Trans Fat Alternatives

[Trans-Fat Alternatives and Organics mp3]

Today’s episode is a discussion about the types of fat currently being used in food manufacturing and the restaurant industry to replace trans-fatty acids. We also discuss a recent meta-analysis published in the Annals of Internal Medicine about organic foods.

Carrie has written a great piece outlining the issue in Nutrition Nuts and Bolts, a blog run by another fellow UW Nutrition Science student.

I’d like to expound a bit on the chemical structure of fatty acids and why that is important.

The Basics

Fats are essentially chains of carbon. All carbon atoms must have four bonds; no more and no less. This means that when carbon is organized in a long chain two of the available bonds are attached to other carbons, and the remaining two bonds are attached to the most abundant atom in the universe: hydrogen. This type of fat, when all the available bonds are saturated with hydrogen, is known as a saturated fat.

The picture below is a representation of a saturated fat called palmitic acid. The black balls represent carbon, the white balls represent hydrogen, and the red balls at the end represent oxygen.

When fats are saturated they naturally take the shape of a kind of flat zig-zag structure because this is the most stable form.  This can allow for the fatty acids to neatly stack against each other, making them nearly always solid at room temperature.

By contrast, unsaturated fatty acids have one or more double bonds in the carbon chain. This produces kinks that prevent the fatty acids from forming a solid.

The main difference then, chemically speaking, between butter and oil is that the fatty acids in oil are chock-full of double bonds.

Where do trans-fats come in?

In the latter half of the 20th century saturated fats began to acquire a bad reputation. Various kinds of studies began to show that saturated fat was associated with heart diseases and cancers.1 Unsaturated fats, on the other hand, were largely considered to be healthier. Two problems though: when making biscuits or cookies or any number of other baked goods you really cannot substitute oil for butter.2 The second problem was that unsaturated fats are prone to oxidation and rancidity.

What do we do about this? Well, there was a process called hydrogenation that developed in the early 20th century to try and increase the shelf life of vegetable oils and fish oils. The resulting fats were actually more shelf-stable (because they were resistant to oxidation), cheaper to produce, were delicious, and could easily replace butter or lard in a recipe. This made them desirable to the food industry. Moreover, the fatty acids, although structurally similar to saturated fatty acids, were in fact unsaturated.

From Wikipedia:

In most naturally occurring unsaturated fatty acids, the hydrogen atoms are on the same side of the double bonds of the carbon chain (cis configuration — from the Latin, meaning “on the same side”). However, partial hydrogenation reconfigures most of the double bonds that do not become chemically saturated, twisting them so that the hydrogen atoms end up on different sides of the chain. This type of configuration is called trans, from the Latin, meaning “across.” The trans configuration is the lower energy form, and is favored when catalytically equilibrated as a side reaction in hydrogenation.

The fact that these fats were technically unsaturated led some health advocates to push for saturated fat to be replaced with trans-fat in common food products. Unfortunately, as we all know now trans fats are far worse than saturated fats in almost every way, at least in terms of human health.

Recently we’ve all been privy to the slow removal of trans fats from the food industry. Carrie and I discuss how it’s being done and what the implications might be.

Like I mentioned earlier, we also discussed organic foods and their latest controversy, but that portion will have its own forthcoming blog post.

  1. I’m not going to discuss the reasons for it in this blog post, but suffice it to say when saturated fats (as opposed to unsaturated fats) become incorporated into the lipid membranes of cells it starts to disrupt cell function. Membranes need to have a certain amount of fluidity and flexibility, but if they made up of mainly saturated fats then the cell membrane becomes rigid and it’s more difficult to do housekeeping chores like importing nutrients, exporting waste, cell signaling, etc. This is not the only reason for saturated fats negative health effects, but it’s a major one.
  2. Actually you can, but you won’t like the results.

5 thoughts on “Trans Fat Alternatives

  1. “Membranes need to have a certain amount of fluidity and flexibility, but if they are made up of mainly saturated fats, then the cell membrane becomes rigid and it’s more difficult to do housekeeping chores like importing nutrients, exporting waste, cell signaling, etc.”

    You might want to check out this assumption. While there may be some truth in it, the fact is that high saturated fat consumption does not necessarily translate into high levels of saturated fats in the bloodstream, the supply source for cellular building materials.

    Cell membranes also contain omega-3s and 6s proportionate to what humans or animals ingest. High levels of omega-6 intake correlate with inflammation.

    I injured myself by consuming peanut butter sandwiches almost daily for 4 decades. Fortunately, I watched the above Bill Lands video and realized my mistake when he mentioned that peanuts contain 4,000 milligrams of omega-6 in each 28 gram one ounce serving of peanuts. That was nearly three years ago. I’ve since regained considerable strength and stamina and have been researching the omega-6 hazard ever since. Google: “David Brown Omega-6” for more info on the matter.

    • I was lazy this week and neglected to include sources for my claims. Let me remedy some of that now.

      Here are a couple of review papers on the roles that lipids play on membrane structure and cell function:
      Spector, A. A. and M. A. Yorek (1985). “Membrane lipid composition and cellular function.” Journal of Lipid Research 26(9): 1015-1035.
      Hagve, T. A. (1988). “Effects of unsaturated fatty acids on cell membrane functions.” Scand J Clin Lab Invest 48(5): 381-388.

      Here are a three review papers explaining how dietary fats affect health outcomes via membrane dysfunction:
      Clandinin, M. T., S. Cheema, C. J. Field, M. L. Garg, J. Venkatraman and T. R. Clandinin (1991). “Dietary fat: exogenous determination of membrane structure and cell function.” FASEB J 5(13): 2761-2769.
      Haag, M. and N. G. Dippenaar (2005). Dietary fats, fatty acids and insulin resistance: short review of a multifaceted connection. Med Sci Monit. Poland. 11: RA359-367.
      Storlien, L. H., A. J. Hulbert and P. L. Else (1998). “Polyunsaturated fatty acids, membrane function and metabolic diseases such as diabetes and obesity.” Curr Opin Clin Nutr Metab Care 1(6): 559-563.

      And here are two showing how trans-fats are bad for health:
      Hu, F. B., J. E. Manson and W. C. Willett (2001). “Types of dietary fat and risk of coronary heart disease: a critical review.” J Am Coll Nutr 20(1): 5-19.
      Micha, R. and D. Mozaffarian (2008). Trans fatty acids: effects on cardiometabolic health and implications for policy. Prostaglandins Leukot Essent Fatty Acids. Scotland. 79: 147-152.

      While I did not mention n-6 FAs, you’re right that they are used to make pro-inflammatory cytokines. This is why I find it amusing (and unfortunate) when I see people buying supplements containing omega-3, omega-6, and omega-9. The first one is great, the second is essential but you don’t want too much of it, and the third is not even an essential fatty acid! Humans can synthesize it easily.

  2. Seth,

    There’s growing realization that saturated fats do not have any negative health effects as long as they are consumed in the context of adequate supportive nutrition.

    For many years it was assumed that because saturated fats (and that’s only three chain lengths of saturated fat) raise cholesterol, they must be atherogenic. But recent research has shown that restricting saturated fat intake has very little effect on cholesterol compared to other dietary factors. Moreover, higher levels of LDL-C may have benefits in terms of preserving muscle mass:

    • David,
      This post is about the chemical structure of fatty acids, not the health effects of saturated fats. If you want to write comments about SFAs then that is fine. You are free to write all you want, but just to be clear I’m not demonizing SFAs here.

      As an aside, I did visit this link: And the author seems like a smart fellow. However, in the third paragraph he states “the scientific evidence now establishes that dietary saturated fat has no effect on cardiovascular disease” and hyperlinks to this meta-analysis to support his claim. Interestingly the paper concludes that if you replace 5% of the saturated fat in your diet with unsaturated fat (polyunsaturated fat in this case) then you significantly reduce your risk of both coronary events and coronary death. I wonder if Dr. Feinman even read the paper or if he simply linked to the wrong one.

  3. Hi Seth,

    You said, “This post is about the chemical structure of fatty acids, not the health effects of saturated fats.”

    True, but you did mention the health effects of saturated fats when you remarked, “This is not the only reason for saturated fats negative health effects, but it’s a major one.” I responded to that statement because I don’t believe there are any negative health effects associated with saturated fat intake as long as they are consumed, as previously noted, in the context of adequate supportive nutrition.

    I contacted Dr. Feinman and he said his mistake was in not giving more information. He referred me to this previous post:

    His comment: “This was a meta-analysis that asked us to believe that if you average up a bunch of studies that show no correlation between saturated fat and CVD, you can turn a bunch of zeros into a real number that the computer will tell you is statistically significant.”

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