Ever have that sinking feeling? Well, with the darker months of winter fast approaching we can all feel a little depressed about this time of year. How about fixing that by fixing our diet? A new study asked what foods appear to make us more depressed and why and they came up with some fascinating results.

The 2013 Harvard study published in the journal Brain, Behavior, and Immunity compared the eating habits from food frequency questionnaires (FFQs) of 43,685 depression-free participants (aged 50 to 77 years) as part of the Nurse’s Health Study. These participants were monitored for 12 years between 1996 and 2008 during which 2,594 documented cases of depression were identified. In addition, the researchers also established an inflammatory dietary pattern (IDP) score based on the effects of various foods on the plasma levels of the following three classic biomarkers for inflammation: C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor a (TNF-a) receptor 2.

Once established, this score was calculated for the study participants. Analysis of the data revealed that those in the top 20% of IDP scores (i.e., those with the greatest inflammation status) showed a 41% increased risk of depression compared to those in the bottom 20% of IDP scores. Since they knew what foods caused these changes in IDP scores the authors were able to assign types of foods to higher or lower IDP scores. It appears green leafy vegetables (spinach, lettuces etc.), yellow/orange vegetables (carrots, yellow squash, sweet potatoes), wine, coffee and olive oil were all associated with low IDP scores. Sugar-sweetened soft drinks, diet soft drinks, refined grains (e.g., white bread, bagels or muffins, white rice, pasta and pancakes or waffles), red meat and margarine were associated with high IDP scores. So, a poor diet gives you a higher IDP score which in turn is associated with a higher risk for depression. Also, the researchers found a dose-response relationship between IDP scores and depression risk which means that if your diet gets any worse you’re even more likely to be depressed.

So, put a smile on your face this winter by loading up on delicious fruits and vegetables and lay off the red meat, sugary drinks and refined grains if you want to avoid diet-induced chronic inflammation. Other great ways to avoid depression are practicing yoga, eating foods containing zinc and, this may be challenging, try avoiding  comfort foods as research suggests they really aren’t comforting in the long run!

Published November 1, 2013