Do nutritional supplements help with mental health? Part 1: Vitamins that don’t begin with a ‘B’.
I’ve been looking into nutritional treatments for bipolar disorder recently. I was taking a multi-vitamin up until a while ago (ironically enough I stopped taking it because I got depressed and couldn’t be bothered). There’s products available like EmPowerPlus that look a lot like really expensive multi-vitamins to me (with some other stuff thrown in, admittedly). So I decided to take a stroll through pubmed and see what kind of evidence there are for various vitamins, minerals and other ‘nutritional supplements’.
First some notes.
My only qualification for doing this is that I’m reasonably scientifically literate and I find this kind of stuff fairly interesting. Anyone with access to the internet could do the same thing. I generally haven’t seen anything more than the abstracts of the papers I’ve linked to (I don’t have access to a university library and I’m not going to pay for them). To be honest, I probably wouldn’t be able to evaluate their reliability or the effectiveness of their methods even if I did read the whole things.
I’m specifically looking at the role of these substances in (some) mental illness – vitamins and minerals may be wonderful for other things. I don’t know – I haven’t looked. Also, I’ve focused on depression, bipolar disorder and schizophrenia.
This is part one, in which we look at all the vitamins that aren’t one of the B vitamins. Part two, which I’ll hopefully post tomorrow, will be for the eight B vitamins. Parts three and four will be for minerals and other stuff, respectively.
Anyway, without further waffling:
Vitamin A (Retinol)
One schizophrenia researcher has written a couple of papers that suggest that retinoids (which are chemicals the body makes from Vitamin A) may be implicated in schizophrenia. I wasn’t able to find anything to suggest that Vitamin A supplementation could help with any mental illnesses. Vitamin A deficiency isn’t really a problem in developed nations anyway.
Recently a big meta-study in the UK looked at a number of different supplements. Vitamin A supplementation (as well as beta-carotene supplementation, which is essentially the same thing) appears to increase mortality. There’s an increased risk of lung-cancer, particularly for smokers.
So, to sum up, there’s no clear benefit to taking additional vitamin A, deficiency in developed nations is rare and vitamin A supplements may have harmful effects.
Vitamin C (Ascorbic Acid)
There’s some research from the 1980’s that showed raised levels of the element vanadium in people who have manic depression. Some of this work speculated (not very convincingly) that these high levels of vanadium cause manic depression. Vitamin C increases the rate at which vanadium is excreted via the kidneys. There was at least one study that compared vitamin C to the then standard drug used in treating manic depression:
There was no significant difference between the response of depressed patients to amitriptyline or ascorbic acid and EDTA. Manic patients responded significantly better to lithium than to ascorbic acid and EDTA. These results are in keeping with the suggestion that vanadium may be of aetiological importance in depressive psychosis, but do not support such a suggestion for mania.
Recently, vanadium has started to be sold as a supplement and has been (so far fairly inconclusively) investigated as a treatment for type II diabetes. Neither the people in these studies, nor those taking it in the form of commercially available supplements appear to report depression or mania as a side-effect. In other words, the evidence is very limited and the limited evidence that there is seems contradictory.
Vitamin D (ergocalciferol, cholecalciferol, etc.)
Over the last ten years, there’s been a growing amount of work linking vitamin D to schizophrenia. It looks like your mother not getting enough vitamin D while she was pregnant could increase your risk of developing schizophrenia.
The connection seems to have initially been made in 1999 by McGrath:
The central nervous system is increasingly being recognised as a target organ for vitamin D via its wide-ranging steroid hormonal effects and via the induction of various proteins such as nerve growth factor. This paper proposes that low maternal vitamin D may impact adversely on the developing foetal brain, leaving the affected offspring at increased risk of adult-onset schizophrenia. The hypothesis can parsimoniously explain diverse epidemiological features of schizophrenia, such as the excess of winter births, increased rates of schizophrenia in dark-skinned migrants to cold climates, the increased rate of schizophrenia births in urban versus rural setting, and the association between prenatal famine and schizophrenia.
This small study looked at a family with a high prevalence of psychiatric disorders and a hereditary defect in the vitamin D receptor gene. It only involved 40 people, 18 of whom had relevant psychiatric disorders and conluded that there was no link between vitamin D and psychotic illness.
However, a much larger study from Finland (a cohort study of just over 9000 people) found that “Vitamin D supplementation during the first year of life is associated with a reduced risk of schizophrenia in males. Preventing hypovitaminosis D during early life may reduce the incidence of schizophrenia.” Recent studies using rats and mice are also quite persausive.
So although I didn’t find any studies that showed taking vitamin D could help with your own mental illness, if you’re pregnant getting enough vitamin D could reduce your child’s risk of developing schizophrenia. This is likely to be more important if you live somewhere it’s not very sunny and have dark skin.
Vitamin E (tocopherols and tocotrienols)
Like vitamins A and C, vitamin E is an antioxidant. There’s a theory that schizophrenia may be caused by oxidative stress, which vitamin E may protect from. There’s been a couple of recent studies using vitamin E in combination with vitamin C and Omega-3 fatty acids as an adjunct to anti-psychotics. While both reported positive results, they were both small studies with only 50 subjects combined and neither provided a control group. As the first of these said: “Future studies need be done in placebo-controlled trials and also with a comparison group supplemented with fatty acids alone in a larger number of patients, both chronic as well as never medicated, and for a longer duration of treatment while the dietary intake is monitored.”
There’s also been research into whether vitamin E (possibly combined with vitamin C) can protect against tardive dyskinesia and neuroleptic-induced parkinsonism. While some of these individual studies have reported positive results, a Cochrane review of Vitamin E for neuroleptic-induced tardive dyskinesia found that “Small trials with uncertain quality of randomisation indicate that vitamin E protects against deterioration of TD but there is no evidence that vitamin E improves symptoms of TD.”
Another study linked low plama levels of vitamin E to major depression, but concluded that ” plasma levels of alpha-tocopherol are lower in depression, but this is not likely to be the result of inability to meet recommended dietary intake.” This doesn’t contribute to a case for taking supplemental vitamin E.
On balance, the current evidence is that if you’re taking an anti-psychotic, vitamin E supplementation might help stop you developing tardive dyskinesia or keep your tardive dyskinesia from getting worse. It won’t make it get better, though. Remember though, there’s also evidence that taking vitamin E and C supplements can increase mortality.
Vitamin K (phylloquinone, menaquinone, etc.)
Vitamin K is a group of chemicals that are mostly used in blood coagulation. There doesn’t seem to be any research into any possible connection with mental illnesses, although this case report from earlier this year seems interesting:
We report the case of a 26-year-old woman suffering from borderline personality disorder (BPD), major depression and bulimia nervosa according to DSM-IV who showed unexplained impairment of the vitamin K-dependent coagulation pathway. Subsequently we discuss different manifestations of self damaging behaviour and comorbidities, as well as psychosocial issues potentially leading to coagulation abnormalities or complications in patients with BPD.
There appears to be very little evidence that taking any of these vitamins will improve your mental health, although there’s at least some evidence that if your mother got enough vitamin D while she was pregant, you’ll be at a slightly reduced risk of contracting schizophrenia. If you’re taking neuroleptics and have tardive dyskinesia, there’s some limited evidence to suggest that vitamin E may stop it symptoms from getting any worse, but that’s something you should probably speak to your doctor about. In general, I don’t see any reason for most people to take supplements of any of these for mental health purposes.