Short Articles on Weight Loss

Carbohydrate

Many people, even nutrition professionals, assume carbohydrate is "unimportant" for weight loss. They are wrong.

The conventional theory is that carbohydrate provides only an unnecessary form of energy, and that therefore dieters can eliminate carbohydrate from their diets in order to force their bodies to use more stored fat Calories for energy instead.

This is an attractive theory. It has elements of truth. But people who try various very low carbohydrate diets always find out that it doesn't really work that way. There is something else needed to connect the theory with the practice.

Here’s the missing link.

Glucose (the biological form of carbohydrate) is not theoretically an essential nutrient because your body can make enough glucose for its minimum needs. The problem is that your body does not make enough glucose for its normal needs. Normal functioning still requires some carbohydrate from food.

When your body does not get enough glucose for its normal needs, it triggers hunger, cravings, aches, pains, and low energy levels—just like it does with any other nutrient it needs more of. And these sensations and reactions make losing weight far more difficult than it would be if you simply got the right amount of carbohydrate in your diet. "The right amount" means neither too little nor too much.

Carbohydrate, far from being biologically unnecessary, is actually so necessary that your body must make glucose out of muscle and organ proteins (and glycerol) if you don't get enough carbohydrate from food. It must do this because there are certain cells (mainly blood cells) that must have glucose. If none is available, they will die.

But using muscle and organ protein to make fuel is a very undesirable emergency response. It means you have less muscle (or organ function) afterward. That in itself eventually becomes dangerous to your health. It is also bad for weight loss because muscle burns fat and having less muscle means less fat gets burned. Your body “knows” this. For that reason it produces only just enough glucose for its absolute minimum needs, not for its normal needs. And this is true even if you are eating a lot of protein, as on certain high protein diets.

Most people know that the brain and nervous system strongly “prefer” glucose as their energy source and are the body’s main users of it. These organs by themselves normally require about 130 grams of carbohydrate per day. But in an emergency they "switch over" to using the "ketone bodies" that are one of the by-products of the incomplete burning of fat. This switchover reduces your overall need for glucose. But it’s an emergency response; it very likely means that the brain and nerve cells function inefficiently because they are forced to use their "secondary fuel preference". In practical terms, we can probably say they’re likely to get "sluggish, stupid, and cranky" – typical symptoms of poor weight loss diets.

There is also another reason. Fat "burning" is really a multi-step biochemical process. If this process is stopped at any intermediate step, less energy and more waste products are produced, and the waste must then be eliminated by the liver & kidneys.

A substance called pyruvate is required at a particular step in the metabolism of “fat burning”. If not enough pyruvate is available, the process stops at that point. Remaining steps in the process produce no energy because they never happen. Instead, increased amounts of "unburned" substances of various sorts build up in the blood and must be filtered out and eliminated by other methods.

But pyruvate is a substance that is produced by the "burning" of glucose. In other words, not enough glucose likely means not enough pyruvate and therefore incomplete fat burning. This is another reason why your body needs some carbohydrate from food – to allow it to completely metabolize fat for energy.

Taken together, the various symptoms of the lack of enough carbohydrate from food are called "hypoglycemia" and "ketosis". They are not dangerous to health, but they are both noticeable and very unpleasant sensations.

When you don’t eat enough carbohydrate, your body does not get enough of something that it can only get from food – something that it needs in order to function normally. This is exactly the situation that we say triggers hunger, cravings, aches, pains, and low energy levels. The aches, pains, and low energy levels are probably caused by the "buildup" of the various unusable waste products in your blood during the time before they can be eliminated. The hunger and cravings are your body’s normal signal that it wants you to do something about this.

All of this means that without a certain minimum amount of dietary carbohydrate, your body goes into an "emergency" mode of operation in which it is making “stressful” adaptations that don't really help you lose weight and may slowly destroy tissues you need. And of course your body is also unable to produce all the energy you need for moving around and living normally.

There’s a better way.

How much carbohydrate should you eat to prevent this? Not much, but you should make sure you get that amount and no less. Most physiologists accept that between 50 and 100 grams of dietary carbohydrate per day is the minimum needed to prevent "gluconeogenesis" (the biochemical term for the process of manufacturing glucose in the body). Probably about 150 grams of dietary carbohydrate daily are needed to prevent all symptoms of hypoglycemia and ketosis.

These are the reasons why a lack of carbohydrate makes a very unpleasant and ultimately ineffective diet -- even though you can stay alive without carbohydrate.