Did you know DNA affects your fat sensitivity?
Genetics of fat sensitivity: FABP2, saturated fats, obesity and the risk of a heart attack
Fats have had a bad rap for years. They have taken the brunt of the blame for the rise in obesity, what is now considered a public health crisis. In our haste to eliminate fats from our diet, we forget the need to control the quantity of what we consume, and often fats are replaced with refined carbohydrates. As if curbing the cravings for deep-fried food wasn’t hard enough already, our genes also play a role in making some of us much more prone to gaining weight than others, especially when we eat fatty foods. FABP2 is one such gene. It controls just how much fat you will absorb from your diet, and stored in all those places you don’t want it.
Our bodies need fat for energy, to absorb vitamins, for blood clotting and for inflammation. They surround our nerves, and make the vital membrane that protects our cells. But not all fats are equal. The polyunsaturated fatty acids, omega-3 and omega-6, that we get from fish are ‘healthy’ fats. These fats protect us from things like heart attacks, obesity and even Alzheimer’s disease.
Trans fats, on the other hand, are ‘bad’ fats. They are a byproduct of a process called hydrogenation. This process turns healthy oils (e.g. vegetable oil) into a solid to extend shelf life. The food industry is nothing but innovative, so food makers have found ways to include trans fats in many of our foods. Often listed as “partially hydrogenated oil” on labels, they are everywhere from cookies to fries. However, it is now obvious that trans fats offer no health benefits, and instead increase the risk of heart disease, strokes, diabetes and many other adverse conditions.
In the middle of these good and bad fats, are the saturated fats found in red meat, coconut oil, and dairy products. The jury is still out on whether these in-between fats are good or bad for us. However, it is well established that a diet high in saturated fats drives up LDL-cholesterol levels, increasing the risk of cardiovascular disease.
It’s a pity that we can’t choose the genes we inherit the way we can control our diet. If you could, you would definitely choose a specific version of the FABP2 gene. This gene gives instructions to make a fatty acid binding protein. This protein is found in the gut and is responsible for fatty acid absorption. The activity of this binding protein can vary from person to person due to genetic variation. Genetic variation refers to small DNA changes that exist between people. One variant known as rs1799883 or FABP2 A54T makes a protein with an enhanced ability to transport both saturated and unsaturated fats.
The increased absorption of healthy unsaturated fats appears to have little health impact. However, individuals with one or two altered copies of the FABP2 gene are more likely to have high levels of saturated fats in their blood, as well as elevated LDL-cholesterol. Both of these are risk factors for obesity, cardiovascular disease, insulin resistance and type 2 diabetes.
Many dieticians recommend consuming less than 10% of your calories per day in the form of saturated fats. The American Heart Association recommends even less, stating that adults should consume 20-35% of their daily calories from fat, with less than 7% in the saturated form. If you have the rs1799883 FABP2 variant and want to stay healthy, less than 5% of your daily calorie intake should be from saturated fats. A simple genetic test can help you understand your health risks associated with saturated fat intake.