Tropical oils were once the favored fats for processed foods. Palm and coconut oil, for instance, had good shelf stability, creamy texture, and other features desired by food manufacturers. But starting in the late 1980s, these oils fell out of favor because of their saturated fats, which were linked to elevated blood cholesterol. The solution, at the time, was to replace them with partially hydrogenated vegetable oils, which have similar qualities as tropical oils. Partially hydrogenated oils became ubiquitous in processed foods—until it was discovered that the trans fats they contain are even worse for the heart than tropical oils.
The latest solution? Some manufacturers have been turning (or returning) to tropical oils, touting them as a healthier alternative to partially hydrogenated oils. You’ll find them in an increasing number of packaged foods, including crackers, cookies, pie crusts, energy bars, and spreads, as well as in microwave and movie theater popcorn. Is this a wise move?
Understudied and unclear
Some lab research has suggested that palm oil, though highly saturated, may act more like healthful unsaturated fats in the body, in terms of its effects on blood cholesterol. But the evidence is conflicting, and the few clinical studies have been small. Meanwhile, population studies have not consistently linked consumption of palm oil to heart disease. In reality, there have been too few human studies in English-language journals to know if palm oil is detrimental, neutral, or possibly even beneficial.
Types of Palm Oil
The term "palm oil" actually encompasses several types of oil derived from the palm tree, including palm oil, palm kernel oil, and fractionated palm kernel oil. Here's a quick rundown of each.
Published research on coconut oil is even more scant. In one study, in the journal Lipids, women who consumed 1 ounce of coconut oil a day for 12 weeks had no undesirable changes in cholesterol. And in places where people consume a lot of coconut oil, such as Sri Lanka and Polynesia, cholesterol levels tend to be low. There’s no evidence, however, that coconut oil strengthens immunity, improves digestion, treats HIV and herpes infections, or prevents heart disease, arthritis, or other chronic diseases, as some websites claim. Due to its chemical structure, it does take a few more calories for the body to process coconut oil, compared to other fats—but any calorie-burning effect would be minimal at best. It is certainly no treatment for obesity. For more on coconut oil, see Is Coconut Oil a Miracle Food?
A breakdown of tropical oils
All fats are mixtures of saturated and unsaturated (poly- and monounsaturated) fatty acids. Though most of the fatty acids in tropical oils are saturated, not all saturated fats are harmful. In some studies, palm oil’s main fatty acid, palmitic acid, had no effect on cholesterol. Palm oil also contains a fair amount of monounsaturated fats. Similarly, though coconut oil is highly saturated, its fats seem to be neutral overall—that is, they don’t worsen or improve cholesterol levels in most people. Coconut oil’s main fatty acid, lauric acid, may even have some health benefits.
As we’ve reported previously, just because a food is high in saturated fat doesn’t necessarily mean it increases blood cholesterol or contributes to heart disease. The effect of saturated fat varies from person to person, depending on genetics, weight, other dietary and lifestyle factors, and even gender (saturated fat tends to increase LDL, the “bad” cholesterol, more in men). In addition, tropical oils contain other substances that can affect the risk of heart disease—and how the oils are processed may matter, too. What’s key is your overall diet. Adding tropical oils in the context of a healthy diet is unlikely to affect blood cholesterol significantly.
Our advice:Early research that raised red flags about tropical oils was faulty. You should still limit these oils, however, since their effects on cholesterol are not fully understood. Snack foods that contain these oils tend to be high in calories and low in nutrients anyway. You can use coconut oil in cooking on occasion if you like the flavor, though we recommend vegetable oils such as canola, olive, soy, or safflower for regular use.
Also see Fats and Oils:Why We Love Them.
Published September 01, 2016