The Truth About Fats
The quick answer: No food group is more incorrectly understood by the public than fat. For best health, avoid refined (especially hydrogenated) oils, in favor of traditional fats (olive oil, butter, lard, etc.).
The 2nd Deadly Trend
Last week we focused on the 1st of seven deadly changes to our food—the rise of sugar from an occasional treat to America’s biggest source of calories. Sugar is the #1 additive in processed foods.
This week we discuss the 2nd deadly change: factory fats, beginning with vegetable oil hydrogenation. To explain, here are seven common hydrogenation and trans fat facts:
- Why were refined oils (corn oil, soybean oil, etc.) hydrogenated? Hydrogenation extends shelf life. An unnaturally long shelf life is good for the food business but generally bad for our health.
- What causes short shelf life? Omega-3 oils—the ones needed for brain, eye, and nerve health, as well as fertility—after being processed, are highly reactive to oxygen. When oxidized these oils become rancid which spoils taste.
- How do you hydrogenate refined oil? The oils are heated and passed through a reaction chamber where they are exposed to hydrogen gas in the presence of a metallic catalyst. The hydrogen saturates the carbon atoms that form the backbone of the oil molecule. This thickens the oil and makes it much less reactive to oxygen, but also forms toxic trans fats.
- How bad are trans fats? They’re deadly. The Harvard School of Public Health (HSPH) is our leading academic center for nutrition. In 1994, Dr. Willett and others from HSPH published a paper in the American Journal of Public Health showing that trans fats cause between 30,000 and 100,000 deaths every year in the US. Trans fats are a risk factor for inflammation, diabetes, and heart disease.
- How did trans fats get into our diet? The first hydrogenated fat product was Crisco, introduced a century ago in 1911. Crisco was followed by margarine as a butter substitute during WWI. Vegetable oils, introduced later, were partially hydrogenated. Because processed foods depend on vegetable oils for mouth feel and taste, most processed foods contained trans fats.
- Are trans fats still allowed in food? Yes. As the public has become more informed about the toxicity of trans fats, the use of hydrogenation has declined, but Congress has not banned trans fats, though labeling was required in 2006. Denmark effectively banned trans fats in food in 2003, followed by Switzerland in 2008. New York and a few other cities restrict the use of trans fats by restaurants.
- Why do some processed foods claim “zero trans fats” but have hydrogenated oils in the ingredient list? Our federal government wrongly allows foods that contain less than 0.5 gram per serving to be labeled “zero trans fats.” This is shocking because the prestigious Institute of Medicine recommends we eat absolutely no trans fats.
The Power of A Woman
Dr. Mary Enig of the University of Maryland was the first to publicly warn of the toxic nature of trans fats. She also argued that trans fats were a cause of inflammation and heart disease. This claim was controversial as the public had been told saturated fat and cholesterol was the main cause. Enig pointed out that man had eaten saturated fats long before the rise of heart disease. She further noted that trans fat intake increased in step with heart disease while saturated fat intake actually declined as a percent of calories.
Dr. Enig took a lot of flak from the food industry but stood her ground—time has shown her to be right. For a better understanding of which fats are healthy, read her excellent book, Know Your Fats.
Dr Fred Kummerow, Enig’s colleague at the U. of Maryland, is also a feisty opponent of trans fats. In 2009, at the age of 94, he submitted a 3000-word petition to the FDA that began, “I request to ban trans fats from the American diet.” He publicly commented, “Everybody should read my petition because it will scare the hell out of them.” I called Dr. Kummerow this morning to see if the FDA had responded to his petition—as required within 180 days. I’ll share his response when it comes.
Deep Fat Frying
Deep fat frying is the ultimate test of cooking oil, as the oil sits for days at high temperatures, exposed to oxygen. In the past tallow was successfully used (thus the great taste of the early McDonald’s fries). When the public was falsely taught that saturated fats like tallow were unhealthy, the food industry converted to hydrogenated vegetable oils. Unfortunately, because of the trans fats, this was far unhealthier. Tragedies like this keep happening with Food Inc.
Deep fat frying thus remains the last major use of hydrogenated oils. To my knowledge, only In-N-Out has stopped, but problematic oxidation of fats from extended use at high temperature remains. I suspect the very last refuge for hydrogenated oil use will be the mom-and-pop donut shop.
The 2nd Healthy Change protects from toxic trans fats and other unhealthy stuff found in deep fat fryers:
This means no French fries, no donuts, no onion rings, no corn dogs, not even the toxic deep fried Twinkies or Snickers Bars at the county fair. Please note this does not eliminate deep fat frying for the home cook, using fresh and healthy oils. Better yet, check our recipe, for Oven-Roasted Fries. The recipe works with sweet potatoes or yams also.
In 13 weeks we’ll return to the subject of fats, discuss the importance of balancing omega-6 and omega-3 in the diet, and recommend the use of traditional fats over refined vegetable oils.
Pease comment: Share your experience with trans fats, or your recipe for home fried vegetables.