Fats are vital to a healthy . Fats help carry, absorb, and store the fat-soluble vitamins (A, D, E, and K) in your bloodstream. Fats also help regulate your body temperature. Having some body fat cushions your organs and protects them from injury. However, as your probably already know, there are good fats and bad fats for your body . . . and your brain.

The good fats, or lipids, that work so beautifully in your body-and your brain-are called fatty acids. Essential fatty acids cannot be manufactured in your body so must come from the foods you eat (or supplements you take, although food sourcing is highly preferable). As far as your body, fatty acids are primarily used to produce -like substances that regulate a wide range of functions, including blood pressure, blood clotting, blood lipid levels, the immune response, and the inflammation response to injury or infection.

Approximately 60 percent of your brain matter consists of fats that create all the cell membranes in your body. Let's review: The good fat in your brain matter creates all the cell membranes in your body! If your diet is loaded with bad fats, your brain can only make low-quality nerve cell membranes that don't function well; if your diet provides the essential, good fats, your brain cells can manufacture higher-quality nerve cell membranes and influence positively your nerve cells' ability to function at their peak capacity. (Magnesium also plays a critical role in nerve cell development and optimal functioning.)

Thus, it's important to choose foods that offer the essential fatty acids your body and brain need. Unfortunately, even good fats are a very concentrated source of energy, providing more than double the amount of calories in one gram of carbohydrate or protein, which is why it's important to choose the healthy fats and to eat them in moderation.

Omega-3 Fatty Acids Are Good for Your Brain

Omega-3 fatty acids are great for mental clarity, , and focus. They play an essential role throughout your life and should be at the top of your shopping list in terms of positive value for your brain. However, they are fattening so maximizing the sources in terms of benefits as opposed to caloric content is a wise move. Certain foods containing omega-3 fatty acids are especially good for your brain. These include:

Certain cold-water fish (bluefish, herring, mackerel, rainbow trout, salmon, sardines, tuna, and whitefish)

Olive oil

Flaxseed oil

Peanut oil

Canola oil

Studies have revealed that Omega-3 fatty acids, which are essential for maintaining normal cognitive function, have additional advantages in the brain. For example, DHA and EPA, the Omega-3 fatty acids found in fish, particularly salmon, albacore tuna, sardines, and swordfish, are vital for a sharp mind.

They're Good for Your Heart

Omega-3 fatty acids may also decrease the risk of stroke and heart attack, as well as protect against abnormal heart rhythms, the leading cause of death after heart attacks. Omega-3 fatty acids may provide protection by enhancing the stability of the heart cells and increasing their resistance to becoming overexcited. Eating fish just one to two times per week has shown a 40 percent reduction in sudden deaths from cardiac arrhythmias.

They May Tamp Down

Researchers at Harvard University suggest that omega-3 fats (which are also available in supplements, though food sources are preferred) may disrupt the brain signals that trigger the characteristic mood swings seen with . If these findings hold true in future studies, omega-3 fatty acids may have implications for successfully treating other disorders such as and . Caution: No one with these disorders should attempt to self-medicate. Always consult with your doctors before adding supplements.

Limit Saturated and Hydrogenated Fats

Essential fatty acids are the most important nutrients for your brain, but most American diets are sadly lacking in these "good" essential fats (found in flaxseed oil, olive oil, and ) and way over the top when it comes to saturated, hydrogenated, and partially hydrogenated trans fats. You can easily recognize the "bad" fats (saturated and processed fats), as they're the ones that have been processed or hydrogenated and remain solid when refrigerated. They are typically found in:

Commercial baked goods: pies, cakes, doughnuts, cookies, etc.

Processed foods and fast foods

Fatty cuts of beef, pork, and lamb

Butter, margarines

Whole milk, ice cream

Cheese

Crackers, potato chips, corn chips, cheese puffs, pretzels, etc.

Candy

Mayonnaise and some salad dressings

Palm, palm kernel, and coconut oils

When unsaturated fats are heated for a long time, in metal pots and pans, they form altered or trans fatty acids. In contrast to healthy fatty acids (whose soft pliability helps nerve cell membranes function smoothly), these trans fatty acids become double-bonded, rigid, and thus tend to gum up synaptic or electrical nerve cell communication. Besides greatly increasing your chance of gaining too much weight on foods that contain little to zero nutritional value, here's a short list of the damage trans fats can do to your brain:

Alter the synthesis of neurotransmitters, such as .

Increase LDL (bad) cholesterol and decrease HDL (good) cholesterol.

Increase the amount of plaque in blood vessels and increase the possibility of blood clots forming, both of which puts your heart-and your brain-at risk.

Increase the amount of triglycerides in your system, which slows down the amount of oxygen going to your brain, and the excess of which has been linked to depression.

One reason America has become a nation of overweight people is that our consumption of essential fatty acids has declined by more than 80 percent while our consumption of trans fats has skyrocketed more than 2,500 percent! If you want your brain to be healthy and happy, severely limit saturated and hydrogenated fats.

Two More, Huge Reasons to Ban Trans Fats

Trans fats may be even more harmful than saturated and hydrogenated fats. Saturated fats tend to raise cholesterol levels and thus endanger your heart and your brain, but trans fats can be far worse. Here are two reasons you may want to ban trans fats from your diet:

Trans fat works against your brain by disrupting the production of energy in the mitochondria (the energy factories) of brain cells. When your diet is high in trans fatty acids and low in omega-3 fatty acids, your brain absorbs twice as many trans fatty acids.

When it comes to trans fats, just say no!

This article was co-written by Susan Reynolds and Teresa Aubele, Ph.D.