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Why is nutrition not often linked with mental health?

With more and more education abounding about the prevalence of mental health, it’s surprising that the link between our nutrition and mental instability hasn’t become common knowledge.

For decades, we’ve known that mental health has various expressions and that the biochemistry of the body plays an important role in keeping our outlook cheery.  Unfortunately, when we’re talking about depression, and some of the more common day mental health imbalances, many people still believe that it’s “all in our head”.  That these conditions can be controlled by our willpower and psychology.

Before digging deeper into the link between our minds and our nutritional state, let’s take a look at how our brain responds to our biochemistry.

The brain has a protective system called the blood-brain barrier (BBB) that keeps unwanted cells and other pathogens out of the brain.  This BBB is equipped with its own immune system to even further protect the brain and its vital function.  The brain can also be considered one of the body’s largest endocrine organs as it is covered with receptors for steroid and thyroid hormones. The BBB, which allows the diffusion of these hormones into the brain, can even be considered endocrine tissue. With this base understanding, we can see why endocrine balance can influence our neurochemistry and an imbalance can put us at risk for mental dis-ease.

The BBB is a fascinating filter.  What is being studied, as we speak, is how inflammation affects the BBB.  Studies are showing that as the body experiences inflammation, the permeability of the BBB increases allowing unwanted substances to enter the brain causing neuro-inflammation.  Other things can independently contribute to neuroinflammation, too.  Elevated cortisol levels, elevated blood sugar/insulin levels, drugs and alcohol, and a leaky gut can weaken our BBB’s protective abilities.


What are the key nutrients to keep the brain active and healthy?

Assuming that we are absorbing what we eat, the key nutrients to a healthy brain are:

  1. The B Vitamins.  Although each B vitamin has its distinct role in brain health, the vitamins work best when taken together.  The adrenal glands also depend strongly on the B complex and they are the vitamins that are most depleted in times of stress.  You can find rich sources of vitamin B in egg yolks, nutritional yeast, black beans, lentils, mushrooms, salmon and sunflower seeds.
  2. Glutamine.  Glutamine is an amino acid that can easily pass through the BBB.  Because of this, it is considered brain fuel and is essential to cerebral function.  Glutamine also promotes the maintenance of a healthy digestive tract; a link we will be discussing later in this article.  Many plant and animal sources contain glutamine.  If eaten raw, spinach and parsley are a great source.
  3. Zinc. Zinc is required for protein synthesis and promotes a healthy immune system.  It plays an important role in so many enzymatic reactions in the body.  It supports the detoxification process that is so important in keeping our body and our brain healthy.  Pumpkin and sunflower seeds are high in this essential mineral.
  4. EFAs.  Our brain is primarily made of fat.  We need healthy fats to help our body and brain metabolize essential fat soluble vitamins like vitamin A, D, E and K.  Omega-3s are found in high concentrations in the nervous system, and the brain, where they are needed to build healthy cell membranes, reduce inflammation, promote new cell formation, form important brain chemicals, and improve nerve transmission.  Low levels of Omega-3s have been linked to anxiety, depression and bipolar disorder.  Omega-3s help so many different body systems and they are essential in our diet as the body cannot manufacture them.  High sources are found in salmon, flax, walnuts, cod liver oil and chia seeds.
  5. Serotonin.  Serotonin is considered to be the “happy hormone”.   When foods high in tryptophan are ingested, the body can create and increase its serotonin levels.   Foods high in tryptophan are bananas, walnuts, pineapple, turkey and cocoa.  What’s important to note, however, is that 95% of the body’s serotonin is produced in the gut.  Another link between the gut/brain connection.
  6. Turmeric.  This anti-inflammatory herb has been proven to reduce the symptoms associated with a major depressive disorder.   Turmeric’s properties can easily pass through the BBB to increase serotonin and dopamine levels in the brain.


What impact does junk food have on mental health?

We are learning more and more about the link between our gut health, a stable blood sugar balance and our brain health.  Unfortunately, the foods we tend to eat when we are feeling depressed or anxious do not lend themselves to a healthier gut, stable insulin levels and a calm mind.  In fact, foods like cookies, cakes, ice cream and other processed snack foods are some of the biggest culprits in leaving us imbalanced.

Let’s look at the gut/brain connection.

As researchers turn their microscopes towards our gastrointestinal tract, they are seeing an entire ecosystem of bacteria and a vast neural network operating in our guts. This ecosystem is now considered our second brain.  It comprises over 100 million neurons, more than the spinal cord, and mounting evidence suggests that our gut’s health strongly influences mood.  The enteric nervous system is a mesh-like network of neurons that lines the entire digestive tract. It causes the sensation of nervous butterflies or a pit in your stomach that are innate parts of our psychological stress responses. Up to 90% of the cells involved in these responses carry information to the brain making your gut an influential part to your mood.

Inside the digestive system, the enteric nervous system mainly communicates with bacteria that make up our microbiome, and there are just as many bacteria in our microbiome as there are human cells in our body.  This microbiome helps digest food and fight off unfriendly outsiders like viruses and molds. To keep us healthy, they need to be healthy and plentiful. When they’re not, we feel it.  This biomass of bacteria communicates with important neurotransmitters embedded throughout our enteric nervous system to send messages that influence the way we feel.  There is evidence that a healthy gut can curb inflammation and cortisol levels, lower your reaction to stress, improve memory, and even reduce neuroticism and social anxiety.  Studies indicate that those with healthy and diverse gut microbes are less likely to suffer from depression or anxiety.

So, changing one’s diet to support gut-friendly bacteria could benefit more than just your digestive symptoms but also improve your mental health.


What are some of the best ways to support your gut-friendly bacteria? 

The unfriendly bacteria in our gut loves sugar.  Any form of sugar.  Simple carbohydrates, alcohol and refined carbs are some of the best foods to feed our “bad” bacteria.  To heal your gut, you want to focus on whole grains and foods that your healthy bacteria can feed on.  Probiotic foods, or fermented foods, are some of the best ways to increase your healthy gut bacteria.  Plain Greek yogurt, tempeh, unpasteurized sauerkraut, kimchi or even kombucha are foods that will provide your body with an array of bacteria that will help your microbiome flourish.  Foods high in fiber can also help your body increase its healthy bacteria.  Jerusalem artichokes, asparagus, leeks and onions are a good choice.


Are there any other things we can do to improve our brain function?

When we are looking at a nutritional assessment of brain function, we like to ensure that your body is non-toxic, and your inflammation is within a normal range.  Ensuring that your liver and digestive system are working well is a great way to help support your body’s natural detoxification systems.  Liver friendly foods include arugula, dandelion greens, lemons and limes.  Antioxidant-rich berries are also an added nutritional boost and will help your body destroy oxidative stress.  Your digestive system will benefit from a diet low in refined and simple carbohydrates.  Ensuring that you have enough stomach acid to process and chelate toxins are also important when we are supporting your digestive health.  If you are not certain if your digestion is optimal, please reach out to us and we’ll give you more tips on how to best digest your food.

Eating at regular intervals will also ensure that your blood sugar levels remain stable.  High peaks and valleys of blood sugar will create a cascade of insulin and other hormonal responses that affect the permeability of your BBB.  Eat small meals every 3 to 4 hours which include healthy proteins, fats and complex carbohydrates coming mainly from plant sources.

Also investigate possible food allergies to gluten, soy, dairy, peanuts and corn.  Food allergies can create inflammation and digestive distress that we may not recognize immediately.  A food journal may be a great way for you to notice the symptoms you may experience after eating your meals.  Write down your meals and snacks and then track how you feel afterwards.  Do your foods make you sluggish?  Do you get gassy? Do you have more energy?  These are great tools for you to start to notice the effects of your nourishment.

And finally, lessen your stress.  We are now seeing how cortisol can decrease the amount of tryptophan in the brain and how chronic stress can trigger long-term inflammatory responses.  Our body likes to be in homeostasis.  It likes to be healthy.  When we are experiencing symptoms of depression, anxiety or other mental health imbalances, this is a signal for you to pay more attention to your body’s needs.  With time, focus and professional help, you can return to a state of balance and a cheery disposition.



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