What Obesity Drugs and Antidepressants Have in Common
Dr. Carroll is the chief health officer of Indiana University and writes often on
Sign up for the Opinion Today newsletter Get expert analysis of the news
and a guide to the big ideas shaping the world every weekday morning.
We like to think we understand the drugs we take, especially after rigorous
trials have proved their efficacy and safety. But sometimes, we know only
that medications work; we just don’t know why.
Recently, I’ve faced this conundrum regarding drugs for mental health
conditions and obesity, two heavily stigmatized health issues with causes
and treatments that science doesn’t fully comprehend.
Until a few years ago, I had controlled my depression and anxiety through
decades of counseling. I was reluctant to try medications because the
medical understanding of them seemed vague. For instance, we know that
selective serotonin reuptake inhibitors, or S.S.R.I.s, leave more serotonin
floating around your neurons in your brain, but we don’t fully understand
how or why that makes a difference. We also can’t explain why some people
benefit from S.S.R.I.s and others do not. Because of this, many people still
believe those who take them don’t really need them.
I also believed that, if I was strong enough, I didn’t need medication. But in
2021, when I was under a substantial amount of stress, I had a panic attack
on vacation and fell partway down a mountain. I was airlifted to a hospital,
alarming my wife and friends. It was clear I wasn’t OK.
My physician recommended sertraline, an older but widely used S.S.R.I.
While I was skeptical that it would make a difference, I tried it.
I was wrong to doubt. It’s had a remarkable effect on my mood, and almost
everyone around me noticed the difference. I was more optimistic, friendlier
and more engaging. I was forced to reconsider why I had avoided taking the
medication for so long. I think it’s because — even though I realize this isn’t
true — taking it felt like an admission of failure.
Because I didn’t know the exact mechanism that caused my anxiety to be
uncontrollable (and no one else did either), it seemed as if I must be
cheating to use a drug that greatly helped my situation. It felt like a crutch or
a shortcut. Especially because, even as a doctor, I can’t explain why the
medication works for me or anyone else.
I’ve recently faced a similar scenario with new drugs for obesity. I’ve
struggled with my weight for most of my life. I’ve always been overweight,
and in the last few years, I’ve slipped into obesity, according to my body
mass index. I exercise regularly and carry the weight well, but it bothers me
immensely. It especially troubles me because I have a fair amount of self-
discipline and eat quite healthfully.
Though I’ve tried every diet, nothing has really helped. I’d lose up to 10
pounds and then plateau until my weight crept back up.
Because I am so careful about what I eat, my weight has not yet led to any
other health consequences. But I know what could happen if I stop being
mindful. My father was morbidly obese. It led to a lower quality of life and
mental health issues and probably contributed to his death a few years ago.
Despite all the advances in science, we don’t know why some people, even
when they try desperately, can’t seem to lose weight. Because of that, we
often assume it must be a lack of willpower. I begged my father, who was
also a physician, to lose weight, and he never could. In the back of my mind,
I, like many others, blamed him for his failures and considered it a lack of
I blamed myself, too. I became so disheartened at my inability to affect my
weight that it harmed my mental health. I felt like a failure, which led to self-
hatred and anger.
Five weeks ago, I went on a walk with a friend who had just lost a younger
brother to heart disease. It was a reminder that time is limited and I should
make use of it more wisely. I asked my doctor to write me a prescription for
one of the new injectable obesity drugs. He warned me that it was approved
at this time only for people with diabetes, and since I didn’t suffer from that,
this would be off-label use and wouldn’t be covered by insurance. These
drugs are expensive, but I was determined to see what would happen if I
It is hard to explain what life is like on this medication to people who don’t
have trouble controlling their weight. I’m not hungry all the time. I’m not
thinking about food incessantly. I’m not obsessing about what I wish I could
eat and what I can’t. My mental health, and even my temperament, improved
so much that my whole family rejoiced.
I’ve lost 15 pounds in the last five weeks, and I’ve done it with ease. It can’t
just be because I’m eating much less, because I haven’t reduced my caloric
intake that much. But like everyone else, including scientists, I have no idea
why these drugs work so well.
Before writing this essay, I had told just a few people I’m on the drug. I think
it’s because, on some level, I still feel shame. I felt the same when I finally
started taking an antidepressant.
Mental health disorders and obesity fall into a bucket of diagnoses that, amid
a lack of complete knowledge of their causes, are subject to societal
moralizing and stigma. We make assumptions that people with depression
aren’t trying hard enough, that people with obesity lack willpower. These
stigmas are then compounded by a limited understanding of how their
treatments work, leading to further judgments of people who seek them.
This is especially true if there’s no clear endpoint for treatment. I’ve heard so
many thoughtful people argue against using these injectable drugs for
weight loss because “people often regain the weight if they stop taking
them.” Of course they do. Something is off balance with them that these
drugs are correcting. We don’t know what it is, but the drugs are
compensating for it, not curing people permanently.
As I’ve written before, I’ve had ulcerative colitis for almost 30 years. The
medication I take to keep me in remission has a small, but greater than zero,
chance of shutting down my blood marrow, yet the upsides are hard to
overemphasize. I will be on that drug for the rest of my life. I’m OK with that,
and no one, including me, has ever questioned if it’s a good idea to take it
because I’ll never be able to quit.
We don’t assume that people with Type 1 diabetes who need to be on
insulin, or people on thyroid medication, should have to stop. There are many
other examples of conditions whose sufferers must undergo treatments for
decades or more.
The mechanisms for those diseases and disorders are usually better
understood, though; they fix problems we’ve mapped out pretty clearly and
are not perceived as being the result of a personal deficiency. It’s when
there’s doubt and stigma that we question the need and the longevity.
I’m sure these obesity drugs won’t work for everyone — they won’t
overcome bad eating habits or many other issues. I am also aware that we
don’t know their long-term effects. Most important, I know I’m privileged
that I can afford to pay for them out of pocket.
What we should focus on is their potential to improve lives significantly,
much as they have for me. Medical treatments should not be dismissed just
because we don’t fully grasp their mechanisms; people who use them are