This Is Your Brain on Food

you wake up feeling exhausted – your mind foggy, your mood unpredictable. you chalk it up to stress, lack of sleep, or just another bad day. but what if the real culprit is on your plate?

for centuries, we’ve understood that food fuels the body, but only recently have scientists begun to grasp how deeply it shapes the mind. the gut – often dismissed as a simple digestive system – is actually a powerhouse of chemical production. it directly influences emotions, focus, and even mental health conditions like depression and anxiety. the connection between what we eat and how we feel isn’t just a wellness trend – it’s a scientific reality.

it’s time to rethink what’s on our plates – not just for physical health, but for mental clarity and well-being. in this chapter, we’ll focus on the impact of food on four mental health conditions – specifically what to eat, and what to avoid, if you have depression, anxiety, adhd, or insomnia.

but first, we need to understand what’s beneath it all – the close connection between the gut and the brain. let’s find out.

“bad digestion is the root of all evil.” that was the opinion of hippocrates, a famous physician who lived in ancient greece.

hippocrates recognized that there was a relationship between the gut and the brain. but it seems that modern psychiatry is still catching up, as we’re only just beginning to understand how important this connection is.

the brain and gut are physically connected. they’re linked by the vagus nerve – the communication channel between the two. this channel works both ways – the brain sends chemical messages to the gut, and vice versa.

but that’s not where the connection ends. these days, there’s increasing interest in the role of the gut microbiome. to put things simply, the gut is full of different species of bacteria. these bacteria help to produce brain chemicals, including dopamine and serotonin – chemicals which are essential for regulating mood, among other things. 

so, if the gut bacteria is abnormal for whatever reason, it’s going to affect our mental health. and by that logic, we need to take care of our gut, which means – you guessed it – paying close attention to our diet.

right now, more than 40 million americans are dealing with a mental health issue. anxiety and depression are on the rise. so, as the science shows that diet can affect mental health – and that there’s a direct link between an altered microbiome and disorders such as depression – isn’t it worth looking into?

in the following sections, we’ll explore some food-related recommendations for specific mental health conditions. while what you eat isn’t everything, it’s a significant part of the puzzle.

ted was stressed and depressed. and when his mood was low, ted often found himself turning to comfort food – vending machine snacks, chocolate, a glass of wine or three. 

his primary doctor had recommended prozac, but when ted consulted psychiatrist and nutrition specialist uma naidoo, she had a different idea. she suspected that ted’s diet was contributing to his low mood.

unfortunately, the very things we feel like eating when we’re depressed – such as sugary treats and fried food – actually make us feel worse.

as we mentioned before, our gut bacteria influence the chemical messages received by our brain. so, it’d make sense that people who are depressed have different gut bacteria.

and indeed, that’s what the research suggests. multiple studies looked at the gut bacteria of patients with major depressive disorder. it turned out that these people had more than fifty types of gut bacteria species that were different, compared to the gut bacteria of people who weren’t depressed. 

so, if you’re suffering from depression or low mood, it may well have something to do with your gut. in which case, it’s time to make some dietary changes. let’s take a look at naidoo’s recommendations.

first, what not to eat. avoid overindulging in sugar, artificial sweeteners, and high-gi carbohydrates such as potatoes, white bread, and white rice. fried foods, and trans fats such as margarine and hydrogenated oils, will also dull your mood.

the good news is there are specific foods you can add to your diet to improve your mood. omega-3 fatty acids are great mood boosters, and can be found in fish like salmon, tuna, and sardines.

also, make sure you’re getting plenty of vitamins and minerals. in particular, look for foods that contain folate and vitamin b12, such as legumes, citrus fruits, and leafy greens.

you should also consider adding prebiotics and probiotics to your diet, as they can help keep your gut healthy. prebiotic-rich foods – which include berries, garlic, and onion – make probiotics more effective. good probiotics include sauerkraut, kefir, and kimchi.

finally, as a general approach to fighting depression, look into the mediterranean eating pattern. it’s a flexible, plant-based diet with an emphasis on seasonal fruits and vegetables, and minimally processed foods. while anyone can benefit from this healthy diet, it’s particularly helpful for people with depression.

before we move on, let’s go back to ted. following naidoo’s recommendations, he changed his diet, swapping unhealthy snacks for things like walnuts, hummus, fruit, and vegetables. after a while, he stopped craving junk food.

and although he lost weight, the main difference was his mood. thanks to his diet, ted now felt bright and energized – no longer depressed.

now, let’s explore a condition that often goes hand in hand with depression – anxiety.

anxiety is incredibly common. it’s estimated that in the united states, as much as a third of the population suffers from an anxiety disorder at some stage during their life. 

and unfortunately, traditional treatments, such as psychotherapy and medication, only work for about 50 to 60 percent of people.

so, let’s consider the link between anxiety and the gut. this is something we can all understand. there’s a reason why we talk about “butterflies in your stomach” when someone’s feeling nervous.

and again, the science suggests that there’s a link. there’s a strong correlation between anxiety and bowel disorders such as irritable bowel syndrome, or ibs.

so, let’s take a look at our diets, and the foods that are known to increase anxiety.

one of the biggest culprits is the so-called western diet, which actually refers to the standard american diet. a high-carb, high-fat diet with lots of red meat and sweetened drinks is generally unhealthy, and particularly bad for those of us with anxiety.

excess caffeine can also trigger or worsen anxiety. and alcohol – so often used as a coping mechanism – isn’t as relaxing as we like to think. in the moment, a drink feels good, but the next day, even mild alcohol withdrawal can leave us feeling jittery.

another thing to watch out for is gluten. some research suggests that there may be a link between celiac disease and anxiety. so if you suffer from anxiety, it might be worth getting tested for celiac disease, or giving up gluten for a while to see if your mental health improves.

to relieve anxiety, make sure your diet is rich in high fiber foods – beans, brown rice, carrots and broccoli, and fruits like pears, apples, and bananas. fish and seafood rich with omega-3s can also make a difference. and so can aged, cultured, or fermented foods – things like yogurt, kimchi, and kombucha.

finally, make sure you’re getting plenty of vitamins and minerals – in particular, vitamin d and magnesium.

whether you’ve been formally diagnosed with anxiety or you’re just feeling a little on edge, it’s definitely worthwhile making some changes.

the connection between the gut and anxiety might seem fairly intuitive. more surprising, perhaps, is the link between gut bacteria and attention deficit hyperactivity disorder, or adhd.

but actually, it makes sense. adhd is the result of chemical imbalances in the brain. and it’s gut bacteria that are responsible for synthesizing certain chemicals, like those that help create dopamine, for instance. studies have revealed differences in the gut microbiomes of those with adhd, and those without the condition. 

there definitely appears to be a link. and considering that adhd is often resistant to treatment, it’s all the more important to think about diet.

so, if you have adhd, here’s what you need to know. foods believed to worsen symptoms include gluten and dairy. the issue with dairy is that it’s high in a protein called casein. if you don’t want to cut out all dairy, look for milk products that are high in a2 protein instead. sheep’s and goat’s milk are usually better options. also, try to limit your intake of sugar, and food containing colorings and additives.

what should you eat instead? earlier, we mentioned the mediterranean eating pattern. as well as being generally healthy, it can also improve adhd symptoms.

certain foods also help with focus. look out for polyphenols, which can be found in berries, eggplant, and onions, as well as coffee and green tea. while you shouldn’t overdo the caffeine, it can be helpful in moderation.

lastly, a word on medication. drugs such as ritalin and adderall can be beneficial for some people, but they aren’t without risk. if your adhd symptoms are mild, try altering your diet first, and see if this helps calm your mind and improve your focus.

speaking of calming your mind: do you toss and turn each night, struggling to fall asleep? if so, you’re not alone – about one in three of us have sleep issues. and once again, there’s an undeniable link with what’s going on in our gut.

all living creatures have a natural sleep cycle, including the bacteria that live in the gut. when your body’s internal clock is out of sync – after a few late nights, or when you’re jet-lagged – it can affect the behavior and composition of your gut bacteria. it can even change how you metabolize food, potentially leading to obesity. 

there’s a reason why shift workers, with their irregular sleeping patterns, often tend to have weight issues. and that’s just scratching the surface. 

if you’re suffering from insomnia or general fatigue, you might already have a sense that something’s not quite right in your stomach. either way, let’s look at what we can change.

the first tip probably comes as no surprise – cut down on caffeine and alcohol. they’re both known for disrupting sleep. ideally, limit yourself to four small to medium cups of tea or coffee a day, and don’t have any caffeine after 3pm. 

as for alcohol, although some people use it as a sleep aid, it actually disrupts the normal sleep cycle, leading to poorer quality rest. try abstaining for a month and see if you sleep better.

you can also experiment with some dietary changes. try eating more fatty fish, like salmon and tuna, which contain omega-3. and how about adding some melatonin to your diet? the sleep hormone can be found in many different foods, including eggs, fish, nuts, and seeds.

some foods are also useful for fighting fatigue, in particular, anti-inflammatory foods such as omega-3s, and colorful vegetables. also, make sure you’re getting enough magnesium, zinc, and vitamins – particularly the b vitamins, but also c, d, and e.

by this point, you’re probably starting to see a pattern emerge. for improved mental health, a varied, healthy diet makes all the difference. make sure you’re getting a bit of everything.

even if you don’t have a specific condition, most people can improve their mental health by making small dietary tweaks. 

firstly, what they say is true – don’t shop when you’re hungry. you’re more likely to fill your cart with non-nutritious comfort food.

instead, make an active effort to stock up on healthy food. try to remember the acronym “brain foods,” where each letter stands for a type of food.

b is for berries and beans. r is for a rainbow of colors, in terms of fruit and vegetables. a is for antioxidants.

i is for include – include lean and plant-based proteins. n is for nuts, while f is for fish, fiber-rich and fermented foods. o is for healthy oils, like olive oil. then another o for omega-3-rich foods. 

next, d for dairy – particularly yogurt and kefir. and finally, s for spices.

so remember – “brain foods.” stock up on those ingredients, and you’re off to a great start.

before we wrap up, there are a few other things to keep in mind. as we mentioned earlier, a variety of color is important for fruit and vegetables. but the most important color is dark green. make sure you’re getting plenty of leafy greens like arugula, endive, and bok choy.

lastly, don’t be afraid to push yourself. experiment with new ingredients and new recipes. keep those general principles of healthy eating in mind, and you can’t go wrong. you might discover some new favorite foods. and as eating healthily becomes a pleasure, your brain, as well as the rest of your body, will feel the difference.

in this chapter to this is your brain on food by uma naidoo, you’ve learned that the gut and the brain are closely connected. our gut bacteria help produce brain chemicals like serotonin and dopamine, which influence mood, focus, and even sleep. so, if you have a mental health condition, it might be time to make some changes to your diet.

for depression, cutting out sugar, processed foods, and trans fats while adding fish and probiotics can boost mental well-being. anxiety sufferers should avoid caffeine, alcohol, and gluten while opting for fiber-rich foods, seafood, and fermented products.

adhd may also be linked to gut health. reducing dairy, gluten, and artificial additives while following a mediterranean-style diet with polyphenol-rich foods like berries may help with focus. 

people struggling with insomnia should avoid caffeine late in the day, try cutting out alcohol altogether, and eat foods containing omega-3 and melatonin.

even if you don’t have a mental health condition, eating more “brain foods” – including berries, nuts, fish, and leafy greens – can enhance overall well-being. 

food isn’t a cure-all, but it plays a crucial role in mental health. small dietary changes might just transform how you feel.

okay, that’s it for this chapter. we hope you enjoyed it. if you can, please take the time to leave us a rating – we always appreciate your feedback. see you in the next chapter.