I’m a Pathologist: The "Biological Cost" of Ozempic and Mounjaro.
Dr. Amin Hedayat, MD
0:00 In 2024, humanity discovered something extraordinary.
0:04 [music] A weekly injection that could quiet hunger, stabilize blood sugar,
0:09 and melt weight faster than anything medicine had seen.
0:13 Headlines called it the end of obesity, the billiondoll miracle, the cure.
0:20 But I'm a pathologist, and in my world,
0:22 miracles don't really exist in this setting.
0:26 There's always mechanisms behind [music] everything.
0:29 Anytime you override a biological system that took 2 million years to evolve,
0:34 you are making a trade.
0:35 And every trade has an invoice, a cost to pay and a receipt.
0:40 Right now, the public conversation around GLP-1 medications,
0:44 some of as you may know them commercially, Ompic and Monero, is chaotic.
0:53 Half promise salvage and half warn of disaster.
0:58 Very few explain the biology.
1:01 So today we're going to fix that.
1:04 Please feel free to leave your experience in the comments below.
1:07 I read every single one.
1:08 I'm Dr.
1:09 Amin Haday, triple board certified pathologist,
1:11 physician, [music] and a susan clinical professor.
1:14 My career is spent reading the truth written inside human cells.
1:20 Cells don't argue.
1:21 Cells don't lie.
1:23 They respond to chemistry.
1:25 If clear science-based breakdowns like this help you,
1:28 feel free to like this video so more people can find evidence over confusion.
1:36 This video is your evidence-based mechanism first understanding of GLP-1 drugs.
1:42 How they work, why they work,
1:44 [music] why they sometimes backfire, and how to use them safely.
1:52 We'll walk through the evolutionary trap behind modern obesity,
1:57 the lizard brain that controls hunger,
2:00 the Gilla monster discovery that changed medicine,
2:04 the engineering behind 7-day appetite suppression,
2:08 the benefits, the trade-offs, and the real world risks.
2:13 And finally, the safe medically aligned exit strategy.
2:18 This is not fear.
2:19 This is not hype and it's purely physiology.
2:24 If you appreciate science explained clearly,
2:26 liking and subscribing helps these videos reach
2:29 more people who need clarity and not confusion.
2:33 So, let's begin.
2:34 You first have to understand why losing weight is biologically difficult.
2:40 Let me start with a truth almost no one hears from their doctor.
2:44 Obesity is not a moral failure.
2:47 It's an evolutionary success.
2:51 For 99.9% of human history, starvation, not overeating,
2:57 was the number one cause of death.
3:00 Anthropologists writing in the Journal of Human
3:04 Evolution describe how hunger shaped early human survival.
3:10 The people who could store fat the most efficiently survived.
3:14 Those who burned through calories quickly didn't.
3:19 So, you are the descendants of the world's best fat stores.
3:25 Your biology is optimized to survive scarcity,
3:28 but you live in an age of abundance.
3:31 Your genes expect famine.
3:34 You're surrounded by Uber Eatats and Door Dash.
3:38 And by the way, no affiliation.
3:40 This mismatch is what evolutionary biologists call an evolutionary mismatch.
3:47 Your biology is ancient.
3:50 Your environment is new.
3:53 And this conflict makes weight loss
3:56 feel like swimming against a biochemical current.
4:00 But it gets more interesting once you understand the wiring.
4:04 In the deepest part of your brain lies the hypothalamus,
4:09 the lizard brain, responsible for survival,
4:12 temperature, thirst, stress, and hunger.
4:17 This region defends your body fat set point with military precision.
4:24 It uses two hormones to do it.
4:26 Grein, which is essentially the gas pedal,
4:30 is produced by the stomach when empty.
4:33 It travels up the vagus nerve and says we need food.
4:38 This is primal overpowering and has been shown
4:43 in nature reviews endocrinology to override willpower completely.
4:48 Then we have leptin which is the break.
4:51 It's produced by fat cells.
4:54 When stores are full, leptin tells the brain, "We have enough.
4:58 Stop eating." But here's the problem.
5:01 In obesity, the brain becomes leptin resistant just
5:07 like you stop smelling perfume after a few minutes.
5:11 This is why someone can have 80, 100,
5:14 even 150 lbs of energy stored in their body and still feel hungry.
5:21 This isn't weakness, it's wiring.
5:25 GLP-1 medications override this broken circuit.
5:29 But the discovery didn't begin in a lab.
5:32 It began in a desert with a venomous lizard.
5:37 In the 1980s, scientists noticed something fascinating.
5:41 If you inject sugar into someone's bloodstream, the insulin response is small.
5:47 But if they drink the same sugar, the insulin response is huge.
5:53 Why?
5:54 Because the gut warns the body in advance.
5:59 Intestinal cells called L cells release a hormone called GLP-1.
6:05 GLP1 does three things immediately.
6:08 It prepares the pancreas for insulin.
6:11 It slows the stomach.
6:13 It tells the brain we're satisfied.
6:17 This is called the incretin effect.
6:20 first described in the journal of clinical investigation.
6:23 But natural GLP-1 breaks down in just
6:27 two minutes because of an enzyme called DPP4.
6:32 If scientists wanted to use GLP-1 as a drug, they needed to outsmart DPP4.
6:40 The breakthrough came from a creature most people
6:44 have never even heard of, the Gilla Monster.
6:48 In the deserts, there is a venomous lizard that eats only a few times a year.
6:55 A researcher named Dr.
6:57 John Ang discovered its venom contain a molecule
7:00 called extendin 4 described in endocrinology in 1992.
7:07 Accendin 4 acts like GLP-1,
7:11 binds the same receptor, but doesn't break down quickly.
7:16 It doesn't get sliced apart by DPP4.
7:19 It survives.
7:21 This was the blueprint for the first GLP-1 medications.
7:27 But modern scientists took this idea and engineered something far more powerful,
7:34 a hormone that can survive for 7 days.
7:39 This is the part that blows people's minds.
7:42 Smoglutide, the molecule in ompic and wiggoi is a triumph of modern chemistry.
7:51 Researchers wanted something that behaved like natural GLP1 but lasted
7:57 long enough to be effective as a weekly therapy.
8:02 They did two brilliant things and it was discussed in nature biology in 2017.
8:08 They changed one amino acid.
8:12 This prevents DPP4 from cutting the molecule.
8:16 They attached a C18 fatty acid tail.
8:20 This tail binds to albumin which is a massive
8:23 protein circulating in your blood for about a week.
8:28 Albamin acts like a cruise ship.
8:31 Semaglutide attaches to it and coast through your bloodstream for days.
8:37 A hormone that should last only 2 minutes now lasts 168 hours.
8:45 This one modification changed the landscape of metabolic medicine.
8:51 And then came the upgrade.
8:55 Terzepatite known as Monero and Zepbound doesn't activate just one receptor.
9:05 It activates two GLP1 and GIP.
9:09 The dual action was first described in the New
9:13 England Journal of Medicine in 2022 comparing tzipatite to semolutide.
9:20 When combined, GLP1 quiets appetite.
9:25 GIP stabilizes nausea and enhances glucose control.
9:32 This synergy allows for deeper appetite reduction
9:36 with potentially better tolerance for many patients.
9:40 This is why turepite often leads to greater average weight
9:44 loss than semlutide in clinical trials though individual results vary.
9:50 We've covered the evolutionary trap, the wiring,
9:54 the discovery, the engineering, and the upgrade.
9:58 Now, we need to talk about the part nobody explains clearly.
10:01 The trade-offs, the risks, the physiology behind side effects.
10:06 It's not fear, not hype, just biology.
10:10 GLP-1 medications work in part by slowing stomach emptying,
10:14 something documented extensively in gastroenterology research,
10:20 including clinical gastroenterology and hepatology in 2023.
10:25 For many people, this effect is mild and therapeutic.
10:31 It keeps food in the stomach longer, reducing appetite.
10:37 But for a subset of individuals,
10:39 especially at higher doses, this delay can become more pronounced.
10:45 Some people experience nausea, reflex,
10:47 bloating, early fullness, slower digestion.
10:52 Most of the time these symptoms are manageable
10:56 but sometimes they improve with dose adjustment but in rare
11:02 cases the slowing can be significant enough that clinicians
11:07 evaluate for delayed gastric emptying sometimes referred to as gastroparesis.
11:14 Case reports published in GI literature describe
11:17 a small number of patients developing more severe symptoms.
11:22 Bloating, vomiting, and difficulty handling solid meals.
11:27 Again, it's rare, but it's real.
11:32 Not a guarantee, but important to understand.
11:36 And then there's something patients don't hear until the day of surgery,
11:40 the anesthesia problem.
11:43 If your stomach empties more slowly than usual,
11:46 you may have residual food in your stomach even after fasting.
11:51 This matters because anesthesia turns off the protective airway reflexes.
11:57 If vomiting occurs while sedated, stomach contents can enter the lungs.
12:03 Sometimes anesthesiologists call this aspiration.
12:07 Because of this, the American Society of Anesthesiologists in 2023 issued
12:13 updated guidelines recommending special precautions
12:17 for patients on GLP-1 medications before surgery.
12:22 This doesn't mean anesthesia is unsafe, but it does mean your anesthesiologist
12:29 needs to know you're on these medications.
12:32 So, awareness is prevention.
12:36 Let's talk about the pancreas.
12:38 One of the most misunderstood topics in the GLP-1 discussion.
12:43 There have been reports of pancreatitis,
12:45 which is the inflammation of the pancreas in people taking GLP-1 medications.
12:51 Large clinical trials, including those published in gastroenterology in 2022,
12:57 show that the overall risk appears low,
13:00 but the prescribing information include caution for a reason.
13:05 People with a history of pancreatitis, very high triglycerides,
13:10 heavy alcohol use already carry a baseline risk for pancreatic inflammation.
13:17 For these individuals,
13:18 clinicians often use extra caution when considering GLP-1 drugs.
13:25 Most patients will never experience this issue.
13:28 But if someone on these medications develops persistent severe abdominal pain,
13:35 that is something a physician should evaluate.
13:38 This isn't fear.
13:39 It's simply understanding the physiology and respecting individual risk factors.
13:46 Every GLP1 medication has a boxed warning
13:50 related to thyroid sea cell tumors in animals.
13:55 specifically rodents.
13:58 Here's the nuance.
13:59 Rodents have many GLP-1 receptors on their thyroid C cells.
14:04 Humans have far fewer.
14:07 This is why rodent studies showed tumors and human studies
14:12 have not shown a clear increase at least so far.
14:17 This study was published in thyroid journal in 2023.
14:21 However, and this is important,
14:24 people with a personal or family history of medularary thyroid cancer
14:29 or the genetic condition men too are
14:33 generally advised not to take these medications.
14:37 Not because we've proven harm in humans,
14:41 but because we don't yet have 20-year population data.
14:47 This is what good medicine does.
14:49 It weighs uncertainty honestly and protects
14:54 the people who have known genetic vulnerabilities.
14:57 Muscle loss.
14:58 This is the most underrated biological
15:01 trade-off and one that surprises almost everyone.
15:05 When you lose weight quickly from any method, you lose both fat and muscle.
15:11 On GLP-1 medications, appetite drops dramatically.
15:16 Protein intake often decreases.
15:18 strength training becomes harder.
15:21 Nausea can reduce food variety.
15:25 Emerging studies, include those in the Obesity Journal in 2023,
15:30 show that without deliberate nutritional and resistant training support,
15:36 some patients lose a meaningful percentage of lean mass.
15:41 Why does this matter?
15:43 Because muscle is the engine of your metabolism.
15:48 The main side of glucose disposal, a buffer against insulin resistance,
15:56 a protector against falls, a predictor of longevity.
16:01 So less muscle means lower metabolic rate,
16:06 lower metabolic rate means easier weight gain.
16:13 This is not unavoidable, but without strategy, it is very common.
16:19 This is why the protein floor and strength training,
16:23 which we'll cover in the next part, are non-negotiable.
16:27 Now, let's talk about facial changes.
16:29 There's a lot of buzz about ompic face.
16:33 Here's the truth.
16:34 It's not the drug damaging the skin.
16:37 It's rapid fat loss.
16:40 When fat pads in the face shrink quickly,
16:43 the skin doesn't always retract at the same pace.
16:47 Plastic surgeons and dermatologists,
16:49 including those publishing in the aesthetic surgery journal in 2024,
16:54 describe this as a simple volume change.
16:59 It's not a toxicity reaction.
17:00 It's physics.
17:02 Slower, steadier weight loss preserves facial structure better.
17:07 Strength training and protein intake helps too.
17:12 This is a topic I hear quietly in clinics and see openly in support groups.
17:18 Some people describe feeling less impulsive,
17:22 less interested in food, calmer, more stable, and for many, this is a benefit,
17:29 especially those who struggle with emotional or binge eating.
17:34 But a subset describe something different.
17:38 Less motivation, less pressure, muted joy,
17:42 a grayscale feeling, lower reward drive.
17:48 It's not sadness.
17:49 It's not quite depression, just reduced spark.
17:55 Pre-clinical research in translational psychiatry published
17:59 in 2024 and ongoing human studies suggest
18:03 GLP-1 receptors in the reward pathways including
18:06 the nucleus encumbent may modulate dopamine signaling.
18:13 Not everyone, not dramatically in most, but enough for people to notice.
18:20 This is why monitoring your mental and emotional
18:24 landscape is important while on these medications.
18:29 If you feel flatter than expected, your clinician probably wants to know.
18:35 Now we arrive at the question everyone asks.
18:38 If I stop ompic or monero, will I gain the weight back?
18:43 The most evidence aligned answer is
18:47 many people regain weight without a strategy.
18:51 Not because they failed, because biology rebounds.
18:56 In the step one extension trial published
18:59 in New England Journal of Medicine in 2022,
19:02 participants regained roughly 2/3 of the weight they lost 12
19:08 months after stopping unless they had a robust lifestyle support.
19:13 Here's why this happens.
19:15 This is the part nobody explains clearly.
19:19 Hunger hormones surge back.
19:22 While on GLP medications, ghrein, your hunger hormone is suppressed.
19:28 When the medication leaves your system, ghrein doesn't return to baseline.
19:33 It overshoots.
19:36 This is well documented in metabolic
19:38 studies published in endocrine reviews in 2021.
19:42 Number two, appetite returns faster than satiety signals.
19:47 the brain stem, the hypothalamus regains sensitivity before the gut does.
19:54 That mismatch creates a transient hyper hunger period.
20:00 Number three is muscle mass has decreased.
20:04 During weight loss, people often lose some lean mass.
20:08 Less muscle means a slower metabolic rate.
20:12 This is well documented in obesity journals in 2023.
20:17 So when appetite returns, the engine is smaller.
20:24 Fat reaccumulates faster than muscle.
20:29 This is a universal physiological pattern called preferential atapose regain.
20:37 This was demonstrated in metabolism journal quite well in 2019.
20:42 Fat comes back quickly.
20:45 Muscle rebuilds slowly.
20:48 This combination creates what researchers call rebound physiology.
20:53 This is not about willpower.
20:56 This is not about character.
20:58 This is chemistry.
20:59 It's physics.
21:00 And physics can be engineered.
21:04 That brings us to the path forward,
21:07 which are my protocols that are based on peer-reviewed literature.
21:12 If you are on GLP-1 medications now, or if you ever plan to stop,
21:18 these next steps are core of protecting your biology.
21:23 Of course, this has to happen after you speak to your personal physician.
21:29 These protocols are supported by evidence from journals like sports medicine,
21:35 cell metabolism and nutrition reviews.
21:39 This is how you prevent muscle loss.
21:43 This is how you minimize rebound and land safely.
21:49 Rule number one, the protein floor.
21:53 This is a non-negotiable.
21:56 When appetite is low, protein is the first thing to disappear,
22:01 but it is the last thing your body wants to lose.
22:06 Aim for adequate protein intake daily.
22:10 Your clinician should guide your specific target.
22:13 If solid food feels heavy, there are alternatives such as clear whey isolate,
22:21 collagen and essential amino acids, dairy proteins, and egg white proteins.
22:28 Why?
22:29 Because leucine and other amino acids directly signal the muscle to stay intact.
22:37 Protein is proactively your muscle insurance
22:40 and muscle is your metabolic insurance.
22:44 This was shown in journal of physiology in 2020.
22:48 Rule number two, strength training is mandatory.
22:53 There is no drug, no supplement,
22:55 no hack that can replace mechanical load on muscle.
23:01 Resistant training two to four days per week is helpful.
23:06 You can try squats, deadlifts, rows, presses, pulls.
23:13 This signals your body, don't break down this tissue.
23:18 We need it.
23:20 Studies in sports medicine 2023 show that even 2 days per week
23:25 of resistant training can drastically reduce lean mass loss during weight loss.
23:32 This is not about looking fit.
23:35 This is about metabolic preservation.
23:38 Rule number three, taper slowly.
23:41 If you ever decide, of course,
23:43 in synergy with your medical doctor to come off GLP-1 medications,
23:49 do not stop abruptly.
23:51 A sudden drop in GLP1 signaling creates a rapid rebound in appetite.
23:57 A gradual taper allows hunger hormones to recalibrate,
24:02 satiety signals to normalize,
24:06 your routine to strengthen, your muscles to grow, your metabolism to stabilize.
24:13 This approach is supported by clinical
24:15 observations in obesity medicine practices and aligns
24:20 with the physiology described in endocrinology
24:23 and metabolism clinics which was published in 2022.
24:28 Your body needs time to readjust.
24:32 Give it that time.
24:34 Rule number four is use fiber as a mechanical satiety tool.
24:41 Once medication doses decrease,
24:44 your stomach begins sending hunger signals again.
24:49 To bridge this gap, use high volume,
24:51 low calorie foods to stretch the stomach's mechanical receptors.
24:56 You can uh try oats, beans, berries, vegetables, lentils, psyllium husk.
25:06 This strategy is backed by satiety
25:09 research published in appetite journal in 2020.
25:14 Chemical satiety by GLP1 transitions
25:19 to mechanical satiety with fiber and volume.
25:26 This is how you hand the baton from the drug to your stomach.
25:32 Rule number five, monitor mood, motivation, and joy.
25:37 GLP-1 receptors exist in the reward pathways of the brain.
25:43 Some individuals experience a calmer, quieter relationship with food,
25:49 which can be beneficial, but a smaller subset describe it muted emotional tone.
25:58 If your motivation drops, if you lose interest in hobbies,
26:04 if life feels flatter, speak with your physician.
26:08 Studies in translational psychiatry in 2024 are exploring this finding.
26:14 It may be dose related, transient, or it may require adjustment.
26:22 Your emotional landscape is as important as your metabolic one.
26:28 GLP-1 medications have taught us something profound.
26:32 Obesity is biology, not a moral issue.
26:38 For many, these medications reduce cardiovascular risk,
26:43 improve metabolic health, stabilize blood sugar,
26:48 calm obsessive food thoughts, break cycles that have lasted for decades.
26:55 For others, these drugs are a bridge,
26:58 a tool that helps them build new habits while biology stabilizes.
27:04 And for some, there are real tradeoffs that require careful navigation.
27:12 There is no oneizefitsall answer.
27:16 There is only informed consent, evidence-based decisionmaking,
27:21 and respect for the complexity of the human body.
27:26 You're not weak.
27:28 You're not broken.
27:30 You're not a moral failure.
27:33 You're a human being living in an environment
27:35 your biology was never designed for.
27:40 And now finally you have a tool, a powerful one,
27:44 pair it with a protocol that honors your physiology.
27:50 Thank you for your time, your curiosity,
27:52 and your commitment to understanding your body on a deeper level.
27:56 Let's continue building a life that is healthy,
28:00 coherent, energized, and uninflamed.
28:03 [music] I'm Dr.
28:05 Hayad and I'll see you in the next