Fat gets a bad rap. We work hard to burn it off our bodies, keep it off and rid our diets of it. Regardless of this social stigma, fat is an essential nutrient that is vitally important to a healthy lifestyle.
True, there is an important distinction between healthy and unhealthy fats. Still, the very word “fat” remains a vulgarity in fitness circles. Understanding exactly why we need fat and what sort of fat we should be taking in will help restore this misunderstood nutrient to a healthy place in your diet.
What Fat Does
Primarily, fat is a source of fuel (calories) along with proteins and carbohydrates. Fat, though, provides 9 calories per gram while protein and carbs only offer 4 calories per gram, making fat a much richer source of biological fuel.
Carbohydrates are burned for fuel first during exercise but your body doesn’t store many carbs and typically runs out after about 20 minutes of activity, at which point it begins to use fat. For prolonged exercise, there needs to be fat present in your body.
But fat does a lot more than just keep you moving. Dietary fats carry linoleic and linolenic acids, which cannot be made by your body and must come from your food. These essential acids control inflammation, blood clotting and contribute to healthy brain development. Fat is also necessary for the proper absorption and movement of the vitamins A, D, E and K, all of which keep your hair and skin healthy.
Of course, the form of fat that gets the most attention and causes the most grief is the form that gets deposited around our bodies. This is the body’s method for storing excess calories from all sources, whether it be protein, carbs or dietary fat. This means that dietary fat isn’t solely to blame for fat deposits.
Remember, too, that this is where that fuel comes from when you’ve exhausted your carbohydrate supplies. The trick, then, is eating the right amount of calories to fuel your goals and focusing on the right types of fat.
Good Fat vs Bad Fat
There are two types of fat: saturated and unsaturated. These two types can be divided down even further.
Unsaturated fats are the celebrated “good” fats, and include poly- and mono-unsaturated fats. Both of these fats may help to improve overall heart health by lowering your cholesterol and slowing the formation of plaque on the walls of your arteries. Olives, nuts and fish are all excellent sources of these good fats, including omega-3 fatty acids.
Saturated fats are the ones you really have to look out for, and the American Heart Association recommends keeping them below seven percent of your total daily caloric intake. Not only are saturated fats connected with heart disease and increased cholesterol, but there is evidence that they may also increase the risk of colon and prostate cancers. This group also encompasses the infamous trans fats which are frequently used in fried and baked foods. Saturated fats are found in red meat, poultry, coconut and dairy products.
Eat Fat to Lose Weight?
So while the evidence suggests that small amounts of healthy dietary fat, accounting for about 25 percent to 30 percent of your daily calories, may be good for your heart, those numbers have been called into question. Some recent diets champion much higher levels of fat –closer to 50 percent — and recent research hints at merit in this approach.
The study was conducted at the Hebrew University of Jerusalem and was designed to test the impact that meal timing has on body composition. During the 18-week-long study, a group of mice was feed a high-fat diet on a strict schedule so that they received the food at the same time and were given a limited time to eat their meal. These results were compared to three control groups: one ate a low-fat, scheduled diet, one with an unscheduled, low-fat diet, and another with an unscheduled, high-fat diet.
At the end of the study the scheduled, high-fat mice weighed less than the other groups and had also entered a unique metabolic state where their dietary fat wasn’t stored but was immediately burned for fuel.
Before you take this information and switch to a high-fat diet, remember that no human studies have shown the same effects. Also, the study does not detail the source of fat that the mice received.
The study does suggest, however, that a properly controlled diet that includes rather than excludes fat could aid in weight loss. These findings go a long way to clear the name of fats.
Have you tried a diet high in healthy-fats? Please share your experience with us in the comments.