Before You Treat Your Mind, Test Your Body

How many people get diagnosed with a mental health condition when in reality they are living with an undiagnosed physical one? How many people get prescribed antidepressants when the actual problem is happening in their body?

I think that in the future we will look back at this phase of mental health care in a similar way to how we now look at lobotomy. Surely I can say that we're doing our best, but it doesn't change the fact that the gap between physical and mental health care is huge.

A person suffering from depression or anxiety gets prescribed medication almost instantly. No extended testing of the endocrine system, no look at metabolic health - which are two major influences on our mental state.

There's a name for this

Diagnostic overshadowing is what happens when someone already carries a psychiatric label and their physical symptoms get filed under that label rather than investigated. A systematic review published in eClinicalMedicine in January 2025 pulled together 79 studies spanning two decades of research and found that having a mental health condition is associated with a significantly increased risk of a physical health problem going undiagnosed or being diagnosed late. The authors are careful to say that most of those studies measured outcomes rather than causes, so we can't yet separate how much of this comes from clinicians and how much from patients. But the direction is not in doubt. In one study, clinicians attributed cancer symptoms to a patient's underlying disability in half of all cases. In a British emergency department study, where a diagnosis was missed, a psychiatric diagnosis was implicated 77% of the time. Give me a break!

And we have known this for a long time. Back in 1979, Koranyi screened over 2,000 psychiatric clinic patients and found that in 46% of cases a physical illness had been missed entirely by whoever referred them. Psychiatrists overlooked around half of the major medical illnesses in the patients they themselves referred. Diabetes was one of the most commonly missed. Forty-five years, and the reviews are still finding the same pattern.

What a blood panel would show

Another example is overt hypothyroidism, which carries depressive symptoms in roughly half of cases.

And one - in a meta-analysis of 37 studies covering more than 13,000 depressed patients, the researchers found that about a quarter showed low-grade systemic inflammation, and over half had mildly elevated CRP. That is a physical marker, measurable in a standard blood panel, present in a large chunk of people who are being treated purely as a mind problem.

We already know this

The thing is, people already know this. We all know, whether intuitively or consciously, that what we do with our bodies has a direct effect on our mental health. An inflammatory diet loaded with sugar, additives, preservatives and God knows what else, will cause fatigue and brain fog, which can be easily mistaken for depression. Eating foods you are sensitive or allergic to will increase the stress you experience, which might seem like having a panic attack or anxiety. Poor sleep will lead to low energy, easily mistaken for "laziness" or lack of motivation. Lack of movement can look identical to depression from the outside. I could keep going with simple examples like that.

And I'm not even going to start on alcohol, caffeine and cigarettes. Boy oh boy, how many people would rather take antidepressants than cut out these substances first, when all three can completely derail cortisol levels, microbiome health and mood stability.

The feedback loop runs both ways

The same rule applies to positive habits. Eating less processed food will lift mood and energy levels. Making sure you take enough time to move during the day will keep your energy flowing, which increases motivation and creativity.

It's a feedback loop where positive physical habits will positively influence our mental health, and our positive mental attitude and state will lead to better physical outcomes. A lot of research in the past focused on the latter - how the positive attitude can lead to better physical health - but what doesn't get much attention is how our physical health can support our mental health.

And these aren't soft effects. The SMILES trial in 2017 took adults with moderate to severe major depression and gave one group dietary support and the other group social support, for twelve weeks. Around a third of the diet group hit remission, compared with 8% of the control group. That is a large effect for an intervention with no side effects other than better health. On the movement side, a 2024 network meta-analysis in the BMJ pooled 218 studies and over 14,000 participants, and found walking, jogging, yoga and strength training all produced meaningful reductions in depression, with the effects larger the more vigorous the activity. The authors argued these should be treated as core treatments for depression, sitting alongside therapy and medication rather than beneath them.

It gets worse before it gets better

The thing with positive habits like this, however, is that when you first start them you will experience resistance and, possibly, a worsening of symptoms (especially if you're changing your diet). There is now solid evidence that the gut microbiome influences mood, motivation and emotional regulation. When you cut out the food that has been feeding the less helpful species, processed food and high sugar in particular, the composition of your gut starts to shift, and that shift is not comfortable. Fermentation patterns change, gas production changes, and for a week or two you can feel considerably worse before you feel better. Add sugar and caffeine withdrawal on top, both of which are real and well documented, and the first couple of weeks can feel like evidence that the change isn't working. That's why it's so important to keep your focus on your goals.

Similarly, when you start moving after months or even years of inactivity, you are asking your body to handle a load it hasn't handled in a long time. You get delayed onset muscle soreness, a temporary inflammatory response, disrupted sleep and a general sense of feeling rough. That is your body adapting, and it will settle once you get used to these changes.

It is crucial to pass through these initial stages, and important to remember that things will get better and that our mental health, and our overall health, will improve. FYI that's why so many people quit diets or new exercise regimes within the first month - it gets worse before it gets better.

What the timeline actually looks like

From my personal experience, you can start seeing positive results after 2 to 3 weeks. At first, the effects will be very temporary and fleeting, but will become more stable after 3 months. The first week is the worst when you're changing your physical habits or stopping an addiction.

Where to start

My final summary point is this. Before you address your mental health, take a look at your physical health first. Do all the tests you can, start eating clean, and ensure daily movement. Even if there is a parallel mental health issue, it will be 10x easier to address it while you're working on your physical health too.

The first step is to make a decision on one thing you want to change (such as cutting out one specific food or start exercising), and start right now. Not tomorrow, not next week, not after holidays. What is the one thing you can change right now?

One thing I want to be clear about: none of this is an argument for stopping medication you're already on, and that's not a decision to make alone. It's an argument for what should happen before the prescription pad comes out, and for what should keep happening alongside it.

References

Liberati, E. et al. (2025). Diagnostic inequalities relating to physical healthcare among people with mental health conditions: a systematic review. eClinicalMedicine, 103026.

Koranyi, E.K. (1979). Morbidity and rate of undiagnosed physical illnesses in a psychiatric clinic population. Archives of General Psychiatry, 36, 414-419.

Osimo, E.F. et al. (2019). Prevalence of low-grade inflammation in depression: a systematic review and meta-analysis of CRP levels. Psychological Medicine, 49, 1958-1970.

Jacka, F.N. et al. (2017). A randomised controlled trial of dietary improvement for adults with major depression (the 'SMILES' trial). BMC Medicine, 15, 23.

Noetel, M. et al. (2024). Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials. BMJ, 384, e075847.