Research suggests we reach for low-fat dairy to lessen depression

Science says checking your foods can help manage your moods.
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Here's something you may have heard before: food is medicine. The preventative benefits of proper nutrition (eating the right things, while avoiding the wrong ones) cannot be overstated. So, allow me to be annoying for the sake of your health and repeat something. FOOD IS MEDICINE. And it's true for physical as much as mental health.

Making a choice to eat an all-dressed pizza versus a grilled chicken breast over leafy greens for lunch has a much larger impact on your mental health than most people (even some doctors) realize. And I'm not just referring to post-lunch lethargy. Serious mental illnesses have sometimes been shown to improve or abate when appropriate dietary changes are made. Side note: if you're anxious — cut out cigarettes, caffeine and alcohol, yesterday. Medical science is relatively new and constantly evolving (consider that bloodletting was common up to the 19th century and homosexuality was still listed in the DSM as a mental illness as recently as 1987). Nutritional science too is just coming into its own. There are surprisingly few preventative nutrition classes in med school (though again, that is changing, slowly).

Thankfully the science of nutrition keeps getting funding. Recently, researchers in Japan and China have found a correlation between those who consume low-fat dairy and their likelihood of having depression. That likelihood, it seems, is significantly lower.

There is no shortage of documentation highlighting the ills of dairy. In fact, it has a place in the treatment triumvirate of milk, wheat and soy as a potential trigger that can exacerbate general well-being (vegetable oil is also often mentioned in this context). But Professor Ryoichi Nagatomi of Tohoku University and his colleagues in Japan and China are the first to study the different components of dairy and their link to depression. In particular, dairy's fattiness. Research showed that minding dairy's fattiness may be more crucial to our well-being than cutting it out altogether. Your choices in the dairy aisle may be about to waver.   

Ultimately, out of the nearly 1200 people Nagatomi studied (men and women between the ages of 19 and 83), depressive symptoms like "exhaustion, sadness, anxiety, helplessness and hopelessness" were far less prevalent in subjects who consumed low-fat dairy between one and four times a week. The fat content of the products consumed was a major differentiator. What's more notable is that even when the age, sex, health, other nutritional choices and lifestyle of the subjects was factored in, the correlation between low-fat dairy and mood still held true. The low-fat dairy group were simply less depressed across all demographics. Maybe make some room on your fridge door for a quart of skim.

The study is careful to point out that whole-fat milk actually didn't have an impact on depressive symptoms. While this seems counterintuitive, Nagatomi and his team theorize that the depression causing trans-fatty acids in whole fat milk (trans-fats cause inflammation which is terrible for a whole host of ailments) got "cancelled out" by milk's mood boosting hero, tryptophan. Tryptophan is an anti-inflammatory that has a calming effect on one's mood. So, milk is not all bad. But reaching for the low-fat variety may still be advisable.  

More research into the nutritional impact of dairy and its effects on mental health is needed and Nagatomi admits as much. For example, beloved food items like cheese and butter were not used in the study on the off chance that gives your tastebuds some hope.  

The takeaway here is that it may not be necessary to do away with dairy altogether, or any other food group, but experimenting with diet and mood is not an awful idea if you're prone to depressive symptoms. The trick with nutrition is eating right for you. If a far better version of you is one dairy creamer away, it may be worth going without.

If you're struggling with mental health right now, I'm not saying you're sick because you simply aren't eating properly. Mental illness is serious and speaking to health care practitioners and seeking treatment is a crucial, non-negotiable part of getting well. But experimenting with the removal of potential dietary triggers like dairy, gluten, soy (or any other potential culprits) could prove beneficial (it has for many). Nothing is a cure-all when it comes to serious health conditions but every avenue towards wellness is worth exploring. Remember you have the power to do your own research too. Something to think about before tucking into a bowl of rocky road or ordering a poutine with double the curd cheese. In fact, it's something to think about after too. Check your moods and your foods.    


Marc Beaulieu is a writer, producer and host of the live Q&A show guyQ LIVE @AskMen