Fat. The long ridiculed black sheep of the three macronutrients, with the other two being carbohydrates and protein. Fats are one of the more controversial health and nutrition topics of recent history. This nutrient, which comes in three forms: saturated, unsaturated, and trans, has been commonly associated with such problems as weight gain, heart disease, high cholesterol, and the break up of Ross and Rachel (okay maybe not that last one). However, recently fats have made a triumphant return to notoriety by such diet protocols as the Atkins plan, South Beach diet, Paleo, and ketogenic diet. There is much to discuss about the dietary role of fats, good fats and bad fats, and how to go about finding good sources of fat for your diet.
Fats serve six primary purposes in the body:
1. Fats comprise the structure of the membranes of our cells.
Said another way, fats are the barriers that provide protection for the cells of our bodies! This is no small job, as the human body contains trillions and trillions of cells.
2. Fats regulate hormone production and function.
For example, consumption of dietary fat is associated with sex hormone production (estrogren, androgren, and testosterone).
3. Dietary fats play a large role in maintaining the brain and central nervous system.
Fatty acids from the food we eat help nerve signaling and blood flow to and from our noggins.
4. Fat is necessary for vitamins A, D, E, and K.
These vitamins serve a host of functions in the body such as enhancing immune system functioning, red blood cell development, cellular function, and blood clotting. Without adequate dietary fats, none of these crucial vitamins will be digested, and without digestion they will not be available to function in our bodies.
5. Dietary fats provide essential fatty acids, omega-3 and omega-6.
This is arguably the most popularly discussed function of dietary fats. The human body is incapable of synthesizing omega-3 and omega-6 fatty acids on its own. These fatty acids do a lot of good in the body, and these benefits will be detailed later.
6. Dietary fat provides energy.
One gram of fat provides more than twice the calories of both protein and carbohydrates.
For those of you who are more visual learners, here is a concise infographic detailing the information above:
Also, one benefit to fat that doesn’t serve a purpose physiologically but certainly deserves mention when discussing any sort of diet is that fat is a flavor enhancer! Foods that are higher in fat are generally more flavorful and have a pleasing texture. Now that we’ve covered the importance of fats, let’s talk about the good, the bad, and the ugly of how they are ingested with the food we eat.
Let’s start off with the good! Otherwise known as “healthy fats,” these fats are made up of the omega fats (3 and 6), as well as the monounsaturated fats. The term, “healthy fats,” was bestowed upon this group because of the beneficial effects on blood flow, blood vessels, inflammation, as well as metabolism of the body. Further, the essential fats, omega-3 and -6, play major roles in the body, and serve to balance one another.
For example, omega-6’s contribute to the body’s ability to clot the blood, feel pain, constrict blood vessels, and produce inflammation. While these things all sound unpleasant on their own, they are crucial functions for health, as the body has to do all of these processes in order to protect itself. Further, the omega-3s, which are highly popular marketing tools, serve to maintain cell fluidity, which serves the bodies nervous system function, as well as decrease pain, inflammation, airway constriction, and blood vessel constriction. So why not just eat nothing but the lovely sounding Omega-3s, you say? Because, as with most things in the body, you need balance, and this is where we begin to see some of The Bad of dietary fat.
More often than not, fat intake is out of balance, as is the case in the previously discussed Omega-6 vs. Omega-3s of the modern American diet. Omega-6 oils, such as corn, safflower, and rapseed oil, are rampant in the processed foods we buy in grocery stores. Additionally, meats from animals that are feed a largely corn based diet also will be higher in the Omega-6 fatty acids. What has happened is that the average American diet has become saturated (hehe…fat puns) with Omega-6s, leading to increased inflammation, poor blood circulation and airway function. This is largely due to the fact that many Americans will eat cheap meats, but not incorporate high Omega-3 foods such as things like fish, walnuts, and flaxseed into their diets.
This imbalance problem can also be seen between the saturated and unsaturated fats in the American diet. Excessive intake of saturated fats (i.e. butter, margarine, shortening, meats, etc.) is associated with health issues such as various cancers, Alzheimer’s disease, and heart disease. HOWEVER, when consumed in a balanced diet, which includes adequate unsaturated fats (nuts, plant oils, fish, avocado), the issues surrounding saturated fat tend to decrease dramatically. Further, it is hard to determine whether or not saturated fat consumption on its own is responsible for the associated health problems or if there is contribution from other poor health choices, such as elevated consumption of sugar, lack of exercise and sleep, and increased consumption of processed foods. So for now, aim for balance of fats and “The Bad” of dietary fat will quickly return to being “The Good!”
Now it’s time to discuss The Ugly of fat. Trans Fats. Trans Fats are fats that have been chemically altered in a lab and they are all sorts of unhealthy for you. Why even include them in food, you ask? The answer unfortunately is profit. The process of creating a trans fat is to utilize relatively inexpensive oil, chemically alter it, and add it to food in order to greatly increase the food’s shelf life. Further, the texture of the foods containing trans fats is often very pleasurable. As a result, foods that would have, and should have gone bad long ago, can remain in the store waiting to be purchased, thus saving the producers money on unsold food items.
While shelf life might sound good, the possible side effects of increased trans fat consumption do not. Because of their chemically unfamiliar nature, and structure, trans fats aren’t digested properly or fully in the body, leaving them to block arteries and decrease cell fluidity. As a result, trans fat consumption has been linked to such severe health problems as coronary heart disease, cancer, increased cholesterol, Alzheimer’s disease, and other chronic disease. In fact, one large-scale study of over 80,000 women found that the highest correlate of heart disease was trans fat consumption. Avoid any food with an ingredient that lists “hydrogenated,” or, “partially hydrogenated” on it’s label.
The morale of this very long story about fat, is that naturally occurring fats are NOT bad for you when consumed in a whole food, balanced way. Fats are not only necessary for optimal functioning, but can provide many wonderful benefits. Fats play a role in increasing brain function, sexual function, blood flow, and immune response when consumed properly, and as a result they should not be neglected. The following table details of some good sources of different types of fats. Enjoy!
Final note: The jury is still relatively out on dairy, and it’s typically a case by case basis for whether or not it is a beneficial part of a healthful diet. For the most part, the issues surrounding dairy center on whether or not it is an allergen, and cause of inflammation in the gut. So for now, if you can consume dairy and feel good afterwards then it deserves a place in your refrigerator!