TOP 5 nutrients for a good mood

There are three main options for how food can improve your mood:

1. Delicious food can instantly make you happier. But this is often temporary.
2. A balanced diet helps keep you fit and healthy. A healthy body is better for your mood than an unhealthy one.
3. Certain nutrients found in foods can improve your mood.

In this article, we look at five nutrients that affect mood: 

Magnesium, zinc, vitamin D, omega-3 fatty acids, and tryptophan.

Magnesium

Magnesium has many bodily functions, so the potential mechanisms for its effect on our mood are numerous.

* Magnesium is an essential mineral needed for energy production, carbohydrate metabolism, and DNA and protein synthesis.—Editor’s note.

Like zinc and vitamin D, magnesium can influence mood hormones. Low magnesium levels are associated with low testosterone, and low testosterone is associated with a worse mood in men and women.

Magnesium can also directly affect the brain. According to preliminary data, magnesium modulates the activity of NMDA receptors (a type of glutamate receptor located on neurons). This explains why low levels of this mineral can cause abnormal firing of neurons, leading to anxiety.

Observational studies show that people with anxiety disorders tend to have lower magnesium levels. And a systematic review of 18 studies suggests magnesium supplements may help people prone to anxiety. 

However, the existing studies on the association of magnesium with anxiety are of rather low quality. In a more recent triple-blind, randomized control trial,  magnesium supplementation failed to alleviate postpartum anxiety and depression in women. A 2018 systematic review and meta-analysis found insufficient evidence that magnesium can alleviate symptoms of depression. Magnesium supplementation has only been associated with reducing depressive symptoms in uncontrolled studies.

Magnesium deficiency is quite common, especially in the elderly. In addition, since magnesium (like zinc) is excreted through sweat, athletes should be especially careful about their intake. 

Athletes in sports requiring weight control are particularly susceptible to magnesium deficiency.

You can easily reach your recommended daily allowance:  magnesium-rich foods are plentiful and suitable for all kinds of diets. And while high doses of supplemental magnesium can cause  diarrhea  and other gastrointestinal problems, “magnesium taken naturally through food has no adverse effect.”

If you do feel the need to supplement,  avoid magnesium oxide: it has low bioavailability ( rats only absorbed 15% in one study, only 4% in another  ) and is more likely to cause intestinal discomfort and diarrhea.

RDA for magnesium

Women who are pregnant or lactating

* Adequate Intake (AI)

Mixed evidence from observational studies link low magnesium to anxiety but not depression. Accordingly, mixed evidence from intervention studies suggests magnesium supplements are more likely to help anxiety than depression. As a practical matter, if you’re eating enough magnesium-rich foods, a magnesium supplement probably won’t improve your mood.

Zinc

Like magnesium,  zinc is an important mineral with many functions. First of all, as a catalytic and structural element in hundreds of metalloproteins (editor’s note).

A cross-sectional study of data collected from 14,834 Americans (7,435 women and 7,399 men) between 2009 and 2014 found an association between depression and zinc deficiency. Similarly, a cross-sectional study of data collected from 2,019 pregnant women between 2002 and 2005 found that being in the high zinc intake quintile* appears to attenuate the effects of stress and hence the development of depressive symptoms.

* quintile, from English. A quintile is a statistical value of a data set used to create thresholds for a given population. – Editor’s note.

However,  cross-sectional studies are like snapshots: they can show correlation but cannot establish causality. Zinc deficiency has been linked to depression, but did it cause depression? Or did depression cause a zinc deficiency? Or maybe depression and zinc deficiency were caused by some other undetermined factor?

These studies cannot answer these questions. Fortunately, some randomized trials in which people participate for a long time show that zinc supplementation increases the effectiveness of antidepressant treatment. Research one,  two, and three.

And in this case, we still do not know all the operating mechanisms. We know that zinc affects the immune system and brain homeostasis, and like magnesium, it can act on NMDA receptors in the brain. Also, as with magnesium and vitamin D, low zinc levels can interfere with testosterone production, and low testosterone levels are associated with low mood in both men and women.

However, if you are not deficient in zinc, simply taking more zinc is unlikely to help. This may be why, in a recent triple-blind RCT, zinc supplementation failed to alleviate postpartum anxiety and depression. It is worth noting that the factors that lead to postpartum anxiety and depression can be very different from those that lead to clinical anxiety and depression in other cases.

Excess zinc is also not a good story. Exceeding the recommended daily allowance can be harmful: in the short term, it can cause nausea and vomiting; in the long run, it can lead to copper deficiency.

RDA for zinc

Women who are pregnant or lactating

* Adequate Intake (AI)

However, while overt zinc deficiency is rare, it can still occur. It has been documented in people suffering from malabsorption syndromes –  including  Crohn’s disease, celiac disease, and short bowel syndrome. In addition, even healthy people can be deficient in zinc—especially the elderly. Finally, since zinc, like magnesium, is eliminated through sweat,  athletes should be especially careful about their intake.

Fortunately,  zinc-rich foods are not uncommon. Zinc is found primarily in animal products, but with some planning, vegans can reach their zinc intake without supplementing.

Vitamin D

Overall, depression has been associated with vitamin D deficiency (≤20 ng/mL), and vitamin D deficiency is estimated to affect about half of the world’s population.

However, just because depression is associated with vitamin D deficiency does not mean that vitamin D deficiency is the main or only cause of depression. During the winter months, when there is less sun, you can suffer from the seasonal affective disorder, which is associated with reduced vitamin D production (due to low exposure to solar UV rays) and shorter daylight hours. 

Five reviews examined the effect of vitamin D supplementation on mood. A 2015 review found no significant reduction in depression. However, the authors did not rule out that vitamin D supplementation may be more effective for people with more severe depression or lower vitamin D levels than most studies. Four other reviews published in 2014, 2016, 2017, and 2018 benefitted from supplementation. Still, three cited poor methodological quality ( one,  two,  three ), and two cited the risk of publication bias ( one,  two ).

The recommended daily allowance for vitamin D is 400 to 800 IU (International Units IU).

These amounts, which some researchers criticize as insufficient, can only be obtained naturally from a  few food sources – in particular, oily fish (salmon, tuna, and sardines). 

Because few foods are rich in vitamin D, supplements are a viable option. If a blood test shows low vitamin D levels, supplement at 2,000 IU (IU) per day and then test again in a couple of months.

Omega 3 fatty acids

Three large systematic reviews of observational studies and RCTs concluded that fish oil might improve clinical depression, especially when used in addition to standard antidepressant therapy ( one,  two,  three ).

However, some researchers stress that the evidence remains weak because different studies used different designs and methodologies, including combinations and doses of omega-3 fatty acids.

Essential fatty acids (EFAs) are polyunsaturated fatty acids (PUFAs) that your body needs but cannot produce. 

There are only two types of EFAs: linoleic acid (LA) and alpha-linolenic acid (ALA). Neither is active, so the body converts the former primarily to arachidonic acid (AA) and the latter to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). LA and AA are omega-6 fatty acids, while ALA, EPA, and DHA are omega-3 fatty acids. EPA and DHA make up the majority of PUFAs in fish oils.

Several mechanisms of action have been proposed to explain the effects of PUFAs on depression, omega-3 fatty acids, EPA, and DHA, but on a practical level, what stands out is that EPA appears to reduce depression more than DHA.

EPA and DHA are found mainly in seafood. In particular, in oily fish (salmon, tuna, and sardines). Most plant foods contain omega-3 fatty acids in the form of ALA, a small amount of which the body converts to EPA and DHA. For vegetarians and vegans, the only rich source of EPA and DHA is algae oil in supplement form.

Preliminary evidence suggests that EPA and DHA, two omega-3 fatty acids abundant in fish oils, may help relieve clinical depression, especially when added to standard antidepressant therapy.

Tryptophan

Tryptophan is an essential amino acid. This means that it is needed by the body but cannot be synthesized and must be supplied with food. Your body needs at least 4 mg of tryptophan per kilogram of body weight per day (4 mg/kg/day).

Your body uses tryptophan primarily to produce serotonin, a neurotransmitter that helps regulate mood. 

Research has shown that healthy people who get enough tryptophan experience less anxiety, irritability, and depression.

According to some researchers, the total amount of tryptophan consumed is less important than the ratio of tryptophan to other amino acids  ( one,  two ). If they are right (although there is currently little evidence to support their hypothesis), simply eating a high-protein diet will not give you all the mood benefits. You will have to give preference to foods rich in tryptophan.