In this article we're going to talk about carbohydrates and how they are stored in the body. Does a large supply of excess carbs make us fat?
Many people believe that only dietary fat will lead to body fat. False! Actually, eating more calories than your body needs to perform daily activities and daily metabolism is what causes body fat. It is as simple as putting 20 gallons of gas in a 15 gallon gas tank.....the excess must go somewhere. In the case of human nutrition, the excess is stored as fat.
Just as excess protein can be stored as body fat, excess carbohydrate can be stored as body fat. Unfortunately for the American public, our consumption of simple carbohydrates has skyrocketed over the last ten years! Too many of us took the popularity of the low-fat and fat-free diets as an excuse to fill up on empty carbo-calories. After all, it's okay to eat the entire package of licorice since it's all fat free....right? Again, False!
Carbohydrates that the body cannot use are stored as body fat, plain and simple. Carbohydrates usually are ingested in the forms of polysaccharides (starches), disaccharides (sucrose and lactose) and monosaccharides (glucose and fructose). Essentially what occurs in the digestive process is a breakdown of the polysaccharides and disaccharides to the monosaccharides. The primary site of digestion is the small intestine, where the monosaccharides are then absorbed into the blood. Of the three monosaccharides, glucose is of most importance to human physiology. This is called blood sugar. Fructose and galactose are converted to blood glucose either in the intestinal wall or the liver.
A high-carbohydrate meal will lead to a rapid increase in the blood sugar level, usually within an hour. Naturally, the higher the food is on the glycemic index (refined sugars), the higher the blood sugar level will rise. The maintenance of a normal blood sugar level is very important for proper metabolism. The human body regulates blood sugar levels by a hormone called insulin. The rises in blood sugar levels stimulate the pancreas to secrete the hormone insulin into the blood. Insulin then facilitates the uptake and utilization of blood sugar by various tissues in the body, most notably the muscles and adipose tissue.
The fate of blood sugar is dependent on many factors, with exercise being one of the most important.
1) Blood sugar may be used for energy, particularly by the brain and other parts of the nervous system.
2) Blood sugar may be converted to either liver or muscle glycogen. Liver glycogen may then be later converted to blood sugar. Muscle glycogen is, for the most part, locked into the muscle cell once it enters, where it is converted to energy.
3) Blood sugar may be converted to and stored as fat in the adipose tissue. This situation occurs when the dietary carbohydrate, in combination with caloric intake of other nutrients, exceeds the energy demands of the body, and the storage capacity of the liver and muscles for glycogen.
4) Some blood sugar also may be excreted in the urine if excessive amounts occur in the blood, because of rapid ingestion of simple sugars.
So, what happens if we don't consume enough carbohydrates? Because the carbohydrate stores in the body are rather limited, and because blood sugar is normally essential for optimal functioning of the central nervous system, it is important to be able to produce blood sugar or glucose internally if the stores are depleted by starvation or a zero-carbohydrate diet. This process is called gluconeogenesis, meaning the formation of glucose. In this process, protein is converted to glucose, and fat is converted to glucose by breaking down glycerol in the liver. The by-products of carbohydrate metabolism, lactate and pyruvate, may also be converted back to glucose in the liver.
With this understanding of how carbohydrate is metabolized in the body, it is clear that low-carb or no-carb diets may lead to decreased levels of energy.
Low-carb diets, however, have been proven to take off the weight. In some cases, weight loss has been dramatic when the subjects abruptly switched to a no-carb diet. Such rapid weight loss is attributed to water loss. Low carbohydrate intake depletes liver and muscle glycogen (stored sugars) and water molecules linked to these sugars. This depletion triggers a drop in body weight.
Especially during the introduction phase of a low-carb diet (2 weeks), the dieter is encouraged to eliminate virtually all carbohydrates from the diet. Even a slight intake of high glycemic foods during this phase would cause immediate weight gain by rebuilding glycogen stores.
Because carbohydrate is the body's preferred fuel source, this first phase of the diet would most certainly challenge exercise enthusiasts.
So, is the low-carb lifestyle right for you? Maybe. We hope that this series of articles has helped you understand low-carb diets and their potential impact on the body.
SOURCE: (International Sports Sciences Association; Frederick C. Hatfield, Ph.D.; 2001)
Low Carb And Cholesterol
In this series of articles we have focused on low-carb dieting. Is it right for you? We have looked at some of the concerns with low-carbing, we've examined the diets of bodybuilders, and we've explained exactly how carbohydrates react in the body. In this final article on the topic of carbs, we will attempt to answer the million dollar question: should you start a low-carb diet?
* THE EXPERTS:
First and foremost, please understand that the majority of physicians in the United States will not recommend a no-carb diet. By and large, doctors are going to follow the generally accepted health practices, and those practices require us to partake of all four food groups. Citing the fact that there are no long-term studies available on the effects of carbohydrate deprivation, the American Heart Association does not recommend a no-carb approach.
On the other hand, there are some doctors who look at the results achieved on low-carb or no-carb diets and say (like some of us have): you can't argue with results!
* THE RESEARCH:
Both sides in the low-carb debate have doctors and studies to back up their claims.
The Atkins group has well-done studies proving that their diet results in weight loss and lower cholesterol. The South Beach folks can quote even more studies. Both groups also do a very good job of trotting out some very convincing before-and-after pictures of people (just like us!) who have seen results on the low-carb diets.
On the other hand, there is no shortage of research proving that low-carb diets are unsafe and ineffective. A study by Linda van Horn of Northwestern University in Chicago assessed more than 4,000 people in the United States, Britain, Japan and China, asking them to write down everything they had eaten over two 24-hour periods. "Lo and behold, what we did find is that without exception, a high complex-carbohydrate, high-fiber, high vegetable-protein diet was associated with low body-mass index (the standard measure of healthy weight)," Van Horn said. The more animal protein a person ate, the higher his or her weight, she said.
It's easy to see that the research conflicts on this issue, as it does on many topics.
* THE ROLE MODELS:
In a previous article we examined the diets of professional bodybuilders and (female) fitness models. Almost without exception, we found that these extremely healthy people did not eliminate all carbohydrates from their diet. Again, almost without exception, these folks did strictly limit the intake of 'garbage' carbs (donuts, cake, cookies, etc.).
Bodybuilders and fitness models get their carbs from quality sources including brown rice, vegetables, fruit and yams.
* PHONE A FRIEND!
Yikes! The experts don't agree and the research doesn't agree! What to do? Let's phone a friend.....
Most of us have a friend or family member that has lost weight on a low-carb plan. Sometimes they've even lost a significant amount of weight. All that anecdotal evidence can't be wrong, can it?
As we learned in a previous article on this topic, low-carb diets will help you lose weight! There's enough research and evidence out there now to fully support that claim. But is it the 'right' weight, and is it 'safe' weight?
Especially during the first two weeks on a low-carb diet, much of the weight loss is attributable to water loss. Falling off the diet, or introducing carbohydrates back into the body, will result in faster-than-normal weight gain from replenished glycogen stores.
Another huge concern with low-carb weight loss success is whether or not it is 'safe' weight loss. We're not talking about heart health or cholesterol levels, but right now we're discussing fat loss vs. muscle loss. After all, nobody wants to lose muscle, do they? When we talk about wanting to lose weight, it's just understood that we want to lose fat! On a low-carb diet, it is very possible to lose far too much weight from muscle and not enough weight from fat.
So although our friends and family may have experienced weight loss on a low-carb diet, that fact alone is not enough to convince us to try it too.
* CAN WE STICK WITH IT?
As we've said time and time again, no diet is going to work for you if you can't stick with it. The Idaho Press Tribune ran and interesting article in defense of low-carbing (3-25-04, LeAnn Coffelt, Your Health section), where some of the challenges of low-carbing were disclosed: carb withdrawal (compared to nicotine withdrawal), hair loss, etc. Perhaps the most intriguing quote of the story was "One of the silliest things I've ever heard is that you will put the weight back on after you stop the diet. Well, of course you will."
Before attempting to lose weight on a low-carb (or any) diet, you simply must ask yourself 'Can I stick with it?'. If you love pasta and pizza, then the answer is probably no.
* THE MILLION DOLLAR QUESTION:
Okay, okay, enough talk about the pros and cons of low-carb life! Should you or shouldn't you 'go low carb'?
Sorry to disappoint you, but nobody can answer that question for you. You, and only you, know if a low-carb diet is something you can stick with for life. There is, however, a list of questions you can (and should!) ask yourself before taking the plunge into low-carb mania:
1) Have I discussed this with my doctor?
2) Do I have a family history of heart disease and/or high blood pressure?
3) Do I have a family history of cholesterol problems?
4) Do I have a family history of cancer?
5) Do I think I can stick with it, even through the 'carb withdrawal' phase?
6) Have I scheduled regular bodyfat tests to make sure I am losing fat and not muscle?
7) Do I have a support system in place to help me stick to my new lifestyle?
8) Have I taken the time to educate myself on the specific diet, or am I simply following the advice of friends?
Low-carb (or even no-carb) dieting may be safe and effective for you. Only your doctor can help you answer that question. In addition, Low-carb (or even no-carb) dieting may be something you can stick with for life. Only you can answer that question.
* OUR FINAL ANSWER:
You didn't really think that we'd conclude this article without a reminder to exercise, did you? After all, exercise is the only thing that all the doctors and experts agree on!
Melanie Polk, RD, is the Director of Nutrition Education at the American Institute for Cancer Research. "We already know how to lose weight and keep it off," said Polk. "It's not a secret: eat less, exercise more. Instead of eliminating all carbohydrates, choose whole-grain options and beans with the fiber to fill you up and provide energy throughout the day. Add vegetables and fruits while cutting back on animal protein and fat."
Doctors agree that exercise is critical to achieving a healthy fitness level for life. Not just a healthy weight, but a healthy fitness level!
Tracie Johanson has sinced written about articles on various topics from Fitness, Lose Weight and Nutrition. Tracie Johanson is the founder of Pick Up The Pace, a 30-minute exercise studio for women, focusing on fitness, health and nutrition for maximum weight loss. Please visit. Tracie Johanson's top article generates over 1500000 views. Bookmark Tracie Johanson to your Favourites.
