Supplements for Mental Health - The Evidence

As you may know, I very recently updated the content on mcmanweb, including my articles on supplements. My position is generally sympathetic, but I also urge skepticism. This extract from a longer article explains why ...

Before we examine the brain, let's look at an adjacent organ - the eye. There are convincing studies, published in reputable journals such as JAMA, showing that various nutrients - in particular lutein (found in dark green leafy vegetables) significantly reduce the risk, or slow the progress, of age-related macular degeneration (AMD).

These studies are not necessarily conclusive, but why they are so convincing is that:

1. They address a condition that everyone clearly understands (loss of vision in the center field).
2. We know this condition's causes and effects (build-up of blood vessels supplying the retina in one form of the illness).
3. We can identify a specific region of the anatomy (the macula in the retina).
4. We know this region's function (high resolution vision).
5. We can identify specific biochemical processes (such as cone cells processing light).
6. We have linked a specific agent (lutein) to the macula.
7. We see a clear link all the way down the chain from treatment (lutein) to structure (intact macula) to function (operating macula) to outcome (good vision, lower risk of AMD). 

Now, let's switch from the eye to the brain, from AMD to depression. Yes, we have studies, but here's what we're up against:

1. They attempt to address a condition that no one understands (feeling sad? loss of energy? irrational thinking?).
2. We don't know this condition's causes and effects (environment? biology?).
3. We can't identify a specific region of the anatomy (hippocampus? amygdala? anterior cingulate? cortices?).
4. Even if we could identify a specific region (in all likelihood we are talking many regions), we are a long way from connecting function to the condition we are trying to fix).
5. Our understanding of the specific biochemical processes is primitive (such as "chemical imbalance" involving serotonin or dopamine).
6. We have not linked any specific agent to any region or any process.
7. We cannot show any clear link all the way down the chain from treatment (with any agent) to structure (such as changes to specific brain regions) to function (such as an optimum anterior cingulate) to outcome (feeling good? more energy? rational thinking?).

Just to be clear, I have used these same arguments elsewhere to demonstrate that we have clear lack of evidence for using antidepressants to treat depression.

Here's where I'm going with this: Pharma has invested billions in clinical trials that have been rigged in every conceivable way to make antidepressants look good, and they have failed miserably. In hindsight, it's easy to see why:

They were testing for the wrong condition ("depression," as opposed to something more specific such as loss of energy or lack of motivation) on a wide population (anyone who was "depressed") with no understanding of the underlying biology or the environmental conditions that bring on "depression".

Thus, if you are skeptical of meds for psychiatric conditions, be equally skeptical of supplements for psychiatric conditions. No matter what you may hear - from any source - we have no credible evidence remotely approaching what lutein does for macular degeneration, nor are we likely to for decades to come.