You haven’t changed what you eat, or you don’t think you have. You’ve been working late, sleeping five hours, and the walks stopped in September. The trousers that fitted in July don’t. Someone online says it’s “cortisol belly”. Is it?
Stress can contribute to weight gain, but mostly indirectly: it changes how you eat, sleep and move, and the direct effect of stress hormones such as cortisol is small for most people. If you’re gaining weight without changing anything, or can’t lose it whatever you try, see a doctor, because an underactive thyroid, PCOS, some medicines and several other conditions are more likely explanations than stress alone. Our guide to stress in Nigeria explains stress itself. This piece is about your weight.
See a doctor first if your weight is going up along with any of these: swollen feet or ankles, or getting breathless (a fast gain with swelling can be fluid, which can be dangerous); feeling cold, very tired and constipated, with dry skin or hair loss; fat building up on your tummy, neck and upper back with a red, round face, easy bruising, stretch marks or weak muscles; irregular or stopped periods with extra hair growth or acne; a hunger you can’t control with a racing heart, shaking and sweating; or changes in your vision. If you’re pregnant or gave birth in the last few weeks and get sudden swelling of the face, hands or feet, a severe headache or vision problems, get urgent help from your maternity unit or a hospital. If you have chest pain or can’t catch your breath, call 112 now (or 767 in Lagos).
How stress affects your weight
A meta-analysis pooled 14 long-term studies that followed people over time. Most of the individual analyses found no clear link between stress and weight gain. Pooled together, stress did predict a little more gain over time, and the authors concluded it is a risk factor whose effects are “very small”. For most people, stress is a small part of the story. Where it matters, it works through three routes.
Eating
Stress changes appetite in both directions. The World Health Organization says stressed people may lose their appetite or eat more than usual, and the NHS lists eating too much or too little among the behaviour changes stress causes. For the people who eat more, a 2022 meta-analysis of 54 studies found stress was linked with eating more unhealthy food and less healthy food, though the average effect was small. Long days without meals, then one big late dinner, make it worse. Our guide to emotional eating covers this route in full.
Sleep
Stress often disturbs sleep, and short sleep is linked with weight gain: in a meta-analysis of long-term studies covering nearly 200,000 people, those who slept too little were more likely to develop obesity later. Trials where researchers shortened people’s sleep on purpose found it tended to increase hunger, appetite, portion sizes and how often people ate. If stress is keeping you up until 2am, our guide to insomnia is worth reading before anything about food.
Movement
Stress makes most people move less. A review of 168 studies found that in about three in four of the long-term ones, stress predicted less physical activity or more sitting. A minority of people exercise more when stressed, and people who already exercised regularly tended to keep going. If the gym, the evening walk or the Saturday football stopped when work got heavy, that’s part of your answer.
What about cortisol?
Cortisol is one of the hormones your body releases under stress, alongside adrenaline. It’s real, and too much of it does cause weight gain. That happens in Cushing’s syndrome, which the NHS describes as rare. People with it build up fat on the neck, upper back, chest and tummy, often with thin arms and legs, a red, round face, easy bruising and stretch marks. It’s most often caused by medicines taken for a long time for other conditions, and sometimes by a small growth on a gland. A doctor can test for it with a blood, urine or saliva sample.
Everyday stress is not Cushing’s syndrome. The research on ordinary cortisol and weight is mixed. A 2022 meta-analysis of 146 groups of people found that higher long-term cortisol, measured in hair, went with a larger waist and a heavier weight for height, but the link was modest, and because those studies measured both at one moment, they can’t show which caused which. Another review found no link between body fat and the morning rise in cortisol.
The evidence that everyday stress gives you a “cortisol belly” is thin. If someone sells you a tea or a supplement to fix it, read our guide to slimming tea side effects first.
Suggested read: Can Stress Cause Hair Loss? Shedding, Edges and Grey Hair
Why can’t I lose weight?
If you’ve been trying for months with nothing to show for it, the reason may have nothing to do with willpower, or with stress. The NHS and MedlinePlus list these, among others:
- An underactive thyroid. Tiredness, feeling cold, weight gain, constipation, low mood and dry skin, coming on slowly. A blood test can check.
- PCOS. The NHS now calls it polyendocrine metabolic ovarian syndrome (PMOS). Its symptoms include weight gain or difficulty losing weight, irregular periods, extra hair, acne, and depression or anxiety. Our post on PCOS and mental health covers the emotional side.
- Medicines. Some medicines for mental health conditions, diabetes and other illnesses can cause weight gain. Don’t stop any of them on your own; ask the doctor who prescribed it.
- Life stages. Pregnancy, perimenopause and menopause, and being over 55.
- Fluid. Heart or kidney problems can cause weight gain from fluid, often with swelling.
- Stopping smoking, which commonly brings some weight gain.
- Depression and eating disorders, which the NHS lists among the things that make weight harder to manage.
- Genes, which make some people more likely to gain weight than others.
The doctor may ask about stress and mood too. MedlinePlus notes that weight gain linked to stress or low mood may need counselling, which is where a therapist comes in.
The pressure to fix it fast
In Nigeria, a gain rarely goes unremarked. “You’ve added” at a family gathering, the wedding photos, the colleague who asks what you’re doing differently. The pressure pushes people towards quick fixes: slimming teas, pills, and lately injections bought from vendors, which our guide to weight loss injections in Nigeria explains.
Crash dieting is a risky answer to stress. The UK’s NICE guideline warns that dieting is likely to trigger binges in people being treated for binge eating, and stress already pushes eating towards the less healthy end.
What helps with the stress part
These won’t fix a thyroid problem or a medicine’s side effect. They’re the steps the research above supports for the stress routes.
- Protect your sleep. The WHO’s advice is a regular bedtime and waking time, a dark, quiet room where you can manage it, and screens away before bed.
- Eat at regular times. The WHO lists regular meals as part of coping with stress. It stops the long-gap, late-feast pattern.
- Keep moving in a way you’ll keep doing. The people who kept exercising through stress were the ones with the habit already. Start small enough that a bad week doesn’t end it.
- Deal with the stress itself. Our guide to stress in Nigeria covers what helps.
When to see a therapist
See a doctor about the weight. See a therapist if stress has lasted weeks, if you’re eating to cope most days, if your mood has dropped, or if shame about your body has you avoiding people and events. A therapist works alongside your doctor, never instead of one, and therapy isn’t a weight-loss treatment. You can find a therapist who works with stress and burnout on Mytherapist.ng, by video, voice or chat.
If eating has started to feel out of control, or you’re making yourself sick, fasting or exercising to make up for food, read our guides to binge eating disorder and recognising an eating disorder in Nigeria, and take the free two-minute screening on our eating disorders page.
If you’re having thoughts of ending your life, call 112 (or 767 in Lagos), or Safe Place Nigeria on 0800 800 2000, free and open 24 hours. The full list is on our helplines page.
Frequently asked questions
Does stress cause weight gain?
It can contribute, but the direct effect is very small for most people. Stress mostly works through eating more and less healthily, sleeping less and moving less. Unexplained weight gain needs a doctor, because thyroid problems, PCOS, some medicines and other conditions are possible causes.
Can cortisol cause belly fat?
Very high cortisol, as in Cushing’s syndrome, does put fat on the tummy, neck and upper back, but that condition is rare. For everyday stress, research shows only a modest link between long-term cortisol and waist size, and it can’t show that one causes the other.
Suggested read: Weight Loss Injections in Nigeria: Ozempic, Mounjaro, Risks
Can lack of sleep make you gain weight?
It’s linked. People who sleep too little are more likely to develop obesity over the years, and trials show shortened sleep increases hunger and how much people eat.
Can stress make you lose weight?
Yes, some people lose their appetite under stress. But losing weight without trying, especially with thirst, tiredness or peeing more than usual, needs a doctor, whatever you think the cause is.
This article is awaiting clinical review. It’s based on published research and health guidelines, and we’ll update it once a clinician has reviewed it.
