The “F” Word

Diet Myths Debunked

FAT! There, I said it.

For years I feared this dreaded word. Trained that fats should be limited and always unsaturated, I was very choosy with what entered my mouth. Skim, low-fat, non-fat, 99% fat-free…the less fat, the more I ate.

FAT As We Know It

Fats have been blamed for many of the health problems plaguing Americans- obesity, heart disease, stroke, diabetes, cancer,… We’ve been taught that fats are either good or bad, and one false move could be hazardous to our health.

We know that fat is a necessary part of our diet, for things like: providing essential fatty-acids, skin health, cell membrane structure, and delivering fat-soluble vitamins. Some fatty acids even have anti-inflammatory properties, but despite these positive roles in our health we’ve been convinced that they should be mostly minimized.

Margarine: Wolf in Sheep’s Clothing

This supposed nutritional doctrine (fat bad, carb good) has been the precipice of an entire food industry. Lab-created, chemically derived “better than butter” spreads now dominate grocery store shelves. Before plant sterol spreads infused with omega-3s hit the market, margarine was the most popular butter substitute donning yellow dye #3.

It looked like, tasted like (sort of), melted like, and was healthier than butter thanks to its lower cholesterol content. Unlike bad butter’s animal origins, margarine was made from vegetable oils (and what could be more healthy than vegetables, right?). The problem was, that in order to get these liquid-at-room-temperature soybean, corn, and cottonseed oils into a creamy, solid spread, scientists had to add hydrogen atoms to their fatty acids. (Caution: Geeky science speak ahead! Feel free to skip to the end of this section where I conclude that margarine is the root of all evil).

Food manufacturers sneak in trans fats without having to label them. They are only required to list >0.5 g trans fat per serving. Always check the ingredient list. Photo courtesy The CDC.

Food manufacturers sneak in trans fats without having to label them. They are only required to list >0.5 g trans fat per serving. Always check the ingredient list. Photo courtesy The CDC.

Partial hydrogenation, as in Crisco and margarine, causes some of the double bonds in an unsaturated oil to be changed into single bonds. Naturally occurring double bonds are in the cis formation (we’ll call this one the innocuous structure), whereas the trans formation is favored during the process of partial hydrogenation.

When the body is busy digesting trans fatty acids its digestion of essential fatty acids (like omega-3’s and omega-6’s) is inhibited. This is why trans fats have been found to: increase bad LDL cholesterol, decrease good HDL cholesterol, increase triglycerides and start an inflammatory response throughout the body.

trans-fat and the body

And it turns out that scientists have connected trans fats to problems like cardiovascular disease since the 1950s. (Let me let that sink in. Conspiracy much?)

The Red Herring of Food Industry Fat

We’ve spent the past six decades trying to figure out how countries like France, Germany and Switzerland can have diets high in butter and cheese and continue to have lower incidence of heart disease than the western world. What if there’s more to the story than we’ve been taught for the past 60 years? A growing body of research has found that eating a moderate amount of saturated fat can reduces the risk of Type 2 Diabetes and reduce blood pressure as well as blood sugar. British scientists looked at the diet of half a million subjects and concluded “Saturated fats do not cause heart disease”. Saturated fat raises HDL cholesterol (the good kind) more than any other food compound, so some argue that even though it raises the “bad” cholesterol, it has no effect on heart disease risk. What’s more, popular oils like canola, soybean, and olive oil can produce lipid peroxides and aldehydes (read “CANCER”) when cooked at high heat. This is because those wonderful double bonds that are so good for our hearts end up combusting when heated, whereas saturated fats like coconut oil, butter, and lard are more stable.  Like so many nutrition “truths” out there, the vehement demonization of saturated fats has once again come into question.

Bottom [waist]Line on Fat

All of this is not to give one vindication to gorge on peanut butter and ice cream, but there are some great take away points:

  1. Not all fat is bad. When choosing fat, omega-3’s are great, omega-6’s are good, and some saturated fat is okay. Saturated fat from avocado, raw coconut oil, hormone-free, antibiotic-free grass-fed beef, pastured pork and free-range chicken (and their eggs), and milk, cheese, and butter from grass-fed beef are the best options.
  2. Trans fats are all bad, and should be avoided at all costs. Hey, you’ll be doing yourself a huge favor by getting rid of all that processed junk you’ve been gnashing on.
  3. How fat’s been processed and how you use it matters. Look for cold-pressed or expeller-pressed oils that have minimal processing e.g. bleaching and deodorizing. Use your canola and EVOO in dressings and leave high-heat sautéing and frying to the saturated pros (or peanut oil if you don’t have an allergy).
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