From a purely evolutionary perspective, fat has been the primary fuel source responsible for sustaining human life. Since this energy-dense macronutrient supported the growth and development of a more complex brain, fat is literally what made us human. Mastering the use of fire for cooking animal meat greatly reduced the incidence of foodborne illnesses, allowing for its safe and consistent consumption. The high-fat elements of regular meat intake provided an exceptional source of nourishment to the brain, allowing our intellectual capabilities to rise above those of our predominantly vegetarian, great ape cousins.
While carbohydrates provide fast-burning energy, fats are an exceptionally fuel-efficient macronutrient that consistently deliver the slow-burning energy we need for the activities of daily living and/or longer, slower endurance training.
The building of a campfire provides a useful analogy for examining how your body burns fats and carbohydrates differently. In order to create a useful and lasting fire, you need substantial, slow-burning logs. While you might use kindling to get the fire started, it wouldn’t be efficient to build your campfire completely out of twigs and newspaper. You would have to feed the fire constantly in order to keep it going; it would never get very hot and you’d be annoyed by all of the ash (waste) it produced. Carbohydrates are like twigs and newspaper; fats are like slow-burning logs.
In addition to being a longer, slower, and cleaner source of energy, fats provide the building materials necessary for healthy (meaning flexible) cellular membranes. They provide the raw materials for many hormones while helping to regulate the function of many others. They help deliver the fat-soluble vitamins (A, D3, K2, and E) to the places they are needed. And although we can make most of our own fatty acids (from digested fats), dietary fats provide us with the two critically essential ones we can’t make—the alpha linoleic (an omega-3 fat) and the linoleic (an omega-6 fat).
While things are beginning to change, dietary fats are still often regarded as unhealthy. Remember the low-fat craze of the 1980’s and 90’s? Fat—especially saturated fat—was demonized and unfairly blamed for the skyrocketing incidence of chronic illness. We know better now. And what we know is that large amounts of sugar and/or processed carbohydrates are the true health hazard.
Eating more of the right kind of fat can:
• Encourage the burning of excess body fat
• Improve digestion and elimination
• Reduce sugar and carbohydrate cravings
• Improve both physical and mental performance
• Promote healing and recovery
From a scientific standpoint, fats are organic molecules made up of carbon and hydrogen elements joined together in larger groups called hydrocarbons. The arrangement of these hydrocarbon chains determines the fat type. The simplest unit of fat is the fatty acid. Fatty acids are made up of simple hydrocarbon chains that can offer hydrogen atoms an empty space to dock or bond. The more hydrogen atoms bonded to a chain, the more saturated a fat is.
Like dietary carbohydrates, dietary fats also come in different forms, each with their own health-enhancing or health-reducing effects.
Saturated fats (like coconut oil, butter, or palm oil) are easily identified because they are solid or semi-solid at room temperature. Since there are no empty spaces on their chains for other hydrogens to bond, saturated fats are chemically stable. They don’t oxidize or damage easily. It makes sense that foods high in saturated fats thrive in warm climates; they have evolved and adapted to being more impervious to the damaging effects of heat.
Keep in mind that this type of saturation is naturally occurring and very unlike that found in artificially saturated hydrogenated or trans fats. These faux fats are created when hydrogen ions are forced onto the available bonding sites of an unsaturated (liquid at room temperature) fat until it becomes solid. This industrial process is known as hydrogenation. And it’s done in the interest of maximizing a product’s profitability (hydrogenated oils are a cheap ingredient to use) and prolonging its shelf life at the expense of your health. Since trans fats have an abnormally rigid structure, the body can’t process them like a natural fat. Research has shown that just one meal with a high trans-fat content can negatively affect vascular function and blood vessel elasticity.
When three fatty acids are joined together, they form a triglyceride. Triglycerides are the most common type of fat found in the diet and the major storage form of fat found in the body. The body breaks down triglycerides into fatty acids and glycerol which are both re-packaged in various ways before they are sent to their target destinations. Since it takes time to breakdown and transport fat, it takes several hours for dietary fat to enter the bloodstream.
If only some hydrogens have bonded to a given chain, the resulting fat is unsaturated. One of the least-saturated fats are the omega-3’s. Anthropological research suggests that our hunter-gatherer ancestors (who did not suffer from any form of inflammatory disease) consumed omega-6 and omega-3 fats in a ratio of roughly 1:1. Today, the ratio found in a typical American diet is somewhere between 10 and 30:1. When you consider that corn oil (prevalent in processed foods) has a ratio of 46:1, it’s not that difficult to understand why fatty acid imbalances and chronic, inflammatory diseases have become so common. Since many athletes are constantly battling the effects of chronic inflammation (an unavoidable consequence of high-volume training), particular attention should be given to keeping their omega-6 consumption in check.
The take home point is that there are bad fats (those that cause degenerative disease) and good fats (those we need for optimum health and performance). This doesn’t mean we can eat even the healthiest of fats in an unlimited amount; they are energy dense and we still need to achieve the correct energy balance. But healthy fats can and should be eaten regularly for optimal health, performance, and recovery. It may require a 180-degree shift in thinking, but the next time you eat a bagel with cream cheese, remember that the cream cheese is actually the most nourishing part.
In general, good fats are high in omega-3 fatty acids and include the monounsaturated found in nuts, avocados, coconut products and olive oil; the polyunsaturated found primarily in fish; and the saturated from grass-fed meat and dairy products. Among many things, omega-3’s help to reduce inflammation. They act as a natural blood thinner and they promote optimal brain function. Unlike saturated fats, those high in omega 3’s are very flexible which allows them to be easily converted into hormone-like molecules and readily incorporated into cellular membranes. The downside of this flexibility is that they are very susceptible to being damaged by heat and light. Unlike the heat-hardy saturated fats, the omega 3 fats which include cold-water fish (such as salmon and sardines) and seeds (like flax and chia) are the product of colder environments.
Bad fats are those that contain a disproportionately large amount of omega 6 fatty acids; they are typically sourced from plants (especially corn, soy, and canola), and are easily damaged by heat. While we need some omega-6 fats (especially for the formation of a bioactive fat called gamma linolenic acid (GLA)) that promotes youthful skin, a normal menstrual cycle, and a healthy metabolism), an excessive omega-6 fat intake leads to the onset of high blood pressure, heart disease, cancer, and diabetes—the inflammatory diseases du jour.
Given what you now know, you may be questioning the American Heart Association’s recommendation that adults limit their daily intake of calories from saturated fats to no more than five percent. They urge the use of vegetable oils instead. Unfortunately, this misguided dietary advice to swap omega 6 for omega 3 fats has contributed to the prevalence of chronic disease, and to poor daily performance and recovery.