An Interview With The Big Fat Surprise Author Nina Teicholz

Tricia Ward, Nina Teicholz


February 09, 2015 | Medscape Cardiology: Proponents of the low-fat diet (the Dean Ornishes of the world) argue that studies like PREDIMED[10] didn't really test a low-fat diet because subjects didn't reduce their fat consumption enough.[11]

Ms Teicholz: That's revisionist thinking. Since the 1970s and for the past four decades, the low-fat diet has been defined by the American Heart Association as somewhere between 25% and 35% fat, around 30% on average. That's the official low-fat diet. That clearly hasn't worked. Now there are folks like Dean Ornish and some of the vegan proponents who say that's not really a low-fat diet and propose something even lower, called the very–low-fat diet. The very–low-fat diet has simply not been well tested. Dean Ornish has done one study on 22 men.[12] It was multifactorial, with stress reduction, exercise, and all kinds of interventions. You really don't know what is attributable to diet. The other experiments have been uncontrolled, not randomized. I don't know what you could say about the very–low-fat diet except that there are hardly any data on it. | Medscape Cardiology: Moving back to trans fat, you have a chapter in the book regarding the potential US Food and Drug Administration ban on trans fat (some cities have already banned them) because you are concerned with what we might get as a replacement.

Ms Teicholz: Nobody has looked at the issue of what replaces trans fats. It hasn't been part of the conversation, which in itself is an amazing oversight. If you're engaging in policy, you need to know what the trade-offs are. Getting rid of partially hydrogenated vegetable oils is probably one of the biggest food shifts in the country over the past two decades. There are billions of pounds of vegetable oil in the food supply every year. You have to look at what's going to replace trans fats. The reason we got trans fats is that oils are not stable, so you have to manipulate the oil in some way to give it stability. Partially hydrogenating oil gave it stability so it wouldn't go rancid. It gave it a more solid, stable form. One of the side effects is that it produced trans fats.

There are a number of specialty oils that have been engineered to be more stable. There are oils made from genetically bred soybean seeds that produce different kinds of fatty acids. The manufacturers do something called interesterification. Those specialty oils are quite expensive and are still in short supply. In frying operations in major fast food chains all across the country, they mainly use peanut, soy, and corn oil. Those oils have the same problem in that they're not stable, especially when they're heated over long periods of time, as typically occurs in restaurant fryers. They produce literally hundreds of toxic oxidation products. Some of the worst are aldehydes. They are extremely worrisome. I believe my book is the first time anybody has pulled together all of the data from numerous fields to make the case that these oxidation products are worrisome to human health. If you're going to get rid of trans fats, you need to know if you are jumping out of the pan into the fire, so to speak. | Medscape Cardiology: Trans fat came into the food chain largely because of the move away from frying in lard.

Ms Teicholz: We got started down this road because scientists decided that we shouldn't eat saturated fats. Saturated fats are naturally stable. They don't oxidize even when they're heated at high temperatures. That's one of the unsung virtues of saturated fat. They're naturally stable. McDonald's used to fry their french fries in tallow. Tallow and lard are very stable fats.


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