Dr Libby: Tired all the time? The overlooked energy drains you can actually fix

With the first month of the year behind us, it’s time for an energy check-in.

As routines re-emerge as we get into the swing of the year, many notice a lingering tiredness that doesn’t quite lift with sleep, sunshine or a return to normal nourishment. Energy feels thin. Motivation is harder to summon.

You might tell yourself it’s just the hangover of a busy end to last year or the shock of returning to work. Sometimes that’s true. But sometimes it’s biochemical. Energy is not a single switch you turn on with more coffee or earlier nights. It is the result of many systems working well together. When even one of those systems is under strain, energy becomes something you push for rather than something that carries you.

One of the most common and overlooked contributors to low energy is iron. Iron helps transport oxygen to your cells, supports energy and thyroid hormone production and underpins cognitive clarity and mood. When iron is low, everything requires more effort. Yet iron deficiency rarely arrives with flashing lights. It often whispers first. Persistent fatigue, feeling flat or unmotivated, breathlessness (especially on exertion), hair shedding, cold hands and feet, changes in concentration, brain fog and increased anxiety are all common signs of inadequate iron. If you’re starting the year with flagging energy, testing your iron levels is a great place to start.

The “normal” range for ferritin (your iron storage tank) on blood tests is quite broad, ranging from 20 - 200 µg/L [micrograms per litre]. In my professional opinion, the lowest end of the range is too low and clinically, I would find that anyone with ferritin below 50 µg/L would be experiencing the symptoms of low iron. I believe most people feel their best with levels closer to 80-100 µg/L.

This isn’t about chasing numbers for the sake of it. It’s about understanding what your body needs to feel resilient, energetic and emotionally steady. Iron status is not static. Menstrual blood loss, pregnancy, childbirth, breastfeeding, endurance exercise, stress, gut health and dietary patterns all influence iron levels over time.

Of course, energy issues are not always related to iron – or perhaps not just iron. Sometimes we’re simply not getting enough of the raw materials the body requires to create energy in the first place.

Energy is made from food, but only when that food is accompanied by the nutrients that allow it to be converted into usable fuel. Inadequate protein or B vitamins, insufficient magnesium and zinc, or inconsistent eating patterns can all undermine energy production. Focus on eating whole, real food – good-quality protein, nourishing fats and plenty of vegetables – and reducing takeaways, ultra-processed foods and deep-fried foods – to ensure you’re getting as much nourishment from your food. Good-quality food-sourced supplementation can help to fill in any gaps.

Muscle mass is another often-overlooked contributor to how energised we feel. Muscle tissue contains a high concentration of mitochondria, the tiny structures within cells responsible for producing energy. As muscle mass declines, which can occur with age, inactivity or chronic stress, so too does the body’s capacity to generate energy efficiently. This is not about aesthetics or intensity, but about function. Regular, appropriately challenging movement, particularly resistance-based exercise, supports mitochondrial health and helps energy feel more robust and sustainable over time.

Stress, of course, can have a profound impact on energy, even when it feels familiar or manageable. When the body perceives ongoing demand without adequate recovery, stress hormones remain elevated. While these hormones can keep you going in the short term, they do so at a cost. Over time, energy becomes borrowed rather than generated. Sleep quality suffers, blood sugar regulation becomes less stable and the nervous system remains on high alert. The result is often a tired-but-wired state that no amount of rest alone seems to resolve.

Thyroid function is another important piece of the energy puzzle. Thyroid hormones help regulate metabolic function and a lack can present as fatigue, brain fog, feeling cold, low mood or difficulty maintaining energy across the day. Thyroid health is closely linked to nutrient status, particularly iron, iodine, selenium and zinc, as well as stress and immune function. When fatigue feels bone deep, it can be helpful to consider whether the thyroid is being adequately supported.

Finally, I believe energy is not purely biochemical. There is a particular kind of fatigue that arises when we are living out of alignment with our values, priorities or sense of self. This type of tiredness often persists even when nutrition, sleep and movement are addressed. It is the exhaustion of continually overriding what feels true or meaningful. While food and nutrients lay the foundation for energy, how we live upon that foundation also matters. When actions, boundaries and choices better reflect what truly matters to us, many people notice a subtle but powerful lift in energy that no supplement alone could provide. So if all else fails, consider whether you would benefit from making changes to how you’re living. Are you creating enough space for the things that light you up or are you all routine and work/family commitments? Ask yourself, “How do I want to live?” and make small – and large – adjustments to get closer to that.

Dr Libby Weaver PhD is a nutritional biochemist, 13 times best-selling author and international keynote speaker. For more on balancing your hormones, visit Drlibby.com

More from Dr Libby

The morning habits that make you healthier (including the best time to have a coffee). Try these simple science-backed tips for better energy all day.

Simple Ways To Calm An Overstimulated Nervous System. Overstimulated after Christmas? A nature-based reset could soothe your nervous system.

What I Buy In My Weekly Grocery Shopping List. ‘Whenever I’m doing my food shop I’m reminded that it’s the small, consistent choices that end up having the greatest impact on our health.’

How Reducing Screen Time Can Transform Your Wellbeing - And How To Do It. What impact do our devices have on our health?