Nutrition and Mental Health Part 9 - Studies about diet and mental health correlation

Let's learn about our food choices and how can we modulate our own brain responses. For this, we need to check the research made about diet and mental health, how we assess dietary patterns, and how to observe the relationship between what we eat and how we feel.

In order to research dietary patterns, most researchers used food frequency questionnaires (FFQ), to track what a person eats over a certain period of time. Those questionnaires are given to thousands of people belonging to one community, and this action is called a large population epidemiologic study. This way the researchers have the information necessary to check participants' food habits and to identify if there is a connection between the food consumed and the measured healthy behaviors. This is an association or correlational study.

Food frequency questionnaires are very detailed, lasting up to one year, asking questions like how frequently do you eat broccoli and kiwi, or if you drink coffee three times a day, what do you put in it? Milk, sugar, sweetener, and how much? Do you eat avocado daily, weekly or monthly? Then the researchers work with the data provided to see if certain foods are grouped together. Does Sunday chicken roast get eaten together with roasted potatoes and Yorkshire pudding? People drinking fizzy drinks also eat chocolate? And so on. When you do this, a pattern starts to emerge, and they are labeled as traditional diet, Western diet, or English diet. After this is done, you can correlate the dietary habits with other health outcomes like exercise, mental health, or smoking.

(example of FFQ)

Let's start with the studies researching how a good diet and a bad diet influence our mental health. We know that poor diet precedes the onset of mental health problems. More than that, improving your diet can improve your mental health. Using a food survey or a food frequency questionnaire, you can find some food habits, for example, you always have the same breakfast every day except Sunday, or you eat the same dinner every Friday evening. You can do this for a month, or even better, for six months, and then you can find correlations, some of them quite wild, like for example how the divorce rate is strongly correlated with the consumption of margarine (this one is in fact quite easy, as people who chose to buy margarine instead of butter are most of the time poor, and lack of money tends to increase the change of divorce). After that, the hard part, you need to see if you can prove there is causality or not. Studies were made comparing healthy diet and unhealthy diet, Mediterranean versus western diet, and one consistent result was that the food quality matters a lot. As my grandad used to say "Never buy a cheap bed, cheap shoes, or cheap food". Self-explanatory, as sleep, diet, and walking are essential for our health.

So what I want you to do now implies a bit of work, but the benefits are so great, that they can add years, if not decades, to your healthy life. You need to buy a notebook and write all that you eat, at the end of every day, for at least a month. And then, you need to study your diet, find patterns, identify unhealthy habits, and try to improve (the easiest way to do that, in my opinion, is to reduce the bad habit at half, while you build a good habit, for example, if you drink four glasses of Coke every day, start by drinking 1 glass of Coke, one of water, one of Coke, one of water).

Next time we will try to delve even deeper into the correlation between diet and mental health.

Have a perfect day, see you tomorrow,
George