Can a SAD diet actually make you feel sad?

Studies show that depression and diet may be related.

Several studies have found that people who ate a poor-quality diet — one that was high in processed meat, chocolates, sweet desserts, fried food, refined cereals and high-fat dairy products — were more likely to report symptoms of depression. The good news is that the people who ate a diet rich in fruits, vegetables and fish were less likely to report being depressed.

Which comes first? Poor diet or depression?

One could argue that, well, being depressed makes us more likely to eat unhealthy foods. This is true, so we should ask what came first, the diet or the depression? Researchers have addressed this question, thankfully. A large analysis looked only at prospective studies, meaning, they looked at baseline diet and then calculated the risk of study volunteers going on to develop depression. Researchers found that a healthy diet (the Mediterranean diet as an example) was associated with a significantly lower risk of developing depressive symptoms.

The bottom line : Good Food = Good Mood

A dietary pattern characterized by a high consumption of red and/or processed meat, refined grains, sweets, high-fat dairy products, butter, potatoes and high-fat gravy, and low intakes of fruits and vegetables is associated with an increased risk of depression.

The gist of it is, eat plants, and lots of them, including fruits and veggies, whole grains (in unprocessed form, ideally), seeds and nuts, with some lean proteins like fish and yogurt. Avoid things made with added sugars or flours (like breads, baked goods, cereals, and pastas), and minimize animal fats, processed meats (sorry, bacon), and butter. Occasional intake of these “bad” foods is probably fine; remember, everything in moderation. And, for those who are trying to lose weight, you can’t go wrong with colourful fruits and veggies. No one got fat eating berries or broccoli. Quality matters over quantity. And when it comes to what we eat, quality really, really matters.

Resources

Dietary patterns and depression risk: A meta-analysis. Psychiatry Research, July 2017.

Diet quality and depression risk: A systematic review and dose-response meta-analysis of prospective studies. Journal of Affective Disorders, January 15, 2018.