On the other hand, palm oil could be OK

Q: My wife and I have for decades avoided foods and oils high in saturated fat. Until recently, palm oil was rated as high in bad fats, but now I am reading that palm fruit oil is a well-balanced oil and is good for you. Please explain whether palm is a good oil for human health.

A: I like your question — and I have to admit that it is tough to answer for a few reasons. One is that whether something is good for you depends on what your underlying health issues are and what you are trying to achieve.

The second is that there is a lot of controversy right now about the effects of palm oil — and fat in general — on human health, and we don't have all the answers. Anyway, let me fill you in on some of the information we have so far.

First of all, as you make clear in your question, there are two types of oil derived from palm. One, palm kernel oil, is made from the seeds. The other, made from the fruit, goes simply by the name "palm oil." Even though both oils are high in saturated fat, palm kernel oil contains more.

Palm oil, the type made from fruit, is about half saturated fat, half unsaturated. The ratios for palm kernel oil are about 80-20. So when people talk about the palm oil that is good for you, they are usually referring to the fruit-derived oil.

This unrefined palm oil is also high in natural antioxidant compounds in the vitamin A family, known as carotenoids, and vitamin E compounds. The carotenoids in unrefined palm oil give it a pretty red color.

Regardless of the source, though, palm oil is still higher in saturated fat than many vegetable oils, and foods high in saturated fat can raise cholesterol. That said, it isn't clear yet whether palm oil actually raises cholesterol.

In some ways, that makes sense because, as I mentioned, palm oil also has 50 percent unsaturated fat. Of that, most is made up of a type called monounsaturated fat (specifically, oleic acid), while the rest is polyunsaturated fat (specifically, linoleic acid). Both of these have positive effects on cholesterol. So it may be that the effects of the fats counterbalance each other — though we still don't really know for sure. And most health organizations, including the American Heart Association, recommend avoiding palm oil because of its saturated-fat content.

Some people also argue that saturated fats are the safest for cooking because they don't oxidize, or get damaged, as easily with heating. They raise the concern that when people eat high amounts of oxidized fats, these fats can get incorporated into the cholesterol floating around in our blood vessels. Although it is still being studied, oxidized fats may be even more irritating to blood-vessel walls than nonoxidized fat, and promote more plaque buildup.

If oxidation is an issue, though, then unrefined palm oil may end up being a good choice for cooking because the natural antioxidants, including the carotenoids and vitamin E compounds, protect the oil from being damaged. Keep in mind though that refining the palm oil will remove that benefit. You can spot unrefined palm oil by its red color.

Dr. Astrid Pujari is a Seattle M.D. with an additional degree as a medical herbalist; she practices at the Pujari Center and teaches as part of the residency programs at Virginia Mason and Swedish/Cherry Hill hospitals. Send questions to apujari@seattletimes.com for possible use in future columns. All information is intended for education and not a substitute for medical advice. Consult your doctor before following any suggestions given here.