Think all fat is bad? This article provides a detailed comparison between good and bad fats. Learn more about the dangers of trans fat and saturated fat and why you should be consuming more unsaturated fats.
Contrary to popular belief, not all fats are bad for your health. While some can clog your arteries with plaque and contribute to heart disease, others are good for your health and reduce the risk of chronic illness. So, if you’re looking to live a longer, healthier life, you should familiarize yourself with the different types of fat.
There are two types of fat that are considered bad: saturated and trans fat. Saturated fats are characterized by their unique molecular composition in which their fatty acids have single bonds. They also have a higher melting point than good fats, meaning it takes higher temperatures to melt them.
While not as harmful as trans fat, saturated fat raises LDL cholesterol levels in the blood, which increases the risk of heart attack, stroke, and coronary heart disease. Cholesterol is an essential nutrient that supports healthy cellular activity. Too much LDL cholesterol, however, causes a buildup of fatty plaque in the arteries and subsequent heart problems.
You don’t have to avoid all sources of saturated fat, however; that would be nearly impossible without going vegan. The American Heart Association (AHA) recommends consuming 5% to 6% of your daily calories from saturated fat. For individuals on a 2,000-calorie-per-day diet, that’s roughly 13 grams of saturated fat.
Foods containing high concentrations of saturated fat include:
- Whole milk
- Potato chips
- Coconut oil
- Palm kernel oil
Another bad fat is trans fat, which is worse than its saturated fat counterpart. Also known as trans-unsaturated fatty acids, trans fat is made by adding hydrogen to unsaturated fat in a process known as partial hydrogenation. This addition of hydrogen prolongs its shelf-life and prevents spoilage.
Trans fat naturally occurs in animal fat, though typically in small concentrations. In baked and processed foods, however, levels are higher. Trans fat offers zero nutritional value and has even been linked to heart disease. While saturated fat raises LDL cholesterol levels, trans fat raises LDL cholesterol and lowers HDL cholesterol. HDL is considered the good type of cholesterol, whereas LDL is the bad type.
A 1994 study published in the American Journal of Public Health estimates that trans fat is responsible for more than 30,000 heart-related deaths per year in the United States. The U.S. Food and Drug Administration (FDA) issued a warning to the public in 2013, stating trans fat is not safe for human consumption. In 2015, the FDA took the first steps towards banning the ingredient in processed foods. Food companies have three years to comply with the new rule.
Foods containing high concentrations of trans fat include:
- Microwaveable popcorn
- Pies (specifically the crust)
- Non-dairy creamer
The World Health Organization (WHO) recommends limiting your intake of trans fat to no more than 1% of your daily caloric intake. Keep in mind that some foods and beverages labeled as having 0 grams trans fat may still contain this harmful substance. The FDA allows companies to list their products as having 0 grams of trans fat if they have less than 0.5 grams. You can usually tell if a food or beverage product contains trans fat by looking for “partially hydrogenated” in its listed ingredients.
There are also good fats that you should consume: monounsaturated and polyunsaturated fat. Technically speaking, the molecular composition of monounsaturated fat consists of a single unsaturated carbon bond. These fats usually remain liquid at room temperature but turn solid when frozen.
Polyunsaturated fats use two or more unsaturated carbon bonds in their molecular structure. Like monounsaturated fat, they are liquid at room temperature but turn solid when frozen. Polyunsaturated fats are also considered essential, meaning the human body needs them to perform certain functions, like building cell membranes and protecting the nerves from damage.
The two primary types of polyunsaturated fat are omega-3 and omega-6 fatty acids. Other than their molecular size, omega-3 and omega-6 fatty acids are the same.
Monounsaturated and polyunsaturated fats are beneficial to your health because they reduce LDL cholesterol levels and raise HDL cholesterol. According to a 2016 meta-analysis conducted by the AHA, individuals who replaced their intake of saturated fat with monounsaturated and polyunsaturated fat were 30% less likely to develop heart disease than their counterparts who did not make this change.
Foods containing high concentrations of polyunsaturated and monounsaturated fat include:
- Soybean oil
- Olive oil
- Canola oil
- Peanut oil
- Sesame oil
- Nuts (almonds, walnuts, pistachios, peanuts)
- Nut butter
- Dark chocolate (not milk chocolate)
To recap, bad fats consist of trans fat and saturated fat, while good fats include monounsaturated and polyunsaturated fat. If you’re looking to improve your health and protect against chronic disease, you should avoid all sources of trans fat, limit your intake of saturated fat, and consume more monounsaturated and polyunsaturated fat. Doing so will have a positive effect on your cholesterol levels, promoting a healthier heart with a lower risk of disease.