Supplements

The honest version

Most of what is written about supplements and mental health is written by people selling supplements. This page is not that. It is an account of where the evidence is reasonable, where it is thin, and where a supplement can actively interfere with psychiatric treatment.

The short version: supplements are not a substitute for treatment of a depressive episode, an anxiety disorder, bipolar disorder or OCD. Where they genuinely help is in correcting a deficiency that is contributing to how you feel, and occasionally as an addition to treatment that is already working. Those are real but narrow roles, and they are worth doing properly.

Test before you treat

This is the part that gets skipped. Correcting a deficiency and supplementing someone who is already replete are different things with different results — the first can change how a person feels substantially, the second usually does nothing.

Several ordinary deficiencies produce symptoms that look convincingly like depression or anxiety: low thyroid function, iron deficiency with or without anaemia, vitamin B12 deficiency, and vitamin D deficiency. Fatigue, poor concentration, low mood and reduced tolerance for exertion are common to all of them.

Because this practice is led by a clinician trained in both psychiatry and primary care, we order and interpret laboratory work directly rather than referring it back out. If something measurable is contributing, we would rather find it than supplement around it.

Where the evidence is reasonable

Correcting a documented deficiency. Iron, vitamin B12, folate and vitamin D, where testing shows a genuine deficiency. This is the strongest and least controversial use, and it is a medical intervention rather than a wellness one.

Omega-3 fatty acids. Studied as an addition to antidepressant treatment for depression, with mixed but not negligible results. The composition of the preparation appears to matter, and the effect is modest.

Melatonin, understood correctly. Melatonin is a circadian timing signal, not a sedative. It has a legitimate role in shifting a sleep schedule — jet lag, delayed sleep phase, shift work. People who take it expecting a sleeping tablet are usually disappointed, and for chronic insomnia the first-line treatment is cognitive behavioral therapy for insomnia, not a supplement.

Where the evidence is thin

Magnesium for sleep and anxiety, amino acid derivatives marketed for calm or focus, and most adaptogenic herbs fall here. Some have small or short trials behind them; few have the kind of replicated evidence that would justify using them in place of treatment. That does not make them useless. It means the honest description is “possibly helpful, not established,” and anyone telling you otherwise is overselling.

Interactions — the part that gets missed

This is the section we most want you to read, because “natural” is not the same as “inert,” and supplements are regulated as foods rather than as medicines. Purity and dose can vary between brands and between batches of the same brand.

• St John’s Wort is the most important one. It induces liver enzymes that clear a wide range of medications, which can reduce the effectiveness of hormonal contraception, certain heart and transplant medications, and some antiretrovirals. Combined with serotonergic antidepressants it also raises the risk of serotonin toxicity. It should not be started alongside psychiatric medication without a clinician involved.
• Anything serotonergic — including certain amino acid precursors sold for mood — carries the same serotonin toxicity concern when combined with antidepressants.
• Some herbal preparations have been associated with liver injury. Reports exist for several popular products, and they are worth knowing about before starting one.
• Stimulating supplements, including high-dose caffeine and the “energy” and “focus” category generally, can worsen anxiety, disrupt sleep and complicate ADHD treatment.
• Pregnancy, breastfeeding and surgery each change the calculation, and several supplements should be stopped before an operation.

Tell whoever prescribes for you everything you take, including things bought without a prescription. Not because anyone will disapprove — because interactions are the one part of this that can cause real harm.

How this works in our practice

Supplements are considered as part of integrative psychiatric care alongside diagnosis, medication where appropriate, therapy, sleep and laboratory findings. They are not the centre of a treatment plan, and we will say so plainly if what you need is a psychiatric evaluation rather than a supplement.