The world is going through a very challenging time and everyone is dealing with different struggles, and for some of us that can have a heavy impact on mental health. Also, Poor diet is the leading cause of health burden across the world. It is the leading cause of premature death in men and number two in women because of changes to our global food systems. I started studying nutrition after learning this eye-opening statistic because I wanted to make a positive difference in people’s lives and improve the quality of our years on earth. I am sure many others can relate when I describe my own significant decline in mood, energy levels and overall productivity since COVID-19 and isolation began. You are not alone in this struggle right now. Mental well being is a critical component of overall wellness and nutrition does play a key role. "Mental disorders account for the leading cause of disability worldwide, with depression accounting for the large proportion of that burden.”
We are a highly complex and integrated system and lifestyle modifications are incredibly important and there is an emerging interest in nutritional psychiatry. It is an ideal time to focus on nutrition right now, especially as we gear up for solo workouts and virtual races. Since we are missing our usual routines and social interactions, we need to do all we can to make sure our bodies and our minds feel like they are functioning well. An Angus Reid poll recently revealed that about 50% of Canadians feel our mental health has worsened since the pandemic started. Dr. Jonathan Danson is a Clinical Psychologist who believes that COVID-19 and physical distancing are particularly problematic for high achievers. Time commitments are different now and more time can actually cause more anxiety. There are many other factors that can cause mood concerns right now too, of course.You can listen more about this topic on episode 13 of the Eat Move Think podcast with Shaun Francis, Chair and CEO at Medcan.
Mental health is a complex topic and we have to be careful when using food as the only treatment for mood. This article is focused on those experiencing a change in mood related to the recent pandemic or some mild to moderate forms of depression and anxiety. For those with more severe cases of mental health issues, these guidelines are only intended to be as a suggestion along with other forms of treatment like medication, to help you feel better faster, or during certain circumstances when your mood is worsening. I am not an expert on this topic so if you have major concerns about mental health please talk to the appropriate qualified professional.
Watching and hearing negativity from stressful news can cause higher levels of stress. Stressors are things that we experience or observe and feel we are unable to cope with mentally, causing stress reactive areas of our brains to turn on. Stress hormones, like cortisol, then turn on and the impact on our bodies can lead to changes to our physical and mental health. When we are exposed to chronic stress it can be challenging to follow through with healthy behaviours. Stress right now is unavoidable so we need to find coping mechanisms. Since our brains are negatively impacted by chronic stress, this can impact our mood, learning and possibly sleep as well. Acute stress causes less of an interest in food due to the fight or flight response, but chronic stress elevates cortisol levels and people might turn to food for comfort since this can improve our mood due to serotonin release. According to Dr. Yoni Freedhoff “Our job is to live the healthiest lives we can honestly enjoy with the smallest amount of indulgence we need to like our lives. During a pandemic we might need more of an indulgence than usual.” If we are hungry and need comfort we might eat more. But everyone’s response is different and some might not be eating enough. This can happen to some athletes due to exercise’s ability to interfere with hormones that regulate hunger levels. The main point is everyone’s nutrition needs and response to stress are different but there are some commonalities related to how different components in food make different neurotransmitters (chemical messengers) that can change how we feel. Tryptophan is an amino acid that helps make serotonin in the brain. You will already find it in protein-rich foods like chicken, turkey, fish, nuts & seeds, soy, beans/lentils and eggs. Serotonin is a messenger chemical in the brain and improves mood and how we feel. Many anti-depressant medications help the body regulate serotonin. The brain is protected by the blood brain barrier and only the important nutrients can go in and out for protection and not everything makes it across. Research done in 2016 found a way for tryptophan to get access to the brain. Pairing tryptophan-rich foods with antioxidant-rich foods like fruits and vegetables helps to get more tryptophan into the brain. Antioxidants also help protect enzymes involved in this process and reduce inflammatory markers. Getting a wide variety of plant foods is important to get adequate amounts of antioxidants (Read more about antioxidants here). When we don’t eat enough nutrient-rich foods our body may lack vital vitamins and minerals, which can affect brain function, energy levels and mood. Ideally, we want to get the vitamins and minerals our bodies need to thrive from a balanced diet with plenty of fruit and vegetables, but some people may need to take supplements to meet these needs. A few examples include folic acid for pregnancy, vitamin D for everyone in the winter months and iron supplements for people diagnosed with anemia.
Nutritional Psychiatry is a growing field and describes the brain, gut, and mood connection. In the second part of this two part article we will look even closer at the research between diet, gut health and mental health, as well as share our suggestions on improving our energy levels and well-being through our diet. For now, I wish you well and be aware of your stress levels.
Nutritional psychiatry is a growing field and describes the brain, gut, and mood connection. (You can read more about it here). It is well recognized that eating fruit and vegetables can benefit physical health. Newer studies are proposing that it may also benefit psychological well-being. According to a study from the University of Leeds, eating more fruit and vegetables can improve psychological well-being and life satisfaction. Researchers looked at data from over 45,000 people in the UK and found a positive association between the quantity of fruit and vegetables eaten and self-reported mental well-being. The study controlled for other factors that might affect mental well-being such as age, income, education, lifestyle and health, and other foods eaten such as dairy and bread. This study was longitudinal meaning it can relate changes in fruit and vegetable consumption to changes in self-reported well-being for the same individual over time (in this case, 2010-2017). Fruits and vegetables tend to be carbohydrate dense and there is some research to suggest that the positive effects of consumption could be partially related to increased concentrations of serotonin in the brain. This study was observational so it can only draw an association and can’t demonstrate cause and effect. There are so many benefits to encouraging better dietary habits for physical health in the long run, and now we are getting more evidence that it can improve mental well-being and life satisfaction as well, in the short run.
A high performance wellness podcast called “Eat Move Think” by Shaun Francis of Medcan, one of the world’s leading health and well being companies has an episode on how food affects how we think. Dr. Felice Jacka is one of the world-renowned experts on Nutrition Psychiatry and spoke with Shaun on episode 2 to discuss how diet affects our mental health. Leslie Beck is a Registered Dietitian and Medcan’s Director of Food and Nutrition, describes how Nutritional Psychiatry is changing the way we think about mental health from this emerging field. Recognizing that the foods we put in our bodies impact brain function, emotions and moods. Observational research is showing the quality of our diet is linked to some mental health disorders. A trial named the Supporting the Modification of Lifestyle in Lowered Emotional States (SMILES)was done at the Food and Mood Centre at Deakin University in Australia. Sixty-Seven participants with major depression were split into two groups, one who followed the Mediterranean diet plus help from a Registered Dietitian. The second group was a social support group with no diet modifications. After three months, the dietary intervention group had a significant improvement in depression and anxiety symptoms. Dr. Felice Jacka coined the term Nutritional Psychiatry and is a principle investigator in the SMILES trial. It was the first intervention like this and took people with clinical depression and helped them make improvements to their diet, resulting in a profound impact on depression scores. You can read more about the results and trial here.
"The gut is our second brain"
The Mediterranean diet is the most studied dietary pattern with strong accumulated evidence for health benefits (i.e., cardiovascular, cancer, diabetes, dementia and depression). It is a diet that is high in diverse plant foods. Many other diets are also considered to be notably health-positive, like the Norwegian diet, Japanese, and Chinese diets, to name a few. We know what a healthy diet comprises: high in diverse plant foods, quality proteins, and unsaturated fats. It is
proposed that we should strive for a “plant predominate” diet. The gut is our second brain since it has its own nervous system. Microbiotic bacteria in our gut play an incredibly important role in our health as they help us digest dietary fibre. Bacteria break food down through a process of fermentation and release a vast range of metabolites, interacting with every cell in the body and influencing the immune system and brain plasticity. The gut can’t do what it is supposed to do in normal physiological functions without dietary fibre. The ketogenic diet has gained recent popularity and is the opposite of what is healthy for the gut. Read more about research on the link between gut and brain health.
Having long gaps in between meals can also affect energy levels and mood. The term “hangry” combines ‘hungry’ and ‘angry’ and refers to getting short tempered when you haven’t recently eaten. Some who have tried intermittent fasting will know what this feels like and this affects short term mood. The brain needs an adequate supply of energy from blood glucose to concentrate. In fact, the brain uses up 20% of all energy needed by the body! The glucose in our blood comes from all the carbohydrates we eat (fruit, vegetables, whole grains, and lactose in milk products). When we eat breakfast and meals containing some carbohydrates consistently throughout the day (no longer than about 4 hour gaps in between meals/snacks), we have enough glucose in our blood. Running and other forms of exercise will use this for energy along with carbohydrates stored in the form of glycogen in our muscles and liver. Our bodies can only store a certain amount of carbohydrates so once we run out, that is when we start to feel tired, weak and even ‘fuzzy minded.’ This state of low blood sugar (hypoglycemia) will impact how hard we can run, meaning we will need to slow down or sometimes stop all together during long and hard efforts. It will also negatively affect our mood and how we recover.
When runs start to get over 90 – 100 minutes in duration, it is important to consume carbohydrates during activity to ensure good concentration and overall performance. Runs also feel very hard when in a ‘depleted’ state and could further impact mood if someone is already concerned about experiencing mood issues.
A few suggestions for a healthier gut, improved mood and energy levels:
If your body is deficient in some vitamins and minerals it could affect mood, brain function and energy levels.
Simply changing your dietary intake pattern doesn’t completely translate into a cure for mental illness, but what we eat does impact depressive symptoms, our mood and energy levels. Improving your whole diet matters most for benefiting mental health. After all, the building blocks of what our brain is made of is nutrients, so make sure you are fuelling it properly each day we eat, move, think and live!
Rachel Hannah is a Registered Dietitian at the University of Guelph's Health & Performance Centre. Hannah is also an elite runner, Rachel ran her debut marathon in 2:33:30 at the 2015 Ottawa Marathon and has represented Canada at the Cross Country World Championships and the Pan American Games.
For more information about any details of this article or to discuss further ideas please contact Rachel at
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Ocean, N, Howley, P & Ensor, J. (2019) Lettuce be happy: A longitudinal UK study on the relationship between fruit and vegetable consumption and well-being. Social Science & Medicine, 222: 335-345
O’Neil, A, et al., (2013) A randomised, controlled trial of a dietary intervention for adults with major depression (the “SMILES” trial): study protocol. BMC Psychiatry, 13(114).
Strasser, B, Gostner, JM and Fuchs, D. (2016) Mood, food and cognition: role of tryptophan and serotonin. Current Opinion in Clinical Nutrition and Metabolic Care, 19(1):55-61.