05.16.07
Trans-fat Bans
Following the example set by New York City, the City of Brookline is considering its own trans-fat ban. What are the implications of this? Does it make sense for a minor municipality to enact such a ban?
Trans-fat Science in a Nutshell
Fat molecules are made up of three “fatty acids”, each attached at one end to a glycerol molecule. In a “saturated” fat, the long carbon chains in the fatty acids contain only single bonds, allowing the molecules to rotate freely (like a single-pole stool). In an “unsaturated” fat, one or more double bonds are present in the chain. These inhibit rotation at that position in the molecule, locking it into a fixed shape. Naturally occurring vegetable oils have double bonds in the ‘cis’ (same-side) position, forcing the chain into a ‘U’ shape. In a trans-fat, the double bonds are connected in the ‘trans’ (opposite-side) position, resulting in a straighter chain. The difference between these two configurations results in a higher melting point for trans-fats, however they are also far more damaging to the arteries. A 2% increase in calories from trans-fats (roughly 4.5 grams a day, or the equivalent of one cake donut) is believed to double the risk of coronary heart disease.
While some trans-fat occurs naturally in the milk and meat of ruminant animals (cows, sheep, goats), approximately 75% to 90% of the trans-fats in our diets are produced artificially through the hydrogenation of vegetable oils. The goal of this hydrogenation is to convert some of the double bonds in unsaturated fats to “saturated” single bonds (by adding hydrogen atoms at that position in the molecule). Unfortunately the hydrogenation process that is commonly used is not selective. While some of the double bonds get saturated, others switch from the ‘cis’ position to the ‘trans’ position. When you read “partially hydrogenated oil” on a food package, this is a strong indication that the food contains artificial trans-fats.
Implications of a Ban
Partially hydrogenated fats have three distinct advantages over natural oils. First, they are solid at room temperature. Cookies made with Crisco are lighter and fluffier than cookies made with oil. Pie crusts are flakier with Crisco than with butter. Partial hydrogenation of the oils in Skippy peanut butter prevents it from separating on the shelf. Second, they go rancid more slowly, and thus baked goods or candies made with partially hydrogenated fats have a longer shelf life. Third, they last longer in the deep fryer before breaking down. Restaurants naturally prefer to replace their frying oil as seldom as possible!
You cannot simply wave a wand and make trans-fats disappear. Food companies have been working feverishly over the last two years to reformulate their products without trans-fats (or with less than 0.5 gram per serving, a level that permits them to list the product as “0 g” on the nutrition facts label). They have in most cases been able to come very close to the original, but it is not an easy task. Restaurants and bakeries face a similar challenge, revisiting many of their recipes and procedures. Alternatives do exist, such as the use of 1% linolenic acid soybean oil for frying, but they may not be widely available yet.
Moving Forward
Nutritional science strongly supports the elimination of trans-fats from our diet. They are simultaneously unnecessary and unhealthful, even in moderate quantities. Yet the federal government has been reluctant to take the lead in this. The inclusion of trans-fats on the FDA Nutrition Facts Label was a start, but this mandate did nothing to address the use of trans-fats in bakery and restaurant food. It was not until the New York City Board of Health enacted their ban on artificial trans-fats that we began to see action on this front. New York City is too significant a market for large chains to abandon, so they have no choice but to find a way to comply. Once that mandated transition is complete, we can expect that most chains will voluntarily eliminate trans-fats at all their locations nationwide.
Equally important, the New York City ban will create a strong demand for trans-fat free oils, sauces, and desserts. This will elevate such products from “niche” status into a standard line carried by mainstream food service distributors. A family restaurant might be reluctant to eliminate trans-fats from their menu if that would require ordering from specialty suppliers, but this should soon cease to be a concern.
The City of Brookline is just one suburb of a lesser city, yet the NYC initiative makes it reasonably possible for them to follow suit. I would prefer to see action at the state or federal level, rather than a patchwork of local statutes, however we learned with smoking bans that a rising groundswell can be an effective beginning. And like smoking bans, it need not be a competitive disadvantage. Certainly I would preferentially patronize restaurants that promise me a trans-fat free dinner!
Pontifex said,
May 16, 2007 at 4:58 pm
[[My apologies for editing a comment, but given the length I felt it would be most straightforward to address these points in context. -V]]
Trans fat alarmists would have you believe that these transient blood chemistry changes increase your chances of having a heart attack. The available scientific data, however, don’t back up that assertion. A number of studies of human populations have attempted to statistically associate consumption of trans fats with increased heart attack risk, but the only conclusion that can be fairly drawn from any of them is that, if there is a risk, it’s too small to measure through standard epidemiologic methodology.
[[Please review
Dr. Frank Hu’s article in the 1997 New England Journal of Medicine. This is an exceptionally rigorous study that demonstrates a strong result in a large study group. The lead author is highly intelligent, independent, and honest. If you care to critique his methodology, please offer specifics?]]
One of the major challenges for researchers is to tease out the potential impacts of trans fats from other dietary, lifestyle and genetic factors that might be relevant to heart disease. So far, it’s been an impossible task.
[[It is standard epidemiological practice to address known risk factors. In this case the most significant would be things like body mass index and overall caloric intake. Factors such as genetics presumably have at most a weak association with the independent variable.]]
The failure of human studies to support the alarmism was amply illustrated a few years ago when the National Academy of Sciences’ Institute of Medicine (IOM) jumped on the trans fat alarmist bandwagon. While touting studies showing that trans fats temporarily altered blood chemistry, the IOM glaringly did not cite any studies showing that trans fats posed any real risk to real people.
Despite the absence of real world evidence that trans fats are dangerous, the alarmism continues. There are at least two explanations for this phenomenon.
[[The endpoint in Dr. Hu’s study is actual heart attacks, not altered blood chemistry.]]
First, it’s been clear to the dietary research community for years – although they’ve been reluctant to share this information with the public – that the scare over dietary fat intake has been over-hyped. The final nail in the coffin of dietary fat hysteria came earlier this year when a major study concluded that low-fat diets provide no demonstrable health benefits over high-fat diets. So the trans fat scare constitutes a whole new way for researchers to scare the public about fat and to keep their government grants coming.
[[This is an exceptionally cynical world-view. Do you truly believe all researchers to be self-serving demagogues? Furthermore, if you research the history carefully, I believe you will find that the low-fat scare was perpetrated by the food industry notby the scientific community. The essential advice has changed very little over the years, however there is little profit in selling fresh fruit and vegetables, whole grains, and minimally processed food. The industry would rather have you believe that the latest low-fat low-carb psuedo-snack-energy-bar is somehow going to replace real food.]]
Second, the trans fat scare is a great new rationale for food manufacturers to introduce new and, perhaps, more expensive products that they market as “good for you.” Food companies learned long ago that there’s more profit in reformulating and marketing new and “healthier” products rather than trying to fight the bad science wielded by the well-funded, well-entrenched and essentially unaccountable public health bureaucracy.
[[I think you will find that there is less profit in this advice than in those earlier fads that the manufacturers promulgated.]]
Of course, the trans fat scare doesn’t work for every company in the food industry. Some can’t reformulate. Several years ago due to pressure from CSPI, McDonald’s announced that it would switch cooking oils to eliminate trans fats. But CSPI wound up suing the company after McDonalds could not find a substitute cooking oil that met its standards.
[[I agree this is a problem, though surely one we have the technology to solve? Look up what you can find on
1% linolenic acid soybean oil. It is not currently widely available, however it holds promise as a fry oil if you can believe what is said.]]
[[Apparently McDonalds has found
a substitute. No details, of course.]
There are two other facts to consider as you are bombarded with media reports and food company advertising about the alleged dangers of trans fats.
Thirty years ago, the diet police scared us away from animal fat-based butter and began singing the praises of what they said was a healthier alternative, trans fat-based margarine. Now, the diet police have done an about-face and want to scare us away from those same trans fats – all the while omitting mention that their butter scare was bogus from the get-go.
So what exactly would be the basis for trusting the alarmists this time around?
[[Read the study. Review the methodology. Then you tell me. Skepticism is healthy, but only if you back it up with knowledge and research. Unadulterated skepticism will lead you astray just as often as blind trust.]]
Also worth considering is the fact that CSPI has been in the business of scaring people about the food they eat for more than 30 years. From labeling Fettucine Alfredo as “heart attack on a plate” to claiming that fat substitute olestra might make truck drivers sick enough to lose control of their vehicles while driving, to claiming caffeinated beverages cause miscarriages, CSPI has been and remains on the cutting edge of dietary absurdity.
[[Who is CSPI? What research studies do they perform? What scientific journals do they publish in? I am an environmentalist as well, however that does not make me a supporter of Greenpeace.]]
Pontifex said,
May 16, 2007 at 8:00 pm
You know what, that was a bit snarky, My apologies, and a h/t to junkscience.com. What I more seriously consider is that municpalities stop trying to legislate behavior. The information about trans-fats is out there; let the consumer decide where they’d like to eat.
Valentine said,
May 16, 2007 at 10:28 pm
“What I more seriously consider is that municipalities stop trying to legislate behavior. The information about trans-fats is out there; let the consumer decide where they’d like to eat.”
This is not entirely accurate. Unless the restaurant voluntarily lists the nutrition facts for their menu, you don’t know what you are eating.
Note also the catch-22. Restaurants use trans-fats because they have no widely available alternatives. There are no widely available alternatives because restaurants don’t order them. A governmental mandate may be necessary to break this deadlock.
Pontifex said,
May 16, 2007 at 11:13 pm
But why? Why the insistence that government make *any* decision regarding my diet? Remember, the government here, according to the original documents, exists to perform *my* dictates, not the other way around.
If I want to butter my cheese, so be it. If I want to open a restaurant that serves said buttered cheese with a side of palm-oil fritatas, that’s up to me. Whether I will have a clientele is up to the clientele.
Let’s have fewer “governmental mandates.” Sounds a little totalitarian to me. Remember, we’re talking *food.* Next stop… where now?
Steve said,
May 17, 2007 at 3:02 pm
In my mind, publishing more information will allow the consumer to make their own decisions and vote with their wallet, as it were. The government already mandates the publishing of the TransFat quantity on purchased goods (as it does for Cholesterol level, fiber, et cetera), which certainly helps me direct my buying habits into a more healthy direction, at least by my perceived definition of healthy. I let my wallet vote for me, as it were.
What we are trying to balance is the following competing items:
– it is in the people’s interest (hence, government’s control) to encourage healthy behaviors through publishing health information. this is good for the nation in terms of its long-term health as well as its limited resource utilization (ERs, health facilities, doctors, public health costs such as MediCare, et cetera). it also provides consumers with more information in order to make better (by their own localized definition) purchasing decisions.
– it is intrusive and expensive (and hard to enforce) the publishing of (which?) health information for all restaurants, food producers, et cetera. the recently gutted FDA barely has the bandwidth to enforce existing food cleanliness and safety guidelines.
it is a tough problem, but i’d lean more on the side of the former and not the latter. even from a strict economic reason (and not for health/moral reasons), i suspect it would be cheaper to the nation to do so.
If we consumers could encourage (since a govt. mandate might be initially quite difficult to calculate, let alone enforce) restaurants to publish metrics information about their menus
This is the classic for-against seatbelt enforcement argument, of course. Or motorcycle-helmet-wearing. Or …
Valentine said,
May 18, 2007 at 1:23 pm
As far as I can tell, trans-fat free soybean oil is not even AVAILABLE right now, at least not on a sufficiently large scale to supply chains. If the NYC mandate sticks, these products will be introduced into mainstream distribution channels within the next year.
Michael Byrnes said,
May 31, 2007 at 9:55 am
“But why? Why the insistence that government make *any* decision regarding my diet? Remember, the government here, according to the original documents, exists to perform *my* dictates, not the other way around.”
Because *not* doing so would cost the government, and thus the taxpayers, more money?