21. Vitamins and Supplements

Some people choose to take vitamins, herbs, and other natural supplements to help with their physical or mental health, or both. Complementary and Alternative Medicine (CAM) is the blanket term covering these, along with treatments such as acupuncture and massage. Some people rely solely on CAM treatments, avoiding treatments such as pharmaceuticals recommended by medical doctors. Most CAM users, however, combine the two.

While usage varies by country and culture, CAM practices are widespread. One American survey examined people self-identifying as having “anxiety attacks” or “severe depression.”1 Approximately 55% used one or more CAM therapies as part of their treatment. Around 20% of survey respondents saw a CAM provider while about 66% saw a conventional provider (e.g., doctor, psychologist, social worker, or clergy). There was likely some overlap between the two.

A broader American survey reported on CAM usage for all illnesses, not only mental health.2 It identified anxiety and depression as two of the most frequent conditions for which people rely on CAM. These were below only back and neck problems (people seeking mostly chiropractic care and massage treatments).

Can supplements cure mental illness? It depends. As you have learned, mental illness varies greatly between people, and is caused by many factors. Symptoms and severity may differ. Be wary of any treatment promoted as a universal cure for even a single mental illness.

We’ll loosely divide the various supplements into three categories: those that address nutritional deficiencies, those related to neurotransmitters and hormones, and plants and herbs whose extracts are used medicinally.

Nutritional Deficiencies

We’ll start with supplements that address nutritional deficiencies. As you know, many nutrients are needed for the proper functioning of the nervous system. If you aren’t deficient in a nutrient, is taking a supplement helpful? Are there benefits to boosting your level much higher than normal? In general, the answer is a clear no. Your body uses only what it needs. At best, excess intake of supplements will result in very expensive urine. At worst, high levels of some nutrients can be toxic. Furthermore, your body maintains a delicate equilibrium between certain combinations of nutrients. A large excess of one can quickly turn into a deficiency of another.

How much of each nutrient do you need, from food or supplements? National standards for dietary intake provide the most reliable recommendations.3 While you may need more or less for particular health reasons, any large deviations should occur under medical supervision.

Even with an iffy diet, many people only require a well-rounded multivitamin. Additional iron, vitamin B12, vitamin C, and vitamin D supplementation may be needed by some. Be wary of vitamin, mineral, or other micronutrient blends said to benefit mental health. If you decide to use supplements, let your choice be guided by specific deficiencies found in your laboratory testing. Read the labels. Keep in mind the maximum healthy intake of each nutrient. More is not better.

Neurotransmitters and Hormones

The second category of supplements are those related to neurotransmitters or hormones, including their building blocks.

You saw that a shortage of neurotransmitters can lead to mental health symptoms. You need raw materials, known as precursors, to create them. If you don’t have enough raw materials, you won’t have enough neurotransmitters. Supplements are one way to obtain those precursors.

Like vitamins and minerals, precursor supplements address existing deficiencies, but won’t help if you’re not deficient. Other approaches, such as changing your diet, can do the same thing. Taking more than you need won’t help more. Remember, too, that vitamins and minerals, which make up precursors, are used for more than building neurotransmitters. Supplementing only with precursors may neglect these other roles.

Tryptophan and 5-HTP

Tryptophan is an essential amino acid. Your body needs it to function, but can’t make it from other chemicals. It’s widely found in our diet, especially in protein-rich foods. Your body converts tryptophan into a precursor called 5-HTP, which is then converted into serotonin. Tryptophan or 5-HTP supplements may provide a small improvement in depressive symptoms for some. Presumably, these people are deficient. However, such supplements have not been proven to be the safe, side-effect free, and effective natural replacements for serotonergic antidepressants that many had hoped.4

S-adenosylmethionine (SAMe)

SAMe is naturally found in your body. It helps create and destroy neurotransmitters. The liver makes SAMe from vitamins B6, B9 (folic acid), B12, and an essential amino acid called methionine. As B9 and B12 deficiencies are common, a deficiency of SAMe would not be unusual. In those cases, SAMe supplements can improve mild depressive symptoms or boost the effects of antidepressants in those who had a limited response.5 If you have a bipolar disorder, be aware that SAMe can trigger hypomania or mania.

GABA

GABA is the main inhibitory neurotransmitter in your body. Many medications for anxiety increase GABA transport in the nervous system. This slows other signals and improves anxiety and insomnia. Just as it does with other neurotransmitters, your body creates GABA. Like serotonin, GABA can’t reach the brain, so GABA supplements aren’t effective. The medications gabapentin and pregabalin, used for pain, seizures, and anxiety, are almost identical to GABA, but different enough that they can reach the brain.

Omega-3 Fatty Acids

One trendy supplement is Omega-3 (found in fish, flax, etc.). It has been widely investigated for use in unipolar and bipolar depression, ADHD, and aggression and impulsivity in borderline personality disorder.6 The eicosapentaenoic acid (EPA) form of Omega-3 appears to have a greater effect on depressive symptoms than the docosahexaenoic acid (DHA) form. It has a good safety profile and reported benefits in other areas. It seems likely that a deficiency could modestly worsen some mental health symptoms.

Melatonin

This natural hormone regulates body rhythms, synchronizing them with day and night. It’s widely used as a short-term or long-term sleep aid. It also relieves jet lag. Many studies show positive effects, though there are concerns over the quality of the studies themselves.7

L-Theanine

This chemical, found in high amounts in green tea, has long been used for relaxation.8 Good evidence supports this effect. It inhibits the excitatory neurotransmitter glutamate, as well as increasing GABA. Combined with caffeine (as found naturally in tea), it increases attention, improves cognition, and reduces the jitters when compared to intake of caffeine alone. No clear evidence, however, supports its use to treat clinical anxiety disorders.

Inositol

Inositol aids neurotransmitter activity within neurons. It is found in a variety of foods, and the body can create it from glucose. A few small studies suggest inositol supplements may somewhat help depression, bipolar depression, panic, and OCD.9 Inositol is also sold, usually with choline, as a cognition and memory enhancer. Evidence that inositol supplements can affect mental health is limited and primarily anecdotal.

Choline

Choline plays many roles in the body. It’s a building block for the neurotransmitter acetylcholine, which is critical for memory formation and prenatal brain development. The body makes some, but not enough. The best sources are liver, eggs, and peanuts, the food additive lecithin, along with various meat, fish, and dairy sources. Some studies show choline supplements improve cognitive performance.10 Many medications have anticholinergic properties that negatively affect memory and cognition and cause other physical side effects. Choline supplements may help with these problems.

Phenylalanine and Tyrosine

Phenylalanine is an essential amino acid found in many protein-rich foods. It is converted into tyrosine, which is then converted into the neurotransmitters dopamine and norepinephrine. A shortage of phenylalanine or tyrosine decreases dopamine and norepinephrine just as a shortage of tryptophan decreases serotonin. Taking phenylalanine or tyrosine may help with cognition in healthy people under short-term stress. Acute stress causes a rapid turnover of neurotransmitters and therefore potential deficits.11

Herbals

The final category of supplements we’ll cover are plants, herbs, and their extracts. Plants have been used medicinally for thousands of years for mental health. Given the desire of many people to pursue natural treatments instead of manufactured pharmaceuticals, they continue to be used extensively. Or as the introduction to one fairly typical article12 puts it:

Want to relieve your depression symptoms using safe, natural antidepressants? Want an herbal alternative that can improve your depression symptoms without antidepressant side effects?

Do herbals deliver on this promise? Applying modern standards of evidence to herbal treatments has been challenging.13 Only two herbal supplements have been rigorously studied (including reviews and meta-analyses) and found to help in specific situations.

St. John’s Wort

St. John’s wort14 is probably the single most used herbal remedy in mental health. It has been studied extensively and found to be more effective than placebo at treating mild to moderate depression. A few studies found it has a comparable effect to some (older) antidepressants. It has not been shown, however, to help with other mental illnesses, including any form of anxiety.

It has a multitude of effects on several neurotransmitters, most notably serotonin. Unfortunately, it seriously interacts with many herbal and prescription medications, including migraine medications, birth control pills, heart medications, cancer medications, HIV/AIDS medications, pain medications, blood thinners, and most psychotropic medications. In combination with other medications, it can lead to serotonin syndrome (we’ll discuss this in the chapter titled Antidepressants). If you take St. John’s wort, it’s critical to make sure your doctors and pharmacist know.

Kava

St. John’s wort can help with depression but not anxiety. One plant studied extensively for anxiety is kava,15 native to the western Pacific islands. It can modestly improve generalized anxiety disorder when used up to 24 weeks.

Safety concerns regarding liver damage (sometimes fatal) and medication interactions have dogged kava. For years, it was banned outright in some countries, including the UK, Canada, and EU member states. Further investigations have shown that peeled kava root extracted with water (how it was traditionally used) is safe. Virtually all bans have been since replaced by strict regulations on sales and imports. Use caution. Take kava supplements from a regulated source. Be very careful with alcohol or medications that are metabolized by the liver. If you have liver problems, don’t take kava.

Other

Many other herbals are promoted for their mental health benefits. The evidence supporting them is much weaker than for St. John’s wort or kava. We list the main ones in Table 3. The evidence column grades the current state of evidence, as determined by a large review of herbals.16 Even the best (A) have very little evidence compared to St. John’s wort or kava. No herbals have close to the amount of evidence as psychotropic medications or have been shown to help with anything but mild mental illness.

General Cautions

The decision about whether to try a particular natural supplement is not an easy one. Here, we touch on a few factors to consider.

Limited Studies

As we’ve seen, there is a lack of high-quality scientific evidence about the safety and efficacy of many herbal treatments. There are limitations in the size of studies, methodology, measurement, study participants, controls, and many other areas.

Standards

You can grow St. John’s wort in your backyard garden. However, most people using medicinal plants use commercially produced supplements. While prescription medications are closely regulated in most countries, herbal supplements are not as strictly regulated. That puts a much greater onus on you to ensure you’re getting what you think you are.

Natural Medicine is Medicine

Despite being a natural product, natural medicine is still medicine.

It can help your symptoms, have negative effects, cause reactions and illnesses, and even be toxic. It can interact with other medications, natural or pharmaceutical. Those interactions can be potentially dangerous. Many substances, natural or otherwise, affect the liver, where they are metabolized. This can lead to either a toxic build-up or drastic reduction of other medications in your system. Even something as innocuous as grapefruit juice can interact with many medications. Ensure your doctors or pharmacist know everything you take, including herbal products.18

Like other treatments, natural supplements need to work on the problem you’re actually having. Most mental illnesses such as anxiety and depression have a multitude of possible causes. A treatment that works to address one cause (e.g., a deficiency) won’t help if your illness is caused by something else.