Short Articles on Weight Loss

Why You Still Need to Eat Some Fat, Carbohydrate, & Protein Even When Dieting

It's the kind of fat, carbs, & protein that makes the difference.

When losing weight, we are really trying to manage food energy to make sure we burn a lot of stored fat in addition to whatever energy we get from food.  In practice, burning stored fat means eating less food energy (Calories) -- and that requires managing fat, carbohydrate, and protein.

But paradoxically, in order to be able to successfully eat less energy from food, you still have to continue to eat the right amounts of the right types of protein, carbohydrate, and even fat.

Why is this?

The short answer is because stored fat is not a perfect substitute for food, or even for just the energy from food.

What does that mean?

In theory, a Calorie is a Calorie, whether it comes from stored fat or from food you just ate. This theory is true, but it usually leads even nutrition professionals to make untrue assumptions that also make weight loss nearly impossible.

Food energy comes in three main forms: fat, carbohydrate, and protein. (For simplicity, we leave out alcohol, which we discuss elsewhere.)

But to your body, each of these forms -- fat, carbohydrate, and protein -- has a critical second purpose besides providing energy -- and stored fat cannot substitute for this second purpose.

This is one of the most important misunderstood reasons for the failure of most diets.  (There are simple ways to handle it successfully, but they are not obvious until you understand the issues.)

Protein

Most people know that "protein" is "structural" -- it can be "burnt" for energy, but it's main purpose is to build & repair tissues. When it is used for building & repair it cannot be used for energy, and when it is used for energy it cannot be used for building and repair  (kind of like wood).

This means that when dieting you need to eat a small amount of the right type of protein regularly because stored fat cannot substitute for this "building & maintenance" function of protein.

If your body doesn't get enough protein for its maintenance and repair needs, it is likely to trigger hunger, cravings, aches, pains, low energy levels, and other unpleasant symptoms as a signal that you need to eat to get it some more. These are exactly the symptoms that make diets so difficult. Most other unmet nutrient needs (e.g. vitamins and minerals) will also trigger one or more of these symptoms.

Fat

Most people do not know that some kinds of fat are also "structural" -- they are required for tissue building and repair  (and cannot be used this way if they are burned).  Stored fat in general cannot provide for this building/maintenance purpose -- unless it happens to be exactly the right kind of stored fat  (which is unlikely in most cases).

These "structural" fats are called the "essential fatty acids" (EFAs). There are two of them and the approximate amounts your body needs daily are well known.  Unmet EFA needs also tend to trigger hunger, cravings, aches, pains, and low energy levels, which naturally make dieting difficult or unsuccessful.

There are simple ways to handle this, but you need to understand the above concept before you can successfully use them.

(It is interesting to note that you could be a hundred pounds overweight, for example, and still be "starving" for one of the EFAs -- if your hundred pounds of excess fat was the wrong type of fat and had no EFAs.)

Carbohydrate

What about carbohydrate? Isn't carbohydrate used only for energy?

That's true, (with a few insignificant exceptions) but stored fat still cannot substitute entirely for carbohydrate.

Certain tissues  (mainly certain blood cells)  cannot use fat for energy under any circumstances. They will die without glucose (the main biological form of carbohydrate). And the brain and nervous system strongly "prefer" glucose for energy. Although the brain and nervous system can, after a time, "switch over" to using the ketone bodies from incomplete fat metabolism for energy, it is reasonable to assume that the brain is at least "inefficient" when forced to use ketones for energy.

Whenever this happens, you will experience one of two very unpleasant sets of symptoms usually referred to respectively as "hypoglycemia" and "ketosis".  And you also typically feel some combination of hunger, cravings, aches, pains, and low energy levels.

How much protein, fat, and carbohydrate do you really need?

Protein: In general, you can minimize or eliminate unpleasant symptoms by eating food with about 100 grams of (high-quality) protein per day. This will be enough under almost all normal circumstances. And it will not be so much that your body must burn  an excess instead of using it for structural purposes.

Carbohydrate: In general, 100 grams of carbohydrate per day is about the minimum that will prevent symptoms like hunger & cravings. (The brain and nervous system are considered to need about 130 grams per day.) However, your body uses carbohydrate at a very variable rate, so on some days this may not be enough.  On a busy day you will use more than this; on a slow day 100 g will be sufficient. (There are other situations that can cause a higher requirement -- carbohydrate needs are difficult to predict.)

EFAs: In general, you need about 2 grams per day of the EFA called "alpha-linolenic acid (ALA), and you need about 10 grams per day of the EFA called "linoleic acid" (LA). These amounts are likely to be enough under almost all normal circumstances.

How can you find out what foods have the right amounts of the right kinds of protein, carbohydrate, & fat? There are three ways:

1. Read the other articles on this site  (mainly in the protein, EFA, and carbohydrate sections).
2. Buy the book we publish -- The Multi-Diet -- from your local bookstore. (This is the easiest and most complete way to understand all of the issues dieters face.)
3. Buy one or more of the short eBooks we provide on this site. (These are the fastest way to get started, but don't provide all of the detail that's in The Multi-Diet print version.)