According to the researchers, people who eat more trans fats from cheese, milk or processed foods (making up more than 0.6 percent of total calorie intake) may have a 48 percent increased risk of depression, compared with those who consume almost no trans fats.
On the other hand, 'good' polyunsaturated found in fish and vegetable oils, and olive oil has a protective effect against depression, the researchers found: "We discovered that this type of healthier fats, together with olive oil, are associated with a lower risk of suffering depression."
Considering that depression cases are on the rise, with some 150 million people are affected by this disease worldwide, this finding is noteworthy.
This is due to "radical changes in the sources of fats consumed in Western diets, where we have substituted certain types of beneficial fats -- polyunsaturated and monounsaturated in nuts, vegetable oils and fish -- for the saturated and trans-fats found in meats, butter and other products such as mass-produced pastries and fast food," says lead author Almudena Sánchez-Villegas of the rising trend of the diease.
Previous research has already linked trans fat (which are created through a process that adds hydrogen to oil) to increased heart disease risk, but this is the first study to analyze the effects of dietary fat on depression.
It's believed that depression may be related to low-grade inflammation. And because trans fats increase inflammation (also a risk factor for cardiovascular disease, raised bad cholesterol and lowered good cholesterol), this could potentially increase depression risk.
The good news is that you can easily ban trans fat from your diet by paying a little more attention to what you eat:
- Cut back on your consumption of margarines, commercially-baked and deep-fried foods and products including pastries, cakes, crackers, cookies and biscuits.
- Buy fresh produce as such fruits, vegetables and lean meat over processed foods.
- Read food labels: Look out for words such as "vegetable shortening", "hydrogenated oils" or "partially hydrogenated oils" -- these ingredients mean that the food contains trans fat.
