This series reviews Dean Ornish’s evidence-based claims of healing & disease reversal by dietary and lifestyle changes. He is a California University Professor of Medicine in San Francisco. This instalment discusses “bad” fats.
Trans-fatty acids, partially hydrogenated fats and saturated fats (“bad fats”) should be avoided. Many food manufacturers continue to use them because they increase their products’ shelf-life, even though they may decrease the “shelf-life” of the people who consume them.
Saturated fats are found mainly in animal fats – in meats (including chicken and other poultry), full-fat dairy produce (milk, cream, cheese and ice-cream), egg yolk and (to a lesser extent) seafood. Some plant foods, such as coconut and palm oils, are also rich in saturated fats.
When vegetable oils are heated in the presence of hydrogen, both partially hydrogenate and trans-fatty acids are produced. Partially hydrogenated fats are as disease-promoting as saturated fats.
Trans-fatty acids are especially bad for health. They are found predominantly in commercially prepared baked foods, margarines, snacks, fast foods, processed and fried foods. Trans-fatty acids are probably worse for cholesterol levels than saturated fats because they raise bad LDL and lower good HDL. It’s wise to avoid both saturated fats and trans-fatty acids.
Besides raising total and LDL cholesterol levels, saturated, partially hydrogenated fats and trans-fatty acids promote inflammation and are strongly linked with increased risk of coronary heart disease, stroke, diabetes, many types of cancer, and other chronic diseases.
A recent scientific presentation1 also claimed that diets rich in trans-fatty acids may cause a redistribution of fatty tissue to the abdomen (the worst place to store fat for both health and appearance) and lead to a higher body weight, even when total calorie intake is the same.
Processed food labels now list both saturated and trans-fatty acids. Also, the more hydrogenated an oil is, the harder it will be at room temperature. Soft tub margarines usually have less hydrogenated fats and trans-fatty acids than harder margarines that come in bars.
Professor Ornish began consulting with McDonald’s in 1999, to help them develop more healthy foods. His first recommendation was to remove trans-fatty acids from their products. This was quite a challenge for McDonald’s to preserve the flavour and texture of its French fries, but they found a way to do it. He then helped them develop a Fruit & Walnut Salad, containing apple, grapes, walnuts and low-fat yogurt – McDonald’s is now the largest purchaser of apples in the world. He also helped them develop an Asian Salad, containing sixteen types of greens, soybeans, almonds, mandarin oranges, peas and red bell peppers.
He has also helped PepsiCo and Safeway Supermarkets … when making more healthy foods becomes good business, it becomes sustainable. At PepsiCo, for example, more than two thirds of revenue growth now comes from its good-for-you and better-for-you products.
It takes time for companies of this size to change their product range to include more healthy foods, but Prof Ornish feels it’s happening more quickly than he expected, and is proud of the impact it’s having worldwide in making healthy eating more convenient and fun.
- Rudel LL, Kavanagh K. Tran-fat leads to weight gain even on same total calories. The 66th Annual Scientific Sessions of the American Diabetes Association, Washington, DC, 2006.