After bariatric surgery, fat acts like a lubricant in food. It helps the food go down easier and decreases the chance of the food feeling like it is “stuck”. But there are two important aspects to the fat in your diet after bariatric surgery. One is the quantity of fat and the other is the quality of the fat. Fat slows down digestion, which may make you feel like the food is “just sitting there” after eating a meal higher in fat. Also, some people experience symptoms similar to “dumping” when consuming fried foods after surgery. The type of fat consumed is important in terms of health but also tolerance due to changes in taste acuity after surgery.

Small amounts of some fats are beneficial. There are four types of fats in the food we consume: saturated fat, polyunsaturated fat, monounsaturated fat, and trans fat. All these fats have a different effect on the body.

Saturated Fats
These fats are higher in fatty meats, fat-containing dairy products, palm and coconut oils, and tend to contribute to LDL (bad) cholesterol levels. As a rule, the more saturated fatty acids in a fat the harder its consistency at room temperature and the more damaging it is to your health. Take a piece of steak with a lot of visible fat on it out of the refrigerator and let it stand at room temperature. The fat on the outside remains in a solid form. That mean it’s primarily made up of saturated fat.

Monounsaturated Fats
These fats are liquids at room temperature but will start to become solid when refrigerated. For instance if you make a salad dressing using olive oil and put it in the refrigerator, when you remove it, it will appear much thicker, almost solid. So you know this primarily a monounsaturated fat. Monounsaturated fats can be found in canola, olive, almond, and peanuts oils, and seem to have the effect of lowering LDL cholesterol without lowering protective HDL cholesterol.

Polyunsaturated Fats
These fats are found in corn, soybean, safflower, and sunflower oils. They are liquid at room temperature and remain liquid when refrigerated. Again, if you make a salad dressing with one of these oils and refrigerate it, it will be liquid when you remove it. Polyunsaturated fats may lower LDL levels but they may, if used in large enough quantities, reduce HDL cholesterol levels as well.

Trans Fatty Acids
Trans fatty acids is a term you may have heard but aren’t sure what they are. These are fats that occur naturally in small quantities in red meat and dairy fats, but for the most part they are created. For example, to make crackers or cookies, the manufacturer needs oil. But if liquid oil is used the recipes don’t turn out properly so the manufacturer chemically changes the liquid by adding “hydrogen” to it. This causes the oil to become hard, which allows the cookies or crackers to turn out properly. The problem is that the harder oil is now a different product called “hydrogenated”, a word you can see on ingredient labels. Hydrogenated fats, or trans fats, act like saturated fats. Trans fats raise LDL cholesterol and lower HDL cholesterol.

Effective January 1, 2006, the FDA will require trans fats to be listed on nutrition labels so you’ll be able to tell at a glance if the fat is good fat that’s been turned bad, and in what quantity. If trans fat is not on the label, take a look at the ingredients list. If you see the words, “hydrogenated” or “partially hydrogenated” oils as one of the primary ingredients – beware.

Sterols and Stanols
Sterols are natural components found in soybean, and stanols come from other plant sources. Because sterols and stanols are structurally similar to cholesterol, they compete with cholesterol for absorption into the body. The result is that plant sterols and stanols interfere with your body’s ability to absorb cholesterol, lowering LDL cholesterol. Scientists began to learn about the benefits of plant sterols as far back as the 1950’s, but they have only recently been incorporated into food products available in the grocery stores.

Even if you are already eating a diet low in cholesterol, your blood cholesterol level can still be lowered significantly by introducing sterols and stanols into the diet. The amount of plant sterols and stanols needed for significant cholesterol lowering to take place is a minimum of 1.3 grams per day. Normal amounts of plant-based foods in the average diet provide only about 300 mg a day, and this is not enough to significantly lower cholesterol.

Margarine spreads fortified with plant stanols and sterols are the most effective way of getting plant sterols/stanols into your diet. In addition, new sterols/stanol-containing food sources are being introduced into the market, which will make it easier to eat the recommended daily amount.

Research has shown that LDL cholesterol can be lowered by 10% to 15% if 2 to 3 grams of sterols/stanols are incorporated into the daily diet. In most stanol/sterol spreads one serving contains 1.7 grams of plant sterol esters. To get maximum effect, 2 to 3 servings should be eaten daily (1 serving is 1 tablespoon).

Let’s Get Nuts
Nuts are usually tolerated very well after bariatric surgery – they are easy to chew well and easy to digest. Nuts are ok, as part of a meal and in moderation. Although nuts contain some protein, most of the calories in nuts come from fat. People often mistakenly count a serving of nuts are either a serving of protein or carbohydrate. A serving of nuts is equal to a serving of fat.

In 2003, the FDA announced it would allow certain nuts to make a qualified heart-health claim on their package. Specifically, it would allow the following claim on packages of whole or chopped peanuts, almonds, hazelnuts, pistachios, walnuts and pecans:

“Scientific evidence suggests but does not prove that eating 1.5 ounces per day of most nuts, as part of a diet low in saturated fat and cholesterol and not resulting in increased caloric intake may reduce the risk of coronary heart disease. See nutrition information for Fat Content.”
This claim does not apply to cashews, macadamia nuts, Brazil nuts or pine nuts. Because nuts are calorie dense, it’s important to eat nuts as a replacement for foods containing higher amounts of saturated fat without increasing the total number of calories you regularly consume.

Depending on the type, nuts also provide a variety of vitamins and minerals. For instance, almonds are an excellent source of fiber, vitamin E, manganese and magnesium, and a good source of riboflavin, phosphorus and copper. Similarly, cashews are a good source of iron, phosphorus and zinc, and an excellent source of magnesium, copper and manganese. Walnuts contain omega-3 fatty acids and other antioxidants that have been shown to have cholesterol lowering benefits. And the dependable peanut provides a good source of vitamin E, fiber, phosphorus and magnesium, and an excellent source of niacin and manganese, all in addition to promoting heart health.

Fats or Fiber For Satiety?
Let’s take a look at how fat and fiber compare in terms of making you feel full and satisfying appetite.

Fat is extremely pleasing to the brain. A fatty meal or snack is especially dangerous in the presence of hunger. The mind searches for relief from it’s discomfort – hunger. Fatty foods are likely to be chosen to soothe hunger because they signal the brain with such pleasure.

Fatty foods are calorie dense. Time and again it has been shown that when hunger leads you to fatty foods, you are likely to overshoot your needs by lots of calories. High-fat foods taste good and get swallowed so easily that you can eat too fast, way beyond energy balance.

Fat has only a weak effect on satiety. Compared to carbohydrates, fat is slower to make you feel full. That means the timing to eat again is not pushed back. So you don’t compensate for the excess fat calories at one meal by eating fewer calories at a later meal.

Carbohydrates satisfy appetite faster and longer. A key difference between carbohydrate-rich plant foods and fatty foods is the latter have no fiber. Compared to fat, the fiber in plant foods makes you feel full sooner. Fruits, vegetables and legumes create a noticeable desire to end the eating event and stretch the time between meals in your favor, both working against weight gain.

The body adapts to eating fat. Another factor is that hormones reactive to the intake of fat work against weight management if meals are always loaded with fat calories. As you continue to eat fatty foods, the stomach receptors for the satiating hormone cholecystokinin (CCK) decrease in number. This hormone is a key to feeling stuffed. With adaptation to less active CCK, the stomach empties faster and you are able to eat more. The more fat you eat, the more you can comfortably eat.

These characteristics of fat lead a person to eat more frequently, eat more calories with each bite, and to eat more bites. Fat-sugar or fat-salt combinations in particular create a reward that can easily override nature’s signal to stop eating.

Complex carbohydrates convert to relatively little body fat. The hypothesis that excess carbohydrate calories convert into fat can be dismissed. Biochemists confirm that this pathway has an insignificant role in the accumulation of body fat. This does not mean, however, that carbohydrate calories don’t count. If you binge on carbohydrates, very little fat is burned and most of the fat you eat moves directly into fat storage sites.

A substantial and growing body of research suggests that the most effective approach to permanent weight loss is a food plan consisting primarily of whole, unrefined grains, vegetables, legumes, and fruits in the amount and frequency to satisfy appetite.