I learn a lot from writing these columns.

For example, to prepare for this topic, one of the first things I did was to find out exactly what types of vegetables go into making “vegetable oil.” Turns out the answer is none. There are no vegetables in vegetable oil. That was a bit of a surprise for me, I just assumed that at least some of these oils had a little veggie juice in them.

So the next question is, why do they call it vegetable oil if there are no veggies in it?

The United Soybean Board (and other pro-vegetable oil references) completely duck the issue, just saying that all plant-based oils (corn, canola, olive, etc.) were called vegetable oils to differentiate them from lard-based shortenings. They don’t speak to the issue that these are not vegetable oils, or why they aren’t called plant oils.

The majority of these oils are better described as seed oils. These include the most commonly used oil — up to 85 percent of “vegetable oils” are from soybeans. The other seed oils are less common, like corn, sunflower, safflower and canola oil. A few are actually from fruit; this includes olive, coconut and palm oils.

Some of these oils have been around for centuries, especially olive oil. Olive oil can be extracted by a relatively simple high-pressure method. Most of the seed oils are newer, because the only way to extract the oil in any quantity is through a multi-step chemical process. This often starts with hexane, a solvent that dissolves the oil, and, depending on the seed, may proceed to degumming, bleaching, removal of waxes and deodorizing by high-pressure steam in a vacuum. (By themselves, these oils tend to taste terrible; they need a lot of processing to be edible.)

Sounds less and less like food to me.

Despite the medical position that vegetable oils are healthier than the animal-based fats, the research is not consistent. Some studies show vegetable oils have health benefits, others suggest saturated fats are healthier. So I fall back to the basic wellness principles I was taught — that the healthiest foods tend to be the least processed. Also, foods that our great-grandparents ate are likely to be healthier than our newer foods.

The seed-based vegetable oils fail on both of these counts. I certainly don’t buy the idea that animal fats are major contributors to heart disease; there are too many accounts of amazingly healthy Native American or African tribes who ate animal products almost exclusively.

So I don’t use or recommend the newer seed oils. I stick with the traditional animal and fruit-based fats: butter, olive, coconut and palm oil. I recommend avoiding any oils that have been extracted with solvents. Some olive oil is made through chemical processing because it is cheaper and more efficient. Unfortunately, many olive oil producers fudge the labels and mix “real” olive oil with other oils, or with olive oil made through hexane extraction.

Modern nutrition seems to be an area where half-truths reign. From “vegetable oils” that have no trace of any veggies, to “healthy oils” that are the end product of extensive processing, to “fake” olive oils, it seems profit and convenience take precedence over health. I feel very fortunate that Maine has such a strong organic farming community, as well as one of the strongest organic associations in the country, to provide a counter to this commercialization of our foods.

Dr. Michael Noonan practices chiropractic, chiropractic acupuncture and other wellness therapies in Old Town. He can be reached at noonanchiropractic@gmail.com.