There is a version of summer that exists on social media and in the imagination: golden hours, spontaneous plans, long evenings with people you love. And then there is the version many people with endometriosis know. The one where the heat presses down on an already exhausted body. Where the bloating that has been manageable all spring becomes unbearable under a sundress. Where the fatigue is not cured by sunshine but somehow made heavier by it. Where being chronically ill in summer feels like its own particular kind of loneliness.

This piece is for those people. It is also for the people in their lives who want to understand. And it is for anyone who has spent years being told their pain is not real, only to discover that the invisible illness they were carrying had a name, and that they were not imagining any of it.

Endometriosis is a condition in which tissue similar to the lining of the uterus grows outside the womb, on the ovaries, fallopian tubes, bowel, bladder, and sometimes further afield. Each month, this tissue responds to hormonal cycles the way it would inside the uterus: it swells, bleeds, and has nowhere to go. The result is internal inflammation, scarring, and pain that can be debilitating.

But endometriosis is not just a period problem. For many people, symptoms are present throughout the month: pelvic pain that never fully disappears, bowel and bladder symptoms that make certain foods or social situations unpredictable, profound fatigue that does not respond to rest, brain fog that makes concentration feel like wading through wet concrete, and a nervous system that has been on high alert for so long it no longer knows how to switch off.

In summer, several of these symptoms tend to intensify. Heat increases inflammation in the body. Disrupted routines, including holidays, social commitments, and different eating patterns, can destabilise gut health. The expectation that everyone should be energetic and physically active sits in sharp contrast to the reality of living in a body that is doing something very different.

It is not your imagination. There are real physiological reasons why summer worsens the symptoms of endometriosis, and understanding them can help you communicate what is happening to the people around you, including healthcare providers who may not have connected the dots.

Dehydration

Sweating in the heat causes the body to lose fluids and electrolytes faster than most people realise. Even mild dehydration, the kind you might not notice until you have a headache, lowers your pain threshold, thickens the blood, and causes muscle cramping. For someone with endometriosis, whose baseline pain levels are already elevated, this means that a warm day out can push symptoms that were just about tolerable into genuinely difficult territory.

Inflammation

To keep the body cool, blood vessels near the skin dilate. This process causes tissues, ligaments, and tendons around joints to expand, which can press on nerves and intensify pain. High humidity compounds this further, significantly worsening inflammatory responses in the body. For conditions involving chronic inflammation, including endometriosis, this is not a small effect.

Nerve sensitivity

Hot weather dilates blood vessels and lowers blood pressure, which promotes fluid shifts in the body and can irritate nerve endings. For people who already experience nerve-related symptoms, such as burning, tingling, or hypersensitivity, heat can intensify these significantly. This is one reason why some people find that pain changes character in summer, feeling sharper, more electric, or more widespread than usual.

Barometric pressure shifts

Heatwaves frequently coincide with drops in atmospheric pressure. When barometric pressure falls, the fluids and tissues within joints expand slightly, leading to increased stiffness and pain. This is a well-documented phenomenon in conditions affecting joints and connective tissue, and it explains why many people notice their symptoms worsen in the thick, heavy air before a summer storm rather than only in the direct heat.

Endometriosis-related bloating, sometimes called endo belly in patient communities, is not the bloating of eating too many carbs. It is a distinct physiological phenomenon, linked to gut inflammation, bowel involvement of endometriosis, and the hormonal fluctuations that affect the digestive system. For many people, it comes on suddenly. You can go from a flat stomach in the morning to looking visibly pregnant by afternoon.

Summer makes this harder. Lighter clothing. More skin. The cultural pressure to have a beach body, which despite what campaigns say still carries enormous weight. When your abdomen swells unpredictably, the simple act of getting dressed in warm weather becomes a negotiation between comfort and visibility, between what the body needs and what society expects it to look like.

It also intersects with the practicalities of summer. Tight waistbands become unbearable. Sitting for long periods at outdoor picnics, in festivals, or on planes for summer holidays worsens bloating and pain. The foods associated with summer socialising, including alcohol, barbecued meats, and processed foods, are often significant triggers. Navigating a barbecue when your gut is already inflamed requires a level of planning and negotiation that most people never have to think about.

What can help

• Loose, high-waisted clothing that allows for fluctuation without restriction
• Identifying personal food triggers by keeping a diary through spring to help prepare for summer
• Anti-inflammatory dietary approaches: reducing ultra-processed foods, alcohol, and known personal triggers
• Heat therapy for abdominal pain: heat patches or hot water bottles used discreetly at events
• Communicating honestly with people you trust about why you may need to eat differently or leave early

The fatigue of endometriosis is chronic and inflammatory. It is not the tiredness that a good night’s sleep fixes. It is the kind of fatigue that accumulates regardless of rest, that makes decisions feel impossible and social interactions feel like physical labour. Researchers have found that fatigue in endometriosis is significantly linked to the immune system’s constant low-level inflammatory response, the body using enormous energy to manage tissue it cannot clear.

In summer, this fatigue interacts with heat in ways that can be genuinely disabling. The body works harder to regulate its temperature in warm weather, drawing on energy reserves that people with endometriosis simply do not have surplus of. The result is an intensification of fatigue that can feel disproportionate to what is happening externally, and that can be invisible to everyone else, who sees sunshine and assumes energy.

There is also what might be called social fatigue: the exhaustion of explaining, negotiating, performing wellness, and managing other people’s expectations throughout a season that is culturally associated with maximum social participation. Turning down invitations, leaving early, resting instead of attending, all of these require emotional labour that compounds the physical.

Summer is the season that most aggressively demands a relationship with your body. Swimwear. Shorts. The assumption that everyone wants to show skin and feel confident doing it. For people with endometriosis, this cultural moment collides with a physical reality that is often deeply at odds with it.

Bloating that fluctuates without warning. Weight changes caused by hormonal treatments, some of which cause fluid retention and some of which alter appetite or metabolism entirely. Surgical scars from laparoscopies that are still new, or that have faded but have not gone. The physical evidence of medical management, written on a body that summer asks to be uncovered and unashamed.

Research consistently shows that body image and self-concept are significantly affected in people with endometriosis, and that this psychological dimension is often under-addressed in clinical care. The summer context does not create these feelings, but it amplifies them, and at a volume that deserves to be named rather than minimised.

Invisible illness carries a particular social burden in summer because summer is the season of maximum visibility. Bodies are more exposed. Activity is more public. Social calendars are fuller. And the cultural narrative around summer is saturated with the idea that everyone is thriving, or should be.

People with endometriosis often describe a specific kind of summer grief: the gap between the life they imagined and the one they are living. Watching friends post from festivals they could not attend. Making excuses that feel true but insufficient. Sitting in the shade while everyone else swims, and hoping no one asks.

These experiences are not dramatic. They do not belong to a category of suffering that is easy to headline. But they are the texture of chronic illness in summer, and they are real, they are common, and they deserve to be named.

What support actually looks like

• Flexible invitations that do not require early commitment: ‘we would love you there, come if you can’
• Asking what accessibility looks like rather than assuming: rest space, seating, cool environments, dietary options
• Not commenting on what someone is or is not eating, wearing, or doing with their body
• Believing them when they say they need to leave, without requiring justification
• Not projecting: ‘but you seemed fine yesterday’ ignores that chronic illness fluctuates, and appearing well one day does not predict the next

On 15 August, we are hosting our Family Fun Day at Park Community School in Leigh Park. The event runs from 11am to 3pm and is completely free to attend. It is a celebration of community, education, and the kind of open conversation about periods and bodies that we believe every young person deserves access to.

The day brings together something for everyone. There will be children’s activities, vendor stalls, and four panel talks covering medical, community, lifestyle, and fertility themes. These panels give attendees the chance to hear from experts and ask the questions that often go unanswered in a standard appointment.

One of the highlights of the day is a dedicated space for young people to learn about periods and create their own My First Period Box. It is a hands-on, empowering activity designed to give young people the knowledge and the kit to feel prepared and confident rather than caught off guard. Because when young people learn early that significant period pain is not normal, and that their body deserves to be listened to, we reduce that 7-to-10-year diagnostic delay one conversation at a time.

The Family Fun Day is for everyone: people with endometriosis, their families, young people navigating their menstrual health for the first time, and anyone who has ever been told their experience of their body was not valid.

If you have read this piece and recognised yourself in it, the summer grief, the invisible management, the exhaustion of appearing well when you are not, we want you to know that what you are experiencing is real and documented and shared by more people than you might imagine.

If you are yet to receive a diagnosis but something here resonated, please talk to your GP. Keep a symptom diary. Ask for a referral to a gynaecologist with experience in endometriosis. You are not being dramatic. You are not exaggerating. And you deserve care.

If you are supporting someone with endometriosis this summer, the most useful thing you can do is believe them. Not fix things, not minimise, not offer unsolicited advice about diet or attitude. Believe them, and adjust your expectations of what summer together looks like.

And if you are simply in it, managing day by day, making it to the end of a difficult week or a difficult season, that counts. It more than counts.

This blog post was written for the July Awareness Campaign. Medical claims are drawn from peer-reviewed literature. This piece is for informational and advocacy purposes and does not constitute medical advice.