If you’re in your 40s (or even late 30s) and feel like your energy has fallen off a cliff, you’re not imagining it. Perimenopause can make women feel tired in a way that’s hard to explain, even when you’re “doing all the right things”.
The frustrating bit is that tiredness during perimenopause is rarely caused by just one thing. It’s usually a mix of shifting hormones, sleep disruption, stress load, blood sugar dips, and sometimes straightforward nutrient issues like low iron or B12.
Below, I’ll talk you through the most common reasons you might be exhausted, and the nutrition and lifestyle steps that often make the biggest difference (without turning your life into a full-time wellness project).
“Why do I feel like I’ve hit a wall all of a sudden?”
Perimenopause is the transitional stage before menopause, when hormones (particularly oestrogen and progesterone) fluctuate rather than gently decline in a straight line. Those fluctuations can affect energy in a few key ways:
- Sleep and body temperature regulation: changes in oestrogen can contribute to night sweats and disrupted sleep.
- Mood, motivation and resilience: hormones influence brain chemicals like serotonin and GABA, which can affect how calm (or wired) you feel.
- Muscle and metabolic changes over time: as we move through our 40s and 50s, we naturally become a little less insulin sensitive and can lose muscle more easily, especially if protein intake and strength training are low. That can show up as fatigue, brain fog and that “I’m running on fumes” feeling.
It’s also worth saying clearly: perimenopause often lands during the busiest life stage, careers, teenagers, ageing parents, relationships, less time, more responsibility. So even when hormones are the spark, life load is often the fuel.
For a deeper dive into what to eat to support energy and hormone balance, I’d start here: menopause nutrition: what to eat for energy, weight and hormone balance.
“Is it my hormones, or am I just not sleeping properly?”
Sleep is one of the biggest drivers of perimenopause fatigue, and it’s also the most underestimated.
Even if you’re in bed for 8 hours, you might not be getting the deep, restorative sleep your brain and body need if you’re waking at 2–4am, overheating, or lying there with a busy mind.
A few common sleep disruptors in perimenopause:
“I wake up at 3am and I can’t get back to sleep”
This pattern is incredibly common. It can be related to stress hormones (cortisol), blood sugar dips overnight, alcohol, or simply hormonal shifts.
Nutrition-wise, it can help to look at:
- Caffeine timing: for many women in perimenopause, coffee after late morning can start to affect sleep quality.
- Alcohol: it may help you fall asleep, but it often reduces sleep quality and increases night waking.
- Dinner balance: very light dinners, or dinners that are mostly carbs without protein and fats, can leave some women more prone to a blood sugar dip overnight.
“I’m shattered, but wired”
That wired-tired feeling often points to stress physiology and nervous system overload. This is where food can support you, but the biggest wins often come from basic anchors: daylight in the morning, movement, protein earlier in the day, and calming down your evenings.
If you want a reputable overview of perimenopause symptoms (including sleep changes), the NHS perimenopause page is a useful starting point.
“I’m eating ‘healthy’… so why do I feel so drained?”
This is one I see a lot. Women often clean up their diet in their 40s, but accidentally under-fuel.
Common patterns that backfire in perimenopause:
- Skipping breakfast (or having something very light like toast or fruit)
- Having a low-protein lunch (salad without a proper protein portion)
- Trying to be ‘good’ all day, then hitting cravings, snacking in the evening, and blaming “willpower”
Perimenopause is not the time for punishing restriction. Your body usually does better with steady, consistent nourishment.
The “energy plate” that tends to work best
Most women do well when meals include:
- Protein (eggs, Greek yoghurt, fish, chicken, tofu, lentils)
- Fibre-rich carbs and colour (veg, beans, wholegrains, berries)
- Healthy fats (olive oil, nuts, seeds, avocado)
This combination supports more stable blood sugar, better satiety, and often fewer afternoon slumps.
If you’re unsure how much protein you actually need, Tracey has a helpful tool here: How Much Protein Do You Need? (protein calculator).
“Is my blood sugar playing a part in this tiredness?”
Blood sugar swings are a very common (and fixable) cause of fatigue in perimenopause.
When blood sugar rises quickly and then drops quickly, you can feel:
- sleepy after meals
- shaky, light-headed, or irritable when you haven’t eaten
- drawn to sugary snacks at 3pm
- more anxious or “on edge”
Perimenopause can make this worse because hormone changes can reduce insulin sensitivity for some women, meaning your body may not handle refined carbs quite as smoothly as it used to.
A simple place to start is breakfast. If you currently have cereal, toast, or a smoothie that’s mostly fruit, try swapping to a higher-protein option for a week and see what changes.
Here are a few examples that are realistic (not perfect):
- Greek yoghurt with berries, nuts and seeds
- Eggs with veg and sourdough, or leftovers from dinner
- Porridge made with milk or soy milk, plus protein (Greek yoghurt stirred in, or a scoop of protein powder) and seeds
If you want more practical ideas specifically for menopause energy and weight, the guide I linked earlier is the best next step: what to eat for energy, weight and hormone balance.
“Do I need to check my iron, B12, thyroid, or vitamin D?”
Sometimes perimenopause fatigue is made worse by something that’s not “just hormones”. It can be worth speaking to your GP about symptoms and asking whether blood tests are appropriate.
This is especially important if fatigue is new for you, worsening, or affecting day-to-day life.
Here’s a helpful overview of common fatigue-related nutrients and markers to consider.
| Possible factor | Why it matters for energy in perimenopause | Food-first support | Consider asking your GP about |
|---|---|---|---|
| Iron (and ferritin, iron stores) | Low iron can contribute to tiredness, breathlessness, poor exercise tolerance and feeling wiped out | Red meat, lentils, beans, spinach, pumpkin seeds, plus vitamin C with meals | Ferritin, full blood count, iron studies |
| Vitamin B12 | Important for red blood cells and nervous system function | Animal foods (meat, fish, eggs, dairy) or fortified foods if plant-based | B12 (and sometimes folate) |
| Thyroid function | Underactive thyroid can mimic perimenopause symptoms, fatigue, weight changes, low mood | Selenium and iodine-rich foods may support thyroid health, but testing matters | TSH (and sometimes free T4) |
| Vitamin D | Low levels are common in the UK and can affect mood, immunity and muscle function | Oily fish, eggs, fortified foods, sensible sunlight | Vitamin D level |
| Blood sugar control | Poor glucose regulation can cause slumps and cravings | Balanced meals, fibre, protein, regular eating | HbA1c (especially with family history) |
If you’d like to read more on nutritional causes of low energy, this post may also be helpful: Why Am I So Tired? 7 Nutritional Reasons Your Energy Is Low.
For evidence-based menopause guidance, the NICE menopause guideline (NG23) is a solid reference point to discuss options with your healthcare professional.
“Could stress be the real reason I’m exhausted?”
Stress is not just a mindset issue, it has real physiological effects. When you’re under chronic stress, your body prioritises survival hormones. That can affect:
- sleep quality
- appetite and cravings
- digestion (bloating, reflux, IBS-type symptoms)
- motivation to cook, exercise, or make good choices
In perimenopause, this can feel amplified, because your usual stress tolerance may feel lower.
Two gentle approaches I often suggest (because they’re doable):
Eat in a way that signals safety to the body
That usually means:
- regular meals (especially earlier in the day)
- enough protein
- not running on caffeine and adrenaline
Build one “downshift” into your day
It can be 5 minutes. A short walk outside after lunch, a breath practice while the kettle boils, stretching before bed. The goal is not another task, it’s sending your nervous system the message that you’re not in constant go-mode.
“What can I actually do this week that will help?”
If you’re overwhelmed, start with a 7-day experiment. Keep it simple and track how you feel (energy, mood, sleep, cravings). Here’s a structure that works for many women.
| Time of day | What to do | Why it may help |
|---|---|---|
| Morning | Eat protein at breakfast (or within 1 hour of waking if you can) | Supports steadier blood sugar and energy, often reduces cravings later |
| Midday | Build a balanced plate (protein + fibre/colour + healthy fat) | Improves satiety and reduces the afternoon slump |
| Afternoon | Hydrate and plan a proper snack if needed (not just a biscuit with tea) | Dehydration and under-fuelling can feel like fatigue |
| Evening | Keep caffeine earlier, go easy on alcohol if sleep is fragile | Both can disrupt sleep quality and overnight recovery |
| Before bed | Magnesium-rich foods (and discuss supplements if appropriate), dim lights earlier, aim for a consistent bedtime | Helps your body wind down and supports sleep routines |
Hydration is easily missed, and it genuinely matters. If you suspect you’re not drinking enough, you might like: Hydrate for Hormonal Harmony: The Importance of Water in Menopause Management.
And if you’re considering supplements, quality and suitability really matter (especially if you take medication or have a health condition). You can browse Tracey’s general resources here: useful links and recommended resources.
“When is tiredness a sign I should get checked out?”
Perimenopause can absolutely cause fatigue, but you don’t need to brush everything off as “just hormones”. Please speak to your GP if you have fatigue with any of the following:
- breathlessness, chest pain, fainting, or heart palpitations that feel new or worrying
- significant or unexplained weight loss
- very heavy bleeding, bleeding between periods, or bleeding after sex
- persistent low mood, anxiety, or feeling unable to cope
- fatigue that is rapidly worsening, or stopping you from functioning day to day
If you’re also considering HRT or other medical options, it can be helpful to explore these alongside nutrition support. The British Menopause Society has reliable information that many women find reassuring.
If you’re thinking “I just want my energy back”, you don’t have to figure it out alone
Perimenopause tiredness is real, and it can be improved, but it often takes a personalised approach. What helps one woman might not help the next, especially if digestion, stress, sleep, iron levels, or blood sugar are part of the picture.
If you’re searching for a women’s health nutritionist near me in Cheshire (or you’d prefer online support), I offer a free 15-minute consultation so we can chat through what’s going on and what support would feel most helpful. You can book from Nantwich and across the local area, including Crewe, Chester, Sandbach, Northwich, Congleton, Wilmslow and beyond, and I also work with clients nationwide by video.
When you’re ready, you’re very welcome to get in touch and book your free call.
