Flagging by 3pm, waking at 2am, and noticing your waistline changing even though your routine hasn't?
It's easy to blame yourself. But midlife metabolism isn't a willpower problem. It's a physiology shift, and what's on your plate plays a bigger role than most people realise.
Calories get all the attention, but your metabolism actually runs on nutrients. Here are the essentials I look at first in clinic, and the ones I always test before reaching for a supplement.
The foundation: protein
If you only change one thing - please make it protein. You know I bang on about protein in nearly every single blog post. That's because it's the one macronutrient I see women tend to under-fuel on when I'm looking at a client's food diary. From our mid-30s we gradually lose muscle, and muscle is your metabolic engine. It's where much of your blood sugar gets used, and it helps keep bones strong as oestrogen declines.
Research generally points to around 1.0 to 1.2 g of protein per kilo of body weight each day for midlife women, a little more if you're strength training. For a 70 kg woman, that's roughly 70 to 85 g, spread across your meals. (If you have kidney disease, check with your health professional first.)
Pair it with resistance training and you're protecting the very tissue that keeps your metabolism humming.
The metabolic cofactors
Think of these as the spark plugs. They don't "boost" your metabolism, but when you're running low, things simply don't work as well as they should.
Magnesium
Magnesium is used in approximately 300 roles in the body, including turning food into energy and helping insulin do its job. Low intake is linked with insulin resistance, and it also supports sleep, muscle relaxation and your stress response. You'll find it in leafy greens, legumes, nuts, seeds and whole grains.
Zinc
Zinc is needed to make, store and release insulin, and it helps your cells respond to it. It's also one of the nutrients your thyroid relies on to convert T4 into active T3 (alongside its partner, selenium), and it's essential for a healthy immune system. Oysters, red meat, pumpkin seeds, legumes and eggs are great sources.
** Please note: More isn't better here, though. Long-term high doses can deplete copper and interfere with iron absorption.
Vitamin D
Vitamin D supports muscle function, bone health and insulin pathways. Low levels are common, yes, even in sunny Australia, and are linked with metabolic syndrome. Correcting a deficiency matters, but topping up beyond healthy levels won't shift weight on its own.
Omega-3 fats
Found in oily fish like salmon, sardines and mackerel, omega-3s help calm inflammation, lower triglycerides and support insulin sensitivity and heart health.
Test, don't guess: iron and B vitamins
These two are vital, but they're also where I see the most well-meaning supplement mistakes.
Iron. Heavy or irregular periods in perimenopause can quietly drain your iron stores, leaving you exhausted and puffed on the stairs. But once periods stop, iron needs drop sharply, and too much can do harm. A simple iron studies blood test tells you which camp you're in.
B vitamins. B6, B12 and folate are essential for energy and mood, but they're not a universal pick-me-up. B12 is worth checking if you eat mostly plant-based or take metformin or long-term reflux medication. And high-dose B6 taken over time can actually cause nerve problems.
The bigger picture
No single nutrient is a magic fix, and that's genuinely good news. When protein, key minerals and healthy fats are in place, alongside strength training, good sleep and stress support, your body has what it needs to do its job. That's the real foundation of metabolic health for women over 35.
And if you've been hard on yourself, please hear this: these changes are about physiology, not effort.
Not sure where your gaps are? Take my free Metabolism Detective Quiz to uncover what might be behind your symptoms. [Take the quiz →]
Ready for answers that are specific to you? Book a Health Clarity Call and let's look at the full picture together. [Book your call →]
