We're back at the trans fat farm

I got my copy of the Annals of Internal Medicine today and, for once, read at least the summary of almost all the articles. One in particular caught my eye. It's a report of a prospective study that was multi-institutional (Harvard, the NIH, University of New Mexico and University of Washington with associated branches for two of the schools), fairly large (3,736 adults), multi-racial and lengthy (1992-2006). The study group was limited to adults over 65 who were living in the community, not in institutions. It was termed a "cohort study" and one definition of that is "A study in which a particular outcome, such as death from a heart attack, is compared in groups of people who are alike in most ways but differ by a certain characteristic, such as smoking."

In other words it's not a prospective controlled study, which I view as a higher level of medical research; in those you decide in advance what the object of the study is and select groups again in advance who will differ in some important aspect (e.g., they will or will not receive a particular medicine that's being studied or they'll be put on differing diets with one group getting whole milk and the other low-fat or non-fat milk). That may seem a subtle distinction, but it's an important one to me.

In any case the outcome was fascinating, though I'd term it preliminary.

Remember I mentioned trans fats (or more precisely trans fatty acids) as being bad guys. Well here's a case where one particular trans fat may be a good guy.

Most trans fats in the diet of Americans are/were artificially produced (I say were because a number of places (NYC and California) have almost totally banned them (less then 0.5% is allowed in the CA law). The FDA required strict labeling of these in 2006.

But small amounts are found in milk and  red meat. This study appears to demonstrate that a  particular trans fat called trans-palmitoleate, found in whole milk is associated with a lower risk for developing diabetes in adults. The effect wasn't found with red meat consumption or low-fat milk consumption.

Now that's very interesting, but it doesn't prove this particular fatty acid itself is healthful, only that, in this admittedly large and well-conducted study, that it's "associated with" several good metabolic effects, i.e., less diabetes and less obesity. The fatty acid could be a marker for consumption of something else that causes the effect.

More studies need to follow this one, of course, but the authors suggest that if those were to show the same effect, a case might be made for enriching/supplementing milk with this fatty acid. They also mention that, until this issue is resolved, the current push toward drinking only low-fat or even no-fat dairy products may be viewed differently.

No pun intended, but I need to digest this information a little before making a choice for myself.

This entry was posted on Monday, December 27th, 2010 at 9:19 pm and is filed under Food Additives, Healthy eating, medically-oriented background info. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.