The holistic health community talks a lot about “mood-boosting” nutrients. In a few cases, the path to greater positivity may in fact be that simple, other times it is not. We want to talk about the scientific relationships between nutrition and mood. 

Is your mood healthy?

First of all, being happy all the time is not a healthy goal. When life presents us with tragedy and stressful situations, the healthy response is to feel negative about it (worried, sad, or disappointed, etc). These feelings help us recover from a challenge and learn from it, thereby avoiding a repeat experience in the future.

When we are feeling sad or low, it is important to first take a look at life’s circumstances and determine whether or not these are the appropriate feelings. If you have experienced a break-up, a job loss, or a series of less catastrophic challenges, you may need time to grieve or space to heal. This is not a problem nutrition can solve.

If you feel constantly anxious, irritable, or exhausted, could it be that you are stretched too thin with stressful responsibilities? Feeling anxious, irritable, or exhausted are appropriate, healthy responses to too much stress. This is not a problem that nutrition can solve. 

On the other hand, if life’s circumstances are seemingly “going your way”, but you can’t kick feeling blue, tense, worried, or depleted, it may be a good time to examine your nutritional status. There are a few key reasons that your physiology might be causing a low or negative mood when life is presenting opportunities for joy.

Is your diet leaving you blue?

We are what we eat. If we want to be happy and have balanced energy, we have to consume the appropriate building blocks for hormones and neurotransmitters that allow “happiness” feelings, the nutrients that allow us to build cellular energy, and the nutrients involved in metabolizing stress hormones appropriately. 

Many, many nutrients contribute to sustainable mental health, but some of the most important nutrients for mood maintenance are the B-vitamins, vitamin D, omega-3 fatty acids, and magnesium. 

B-vitamins and magnesium are central to the production and metabolism of serotonin (the happiness neurotransmitter) and melatonin (the restful sleep hormone) [1]. B-vitamins and iron are both necessary for efficient cellular energy production by mitochondria [1,2]. 

Vitamin D deficiency has been linked with mood disorders in many clinical studies. The mechanism appears to be related to the dysfunctional regulation of glucocorticoid signaling [3].

Omega-3 fatty acids are important components of cell membranes and hormone structures. They have been shown to have a quelling effect of stress hormones and associated anger and aggression [4].

If you have ruled out situational factors as the cause of your low mood, and you’re sure you eat a healthy, balanced diet, there are still some nutritional rocks left unturned.

Not every body responds the same way to a standard “healthy diet”. Just because we eat nutrient-rich foods doesn’t mean we are all able to absorb or process that nutrition. Some of us have genetic differences that prevent us from processing certain nutrients, some of us have subtle intolerances or autoimmune issues causing our bodies to fight our food. 

Read on to better understand three common roadblocks in the quest for balance in nutrition and mood.

Nutritional Deficiencies Can Be Dietary or Genetic

Diet and Lifestyle

A well-balanced, plant-heavy, whole-food diet that includes modest portions of animal protein and organic grass-fed dairy is, by most accounts, a “healthy” human diet. Many Westerners, specifically, do not eat this way, however. The typical American diet is abundant in calories from fat and animal protein and yet nutritionally deficient in essential vitamins and minerals. 

It has been estimated by different studies that 90% of Americans are deficient in omega-3 fats, 75% are deficient in magnesium, 70% are deficient in calcium, and 30% of children and premenopausal women are deficient in iron [5-8]. Other common deficiencies in the US include folate (vitamin B9), vitamin B12, and vitamin D [9]. 

Yes, you can be overweight or obese and still deeply deficient in essential nutrients.

The other end of the diet spectrum can be nutritionally challenging as well. For example, some people choose to forego the consumption of animal products. While this may be a noble choice environmentally and/or ethically, it does require making educated decisions about sources of iron, B-vitamins, calcium, essential amino acids, and more, when these nutrients are found most readily in flesh and dairy. A plant-based diet can quickly leave someone deficient in these nutrients.

Vitamin D is tricky too. Vitamin D is not technically essential, as your body can make it internally, just by spending time exposed to the sun. The problem is, this nifty evolutionary trick of the human body does not account for a 40-hour(+) workweek or our migration into places where exposure of skin to sunlight is near impossible. 

If you live somewhere cold or somewhere dark, you always wear sunscreen, or you generally spend daylight hours indoors, you are likely to be vitamin D deficient. For many, the simplest solution is a vitamin D supplement.

Genetic Deficiency

An example of a highly common deficiency caused not by diet, but by genetics, is folate (vitamin B9). There are genetic variations in a gene known as MTHFR, that code for less efficiency in the enzyme that transforms dietary folic acid into its usable form, L-methylfolate

These genetic variations are so common, it has been estimated that more than half of the global population has inherited one or more copies of the faulty gene [10]. The consequences of inheriting these faulty genes are that unprocessed folic acid can build up when the MTHFR enzyme is not working properly, and your body can be functionally folate-deficient, even when taking folic acid supplements. 

A solution to this problem is L-methylfolate supplements. Supplementing with L-methylfolate directly bypasses the need for the MTHFR enzyme. L-Methylfolate can be absorbed, circulated, and used immediately by the body. This is important for mood as L-methylfolate is a mediator of serotonin synthesis and signaling [10].

In other words, for some deficiencies, there is no way of knowing by examining the diet. You need a blood test to determine both your genotype and your circulating methylfolate levels. Luckily these tests are rather simple and can be conducted by your practitioner.

 Is your low mood a “gut feeling”?

When we are scared or stressed, putting us in “fight or flight” mode physiologically, our digestion shuts down to maximize available energy for fighting or fleeing. 

But the brain-gut connection goes the other direction too and can be a lot more nuanced. 

We rely on certain microbial species for proper digestion. When these beneficial species are present and diverse, they break down food that our human digestive system cannot, allowing us to absorb much more nutrition from what we eat. Regularly consuming probiotics bolsters the microbiome living in our gut, and ensures the most beneficial species are populating the space. 

Probiotics improve the bioavailability of all B vitamins as well as many essential minerals such as calcium, zinc, iron, phosphorus, copper, and magnesium [11,12].

The opposite of a probiotic community living in your gut is a dysbiotic microbiome. A poor human diet (low fiber, high sugar) can starve probiotic species and allow the growth of harmful gut bacteria and yeast. The result, dysbiosis, is not only physically uncomfortable (with symptoms like gas, bloating, diarrhea, or constipation) it can also have an effect on your mental health.

Dysbiosis in the gut microbiome has been correlated with several neuropsychiatric disorders, including Parkinson’s disease, autism, schizophrenia, and depression [13]. Outside of those clinical diagnoses, healthier gut microbiomes have been linked to faster physical recovery from stress, better emotional health during postpartum periods for mothers, and couples with healthier guts have healthier marital discourse [13]. 

None of this is proof that taking a probiotic will treat or prevent disease or unhappiness in your life. It is simply evidence of an important gut-brain connection. And, the mechanisms by which healthier gut populations elicit these effects are still under investigation. The data clearly indicate, however, that a healthy gut supports a healthier brain.

Is your low mood “all in your head”?

Speaking of brains, markers of inflammation in the brain have also been linked to mental health.

Mental health is historically a difficult area of medicine to study, as symptoms all must be self-reported, rather than observed or measured quantitatively by researchers. It has been discovered, however, that measurable, observable inflammation in the brain is common across many mental health conditions [14]. 

While some inflammation is a healthy part of immune reactions, chronically high inflammation has negative impacts on central nervous system function, including neurotransmitter metabolism, neuroendocrine function, synaptic plasticity, and regional brain activity [14]. All of these impacts can affect your mood and mental health.

Again, if this is happening in your body, that is something a professional would have to assess. It is just important to know that it is a possibility when we are struggling with mood. 

We can, however, be sure to act and eat accordingly to reduce or balance inflammation in the body and brain. Filling your diet with antioxidant foods (typically intensely pigmented foods like berries, peppers, etc.) and adding immune-supportive supplements to your daily regimen can be helpful. 

Specifically, look for vitamins A and E, B-complex vitamins, vitamins C and K, and omega-3 fatty acids. Add a vitamin D supplement if you are not spending time with bare skin exposed to the sun every day.

Be wary about your omega-6 fats (hydrogenated oils), caffeine, sugar, and alcohol intake. All of those can promote inflammation. Look at your sleep and exercise patterns, and assess whether you are getting enough (or too much) of each.

Look up “anti-inflammatory diet” for more exhaustive anti-inflammatory food suggestions, shopping lists, and “do’s and don’ts” to reduce inflammation. 


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