Health Hotline Magazine | July 2025

The Heart of the Matter Vegetable oils are promoted as “heart healthy,” in part because they were shown in early studies to lower cholesterol. However, we now know that cholesterol is not the main driver of cardiovascular disease and new analyses of research show a more complex reality. Take for example the Minnesota Coronary Experiment (MCE), conducted from 1968 to 1973. This trial reported that replacing saturated fat with vegetable oil (specifically corn oil) reduced coronary heart disease and death by lowering serum cholesterol. But a fresh analysis of the study, published in 2016, reviewed unpublished data on the 9,423 participants of the MCE and found that while replacing saturated fats with vegetable oils did indeed lower cholesterol levels, there was “no mortality benefit for the intervention group.” And in fact, “There was a 22% higher risk of death for each 30 mg/dL reduction in serum

cholesterol…” and “There was no evidence of benefit in the intervention group for coronary atherosclerosis or myocardial infarcts [heart attacks].” In analyses of other studies, “these cholesterol lowering interventions showed no evidence of benefit on mortality from coronary heart disease or all-cause mortality.” The researchers concluded by saying that findings from the Minnesota Coronary Experiment “add to growing evidence that incomplete publication has contributed to overestimation [of benefits], and underestimation of potential risks, of replacing saturated fat with vegetable oils rich in linoleic acid [the main omega-6 found in vegetable oil].” A review published in 2018 in the journal Open Heart presented research that showed vegetable oils high in omega-6 fats may actually drive the development of atherosclerosis and coronary heart disease in part by promoting oxidative damage and inflammation in the endothelium (the lining of our blood vessels) and increasing the oxidation of LDL cholesterol. Other research has similar findings, showing that the consumption of vegetable oils high in omega-6s increase inflammation in the aorta and endothelium, contribute to low-grade inflammation, oxidative stress, and endothelial dysfunction.

Omega-6 a Root Cause of Degenerative Diseases A 2020 review investigated vegetable oil’s potential role in the development of lifestyle diseases including obesity, type-2 diabetes, non-alcoholic fatty liver disease, and Alzheimer’s by increasing damage to cells. The review describes how vegetable oils like corn, soybean, and sunflower create a substance called hydroxynonenal when heated, which researchers believe plays a key role in cell degeneration and death. Further, even vegetable oils that are not deep fried (like those found in mayonnaise, salad dressing, etc.) will be incorporated into cell membranes and LDL cholesterol, where they increase inflammation and oxidative damage. The researchers conclude that decreasing the consumption of omega-6 oils while increasing the consumption of omega-3 oils is critical in preventing various lifestyle diseases. This is key because both types of fat compete for space in cell membranes; in other words, if you are consuming more omega-6 fats compared to omega-3 fats, your cell membranes will mostly be comprised of pro-inflammatory omega-6s. Find a Healthy Balance

A Note On Omega-9 Fats

While much focus is on the omega-6 and omega-3 fatty acids, omega-9 is another important one to know. Omega-9 fats are a type of monounsaturated fatty acid and have their own health benefits including supporting cardiovascular health and a healthy weight; the most common omega-9 fat is oleic acid. Olive oil is one of the best-known sources,

containing 55 to 83 percent oleic acid. High-oleic sunflower and sa ower oils are specifically made to

As with most things in life, balance is key. Start reading labels— once you start looking for vegetable oils, you will find them everywhere (I recently found soybean oil in the ingredient list of Italian sausage). In general, most processed foods (packaged snacks, cookies, salad dressings, crackers, chips, etc.) will contain some type of vegetable oil. The same goes for fast food and restaurant food. Avoid these as much as possible. At home, choose oils such as coconut oil, butter, high oleic sunflower or high-oleic sa ower oils, and extra virgin olive oil for cooking. In general, look for oils that contain a higher amount of saturated and/or monounsaturated fat in relation to polyunsaturated fats (which are typically omega-6). Last but not least, take a quality omega-3 fish oil supplement. The large majority of us simply don’t eat enough cold-water fatty fish (one of the main food sources of omega-3s) to get optimal amounts. A supplement will ensure that you saturate your cell membranes with the good stu !

reduce omega-6 content while increasing omega-9 as oleic acid; they typically contain a minimum of 80

percent oleic acid. Be sure to look for “high-oleic”—regular sunflower and sa ower oils are very high in omega-6 fats. When checking the nutrition label, look for a higher amount of monounsaturated fat (omega-9) versus polyunsaturated fat (typically omega-6). These oils are healthy alternatives to high omega-6 oils like corn, soybean, and canola oils.

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For references, please visit naturalgrocers.com/issue-96