How is Fat "Burned" out of the body?

barracudamuscle

Ok, I have to warn you ahead of time, it might be technical or too indepth but being an aircraft mechanic I just have to get into every nook and cranny and see how things work and why.

I know that exercise induces the body to "burn" fat and calories while building up muscle my question is whats the physical process? Is that fat drawn into the blood stream for energy, then pumped throughout the body expended by organs and tissues requiring to convert it to energy, then the by product of the expended energy is turned into waste. Now is this waste more often then not carried and dumped into the bladder for urine( which is why drinking so much water is critical for weight loss/health to ease the flow adn make our cells more fluid like) or is it absorbed then converted in the stomach for processing then turned into solid waste?

Basically I'm wondering how the fat is "burned" from the body, is it primarily a solid or a liquid state when it is expelled from the body's energy source? I know weird question, if anyone has a link to a good explaination or knows the answer that'd be great! I know it might be like asking what came first the chicken or the egg...

Once again sorry, it's the mechanic in me to want to know the hows/whys/when

Best Dishes!
Pat

barracudamuscle

Ok, I have to warn you ahead of time, it might be technical or too indepth but being an aircraft mechanic I just have to get into every nook and cranny and see how things work and why.

I know that exercise induces the body to "burn" fat and calories while building up muscle my question is whats the physical process? Is that fat drawn into the blood stream for energy, then pumped throughout the body expended by organs and tissues requiring to convert it to energy, then the by product of the expended energy is turned into waste. Now is this waste more often then not carried and dumped into the bladder for urine( which is why drinking so much water is critical for weight loss/health to ease the flow adn make our cells more fluid like) or is it absorbed then converted in the stomach for processing then turned into solid waste?

Basically I'm wondering how the fat is "burned" from the body, is it primarily a solid or a liquid state when it is expelled from the body's energy source? I know weird question, if anyone has a link to a good explaination or knows the answer that'd be great! I know it might be like asking what came first the chicken or the egg...

Once again sorry, it's the mechanic in me to want to know the hows/whys/when

Best Dishes!
Pat

lotusfromthemud

My doctor told me (I wanted a non-technical answer) that "you pee it out." Which would explain the whole water is important thing.

sindyb9

Dont know if this will help. Good website though

The digestive system includes the digestive tract and its accessory organs, which process food into molecules that can be absorbed and utilized by the cells of the body. Food is broken down, bit by bit, until the molecules are small enough to be absorbed and the waste products are eliminated. The digestive tract, also called the alimentary canal or gastrointestinal (GI) tract, consists of a long continuous tube that extends from the mouth to the *kitten*. It includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The tongue and teeth are accessory structures located in the mouth. The salivary glands, liver, gallbladder, and
pancreas are major accessory organs that have a role in digestion. These organs secrete fluids into the digestive tract.

Food undergoes three types of processes in the body:

Digestion
Absorption
Elimination
Digestion and absorption occur in the digestive tract. After the nutrients are absorbed, they are available to all cells in the body and are utilized by the body cells in metabolism.

The digestive system prepares nutrients for utilization by body cells through six activities, or functions.

Ingestion
The first activity of the digestive system is to take in food through the mouth. This process, called ingestion, has to take place before anything else can happen.

Mechanical Digestion
The large pieces of food that are ingested have to be broken into smaller particles that can be acted upon by various enzymes. This is mechanical digestion, which begins in the mouth with chewing or mastication and continues with churning and mixing actions in the stomach.

Chemical Digestion
The complex molecules of carbohydrates, proteins, and fats are transformed by chemical digestion into smaller molecules that can be absorbed and utilized by the cells. Chemical digestion, through a process called hydrolysis, uses water and digestive enzymes to break down the complex molecules. Digestive enzymes speed up the hydrolysis process, which is otherwise very slow.



Movements
After ingestion and mastication, the food particles move from the mouth into the pharynx, then into the esophagus. This movement is deglutition, or swallowing. Mixing movements occur in the stomach as a result of smooth muscle contraction. These repetitive contractions usually occur in small segments of the digestive tract and mix the food particles with enzymes and other fluids. The movements that propel the food particles through the digestive tract are called peristalsis. These are rhythmic waves of contractions that move the food particles through the various regions in which mechanical and chemical digestion takes place.

Absorption
The simple molecules that result from chemical digestion pass through cell membranes of the lining in the small intestine into the blood or lymph capillaries. This process is called absorption.

Elimination
The food molecules that cannot be digested or absorbed need to be eliminated from the body. The removal of indigestible wastes

www.ask.com
and this website goes into further details: http://recipes.howstuffworks.com/food2.htm

AJCM

That is a good question! I would also love to know - not the general (that it is excreted by the four systems) but what is the process FROM my thighs TO my breath, sweat, urine, and, well, you know the fourth one...

Where's Banks?... Banks, are you there?

I have a feeling he will know the answer...

banks1850

this may help.
I don't go into the how the body breaks down food, but I'm not sure that really matters as everything you eat is converted into a kind of slurry anyway.

http://www.myfitnesspal.com/topics/show/10589-for-those-confused-or-questioning-eating-your-exercise-calo

edyta

This article is also good:
http://www.fitsense.co.uk/fit_article.php?id=100

I don't remember who posted it (it was a while ago) but thank you :flowerforyou:

yellow_pepper

When you burn your own body fat, it compusts into several by-products. One is cholesterol: burning fat temporarily raises your blood cholesterol. But this is ok ... It's temporary!

Incidentally, the people with the highest cholesterol are actually ANOREXICS. Surprising? Consider that they are actually digesting their organs, like their liver, because it's the richest source of nutrients available. So it's as if they are eating a steady stream of liver. Of course their cholesterol rises!

Farther down the fat-burning pipeline is a by-product called ketones, which are excreted through the urine. And of course, more carbon dioxide.

So, what's in the other waste products? Here are the basics:

In addition to ketones (fat combustion by-products), urine carries water, urea (broken down protein from food and muscles) and for people whose blood sugar is WAY over where it should be, glucose.

Your breath excretes the end-product of glucose combustion - carbon dioxide and water.

Your sweat is water and salt - no "toxins" - sweat is actually pretty clean stuff.

Your feces is mostly fiber, both the soluble (e.g. oatmeal) and insoluble kind (e.g vegetables). But it can also include other things that just weren't digested completely, either because you don't chew very well, you got sick, or you took one of those weight-loss drugs that push fat through your system. If you're intolerant to a particular nutrient or additive, it can also find its way out this way - e.g. byproducts of sugar alchohols like maltitol and sorbitol, and other things that cause flatulence.

On that note, have a GREAT LUNCH!
YP

songbyrdsweet

I'm not sure if you're asking about expelling the waste or actually using the fat, but I can tell you how it's used.

Generally, low insulin/high glucagon levels will promote the release of triglycerides into the blood stream where they can be available for use by surrounding tissues and can undergo lipolysis. Long-term exercise and not eating for a while can promote this.

At rest, about 70% of your energy needs come from the breakdown of triglycerides (fats). This is because oxygen is required for the system and it's fairly slow, so it's more appropriate for resting energy needs rather than exercise-energy needs (however, we do use some fat oxidation while we exercise, so don't stop!)

A triglyceride is made of a fatty acid and some glycerol, basically. Lipolysis, meaning fat breakdown, 'breaks' apart these pieces. The glycerol can be used to make glucose, which is blood sugar, and we use that for energy in a cycle called glycolysis; it creates energy for moderate-very high intensity exercise. The fatty acid is used in a cycle called the Krebs cycle, which creates energy for moderate-very low intensity exercise.

Basically, these constituents enter the cycle and a series of reactions occur that lead to the production of ATP, which is really what we use for energy in the body. Fat isn't literally burned, but broken into smaller pieces and used in bigger systems.

FatDancer

Your so smart and cool Songbyrd...so glad you share with us all!

songbyrdsweet

Your so smart and cool Songbyrd...so glad you share with us all!

Awwwwe thank you! I'm glad you let me rehearse all this stuff so I don't forget it hehe :laugh: Now that the semester's over I actually have time to post! :bigsmile:

sgtinvincible

songbyrd, anytime you need us to verify your 'extra cirricular' activities for extra credit, just let us know. :laugh:

Very nice info. :drinker:

cp005e

This is a good link on how different substances are metabolized: http://www.faqs.org/nutrition/Met-Obe/Metabolism.html

I also found this online, but it's not as scientific (http://www.afn.org/~poultry/eggdiet.htm):

When your body needs glucose and isn’t getting enough from your digestive system, it will convert stored body fat into glucose. Ketones are chemical waste byproducts of this fat-to-glucose conversion. Although not scientifically correct, you can think of Ketones as being “Liquid Exhaust Fumes from Burning Fat”. These Ketones are picked up by the kidneys and expelled in the urine. The more Ketones that are present in the urine, the more fat you have lost.

AJCM

Thanks for all the replies - OMG - VERY knowledgeable crowd!!!
:flowerforyou:

Interesting about the higher cholesterol! I would never have guessed, but makes perfect sense!!! I'm having a physical on Monday - will my cholesterol levels be elevated?!?!

barracudamuscle

Excellent responses by everyone, much appreciated! Very knowledgable crowd! Now if anyone has questions about aircraft, flight, turbine theory and efficency I might be able to help... When it comes to food and body stuff all I can tell you is if it taste really good, its not good for your body! If you can see through the paper bag its your window to weight gain! Don't forget, desserts are essential to a balanced body and always be sure to eat dessert first so you don't miss out, you never now what can happen, nothing like evacuating a chow hall getting hit without getting dessert ( Its happened!)
:drinker: