Berkely Wellness Alert about tropical oils
October 7, 2011 | Comments: 0
Tropical Oils: Healthful or Not?
Tropical oils are being touted as a healthier alternative to partially hydrogenated oils, which contain trans fats. Are they really better for you?
Tropical oils were once the favored fats for giving processed foods a pleasing texture and good shelf stability. But starting in the late 1980s, these oils fell out of favor because most of the fats they contain are saturated, and saturated fats were linked to elevated blood cholesterol. Partially hydrogenated oils, which largely replaced tropical oils at the time, were subsequently found to be even worse for your heart because of their trans fat.
Now, tropical oils are back again. You can find them in an increasing number of packaged foods, including crackers, cookies, pie crusts, energy bars and spreads, as well as microwave and movie theater popcorn.
Tropical oils: understudied and unclear
Lab research suggests 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. One study from Brazil, for example, found that palm oil improved cholesterol in healthy people. In contrast, a study from Thailand found it increased cholesterol in women who already had high cholesterol. 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.
Published research on coconut oil is even more scant. In one study, in Lipids, women who consumed coconut oil for 12 weeks had no undesirable changes in cholesterol. And in some countries where people consume a lot of coconut oil, cholesterol levels tend to be low. There’s no evidence, however, that coconut oil strengthens immunity, improves digestion 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.
A breakdown of tropical oils
All fats are mixtures of saturated and unsaturated 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 have a neutral effect on cholesterol levels in most people.
Moreover, the effect of saturated fat varies from person to person, depending on genetics, weight, other dietary and lifestyle factors and even gender. 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 aren’t fully understood. And snack foods containing tropical oils tend to be high in calories—and low in nutrients. Be aware, also, that manufacturers may use a process called interesterification, which changes the structure of the oil so that it performs like a partially hydrogenated oil without the trans fat. That sounds great but we don’t yet know whether interesterified fats might have their own adverse health consequences. If you see the term “fully hydrogenated” palm or palm kernel oil on a food label, it may indicate that interesterified fats are present.
Berkeley Wellness Alerts - Tropical Oils: Healthful or Not?
Don't eat coconut oil because of positive health effects but eat it because you like it.
