"Lettuce Be Happy": The Link Between Food and Mood

By Adele Bergin, ARV Mental Health Clinician/Consultant

Not feeling on top of your game? Here’s a tip: consider your diet. 

As a psychologist, when I talk to someone who has been feeling stressed, anxious, depressed, or just not their best self, one of my first pieces of advice is to bring things back to basics. When things seem out of control –whether it is work, family or relationship issues, or current events – it is important to focus on what we can have control over, and that we know is good for our health. This includes our:

• Diet,
• Sleep, and
• Levels of physical activity.

A healthy diet, good quality sleep and regular physical activity are not only the foundation for good physical health, but can also affect our energy levels, our decision making and problem solving ability, and how we feel. When you focus on improving these things, you are going to give yourself the best chance of feeling better. 

What’s the Deal with Diet?

There is significant research showing a link between diet and wellbeing.

A recent study published in The BMJ called “Food and Mood: How do Diet and Nutrition Affect Mental Wellbeing” found healthy eating patterns, such as the Mediterranean diet, are associated with better mental health than “unhealthy” eating patterns such as the Western diet (i.e., high amounts of processed foods, red meat, high-fat dairy products, high-sugar foods, and pre-packaged foods). 

		The Mediterranean diet includes green leafy vegetables, fruits, nuts, legumes, olive oil, cereals, fish and low dietary intakes of meat products and dairy – and is associated with a reduced risk of depression and better mental health (Ventriglio et al., 2020).
In particular, greater consumption of fish, fruit, and vegetables has been shown to reduce the risk of depression and anxiety (Li et al., 2016; Nguyen et al., 2017).

How Might Diet Influence Mental Health? 

We don’t know exactly. But researchers have a few ideas:

One hypothesis is that diets containing high amounts of refined carbohydrates and sugars may increase the risk of depression and anxiety through rapid increases and decreases in blood glucose. Another proposal is that nutritional foods may benefit mental health due to their anti-inflammatory properties (e.g., omega-3 fats in fish). Other studies with rats suggest that gut microbiome may play a role in regulating our emotions. More research is needed, however, to understand how different foods may influence wellbeing. 

But I’m Feeling Blue – I Don’t Want to Eat Nuts and Beans?

If you are feeling stressed, anxious, or depressed, maintaining a healthy diet can be hard. A change in appetite is one of the key symptoms of depression, and an associated lack of energy and interest in activities may reduce your motivation to prepare or enjoy meals. Similarly, anxiety and stress can cause nausea and abdominal issues, which can make eating difficult. 

It is important, however, to try to eat regularly and maintain a balanced diet during difficult times, taking it one small step at a time. 

I Want to Improve My Diet – What Should I do? 

1) Start with a Small, Attainable Goal

If you want to improve your diet, consider starting small. Smaller changes are easier to stick to. Think of one new healthy habit you may want to start.  For example:

• Drink more water
• Eat more fruit / fish / green vegetables / nuts
• Reduce your sugar intake
• Eat more vegetarian meals
• Limit late night snacking

2) Try Habit Stacking

When it comes to improving your diet, it might help to think about it like building new healthy habits. The best way to build a new habit is to identify a habit you already do each day in your daily routine (e.g., wake up, make coffee, eat dinner), and then stack your new habit on top. This is called habit stacking. It is about anchoring your new behaviour to a cue or anchor. People who are successful at adopting new behaviours tie them to something they are already doing. 

The formula is: After/Before [CURRENT HABIT], I will [NEW HABIT]

For example, if your goal is to drink more water, your new habit might be:

 After I wake up each morning, I will drink the glass of water on my nightstand. 

OR

Before I have my first coffee, I will drink a glass of water 

Or:

After I finish a meeting, I will get up from my desk and get a glass of water.

Incorporating one, tiny new habit, into your day is already leading to a healthier you 😊

Other examples of healthy habit stacks might be:

• After I finish dinner each night, I will put a piece of fruit into my work bag for the next day.
• After I feel a sugar craving in the afternoon, I will eat a handful of nuts.
• Before I serve myself meat on my dinner plate, I will put veggies on my plate first.
• After I finish dinner and if I feel hungry again, I will have a herbal tea. 
• After I am stuck in a line, I will look up healthy vegetarian recipes and book mark the ingredients I need.
• After I pick up a new item at the grocery store, I will check the nutrition label.
• After I eat breakfast on Sunday morning, I will plan my meals for the week ahead. 

Ultimately, you may want to work towards a SMART goal. E.g., it might be to drink the recommended 8 glasses of water per day; or eat fish twice per week; or a handful of nuts each day. Whatever your goal is, the idea is to pick one tiny habit to start, practice that behaviour until it is engrained, and then repeat the process with a new tiny habit. 

Starting with smaller habits can gradually create bigger lifestyle changes. 

3) Reward Yourself!

There’s nothing like a pat on the back to keep you headed in the right direction. Making plans to celebrate new habit milestones can help ensure those behaviours stick. Try not to use food-related rewards. Instead, plan activities you enjoy, like getting a massage or buying those new running shoes you want.

Don’t forget that, in the end, your new habits are a celebration on their own. Every effort you make to enact positive change in your life propels you towards a long-lasting healthier future - so give yourself a mental high-five each time you check that new habit off your daily to-do list!

Learn More

If you want to learn more about building tiny habits, check out these authors: 

• B. J. Fogg. (2021). Tiny Habits: The Small Changes that Change Everything. 
• J. Clear. (2018). Atomic Habits: An Easy & Proven Way to Build Good Habits and Break Bad Ones. 

**Please note, the causes of mental health problems are many and varied, and may present independently of a person’s diet. Please remember that help is always available. You can find support here**