Stress can absolutely affect weight loss.
But probably not in the simple way social media sometimes makes it sound.
You’ve probably heard about cortisol by now. Cortisol belly. Cortisol weight gain. Lower your cortisol and suddenly everything will fall into place.
I actually think it’s a good thing that people are finally taking stress seriously.
For a long time, weight loss advice could sound a lot like:
Eat less. Move more. Try harder.
As if people live in a vacuum.
They don’t.
They have jobs. Kids. Relationships. Deadlines. Financial stress. Grief. Poor sleep. Full calendars. And days when dinner needs to happen in twelve minutes.
Stress matters. Cortisol matters. But cortisol isn’t the whole story.
What Is Cortisol, Anyway?
Cortisol is one of the hormones involved in our body’s stress response.
Think of the classic example: you’re running from a lion.
Your body doesn’t particularly care about optimizing your meal prep or hitting your fitness goals in that moment. Its priority is helping you respond to what it believes is important right now.
Obviously, most of us aren’t regularly running from lions.
Our stress may look more like a work deadline, an argument, a sick parent, financial problems, too little sleep, five places to be at once, or a phone that never stops making noise.
The stress response itself isn’t bad. We need it.
The problem is that life can keep some people feeling stressed for a very long time.
And that’s where the conversation becomes much bigger than one hormone.
I Think Cortisol Has Become the Simple Explanation for Something Bigger
I understand why cortisol became such a popular health topic.
People want an explanation.
If they’re exhausted, gaining weight, craving sugar, sleeping terribly, and feeling completely overwhelmed, it feels good to have a word for it.
Cortisol.
And there is truth underneath the cortisol conversation. Stress can affect appetite and eating behavior, and cortisol is one part of the body’s stress response.
But that doesn’t mean every person struggling with weight has a “cortisol problem.”
A 2024 study looking at stress, eating behavior, cortisol, and body fat in women with obesity found that women reporting more stress also tended to report more emotional eating and more eating in response to food cues around them. In other words, something looks good, smells good, or is easy to grab, and suddenly it sounds a whole lot better than whatever you had planned. The researchers also found relationships among eating behavior, cortisol, and body composition, although the study can’t tell us that stress or cortisol directly caused someone’s weight gain (Gonçalves et al., 2024).
That nuance matters.
Stress can influence weight in several ways at the same time.
This Is What Stress Looks Like in Real Life
I know what it looks like in mine.
When I’m stressed, I’m more likely to want food that tastes really good and requires very little effort.
Higher-fat, higher-carb foods.
Something processed and quick.
Sugar. Salt.
And if I have things I still need to accomplish, there’s a pretty good chance I’m reaching for more caffeine too.
Sometimes it’s simply what I reach for when I’m stressed. Sometimes I do it often enough that it starts becoming a habit.
That’s not cortisol magically placing fat on my body.
It’s what living under stress can look like in a whole person. My body is responding to stress, and so are my appetite, energy, sleep, habits, and decisions.
I’ve seen the same thing working with other people.
Most People Already Know They’re Supposed to Take Care of Themselves
In my work as a personal trainer, nutritionist, and nurse coach, I rarely met someone who had simply never heard that exercise and nutritious food were good for them.
They knew.
A lot of them were just playing catch-up with their lives.
Work. Kids. Appointments. Dinner. Laundry. Activities. Another thing someone needs from them.
They understood self-care.
The harder part was figuring out how to transform self-care from one more thing they were failing to accomplish into something that actually fit their life.
Sometimes we looked at food.
Some people had never really looked at how much protein, carbohydrate, and fat they were eating or how those choices fit with their goals.
Sometimes the problem was consistency.
Sometimes it was figuring out where a workout could realistically go instead of creating an imaginary workout routine for an imaginary life.
And sometimes we needed to make the healthy choice easier to remember.
Small Habits Matter More Than We Give Them Credit For
This is one reason I like behavior-change approaches that focus on making habits smaller and easier to repeat.
BJ Fogg’s Tiny Habits approach emphasizes starting with behaviors that feel manageable and connecting them with prompts or cues that already exist in your life (Fogg, 2020).
I’ve used that kind of strategy with people.
Instead of:
“I need to completely change how I eat.”
Maybe we start with:
“After I make my coffee, I’ll pack something with protein for later.”
Instead of:
“I need to work out five days a week.”
Maybe we figure out where ten minutes actually fits.
The point isn’t that ten minutes of exercise magically solves everything.
The point is that you’re practicing taking care of yourself inside your actual life.
Then you build from there.
Over time, people started taking back some control of their own lives.
They weren’t becoming people who suddenly had endless free time. They were learning how to stop putting themselves permanently at the bottom of the list.
And that takes time.
Stress Changes the Conditions in Which We Make Decisions
This is probably the biggest thing I want people to understand about stress and weight loss.
When you’re rested, organized, and feeling pretty good, making lunch for tomorrow might not seem very difficult.
When you’re exhausted, overwhelmed, behind on everything, and trying to get three people out the door?
The drive-thru sounds pretty reasonable.
That doesn’t make someone weak.
And it doesn’t mean our choices don’t matter.
It means our environment and our stress level affect how easy or difficult those choices are to make consistently.
That’s why I don’t think telling someone to “just have more discipline” is particularly useful.
I’d rather ask:
What keeps making the choice you want to make so difficult?
Because now we have something we can actually work with.
So Does Stress Stop You From Losing Weight?
Not automatically.
Some people eat more when they’re stressed. Others barely eat. Some stop exercising. Some keep exercising but sleep terribly. Some start living on caffeine and whatever food requires the least thought.
Stress isn’t a switch that turns weight loss off.
It changes the conditions you’re trying to lose weight in.
That’s why I wouldn’t tell someone:
“You can’t lose weight until you fix your cortisol.”
That’s way too simplistic.
I’d say:
“If you’re struggling to make the changes you want to make, stress deserves to be part of the conversation.”
Start With What Stress Is Actually Changing
Instead of immediately buying something that promises to “balance your cortisol,” get curious about your life.
Ask yourself:
What happens to my eating when I’m stressed?
Do I eat more?
Do I skip meals and then get starving later?
Do I want more sugar or salty foods?
Do I order more takeout?
Drink more caffeine?
Stop cooking?
What happens to my movement?
Do workouts disappear because I’m too tired?
Do I sit more?
Could I realistically make movement smaller instead of abandoning it completely?
What happens to my sleep?
And maybe most importantly:
What would make taking care of myself easier right now?
Maybe you need a shorter workout.
Food that’s healthy enough and actually convenient.
A reminder.
A routine attached to something you’re already doing.
Help from somebody else.
A boundary.
More sleep.
A conversation.
Or maybe you need to deal with the actual thing that’s stressing you out instead of trying to wellness-routine your way around it.
The Bottom Line
I’m glad we’re talking about cortisol.
I’m glad we’re talking about stress.
I’m glad we’re getting farther away from pretending weight is simply a measure of somebody’s willpower.
But I don’t think the answer is reducing the whole conversation to one hormone either.
Stress affects the whole person.
Our bodies. Our thoughts. Our sleep. Our appetites. Our energy. Our habits. Our ability to follow through.
So instead of only asking:
“How do I lower my cortisol?”
I think there’s a more useful question:
“What is stress changing about the way I’m living, and what would make the healthier choice easier to repeat?”
That’s where I’d start.
References
Fogg, B. J. (2020). Tiny habits: The small changes that change everything. Houghton Mifflin Harcourt.
Gonçalves, I. da S. A., Filgueiras, M. D. S., Moreira, T. R., Thomé, M. S., Paiva, G. L. D., Almeida, G. P. de, Cotta, R. M. M., Campos, T. do N., Freitas, D. M. de O., Novaes, J. F. de, Oliveira, A. F. de, & Costa, G. D. da. (2024). Interrelation of stress, eating behavior, and body adiposity in women with obesity: Do emotions matter? Nutrients, 16(23), 4133. https://doi.org/10.3390/nu16234133
