Are seed oils bad for me?
Have you ever noticed how many different cooking oils there are in the grocery store? Vegetable oil, canola oil, olive oil, sunflower oil… the list goes on and on. So, which ones are the best to choose? Is vegetable oil really inflammatory like those “experts” say, and is olive oil the only good option for you to cook with? Today, I’m here to break down all things oil and help you select the best ones to keep in the house for cooking and meal preparation.
Oils are a source of dietary fat. There are 3 different types of fat, and each one has its own impact on our health. Let’s start by breaking down each type:
Monounsaturated fat is a type of dietary fat. From a chemical standpoint, “monounsaturated” simply means having one unsaturated bond in the fat molecule. Because of this bond, the fat remains liquid at room temperature. In our bodies, monounsaturated fat helps maintain cell structure and reduce levels of LDL-cholesterol in the blood. Oils that are monounsaturated include olive oil, canola oil, and avocado oil. There are even some nut oils that are monounsaturated, including walnut and hazelnut, but these aren’t typically recommended for cooking due to their low smoke point. Instead, you can use them for cold dishes like salads.
Polyunsaturated fat is another source of dietary fat. Its chemical composition has more than one double-bond in the molecule (“poly” = “many”). Similar to monounsaturated fat, polyunsaturated fat is liquid at room temperature and helps remove LDL-cholesterol from the blood. It is also where we get our dietary sources of omega-3 and omega-6 fatty acids, which are known to reduce inflammation and promote heart, brain, and metabolic health. Canola oil, sunflower oil, soybean oil, and corn oil are polyunsaturated oils.
Saturated fats are the only fat source that us dietitians recommend using sparingly. Saturated fats have no double-bonds in their structure, which causes them to be solid at room temperature. Research has found that a diet high in saturated fat intake may increase a person’s risk for heart disease. Coconut oil, palm oil, palm kernel oil, butter, and lard are all saturated fat sources. Typically, it is recommended to limit these fats as much as possible, or to less than 10% of our daily calorie intake.
The debate over seed oils is one we have seen pop up from time to time, and although some influencers or individuals who tout themselves to be “experts” might say they aren’t good for our health (remember to always look for that RD credential when taking any nutrition advice), there is no actual evidence to support that seed oils are harmful to humans in any way. Some studies have shown a correlation between seed oils and inflammation, but there are a few reasons why we shouldn’t worry. First, many of these studies take place in rodents. Human metabolism doesn’t work the same way rodent metabolism does, and findings are typically unable to be replicated in human subjects. Another important thing to remember is that diet is not the only source of inflammation in the body. Stress and environmental toxins can also negatively impact inflammatory markers, and these variables may not always be controlled for in research. Although some studies have shown a correlation between seed oil intake and inflammation, there are equally as many studies that show it has no effect on inflammation at all.
Our answer to the blog title question is rather simple: go with your preference, and try to stick to the unsaturated sources on the shelf. If you are cooking with an oil, take into consideration its smoke point and whether or not it will work well for cooking. A combination of monounsaturated and polyunsaturated fats have been shown to positively impact our heart health. Hopefully, you find a cooking oil that you and your family enjoy!
Until Next Time, Emily Sicinski, MS, RDN, CDN