Not All Fats are Bad Fats

 

I have a confession: I love butter. In fact, I would say it’s on my favorite foods list, right up there with nuts and chocolate. But I also love extra virgin olive oil and avocados, and this amazing toasted walnut oil. Fat is satisfying, it makes food taste better and keeps us fuller longer, stabilizing blood sugar. It is soothing and nourishing, and when consumed in moderation, is a necessary component of our daily diet.

To begin, let’s have a quick lesson in “Fats 101″:

Fat is a macronutrient, just like protein and carbohydrate and something our bodies need. Fats are precursors to hormones, they cushion our internal organs, they regulate our temperature, and they carry fat-soluble nutrients through our bodies. As part of a balanced diet, we need a variety of natural fats.

 

So, how much is too much? That depends on the person. The standard advice is to limit fats to no more than 30% of calories in one’s daily diet. In my experience, what feels right varies from person to person. For example, some people feel better with 20 to 25% fat, while others need a bit more, perhaps 35 to 40% – more along the lines of a Mediterranean-style diet. If you crave a lot of sugar and feel hungry within just a couple of hours after eating, your body may need a little bit more fat. Try adding a few slices of avocado to a meal, or rather than something sweet for dessert, have a small handful of nuts or a spoonful of a natural nut butter. My very favorite: roasted almond butter!

Here are the different types of fats:

Saturated Fats – these are solid at room temperature. They include animal fats (not fish!) such as butter, cream and cheese, and just a few plant-based fats: Coconut, cocoa, palm and palm kernel oils. While some authorities claim that saturated fat should be avoided, others say that these stable fats have been used around the world for thousands of years in their natural state. I personally believe that all natural fats, including saturated fat, can have a place in the diet. They are ideal for cooking in many instances because they are not easily damaged by heat.

Monounsaturated fats are liquid at room temperature and some (peanut and olive, for example) may harden when refrigerated. They are found in olive, canola, peanut and avocado, as well as high oleic sunflower and high oleic safflower oils (these are often called “high heat sunflower and high heat safflower” oil). Monounsaturated fats are recognized as highly beneficial: They help keep HDL cholesterol high and they are stable fats for cooking. When using olive oil, be sure to cook on low or medium low heat…olive oil has a low flash point so it burns quickly. You can also combine it with other oils such as canola or high heat sunflower oil for a milder flavor.

Polyunsaturated Fats - these are liquid at room temperature and liquid when refrigerated. You will find them in nuts, seeds, egg yolk, corn, soy and fish. (Polyunsaturateds contain those Essential Fatty Acids you hear about – I’ll do another post soon about all of that!) I never advise cooking with oils that are high in polyunsaturated fat. This is because they are easily damaged by light and heat and are best eaten in their original form such as edamame or corn, or used raw such as flaxseed oil or sunflower oil.

Trans fats – these are created when liquid oils such as soybean or cottonseed have been chemically treated in order to make them solid at room temperature. You may see the words “partially hydrogenated” on a food label – means the same as trans fats. These partially hydrogenated oils, commonly used by food manufacturers, are very unhealthy and should be avoided whenever possible. At Whole Foods Market, you don’t have to worry or read labels because we don’t allow man-made hydrogenated fats in the foods we sell. Common sources of trans fats include most commercial baked goods, processed foods, pie crusts, cookies, crackers and margarine. (FYI: we sell all-natural, good-tasting margarines that are created from natural oils such as palm and canola.)

Some of my favorite ways to add a variety of good fats to meals and snacks are:

• Add a couple tablespoons of chopped walnuts to breakfast cereal or yogurt
• Sprinkle a tablespoonful of pine nuts, sunflower seeds or pumpkin seeds on your salad
• Add ½ cup of chopped almonds, pecans or walnuts to a cookie or cake recipe, or sprinkle over the top
• When making stir-fry for dinner, add a handful of roasted cashews just before serving
• Top grilled fish or chicken with sliced avocado
• Drizzle extra virgin olive oil over sliced veggies such as cucumber, tomato or steamed veggies. (adds great flavor and extra virgin olive oil is filled with antioxidants and other plant compounds)
• Add chopped olives to tuna or chicken salad
• Put a pat of organic butter on your hot steamed veggies
• Sprinkle finely chopped macadamia nuts or hazelnuts over a bowl of berries
• Eat fish such as salmon, sardines, char or mahi-mahi 2 or 3 times a week
• Make your own buttery spread by mixing ½ cup olive oil and 1 stick softened butter in the blender. Puree until smooth then store in a container with a lid in the fridge – it becomes semi-solid like tub margarine, and is easily spreadable, and contains NO trans fats. Use raw or for cooking.

 

Why fast foods are bad, even in moderation

 

Eating a diet consisting largely of fast food could cause your waistline to bulge more than eating the same amount of fat from healthier sources.

Monkeys fed a diet rich in trans-fats – commonly found in fast foods – grew bigger bellies than those fed a diet rich in unsaturated fats, but containing the same overall number of calories. They also developed signs of insulin resistance, which is an early indicator of diabetes.

Trans-fats, or partially hydrogenated oils, are found in many fast foods and also in baked goods and processed snacks. They dramatically increase the risk of heart disease – even more than saturated fats found in animal products.

Kylie Kavanagh, at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina, US, wondered how this "killer fat" would affect the risk of diabetes in 51 vervet monkeys.

She fed one group of monkeys a diet where 8% of their daily calories came from trans-fats and another 27% came from other fats. This is comparable to people who eat a lot of fried food, says Kavanagh. A different group of monkeys was fed the same diet, but the trans-fats were substituted for mono-unsaturated fats, found in olive oil, for example.

Both groups ate the same total calories, which were carefully metered to be just enough for subsistence.

Path to diabetes

After six years on the diet, the trans-fat-fed monkeys had gained 7.2% of their body weight, compared to just 1.8% in the unsaturated group. CT scans also revealed that the trans-fat monkeys carried 30% more abdominal fat, which is risk factor for diabetes and heart disease.

"We were shocked. Despite all our enormous efforts to make sure they didn’t gain weight, they still did. And most of that weight ended up on their tummies," says Kavanagh, who presented her findings at the American Diabetes Association meeting in Washington DC, on Monday. "This is walking them straight down the path to diabetes."

This is the first study to show such a dramatic result on abdominal fat, adds Dariush Mozaffarian at the Harvard School of Public Health in Boston, US. "The days of thinking about fats just as calories are over," he says.

Partially hydrogenated oils can easily be replaced by other oils during food production. Last week, fast-food giant Wendy’s announced that it was cutting partially hydrogenated oils from its food in the US and Canada, while in January, food manufacturers in US were ordered to label all trans-fats on packaged goods.