one was normal, so you’re due again at 50 regardless. In the meantime, a yearly FIT test (a simple stool-based screen for occult blood) can provide a useful layer of surveillance between colonoscopies.
What matters most right now is knowing your family history and staying alert to symptoms. If a first-degree relative has had colorectal cancer or advanced polyps, guidelines recommend starting screening at 40, or 10 years before their diagnosis, whichever is earlier. And regardless of age, rectal bleeding, a persistent change in bowel habits, unexplained weight loss, or abdominal pain that doesn’t resolve all warrant prompt evaluation. The cancer that’s most treatable is the one caught early. I hope this is helpful!
Disclaimer: The views expressed here are entirely my own. They are not a substitute for advice from your personal physician.
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