By Taylor Hinds
This article is part of Rethinking Health, RethinkX’s ongoing series on the Health Optimizer Therapy disruption.
Humanity has been chasing the perfect body through pharmaceuticals for well over a century, with little success to date. Countless drugs have hit the market over that time promising to cut fat or build muscle effortlessly. But for one reason or another none have worked, or at least none have worked without serious consequences.
Now, for the first time, there is real opportunity for diet and exercise in a bottle. Health optimizer therapies, or the combination of GLP1 agonists and myostatin/activin inhibitors, are here and are poised to disrupt the way a metabolically healthy body is achieved, maintained and managed in a way that no other pharmaceutical solution ever has before.
The Graveyard of Miracles
The first widely used pharmaceutical weight-loss drug was called DNP, introduced in 1933. After rapid weight loss (among other symptoms) was noticed in WWI munitions factory workers working with DNP, it was eventually discovered in the 1930s that the substance boosted human metabolism by forcing cells to waste energy as heat rather than store it. Within a year of this discovery, over 20 companies were selling DNP over the counter as a weight loss pill. While it was very effective for rapid weight loss, it was also very dangerous. Reports of hyperthermia (cooking from the inside out - the opposite of hypothermia), cataracts, and sudden death accumulated with grim efficiency, and by 1938 the FDA had banned it and labeled it as “extremely dangerous and not fit for human consumption.”
The 1940s brought amphetamines, namely Benzedrine and its relatives, which suppressed appetite and elevated mood. Methamphetamine itself was actually approved for obesity in 1947. They worked very well until their addictive properties, psychiatric effects, cardiovascular risks, and near universal sleep disruption made them completely untenable. The 1950s and 1960s produced a generation of synthetic amphetamine analogues, including phentermine and diethylpropion, developed as cleaner alternatives to methamphetamine that could suppress appetite with fewer stimulant effects and lower addiction risk, a promise that only partially held up. The era's most notorious offering was the so-called "rainbow pills," cocktails of amphetamines, thyroid hormones, and diuretics dispensed by weight loss clinics with little oversight, and associated with multiple deaths before they were banned.
The 1990s, however, brought the most spectacular failure in diet pills: fen-phen. Fenfluramine and phentermine were never approved by the FDA as a combo, but in 1992, once people discovered the seemingly miraculous weight loss that could be achieved, doctors began prescribing them together, off-label. The “Phen” gave you energy and suppressed appetite, while the “Fen” made you feel full and canceled out the jitters. By 1996, over 18 million prescriptions had been filled in the United States alone, but by 1997, enough studies linking fenfluramine to heart valve damage and pulmonary hypertension had accumulated and Fen was quickly withdrawn. Despite this, hundreds of thousands of people showed some cardiac abnormalities years after stopping the drug and lawsuits ultimately cost its maker an estimated $21 billion. Phentermine however, which was not the cause of the heart issues, was still the most widely used weight loss medication in the US until 2026 when it was overtaken by GLP-1s.
The list of subsequent casualties goes on. Ephedra, wildly popular through the 1990s and into the 2000s, was banned in 2004 after being linked to heart attacks, strokes, and seizures. Sibutramine, approved in 1997 as a serotonin and norepinephrine reuptake inhibitor, was withdrawn globally in 2010 when long-term data revealed elevated cardiovascular risk. Rimonabant, a cannabinoid receptor blocker celebrated in Europe as novel and promising, caused severe depression and suicidality and was withdrawn in 2008, never having been approved in the United States.
Beyond prescription medicine, the vacuum left by ineffective treatments created fertile ground for a multi-billion-dollar supplement industry. Supplements like hydroxycitric acid, garcinia cambogia, raspberry ketones, & green coffee extract each rode their own wave of marketing (thank you Dr. Oz) before the evidence inevitably dissolved.
The Parallel History of Muscle
Anabolic-androgenic steroids were first synthesized in the 1930s to treat hypogonadism and muscle-wasting diseases, but their performance-enhancing potential was recognized almost immediately. By the mid-1950s, it was an open secret that Soviet weightlifters were already using testosterone and that prompted American team physician John Ziegler to develop a synthetic alternative. The result was methandrostenolone, released by CIBA Pharmaceuticals in 1958 under the name Dianabol, and it paved the way for dishonesty in sports for decades to come.
Through the 1960s and ‘70s, anabolic steroid use spread from elite athletics into professional sports and then into gyms worldwide. By 1975, the International Olympic Committee added steroids to its banned substances list and the first drug tests for steroids at the Montreal Olympics appeared in 1976, just in time to disqualify several weightlifters, including the gold and silver medalists. Nearly two decades later it was also proven that before winning nearly all the gold medals, and setting eight world records the East German women’s swimmers, many of them teenagers were being systematically dosed with Oral-Turinabol (Tbol) an anabolic-androgenic steroid. While at the games it was noticed that these women had deep voices, and masculine muscle and hair growth patterns, the full cost for them would only emerge years later: cancers, heart failures, liver tumors, and children born with birth defects
Scandals kept compounding throughout the 80s, 90s, and 00s including the Ben Johnson sprint scandal at the 1988 Seoul Olympics, baseball’s Steroid Era featuring Roger Clemens, Mark McGwire, Barry Bonds and A-Rod, the Lance Armstrong and Floyd Landis revelations in cycling, the BALCO scandal in track and field, the Russian state-sponsored doping program, and more. All of these made the steroid problem impossible for mainstream audiences to ignore. Escalating scandals led to the 1990 Anabolic Steroids Control Act in the United States which made unauthorized possession a felony.
The physical harms of anabolic steroids are well-documented and serious. These include suppression of the body’s own testosterone production, cardiovascular damage including enlarged hearts and dangerous cholesterol changes, liver toxicity, psychiatric effects including aggression and depression, hormonal disruption. These are the predictable consequences of overwhelming the body with far more male sex hormone than it was ever designed to handle. Unsurprisingly, in women and adolescents, the effects are often irreversible.
Human growth hormone (HGH) followed a similar trajectory to anabolic steroids, though it is a different class of molecule entirely. Unlike steroids, which are synthetic androgens, HGH is a peptide hormone naturally produced by the pituitary gland that governs growth, cell reproduction, and metabolism. Early supplies were extremely limited because the only source was cadaver pituitary glands, confining its use almost exclusively to children with severe growth deficiencies. That changed in 1985 when synthetic recombinant HGH became available through genetic engineering, suddenly making black market supply viable at scale. Athletes had been experimenting with cadaver-derived HGH since the early 1980s, and Ben Johnson admitted to using it alongside steroids in the lead-up to Seoul in 1988, but the synthetic version opened the floodgates. By the 1990s it was firmly embedded in elite sport, particularly cycling, bodybuilding, and track and field, and its appeal was compounded by the fact that it was extremely difficult to detect because it is chemically identical to the body's own hormone (until a reliable test was developed around 2000). The critical distinction from legitimate therapeutic use is in how it was being abused. Athletes and bodybuilders were not taking HGH to restore a deficiency or extend a natural signal. They were taking it at doses far above anything the body would naturally produce, for purposes entirely outside its natural role, and typically in combination with steroids and other compounds. The result was the same pattern seen with steroids: real short-term effects, but real long-term risks including joint pain, fluid retention, and potentially increased cancer risk. There is evidence that the strength benefits in healthy adults were far more modest than the black market price tag suggested.
These days, the era of muscle enhancement lives on, online. Anabolic steroids, human growth hormone, SARMs, and a rotating cast of newer compounds now move freely through online black markets and grey-market suppliers, feeding a subculture of predominantly young men whose pursuit of an idealized physique has been amplified by social media. The aesthetic template promoted by fitness influencers on Instagram and TikTok has created demand that legitimate medicine will not supply. The consequences are poorly tracked because the users are largely outside the medical system, but emergency physicians and endocrinologists have begun documenting a growing number of young men presenting with cardiovascular damage, hormonal collapse, and psychiatric crises from unsupervised use of multiple compounds simultaneously.
What All Those Drugs Had in Common
Every drug in the pharmaceutical history above was attempting to do the same fundamental thing, to override a biological system by forcing it beyond its natural parameters, often using an external agent that did not belong there.
DNP forced energy to waste as heat regardless of what the body needed. Amphetamines suppressed appetite by flooding neural pathways with stimulant signals. Fen-phen jammed serotonin receptors involved in appetite regulation, which turned out to also govern heart valve function. Ephedra activated the fight-or-flight response to force metabolism upward. Anabolic steroids swamped the body with synthetic androgens, disrupting the entire system governing testosterone production, reproduction, cardiovascular health, and mood. And HGH, though a peptide hormone the body naturally produces (like GLP-1), was administered at doses far beyond anything the pituitary would ever generate on its own, to force outcomes the body had no endogenous reason to pursue.
These drugs worked against the body’s regulatory systems, in every case the body eventually found ways to push back. The side effects were the inevitable consequence of forcing complex, evolved regulatory systems to behave as if their own signals did not exist.
This is exactly the lens through which skeptics view HOTs (GLP-1s and myostatin/activin inhibitors), as a more polished appetite suppressant and just another steroid, but this is where the analogy breaks down.
Working With the Body, Not Against It
Glucagon-like peptide-1 (GLP-1) is secreted by specialized L-cells in your gut every time you eat. It is a hormone your own body produces, not one invented by a pharmaceutical company. Furthermore, its biological role is exactly the same as what the GLP-1 drugs reproduce. It signals to the pancreas to release insulin in proportion to blood sugar, signals to the liver to stop releasing glucose, slows the movement of food through the digestive tract, and communicates with specific receptor sites in the brain that regulate appetite and satiety.
In the modern food environment, the natural GLP-1 hormone has too short a half-life to do its job as natural GLP-1 degrades within minutes of being released. The discovery that Gila monster venom contained a peptide, exendin-4, with similar properties but far greater stability, was the breakthrough that made GLP-1 pharmacology possible.
Semaglutide, engineered to survive in the body for over five days, does not supress your appetite like a stimulant drug does. It extends and amplifies a signal that your body already uses, already understands, and already has the receptor infrastructure to act on. This is why the side effect profile looks so different from previous weight-loss drugs. There are no hallmarks of stimulant toxicity, no heart valve damage, no sympathetic nervous system overstimulation. The main side effects, nausea and gastrointestinal discomfort, are the predictable result of the gut-slowing that is part of the hormone’s natural function. The result is a quieting of food noise (persistent, intrusive preoccupation with eating) and therefore less of a compulsion to eat.
GLP-1 receptors found in the gut, and they are also distributed across the cardiovascular system, kidneys, liver, and brain. This means the therapy works through two distinct pathways. First, it exerts direct, weight-independent effects, such as reducing systemic inflammation and improving how blood vessels function. Second, it triggers indirect, weight-dependent benefits. As the body sheds excess fat, secondary strain-related conditions like sleep apnea, joint pain, and high blood pressure naturally begin to resolve. By addressing both the biological signaling and the physical weight simultaneously, these therapies optimize health in a way that previous blunt instrument diet pills never could.
Myostatin Inhibitors: Removing a Brake, Not Pressing an Accelerator
The same logic applies with even greater precision to myostatin and activin inhibitors.
Myostatin is a protein your body produces specifically to limit muscle growth. Our ancestors lived in conditions of caloric scarcity, and maintaining large amounts of muscle tissue is metabolically expensive, so it makes sense to have a mechanism that ensures muscle mass does not grow beyond what can be sustained. The ActRIIB receptor it binds to acts as a gatekeeper on the genes responsible for muscle growth and breakdown.
Myostatin-blocking antibody drugs do not introduce a foreign, synthetic androgen into the body like steroids do. They selectively inhibit a specific protein that acts on a specific receptor governing muscle tissue. They are, a targeted intervention that works with the body’s own architecture by temporarily removing a specific biological brake, in controlled doses, on a single pathway.
This specificity is what gives myostatin inhibitors their safety profile in early trials. Unlike steroids, they do not suppress the body’s endogenous testosterone production, do not disrupt the HPG axis governing reproductive hormones, and do not carry the hepatotoxicity risks of oral androgens. The adverse effects seen so far are generally mild and manageable. The muscle growth is controlled rather than runaway, because the drugs are administered in precise doses and the pathway they target is narrow.
Why This Combination Changes Everything
Every prior weight-loss drug and performance enhancer was a tool that produced a specific effect by overriding a specific system, without addressing the underlying biological architecture that created the problem. The body adapted, the harms accumulated, and the drugs were eventually abandoned.
GLP-1s address the mismatch between our evolved biology and the modern food environment. Our ancestors evolved GLP-1 signaling in a world of caloric scarcity, where that signaling system worked as designed. In a world of caloric abundance, ultra-processed foods engineered to override satiety signals and, sedentary lifestyles that reduce energy expenditure, the natural GLP-1 system is overwhelmed. GLP-1 drugs extend and restore the system’s function in conditions it never evolved to handle.
The same logic applies to the myostatin system. Our bodies evolved to limit muscle mass because maintaining muscle is energetically costly. In a world where food is abundant and the people most at risk from muscle loss are aging adults with sedentary lifestyles, that evolutionary brake is no longer serving its original purpose. Temporarily releasing that brake by selectively inhibiting a single pathway instead of flooding the body with hormones addresses the mismatch directly.
When these two interventions are combined, the result is something genuinely without precedent in the history of medicine. Simultaneous fat loss and muscle gain, achieved by working with, not against, the body’s own regulatory systems. This is not the diet and exercise in a bottle that every previous generation of wonder drugs falsely promised. It is, for the first time, the real thing.
Skepticism Is Warranted — But It Must Be Accurate
None of this means, however, that HOTs are beyond scrutiny. The historical pattern of drug failures establishes a legitimate skepticism, and extraordinary claims require extraordinary evidence. Long-term safety data take time to accumulate and there are still real and ongoing questions about optimal dosing, long-term effects on bone density, the management of muscle loss at higher GLP-1 doses, and the cardiovascular safety profile of newer multi-agonists across diverse populations that deserve rigorous attention.
But skepticism should be applied to the actual mechanism of these drugs, not to the historical pattern they superficially resemble. Calling GLP-1s “just another appetite suppressant” is like calling an electric motor “just another combustion engine” because both make vehicles move. The surface similarity obscures a categorical difference in how the underlying technology works.
The drugs that killed people and wrecked sports for decades were blunt instruments working against biological systems that were stronger than they were. HOTs, at their best, are precision tools that restore and extend biological systems that already exist - they optimize health. That is not a subtle difference.
The skepticism is understandable, but the disruption is real and understanding why these drugs are different from their problematic predecessors is a prerequisite for making good decisions, as patients, as policymakers, as investors, and as a society, about how to navigate what comes next.
This article is part of Rethinking Health, RethinkX’s ongoing series on the Health Optimizer Therapy disruption. RethinkX are experts on global technology disruptions and system change. We are not medical experts. The information in this article is for educational purposes only and does not constitute medical advice.