The pervasiveness of diet culture in the world today teaches us that we must create rigid rules around our consumption of food, and we must feel guilt and shame when we break those rules. We certainly must not allow ourselves to enjoy food (unless it checks all the boxes of what we believe counts as “healthy”).
On the other hand, the intuitive eating approach tells us that for the sake of our health, we must reject all diets and the limiting food rules that cause us to distrust our bodies' innate sense of our needs. Instead, we are told to eat when, where, and we want.
On the other-other hand, the mindful eating approach tells us that we must focus more on food while we eat, tune into our hunger and fullness cues and learn to truly appreciate our food for the nourishment it gives us, as well as the taste, texture, scent, etc.
Yet we all know that there are some nutrients that we need more of, and some nutrients that are better for us to eat less of. We all know that some foods are filled with more of the nutrients we need more of, and those are the foods we consider "nutrient-dense," while others are just kind of empty of most of those nutrients, and others are pretty high in the nutrients we know we should be eating less of. Other foods might be processed in a way that, when eaten regularly, is known to be harmful to our health.
So does being anti-diet mean that we are also anti-health? Does intuitive eating mean that we believe that we can really subsist on Oreos all day, every day if that’s what we’re craving? And where does mindful eating fit in? Is it okay to diet as long as we’re eating mindfully?
Sometimes having so many different terms wrapped around a topic can create a lot of confusion. There is a lot of overlap, for example, between mindful eating and intuitive eating, and there actually can be a fair amount of overlap between mindful eating and diet culture, as well. The terms themselves can be useful to help us understand the concept, but just like labeling your diet as “plant-forward,” “vegetarian,” “vegan,” or “pescetarian,” the terms can become somewhat limiting. There are often reasons to incorporate multiple approaches and to be flexible in our lives and in our diets.
It can be helpful to use terms and labels to learn about a topic or to explain it to others, but it can also be helpful to lose the terms sometimes, and just explain things as we see them. So, here’s how I see it.
I believe that rigid rules and restrictions around food can be harmful to the mental and physical health of the people who believe in them (whether or not they actually adhere to them). I think these rules can damage their relationship with food, with their own bodies, and their relationships with others.
I believe that good nutrition includes nourishing the body and the mind – both from a biological perspective and from an experiential and psychological one.
We nourish ourselves by eating food that contains the nutrients that our bodies and brains need for good health.
But we also nourish ourselves by spending time eating food with others – we build relationships through and around food and eating.
We also nourish ourselves by listening to our bodies’ cues of hunger and fullness; respecting our bodies enough to give them energy and nutrients when we feel those cues of hunger and sitting back from the table to allow comfortable digestion of those nutrients when we feel that sensation of fullness.
We also nourish our bodies and minds through mindful enjoyment of the experience of eating and being fully present in the moment, without the accompanying guilt and shame of over-attentiveness to food and eating that is often present when dieting. (When I first started teaching classes on mindful eating, I used to use the formula Mindfulness = Awareness – Anxiety to explain this concept.)
We also nourish ourselves through the gratitude that we feel and express when we eat mindfully, as we recognize all that went into bringing our food into existence and onto our plates, and the incredible process by which our bodies will use the components of that food to rebuild, grow, and fuel the living of our lives!
As Thanksgiving approaches this year, I encourage you to try to shift your focus away from “shoulds” and “shouldn’ts,” and towards gratitude for the food in front of you, the people around you, and the body that carries you through the world.
What do you think about these terms and other common terms surrounding our relationships with food? Leave me a comment and let me know! And if you’d like more personalized guidance, schedule an appointment with me! I’d love to work with you.
(To get some background on this topic, you may want to start here with my post discussing the gut-brain axis in more detail.)
Assuming we're all on the same page that the health of our "second brain" is vital to our mental health, let's jump right into some of the factors that influence the gut-microbiota-brain axis, and the places where we can have an impact through nutrition and lifestyle.
he Microbiome, Probiotics and Prebiotics
One of the most dramatic changes in the perspective of medical science in the past 20 years has been the shift in the way we view bacteria. We’ve shifted from the hygiene model (where the more sterile we could make our environment, the better) to understanding that we not only have massive numbers of microbes (bacteria, fungi, and viruses, etc.) inside and outside of our bodies at all times, but that we actually need and benefit from them.
Unfortunately, the traditional Western-style diet is pretty deficient in the favorite foods of those healthy gut bacteria: fibers (also called prebiotics).
While there are lots of things that influence our gut microbiome that we don't have much control over, there are also some pretty substantial things that we do have control over, and research has shown that the impact of some dietary changes can be seen as soon as 2-4 days - though it takes much longer to have a substantial and lasting impact.
The foods we eat and the types of fibers that they contain can have a direct impact on which kinds of microbes flourish in our intestines, and which types don't. Eating foods that contain healthy bacteria (also called probiotic foods – things like yogurt with live and active cultures, sauerkraut, and miso) can also have a positive impact.
And in turn, promoting the growth and flourishing of these healthy bacteria has been shown to increase their production of the neuroprotective short-chain fatty acid butyrate, improve our stress response, optimize immune function, impact neurotransmitter function in the brain, decrease symptoms of depression, alleviate anxiety in children with autism spectrum disorder, and more.
The importance of nutrition - adequacy of energy (calories), vitamins, minerals, amino acids, fiber, essential fats, and carbohydrates - really can't be understated when it comes to mental health.
When it comes to good nutrition, calories are just the beginning. Even the macronutrients (carbohydrates, protein, and fat), while very important, are just the beginning. Most of us get enough of these things in general (though we’ll talk more about the specifics of types of protein and types of fat in a minute).
But what about vitamins and minerals? Many of us tend to eat diets that are full of a lot of processed foods which are energy-dense (plenty of calories) but nutrient-poor (depleted of a lot of the vitamins and minerals that whole foods, like produce, meats, fish, beans, nuts and seeds, etc. contain). We often don’t eat enough fruits and vegetables - and especially vegetables.
Eating diet rich in whole plant foods (and maybe even growing our own when we can, for optimal nutrient quality and a healthy connection to nature) goes a long way towards getting us the essential vitamins and minerals that we need, as well as the fiber to feed that lovely gut microbiome.
But for some people, it seems that even a nutrient-dense diet doesn't go far enough to meet their nutrient needs. For a variety of reasons, some people have higher needs for certain vitamins and minerals than we might think based on the estimates of the RDAs (i.e., the percentages listed on the nutrition label).
A growing body of research is showing that increased needs for certain vitamins and minerals, especially things like B vitamins, vitamin D, magnesium, and zinc, might be linked to certain mental health conditions.
Amino acids are the building blocks of protein molecules, and there are 9 that are considered essential – meaning that we have to eat them in our diets because our bodies can’t make them.
Amino acids are also the precursors for neurotransmitters in the brain. Seven of the essential amino acids are also essential for making neurotransmitters: valine, leucine, isoleucine, lysine, phenylalanine, histidine, and tryptophan. Diets that are deficient in these amino acids can cause deficiency of neurotransmitters – things like GABA, serotonin, and dopamine – and can cause mental illness-like behavior.
It’s worth noting that amino acids are also the major fuel of the cells of the intestines, so deficiency in amino acids not only affects the brain and neurotransmitter levels directly, but also via the gut-brain axis, as poorly-nourished intestinal cells aren’t able to continually replicate and renew the gut lining the way that they need to.
Omega-3 Fatty Acids
One widely-studied nutrient group is the polyunsaturated fatty acids, including omega-3 and omega-6 fatty acids. While some amounts of each are essential for our health, omega-3 fatty acids are known to decrease inflammation, and they also seem to play a role in promoting a healthy gut microbiome.
Most of us eat far more omega-6 than omega-3 fats. Eating more nuts (especially walnuts), seeds (especially flax seed), and low-mercury fatty fish (like anchovies, salmon, or halibut) can help us improve our omega-3 fatty acid intake.
While supplementing with omega-3 fatty acids (like DHA and EPA) has produced mixed results in clinical trials, we do see a clear benefit to mental health from eating foods that contain omega-3s.
In the case of supplements, there does seem to be a benefit to supplements with the right ratio of EPA to DHA for some people with major depressive disorder, schizophrenia, and bipolar disorder, but it’s always a good idea to consult with a doctor, psychiatrist, or dietitian with expertise in nutritional psychiatry to help decide whether a supplement is right for you, what dosage, and what ratio of EPA to DHA, as this varies depending on the person and depending on the diagnosis.
Polyphenols are anti-inflammatory compounds found in plant foods such as grapes, pears, berries, cherries, tea, cocoa, legumes, grains, coffee, and apples. Resveratrol and curcumin are two well-known examples of polyphenols.
The majority of these compounds are actually fermented by the gut microbiota first to allow our bodies to absorb and use them, and they play a role in preventing dysbiosis - promoting a healthy balance of bacteria in our intestines.
Polyphenols have been shown to reduce inflammation, protect the brain from cellular damage, play important roles in learning and memory, and balance neurotransmitter levels in the brain.
Inflammation and mental illness are inextricably linked. While we used to think that inflammation in the rest of the body had no impact on the brain, shielded as it is by the blood-brain barrier, we now know that systemic inflammation (both acute and chronic) has a significant impact on the functioning of the brain. So, managing inflammation with tools like the Mediterranean or other anti-inflammatory eating patterns is important in managing mental illness.
Several wonderful studies have been done on variations of the Mediterranean diet in improving mental health and reducing symptoms of depression. It’s worth noting that polyphenol-rich olive oil is a key component of the Mediterranean diet, which may be part of why it’s so effective in improving mental health, along with the emphasis on nutrient-dense foods, omega-3-rich fish, nuts and seeds, and plant fibers.
Food Allergies and Sensitivities
For some, food allergies and sensitivities can be significant causes of inflammation, both in the gut and in the body as a whole.
When we eat foods to which we are allergic, our bodies respond as if we’re at war, with a massive inflammatory cascade that seeks to destroy the enemy invader - and ends up damaging our own body tissue and possibly even threatening our lives.
While less severe, food sensitivities have been found to have some negative long-term health impacts on people who eat significant amounts of these foods to which they are sensitive. The gut can become inflamed and irritated, which can cause some obvious side effects like diarrhea or abdominal pain for some, in addition to causing the tight junctions between the intestinal cells to open up and allow molecules that are a bit too big to come through. (This is called intestinal permeability, though it’s been nicknamed “leaky gut.”)
This can contribute to inflammation throughout our bodies and brains, change the composition of our gut microbiome, and possibly even contribute to a “leaky” blood-brain barrier.
Rates of food allergies and sensitivities are known to be increased in children with ADHD and individuals with schizophrenia, for example, and there are also high rates of depression and anxiety in people with severe food allergies – though the cause or connection is still unclear.
Though it doesn't totally fall under the umbrella of the gut-brain axis, exercise is worth mentioning anytime we talk about mental health and lifestyle change. Exercise has been dubbed by some the "best anti-depressant." It doesn't require skill, money, or even much of a time commitment. Anyone can do it from anywhere, and it's incredibly effective in improving mood, reducing symptoms of depression and anxiety, improving sleep (which itself is important in stabilizing mood), and more.
Along with its many, many other health benefits, exercise also influences the gut microbiome. Exercise can increase the numbers of "good" bacteria, as well as boost the diversity of microbes in your gut.
While there are lots of dietary and lifestyle factors that we already know influence our gut microbiome, it’s a relatively new field, and we're probably only just scratching the surface so far!
But if you want to make some concrete changes to improve your gut health and mental health, here are some ideas for where to start.
If you have any questions, feel free to comment below or message me directly. If you’d like more personalized guidance, schedule an appointment with me! I’d love to work with you.
In order to talk about the gut-brain axis, we have to start with a basic understanding of the gut and of the brain.
(As an aside, I believe health literacy, or understanding what's going on inside your body, is so, so important in understanding when and why things go wrong, making educated decisions on how to manage things on your own, and knowing how and when to seek treatment when it's needed. So try to stick with me if you can!)
In case it's been a minute since biology class, let's start with a brief review of the process of digestion.
When you eat, food moves through your mouth, where the process of digestion starts, down your esophagus, and into your stomach.
While there, acidic digestive juices work on breaking it down chemically, while the rhythmic motions of your stomach work on breaking it down physically. When it's ready, it moves next into the small intestine.
The small intestine is narrow, but it's incredibly long (approximately 22 feet!) and covered in microvilli, small hair-like projections on the surface of the intestinal epithelial cells that make its surface area somewhere in the neighborhood of 2700 square feet. All this surface area is vital to getting as many nutrients as possible absorbed from your food into the blood, including broken-down carbohydrates (monosaccharides), amino acids, fatty acids, vitamins, and minerals.
What isn't absorbed in the small intestine keeps on moving and ends up in the large intestine - which is a comparatively measly foot-and-a-half in length, but much wider. In the large intestine, the body focuses on absorbing water and a few last nutrients, like electrolytes, biotin, and vitamin K.
Most of the digested food that enters the large intestine has been reduced to fiber, water, and waste products. Fiber is actually a type of carbohydrate that our bodies cannot digest.
Fortunately, our large intestines are filled with critters that can digest that fiber - our intestinal microbiota. Our bacterial friends ferment (break down) fibers from plant foods that we eat into energy for themselves, and into short-chain fatty acids (SCFAs) for us. These short-chain fatty acids, like butyrate, proprionate, and acetate, are things that we can't produce for ourselves, but that become the main source of energy for the cells lining our large intestines (among other important functions).
By the time the continued rhythmic movements throughout your intestines have brought the waste products to the end of the line, it's been a couple of days - approximately 5 hours in the stomach, 5 hours in the small intestine, and anywhere 10-70 hours in your large intestine.
While you are focused on chewing and swallowing, your body and brain are hard at work sending and receiving messages. Multiple hormones are released by the stomach, the small intestine, and the large intestine as the food you're eating moves through your digestive system. Other digestive organs, like the pancreas and liver, are activated, and send in enzymes to help with the process of breaking down foods into their nutrient components.
After you eat, the vagus nerve, the longest and most complex of all the cranial nerves, lights up with communication between your brain and your gut, as your digestive system reports back to the brain on the meal you are digesting.
The nutrients absorbed into the body, including vitamins, minerals, amino acids, glucose (sugar), short-chain fatty acids, etc., as well as the hormones produced in the gut, can also themselves send messages to the brain. Some nutrients are able to pass through the blood-brain barrier (the "wall" separating the brain from the rest of the body and protecting it from harmful substances) into the brain, directly impacting brain function (things like increasing or decreasing levels of different neurotransmitters, increasing or decreasing inflammation in the brain, increasing or decreasing different hormones... etc.).
Additionally, problems in the gut (such as irritation and inflammation) are communicated to the brain and can lead to some pretty dramatic shifts in mood, cognition, stress, and anxiety.
This connection between the gut and the brain is obviously very complex - much more so than we can address in this one blog. But the constant two-way communication happening between these two important body systems is part of why the gut has begun to be called the "second brain" or the "gut brain" - technically known as the enteric nervous system.
It's clear from the research that we have to stop thinking about mental illness as being "all in the brain." The gut-brain axis is just one example of how interconnected all of our body systems are.
Say it with me:
Mental health is HEALTH.
Want to learn more? Reach out. I'd love to work with you. And if you're interested in future posts, be sure to sign up for updates or check back soon for more to come on strategies for using our "gut brain" to improve the health of our "main brain."
Erica Golden, RDN