Food For Good Mood

You are what you eat!  This phrase has dominated the media for decades and it’s true (well, if we were to get technical, you are what you digest and utilise), but each cell in the body has a particular function, for example, our muscle cells help us move and our immune cells help us fight off invading viruses.  To carry out these functions, these cells need certain nutrients.  Whilst some of these nutrients can be made in our bodies, others must come from our diet.  

Not surprisingly we also have certain cells and chemicals that help us feel and behave and the same concept applies to them – in short, what we eat can influence how we feel and behave. 

So, are there certain foods that can boost our mood?  Well, yes there are, but let’s get a handle on how this happens first.  

How does food affect our behaviour?

We have direct influences on our mood and behaviour, and this largely depends on chemicals known as neurotransmitters.  Neurotransmitters are like our body’s carrier pigeon; they send messages all around to help us function.  But they are thankfully a little quicker than a pigeon.  

Neurotransmitters can either be inhibitory or excitatory, this means they either make something happen or stop something, we can think of them as our in-built gas pedal and brake.

You will likely be familiar with some of our neurotransmitters; dopamine, norepinephrine, and serotonin, but others that do their share of the work include histamine, glutamate, acetylcholine, and gamma-aminobutyric-acid or GABA.  Don’t worry there’s not a test to remember their names, we’re more interested in their roles.  

Neurotransmitters and their roles 

Dopamine is well known for its role in focus and attention, but it also plays a role in rewards and pleasure-seeking.  

Serotonin is known for being the happy chemical – serotonin levels are often diminished in those who are depressed.  This is why SSRI’s or their full name; selective serotonin reuptake inhibitors are prescribed as anti-depressants.  These medications prevent the reuptake of serotonin, meaning it lingers around longer to have more of an effect.  

Norepinephrine is part of the stress response which increases heart rate and mobilises energy to be used.  

GABA is like the brakes of our body – it helps us sleep, reduces mental and physical stress, lowers anxiety, and creates a calmness of mood. 

We need all of our heavy lifting neurotransmitters to help us deal with daily life; for us to be focussed and alert when needed and then able to rest and relax too!  

Where do we get them from?

Most of our neurotransmitters are made up of amino acids – which are the building blocks of proteins.  For example, dopamine is made from phenylalanine and tyrosine.  The names again aren’t important, but you find these amino acids in foods.  Sources of phenylalanine include dairy, eggs, nuts, chicken, beef, pork, and fish.  Sources of tyrosine include chicken, turkey, fish, bananas, yoghurt, pumpkin seeds, and sesame seeds.  GABA’s recipe includes an amino acid too, glutamine.  Sources of glutamine include beef, chicken, dairy, fish, eggs, cabbage, spinach, carrots, kale, and papaya.  

Serotonin is synthesised from tryptophan, but you probably already knew this!

However, in times of stress, tryptophan gets stolen.  We’re not lying.  It’s called the tryptophan steal, it’s like a less glamourous version of the cha-cha slide.  

Tryptophan feeds another pathway in the body, known as the kynurenine pathway which is a necessary pathway, but in times of stress or inflammation, this pathway steps up a notch and siphons the little tryptophan we did have!  For this reason, when we are feeling particularly stressed, it’s even more important to stock up on tryptophan-rich foods!

Foods to boost serotonin:

  • Banana
  • Pineapple
  • Pomegranate
  • Strawberry
  • Spinach
  • Nettle
  • Kiwi
  • Lettuce
  • Tuna
  • Turkey
  • Chicken 
  • Oats
  • Nuts and Seeds

But these amino acids are only part of the recipe.  We also have co-factors, which we can think of like seasonings. 

Some of the key nutrients involved in neurotransmitter synthesis include:

  • Vitamin B6
  • Vitamin B12
  • Folate/Folic Acid
  • Vitamin C
  • Zinc
  • Magnesium

In the synthesis of serotonin, tryptophan is converted in the presence of pyridoxal phosphate (PP).  This is the active form of Vitamin B6.  Because it is involved in the assembly and breakdown of carbohydrates, proteins, and fat, it is one of the most valued and recommended nutrients and one of the most well-researched.

However, it is also utilised in the synthesis of norepinephrine, which is part of our stress response – so the more stressed we are, the more norepinephrine we use and the more B6 we use up in the process.  

Great sources of B6 include pork, poultry, beef, liver, bananas, sunflower seeds, walnuts.  

The same concept applies to vitamin B12 also.  The more stressed we are, the higher the turnover, and so we need to stock up.  There are no known naturally occurring bioactive forms of B12 in plant sources.  This is because B12 is synthesised by the bacteria in the gastrointestinal tract of animals, and then absorbed by the host animals.  B12 is concentrated in their tissues, which is then eaten by other animals.  Sources of B12, therefore, include red meat, fish, dairy, and eggs.  Or if you are vegan/vegetarian, then a supplement is necessary.  Opt for a supplement in its methylated form, however.  

A deficiency in B12 often results in a functional folate deficiency due to their complementary roles, which is why filling your diet with folate-rich foods is crucial.  Folate or folic acid comes from the Latin folium, which means leaf, simply because it was first found in spinach.  Because of the role in neurotransmitter synthesis, there are often signs of irritability, poor cognition, and mood alterations in a folate deficiency. Sources include spinach, kale, and liver.  (i)

Zinc and Magnesium

Known as the ultimate chill pill, the body needs magnesium to create neurotransmitters.  Low levels of magnesium have regularly been linked to memory difficulty, poor concentration, depression, apathy, fatigue, irritability, emotional instability, nervousness, and anxiety.  Chronic stress depletes magnesium levels, so the more stressed we are, the greater the loss of magnesium and so the cycle continues.  Sources of magnesium include nuts, seeds, whole grains and green leafy vegetables. 

Zinc is regularly implicated in mood disorders.  It appears to have its biggest affinity with glutamatergic neurons, going as far as being called zinc enriched neurons.  Glutamate is the major excitatory neurotransmitter in the body, meaning it makes things happen, so it stands to reason that low levels of zinc are regularly implicated in cases of depression.  When zinc is supplemented, depression scores significantly reduce.  Whole grains and milk products are great sources of zinc, along with oysters, nuts, seeds, and legumes.  

The bottom line is that there are certain chemicals in our body that help us feel and behave the way we do, but they must be built from something.  They all have compounds and whilst some can be made in the body, the majority come from the diet.  So, ensure you have a diet rich in protein and a range of micronutrients, like B Vitamins, Vitamin C, Zinc, and Magnesium. 

But this is only part of the story.  

There is another way in which what we eat affects how we feel and behave.  This is known as the gut-brain axis, or we can liken it to a highway between our gut and brain.  

One of the ways our gut communicates with our brain is through the community of microbes that it houses.  The microbiome is made up of trillions of bacteria which carry out a range of roles from synthesising certain nutrients to keeping harmful bacteria in check.  But they also produce a range of compounds that talk to our brain.  These compounds are known as short-chain-fatty acids or SCFA’s.  These SCFA’s, especially one known as butyrate is often implicated in cases of depression; low levels often result in higher scores of depressive symptoms.  To produce these SCFA’s, the microbes in our gut ferment fibre.  

For that reason, a fibre-rich diet could be one of the single most important changes you make to improve your mood. 

Adults should ideally get 30g of fibre in their diet every day, but in the UK, most of us only get to 18g!

Sources of Fibre:

  • Wholemeal spaghetti (4.2g fibre per 100g)
  • Strawberries (3.8g fibre per 100g) 
  • Parsnip (4.7g fibre per 100g)
  • Almonds (7.4g fibre per 100g) 
  • Peas (5.6g fibre per 100g) 
  • Sunflower seeds (6g fibre per 100g) 

As you can see, fibre can be found in nuts, seeds, and vegetables and now, we find many food items enriched with fibre.  

Fibre is an undigestible carbohydrate and increasing evidence suggests that those who regularly consume a fibre rich diet are less emotionally distressed, have fewer cognitive difficulties, have more positive moods, have less difficulty falling asleep and have lower depression scores.  (i)

So there we have it, food really can influence how we feel and behave.  Remember it’s not just about including all these nutrient-dense foods in your diet, it’s about reducing how many nutrient-poor foods we eat too.  When we eat something nutrient deplete, our body still has to do something with it, so it uses valuable resources, enzymes and co-factors to do so and all these co-factors and enzymes could really be used for other things.  So not only are we not getting much from these foods, we’re almost putting our body in a nutrient debt to deal with them too!