We sat down with Courtney McMahan, RD at Nutrition World to talk about fat!
So, what are healthy fats and how do they differ from unhealthy fats?
The only fats that are unhealthy in all contexts are trans fats, examples incldude partially hydrogenated vegetable oils and margarine. Trans fats have been shown to lower HDL cholesterol (commonly called "good" cholesterol) and increase LDL cholesterol (or "bad" cholesterol"). These fats are not beneficial and when possible, should be completely avoided.
Many people refer to saturated fat as "bad" fat, but this isn't necessarily the case. Saturated fat can have a negative impact on blood lipids if eaten in excess, but many foods containing saturated fat are incredibly nutritious. A general guideline to go by is to get no more than 10% of your daily calories from saturated fats. These mainly come from animal products, but they are also found in some oils that are solid at room temperature, like coconut and palm oil.
There are many examples of healthy fats including avocados, nuts, seeds, and olive oil - but let's break it down. We have two sources of fat: monounsaturated and polyunsaturated. Monounsaturated fats come come primarily from vegetables, nuts, and seeds and they have been shown to increase HDL (your good cholesterol). Polyunsaturated fats - these are essential fats- meaning your body cannot make them and you must get them from food: omega 3's from fatty fish, and omega 6's from foods like walnuts, sunflower seeds, and pumpkin seeds.
Should we be scared of fat?
Just because dietary fat is called by the same name as body fat does not mean that you should steer clear of it. There are many different types of fat, and different types will have very different effects on health. The fat from french fries that have been deep fried in oil is going to be a lot different than the fat in an avocado or a handful of nuts. Our brain is made from 60% fat, fat helps us to absorb our fat soluble nutrients, essential fatty acids are required to resolve inflammation in our bodies, and they help make up the membrane around each of our cells.
How much fat should we aim for in our diets?
For most people, getting about 20-35% of your total calories from fat is optimal.