Perimenopause, ADHD, and Cortisol, Why stress can change your body shape
Over the past couple of years, I have noticed a pattern in many women in perimenopause, including in my own body, a change in body shape that seems to happen even when nothing obvious has changed.
You are not suddenly eating very differently, and you may still be exercising regularly, yet your tummy gets bigger and looks and feels horrible. Nothing you do seems to help get rid of it, which is deeply frustrating and can become another reason to feel rubbish about yourself.
This is not a willpower issue. For many women, it is a stress system issue, specifically a cortisol and HPA axis issue.
Cortisol is your body’s main stress hormone, and it is regulated by the HPA axis, the hypothalamic–pituitary–adrenal axis. This is the communication pathway between your brain and your adrenal glands that decides how much stress your body thinks it is under, and how strongly it needs to respond. When the HPA axis detects threat or pressure, whether physical, emotional, or cognitive, it tells the body to release cortisol to help you cope.
In short bursts, this system is helpful and protective. It helps you wake up, focus, react, and get through challenges. The problem is not cortisol itself, but what happens when this system is switched on too often and does not get enough chance to switch off again.
This is where ADHD and perimenopause become a particularly difficult combination.
ADHD brains tend to live with higher baseline levels of stress. Many women with ADHD spend years compensating, masking, overthinking, rushing, firefighting, and using huge amounts of mental energy just to keep daily life on track. Even when things look calm on the outside, the internal experience is often one of pressure, urgency, and cognitive overload. This means the HPA axis is activated more frequently and more intensely, and cortisol is released more often throughout the day.
Perimenopause then changes the picture again. Oestrogen plays an important role in regulating the stress response and supporting the brain’s ability to cope with pressure. As oestrogen fluctuates and declines, the stress system becomes more reactive and less well buffered. In simple terms, the same amount of stress now produces a bigger physiological response.
When you combine a brain that already runs “hot” with a hormonal system that is becoming less protective, the result is a stress response that is more easily triggered, stays switched on for longer, and is harder to settle. Over time, this leads to chronically elevated cortisol levels for many women with ADHD in perimenopause.
When cortisol stays elevated, the body moves into a more protective, survival-focused mode. One of the ways it does this is by storing more fat around the abdomen, because this is the most accessible energy reserve in an emergency. This is not a flaw or a failure, it is the body doing exactly what it is designed to do when it believes the world is unsafe and unpredictable.
This is why so many women notice that their shape changes in perimenopause even when their eating or activity levels have not significantly changed, and why simply trying to eat less or exercise more often does not reliably work. If the HPA axis is still reading life as “too much”, the body will continue to protect itself.
What actually helps, then, is not fighting the body, but changing the message the stress system is receiving.
When the HPA axis is supported to become less reactive and cortisol levels begin to settle, the body often becomes more willing to rebalance. This is not quick and it is not about control, but it is about creating more physiological safety. In practice, this usually starts with protecting sleep, reducing constant overload and urgency where possible, and being far more realistic and compassionate about what your brain and body are carrying in this phase of life.
None of this is about forcing your body into a different shape. It is about supporting a stressed system in a hormonally changing body.
If you are noticing these changes in yourself, please know that your body is not failing you. It is responding in a very human way to prolonged stress and hormonal change, and that deserves understanding rather than blame.
Further reading and useful resources
McEwen, B. S. Stress, adaptation, and disease, allostasis and allostatic load
Harvard Health, Understanding cortisol and the stress response
British Menopause Society, Perimenopause and the impact of hormonal change
Mosconi, L. The Menopause Brain
Newson, L. Hormones, stress and midlife health