The Science of Fats:
What’s the Difference Between Saturated,
Unsaturated, & Trans-Fats?
Most of us have heard the terms saturated, unsaturated, and trans-fat used before. If you aren’t sure exactly how they differ or which fats are found in certain types of foods this is a good place to start. Fatty acids are characterized as either saturated (solid at room temperature) or unsaturated (liquid at room temperature) based on the presence of double bonds in its structure. If a molecule contains no double bonds, it is considered saturated. If it contains one or more double bonds, it’s said to be unsaturated. (See image below).
Tran-fats are unsaturated fats that have been chemically engineered to become saturated fat. For example, vegetable oil, which is liquid at room temperature, undergoes a process that changes the molecule to make it saturated (solid at room temperature), turning it into margarine. This process makes foods less prone to spoilage.
Although trans-fats occur naturally in trace amounts in some meat and dairy products, the majority of them are often found in highly processed foods, fried food, stick margarine, commercially baked foods like donuts, cookies, and crackers. They are used to make these more shelf stable. In addition, they have been shown to raise LDL (bad) cholesterol and increase the risk of heart disease. The Institute of Medicine (IOM) has concluded that there is no safe level of consumption of artificial trans-fats. The IOM also recommends that consumption of trans-fats be as low as possible while consuming a nutritionally adequate diet.
Food Sources of Unsaturated (healthy) fat include:
Unsaturated fat, also referred to as essential or “good fat” can have beneficial effects on our health including acting as an anti-inflammatory, improving cholesterol or lipid values, and better heart health. These good fats are found in mostly plant sources like nuts, seeds, oils, avocado and olives, with the exception of fatty fish like salmon.
Food Sources of Saturated (unhealthy) fats include:
Saturated fat, which can have negative health consequences when eaten in high amounts over a period of time, can contribute to an increased risk for heart disease, stroke, and abnormal cholesterol or lipid values. It’s found in meat, cheese, animal products and processed food like baked goods or chips, as well as tropical oils like palm and coconut oil.
Too much fat, saturated or unsaturated, is stored in the body and can lead to gain weight which can increase the risk for other adverse health problems. Protein, carbohydrates, and fat are all important components of a healthy diet, but must be eaten in balance and moderation. Eat responsibly!