Depression vs low mood: how your GP tells the difference

I want to start with something reassuring, before any of the rest of it. Feeling low is part of being human. A hard week, a loss, a stretch of stress or poor sleep, a grey season where nothing seems to land, all of that can leave you flat and heavy for a while, and most of the time that is not depression, it is just life pressing on you, and it lifts as things settle. You don't need a diagnosis for every low patch, and you are not weak for having them.

So this isn't about turning ordinary sadness into an illness. It's about the harder question underneath, the one people actually sit with at night, which is "is this just a rough patch, or is it something more?" Let me walk through how I think about that, because there are a few honest signposts, and because the answer matters far less than what we can do about it.

When low mood is just low mood

Ordinary low mood is a bit like the weather. It's real while it's here, it can be genuinely heavy, but it moves. It shifts as you sleep, as the week turns, as whatever set it off starts to ease. And crucially, even in the middle of it you can still be reached, a good chat, a hug, a favourite meal, a decent night's sleep, a bit of sun, and the cloud lifts a little, even if only for a while.

Grief works like this too, and it's worth saying plainly that grief is not depression. Losing someone, or something that mattered, and feeling the floor go out from under you is a normal, healthy human response, not a disorder, even when it's enormous. The same is true of the hard adjustment that comes with a big life change. These things hurt, sometimes terribly, but they tend to come in waves, and they tend, slowly, to soften.

So no, not every low week is depression, and the point of telling the difference isn't to turn ordinary sadness into an illness, it's so that the heavier thing, the one that has stopped moving, gets noticed instead of quietly waited out. And if you do want to come and talk something through, you're always welcome, a rough patch included, you never have to wait until it feels bad enough.

When it's more than the weather

Here's where it shifts. If low mood is the weather, depression is more like the climate settling in, a low that has stopped lifting and started to colour everything, regardless of what any given day brings.

When someone comes in about this, I'm not running a checklist over them, and I'd gently steer you away from doing that to yourself either, because this is something a GP works out with you, in a conversation, not a test you pass or fail on your own. But there are a few things I find myself paying attention to, and they're worth understanding.

The first is that it persists. We often use a rough guide of around two weeks, a low mood, or a loss of interest and pleasure, that's there most of the day, most days, and isn't really lifting. The second is that it spreads. Depression rarely stays politely in the "mood" box. It reaches into sleep, into appetite and energy, into concentration and the ability to make decisions, and very often into the things you used to enjoy, which start to feel flat or pointless even when you go through the motions. That loss of enjoyment has a name, anhedonia, and it's one of the most telling parts, because the systems that normally drive enjoyment and motivation feel like they've gone quiet. And the third is that it gets in the way, of work, of relationships, of the ordinary running of your life, in a way a passing rough patch usually doesn't.

When depression doesn't look like sadness

This is the part people miss most often in themselves. Depression doesn't always look like sadness, and plenty of the time, in the room, it doesn't look like crying at all. It looks like numbness, like feeling nothing much either way, like irritability and a short fuse, like someone who's still turning up to work and still managing the school run and still laughing at the right moments, and quietly wondering why none of it reaches them anymore. If you've been waiting to feel obviously, visibly sad before you'll take this seriously, that wait can keep you stuck a long time. And in teenagers it can look different again, more like irritability or pulling away than visible sadness, which is worth a gentle conversation rather than putting down to moods.

Depression doesn't always look like sadness.

One more thing, and it matters more than the timeline. That "two weeks" is a rough guide, not a rule to wait out. If things ever feel unsafe, if you're having thoughts of not wanting to be here, or of hurting yourself, the clock doesn't apply, please don't wait. Call Lifeline on 13 11 14 or Beyond Blue on 1300 22 4636, any time, and in an emergency call 000. Severity and safety always come first.

What a GP actually does

If any of that has landed and you do come in, the first thing is simply a conversation, an unhurried one, about what's been going on and how long, and how far it's reached into your days. None of it is a test you're being scored on. It's two people working out, together, what's actually happening and what would help.

Part of what a GP does that you can't do from a search bar is check the body, because several physical things can cause or mimic low mood, fatigue and foggy thinking, and they're worth not missing. An underactive thyroid is the classic one, it can look very like depression. Low iron, low B12, low vitamin D, and poor or broken sleep can all drag mood and energy down too. So sometimes a simple blood test, or a few questions about sleep, is part of making sure we're not overlooking something straightforward and treatable.

And if part of what's holding you back is the bigger question, whether any of this is even "bad enough" to bother a GP with, I've written about that more fully in is this worth seeing a GP about your mental health?, and the short version is that uncertainty is reason enough. And because low mood and a racing, restless kind of worry so often travel together, it can help to understand how anxiety shows up in the body too.

The hopeful part: it's common, and it's treatable

Here's what I most want you to take away. Depression is one of the most common things I see, around one in twenty Australian adults goes through it in any given year, going by the latest figures from the Bureau of Statistics, and it is treatable. Most people, with the right support, genuinely do start to feel like themselves again. It isn't a weakness and it isn't a character flaw, any more than a thyroid running slow is a failing. It's a health condition, with real biology and real life circumstances tangled up together, and like other parts of the body, it responds to care.

What "treatable" actually looks like is broader and more in your hands than people expect, and the most powerful parts aren't found at a pharmacy.

• Talking therapy - psychological therapies like cognitive behaviour therapy are front-line, well-evidenced treatment, not a soft add-on, and a GP can help connect you with a psychologist and set up a plan to access that support.
• Sleep - protecting and repairing sleep takes real pressure off mood, and it's often where we start.
• Movement - regular physical activity has genuinely good evidence as part of depression care. Build up gently, and please don't read this as "just go for a run and you'll be fine", it's one lever among several, not a cure you should be able to manage alone.
• Connection - depression pulls you to withdraw, and staying connected to people, even in small ways, is one of the strongest protective things there is.
• Nourishment - eating well, in the sense of giving your body steady, quality fuel and the nutrients it needs, supports energy and mood. This is about being properly nourished, not about cutting anything out.
• Your GP, alongside - the relationship itself is part of the treatment, someone to review how things are going, adjust the plan, and make sure you're not carrying it on your own.

For some people, often when depression is more moderate or severe, medication can be one part of that broader plan too. I won't go into specific medicines here, but the general idea is that they can help settle the brain systems involved in regulating mood. For some people, that can make the rest of the work feel more manageable. It's never the whole answer on its own, it sits alongside everything above rather than replacing it, and it's something you'd weigh up and decide on together with your doctor, never the default, and any change to it is something to plan together rather than do alone.

There's no single right mix. The plan depends on you, and it's worked out collaboratively, and the one thing I'll say with confidence is that reaching out earlier tends to make things easier, not harder.

Where to from here

If you've recognised yourself in the heavier end of this, in the low that has stopped lifting, the numbness, the things that used to reach you and don't anymore, please take it as a reason to start a conversation, not as a verdict you've handed yourself. You don't have to be certain, and you don't have to be at any kind of breaking point, to come and talk it through.

And if it was just a rough patch you saw yourself in, I hope the main thing you take is the reassuring one, that low moods are part of being human, that they usually move, and that you'll know the signposts if one ever settles in and stays.

Whichever it is, you don't have to work it out alone. You can see more of how I approach mental health here, and when you're ready, you're welcome to book an appointment to talk it through.

Written by

Dr David Nguyen

MBBS · FRACGP · GPMHSC Accredited

I'm a GP at Pro Health Care Glenelg with a particular interest in mental health and a holistic, whole person approach to care. I spent time upskilling at a specialist mental health GP clinic in Perth, and I work in this area alongside specialist colleagues.

Learn more about Dr David Nguyen → First published: 2 September 2026 · Last reviewed: 2 September 2026