Low Fat Diets

Low fat diets and weight control

There are several reasons why a low fat diet (20-30% of total calories) is the best diet to follow for losing weight and maintaining a healthy body:

Although any diet that is reduced in calories will cause weight loss, a low fat diet has been found to be the best choice for weight maintenance. If you follow a low fat diet to lose weight, you don’t need to learn new eating habits to maintain the weight you lost – you’re already doing what you need to do.
Low fat diets are low in caloric density. In other words, a low fat diet contains foods that are bulky and filling like whole grains, fruits, and vegetables. So, you can eat a greater quantity of these foods because they have a lower caloric value than foods containing a lot of fat. Just compare 200 Calories worth of celery versus eating 200 Calories worth of potato chips! A lower fat diet looks and feels like a lot of food, which can be satisfying, and this helps with weight control.
Last, and most important, is the fact that a low fat diet is the best choice for lowering risk of heart disease, diabetes, and certain cancers – the killer diseases. It is a therapeutic diet as well as preventive – if you’re not following a lower fat diet now, chances are eventually you will be advised to do so by a physician because the common risk factors for heart disease and diabetes are so prevalent. A low fat diet really is a diet for life.

How Low Can You Go?
If your diet is too low in fat, it can become quite tasteless, boring, and difficult to eat. In addition, you need at least 3% of your calories as essential fat, the fats your body can’t make on its own. Unless there is a medical need, going below 20% of calories as fat won’t add much benefit and takes away from the pleasure and taste of food. For most people, 25-30% of calories as fat is a very good goal. This is why most of the diets I plan have this composition. But, not all fat is alike! Read on…

Fats: Not Created Equal!
Although all fats have the same number of calories per gram (9 calories per gram, the most calorically dense nutrient), the type of fats you choose make a huge difference in the effect upon the body. All fats are either converted to fuel, or if they are extra calories, will be converted to body fat as a form of storage energy. But in the process, different fats have a profoundly different effect on the arteries. This is why your diet plan is carefully balanced, so that a majority of your fat comes from “good” fat, and so that you don’t get too much “bad” fat, the kind that contributes to heart disease, high blood pressure, and atherosclerosis.

To make things simple, you can think of all types of food fat fitting into three categories:

Saturated fat: these are hard fats like shortening, coconut oil, palm oil, cocoa butter (fat in chocolate) and animal fats like lard, butter, dairy fat, the fat in the skin of poultry or between the muscle of animals like steak fat. Anything made with these fats (like store-bought baked goods, cookies, crackers, etc.) are sources of saturated fat as well. There is no question now that these types of fats are linked to the formation of plaque (the stuff that blocks coronary arteries) and contribute to heart attacks. Whether you are trying to lose weight or not, your diet should contain LESS than 10% of calories as saturated fat. For example, for people who need 2000 Calories a day, this translates to about 20 grams of this type of fat a day. If you are following a reduced calorie plan and your calorie needs are 1400, the saturated fat should be only 15 grams or less per day. If you are at high risk for heart disease, you should eat even less saturated fat, 7% of calories rather than 10%.

Use this information to evaluate the healthfulness of a food. Read the label, clearly if a dessert has 10 grams of saturated fat per serving, you’re going to need to really avoid other sources of saturated fat throughout the day to meet this health goal. Butter has about 7 grams of saturated fat in one tablespoon!

Your eating guidelines are designed to keep the saturated fat low in your diet. Choose very lean meats, low-fat and fat-free dairy products, and avoid hard spreads like butter and stick margarine.

Monounsaturated Fats: In a heart healthy diet, these fats used to be considered kind of neutral, not bad, but not great either. Now these fats are the preferred fats to use, because they have been found to lower LDL (low-density lipoprotein – the bad cholesterol) and raise HDL levels – (high-density lipoproteins – the “good” cholesterol). Good sources of monounsaturated fat include olive oil, Canola oil and Canola soft margarine, as well as salad dressings made from these fats. Other sources are avocados, olives, peanut oil, and nuts like cashews, macadamia, and pistachios.

This is why it is recommended that you include mostly olive oil or Canola oil when cooking or baking with fat. Most commercially produced foods do not use these fats, a good reason to try and cook from “scratch” whenever possible!

Polyunsaturated Fats: These are fats that are liquid at room temperature and are mostly of vegetable origin. Most vegetable oils like corn, safflower, and seed oils like cottonseed are polyunsaturated. Margarine and salad dressings made from these fats are a good source of polyunsaturated fat as well. These are also “good” fats, but they do not have a desirable effect upon HDL levels like monounsaturated fats. Include some of these types of fats in your diet as a good source of essential fatty acids, but use more of the monounsaturated fats when you have control over the type of fat in cooking.

To summarize, eating less fat (25-30% of calories for most people) is a key nutritional goal. This means controlling the amount of fatty foods and fat spreads, and following your eating guidelines for your particular amounts. Beyond that, get smart about the types of fats you choose – it’s easy to find “good” fats, and it will make a big difference to your arteries.

This article on fats is just an introduction, and is simplified to get us thinking about the two basic concepts of eating right: eat less fat, and choose the right type of fats. Other issues, like “trans fatty acids” and “omega-3 fatty acids” are important topics, and are addressed in our member's only support center.