One of the things I find myself explaining to women repeatedly is that stress needs fuel.
Not in the vague, “make sure you eat enough” way we have all heard before. I mean it quite literally: a body trying to manage pain, poor sleep, a demanding job, exercise, inflammation, hormone changes or a full emotional load has to get energy from somewhere.
Many of the women I work with do not think they are under-eating. They often eat what looks like a very healthy diet. They have cut down on sugar, avoid dairy and gluten, and are often trying not to snack. Many of them intermittently fast because they’d heard on social media it’s good for metabolism or weight. Other women are simply relying on coffee for breakfast because food feels unappealing.
Then the day gets away from them. Lunch is small, late, or eaten while answering emails. They keep going because they have to. By late afternoon, they can feel foggy, irritable, tired and overwhelmed by relatively ordinary decisions, or are suddenly desperate for some chocolate.
And then there is the sleep. A lot of these women are exhausted, yet can’t properly switch off. Some get to sleep easily enough, only to wake in the early hours with a busy mind, a pounding heart, a sense of dread – often for no obvious reason. By morning they wake up unrefreshed, and the thought of breakfast can make them feel slightly nauseous.
Each of these symptoms can have many drivers. But when they arrive together, I start looking at the gap between what the body is being asked to do and what it is actually being given to do it.
Because sometimes the issue is not that the body is “bad at handling stress”. It’s that it has been trying to carry too much on too little fuel.
What happens when you go too long without enough food?
This is the part I want women to understand: your body will always find a way to keep you going.
There is no alarm that sounds at 11 am because breakfast was too small, or at 3 pm because lunch did not quite cover what your day has required. You can still sit in the meeting, collect the children, finish the workout, answer the emails and make dinner. From the outside, you may look as though you are coping perfectly well.
Inside, though, your body is having to make up the difference.
Between meals and overnight, the liver releases stored carbohydrate, known as glycogen, to keep glucose available for your brain and body. This is one of the body’s normal protective systems. But if food has been thin on the ground for longer than usual, glycogen stores may not be enough to comfortably bridge the gap. The body can then make glucose from other sources and call on hormones such as adrenaline and cortisol to help keep fuel moving.
Again, this is protective. But when it becomes a regular pattern, it can come at a cost. Adrenaline and cortisol are designed to help you respond to a demand, not to prop you up through every under-fuelled afternoon or carry you through the night. Over time, this can leave you feeling more wired, more reliant on coffee, less settled around food and more likely to experience the afternoon crash, sugar cravings, shallow sleep or 3 am waking that seem to arrive without explanation.
The issue is not that you have missed one meal. It is what happens when your body has been quietly filling the gap for weeks, months or years.
You can become used to feeling a little shaky before lunch. You can assume the 4 pm craving is a lack of discipline. You can mistake the need for coffee as proof that you are simply not a morning person. You can even think the wired feeling at night means you still have energy left, when it may be that your body has become very good at finding a way to keep you upright.
This is not a body that is broken. It is a body that has adapted brilliantly to the information it has been given. But adaptation is not always the same as thriving, particularly when pain, poor sleep, inflammation, hormonal change or a high mental load are already asking so much of you.
Why this pattern can catch up with you at night
Sleep is often where this pattern becomes impossible to ignore.
You can push through a day when food has been light or delayed. You might not even notice how little you have eaten until the evening, when you are suddenly ravenous, flat or reaching for something sweet. But overnight, when you are not eating for several hours, your body still needs a steady supply of energy.
If glycogen stores are already under pressure from inconsistent intake, a small dinner, regular exercise or a high stress load, the overnight gap can feel less comfortable for the body to manage. This is where the same protective stress response that helped you through the day can begin to interfere with sleep.
Instead of remaining deeply settled, you may wake suddenly alert, hot, anxious, hungry or shaky, with your mind already racing through tomorrow’s to-do list. Some women wake around 2 or 3 am and cannot settle again. Others wake feeling strangely depleted, dizzy, nauseous or shaky in the morning, even when they have slept for enough hours on paper.
Early waking has many possible drivers, including hormones, pain, anxiety, alcohol, sleep disorders and medication. But when it sits alongside long gaps between meals, afternoon crashes, a strong pull towards sugar or coffee, and very little appetite in the morning, it is a pattern worth paying attention to.
Why you can be exhausted but still not feel hungry
One of the most confusing parts of this pattern is that you may not feel hungry in the way you expect. You may wake tired, slightly nauseous or unable to imagine eating breakfast. You may get through the morning on coffee and only realise you are hungry when you are suddenly irritable, shaky or starving later in the day.
Stress can blunt appetite. It can also change the way the digestive system behaves, affecting motility, digestive secretions and the blood flow available to the gut. That is why, when you are stressed or exhausted, food can feel heavy, sit in your stomach, trigger nausea or simply fail to appeal – even when your body would benefit from more consistent nourishment.
Pain, poor sleep, anxiety, medication, gut symptoms and the habit of overriding hunger can all add to this. It is easy to read a quiet appetite as evidence that you do not need much food. In practice, it can be a sign that your body has been running in a heightened state for so long that its usual signals have become harder to hear.
Why intermittent fasting is not right for every woman
This is one reason I am cautious about the way intermittent fasting is often sold to women.
For some people, a shorter eating window may be a neutral or helpful structure. But the message online is often far more sweeping: skip breakfast, eat less often, and your metabolism, weight, inflammation and hormones will all fall into place. That is often not how it works clinically.
Much of the earlier fasting research has been done in men, animals or mixed groups, and we still have far less clarity about what different fasting patterns mean for women across the menstrual cycle, perimenopause, fertility treatment, chronic pain, thyroid conditions or periods of high stress. The research that does include women is not a reason to dismiss fasting entirely; it is a reason to be more thoughtful about who it suits and when.
The woman who feels well, sleeps well, has a stable relationship with food and can easily meet her nutritional needs is a very different person from the woman who is already tired but wired, waking overnight, training hard, missing periods, managing pain or trying to hold together a demanding life on too little food.
In the latter situation, extending the gap between meals can add another stressor to a system that is already stretched. It can make it harder to eat enough overall, can worsen afternoon crashes and cravings, and can leave the body relying more heavily on stress hormones to bridge the gap.
There are also situations, including insulin resistance or PCOS, where meal timing may form part of a broader plan. But even then, I am more interested in whether a pattern is genuinely supporting energy, symptoms, sleep and metabolic health than whether it looks disciplined on paper.
Will eating more make you gain weight?
This is often the question underneath every conversation about food. If you have spent years being told that weight is simply about eating less and moving more, the thought of eating more can feel frightening. Even a small change on the scale can make it feel as though you have done something wrong.
This is important to understand, particularly when you have been eating lightly or restricting carbohydrates. Your body stores carbohydrate as glycogen in the liver and muscles, and glycogen is stored alongside water. When you begin eating more consistently, those lower stores are replenished. The scale may move slightly as your body restores fuel and fluid, but that is very different from suddenly gaining body fat.
That short-term shift can be enough to make women pull back again, skip the snack, reduce carbohydrates or return to a stricter routine. Yet the pattern they return to may be the same one leaving them shaky, exhausted, preoccupied with food, unable to sleep or reliant on coffee to function.
Keeping intake as low as possible is rarely a sustainable way to support weight or metabolism. Chronic under-eating can make training harder to recover from, increase the urge to overeat later in the day, and leave you with less capacity to make decisions that feel steady and supportive.
The aim is not to abandon your health or weight goals. It is to recognise that a body that feels adequately fuelled is often in a far better position to regulate appetite, energy and recovery than one that is constantly trying to make do with less.
Why this matters even more when you already have complex symptoms
Many women come to me with a body that is already working incredibly hard. You may be managing endometriosis or pelvic pain, difficult periods, PMDD, fatigue, insomnia, thyroid symptoms, fertility challenges, histamine issues, POTS or gut symptoms – often more than one at a time.
Pain takes energy. Poor sleep changes how much you can cope with. Nausea, bloating and food reactions can make eating feel like another job on an already impossible list. Trying to conceive can make food feel so important that every meal becomes a decision you can get wrong.
Then, on top of all of that, you may be trying to lose weight, delaying breakfast, avoiding snacks, restricting carbohydrates or following a narrower and narrower list of “safe” foods.
When there is not enough fuel coming in, the effects do not stay neatly contained to one system. Period symptoms can feel harder to manage. Pain can feel louder. Sleep can become lighter. Energy and mood can become less reliable. Thyroid symptoms can feel more pronounced, and the body’s stress-response system may have to work harder to keep you going – showing up as caffeine reliance, shakiness, afternoon crashes or that frustrating experience of being exhausted but unable to switch off.
This is why I do not look at a difficult period, a thyroid result, an afternoon crash or a poor night’s sleep in isolation. Symptoms are real, and they are clues. The same symptom can have many drivers, but food intake, stress, sleep, pain and hormones are constantly speaking to one another.
If you are generally a stressed person – whether that stress comes from your health, work, caring responsibilities, trauma, exercise or simply the pace of your life – less is not automatically better. Eating less, delaying meals further or narrowing your food choices may feel like control, but it can leave your body with fewer resources to manage everything else it is carrying.
What does eating enough actually look like?
There is no single number that is right for every woman, and I would not reduce this to a generic meal plan. Your needs change with body size, activity, menstrual cycle, life stage, symptoms, medication, stress and what your digestion can comfortably manage.
But it does mean looking beyond whether food is “clean” or whether you have avoided snacks. Protein is important, but it is only one part of the picture. Carbohydrate is not a reward for exercise or something to earn at the end of the day; it is a primary fuel source for the brain, muscles and nervous system.
As a broad starting point, many light to moderately active women do well somewhere around 1.0-1.5g of protein/kg of body weight each day, with carbohydrate needs often sitting well above what diet culture suggests. Those needs rise with training, a physically demanding life, poor sleep, recovery from illness or a high stress load. The right amount is individual, but the bigger question is whether your food is meeting the life your body is actually being asked to live.
For women who are repeatedly waking overnight, eating lightly through the day or going a long time between dinner and bed, a small snack containing carbohydrate and protein before bed can be a useful experiment. The aim is not to treat every sleep problem with food. It is to give your body one less reason to stay on alert while you sleep.
The Bigger Picture
If you are tired but wired, waking overnight, not hungry in the morning or relying on coffee to get through the day, the answer is not always another supplement, stricter diet or more discipline.
Sometimes the more useful question is whether your body has enough consistent fuel for the stress, pain, hormones and demands it is already managing.
If disrupted sleep is showing up alongside fatigue, difficult periods, thyroid symptoms, gut issues or a body that no longer seems to respond to the things that once worked, this is the kind of pattern I look at in consultation.
If you’d like help understanding what may be driving your symptoms, you can book a consultation with me here.
Warmm regards,
References
- Allaway, H. C. M., Southmayd, E. A., & De Souza, M. J. (2016). The physiology of functional hypothalamic amenorrhea associated with energy deficiency in exercising women and in women with anorexia nervosa. Hormone Molecular Biology and Clinical Investigation, 25(2), 91–119. https://doi.org/10.1515/hmbci-2015-0053
- Konturek, P. C., Brzozowski, T., & Konturek, S. J. (2011). Stress and the gut: Pathophysiology, clinical consequences, diagnostic approach and treatment options. Journal of Physiology and Pharmacology, 62(6), 591–599.
- Lowe, D. A., Wu, N., Rohdin-Bibby, L., Moore, A. H., Kelly, N., Liu, Y. E., Philip, E., Vittinghoff, E., Heymsfield, S. B., Olgin, J. E., Shepherd, J. A., & Weiss, E. J. (2020). Effects of time-restricted eating on weight loss and other metabolic parameters in women and men with overweight and obesity: The TREAT randomized clinical trial. JAMA Internal Medicine, 180(11), 1491–1499. https://doi.org/10.1001/jamainternmed.2020.4153
- Mao, L., Liu, A., & Zhang, X. (2024). Effects of intermittent fasting on female reproductive function: A review of animal and human studies. Current Nutrition Reports, 13(4), 786–799. https://doi.org/10.1007/s13668-024-00569-1
