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Venom
11-17-2005, 06:35 AM
Bodybuilders are continually searching for methods to increase fat metabolism. The most important variable to consider for this goal is the amount of calories you metabolize.

There are 3 primary avenues for this: Basal Metabolic Rate (BMR), Exercise, and Diet Induced Thermogenesis (DIT).

BMR is the basic energy requirements needed to maintain vital organs such as the liver and kidney, as well as muscles, which can obviously be manipulated and will greatly increase your BMR. Typically, this accounts for 65% of daily oxidative metabolism. A negative energy balance tends to decrease BMR. Therefore, utilizing methods such as carb cycling, calorie cycling, and avoiding starvation diets is vital for maintaining a high BMR.

Exercise can come in the form of resistance training and aerobics. The amount of calories metabolized from this avenue is dependent on the athletes training program, and can vary considerably.

The last avenue by which we metabolize calories is perhaps the least considered one. This is known as diet induced themorgenesis (DIT). DIT is the increase in the amount of the calories metabolized caused by eating foods. Typically, this accounts for 10% of the calories you metabolize. DIT is determined by several variables including: how many calories you eat, exercise, body composition, the type of macronutrients you consume (fat, carbs, or proteins), and also, the type of fats, carbs, and proteins you consume.

Evidence suggests that lean individuals have a higher DIT than obese individuals. It is suggested that obese individuals have a reduced DIT as a consequence of reduced insulin sensitivity and reduced insulin induced sympathetic tone stimulation and thyroid secretion.

A way to acutely improve DIT is through exercise, which incidentally, enhances insulin sensitivity. Therefore, it is commonly advised to train before eating carbohydrates, to enhance insulin sensitivity, and therefore, DIT.

Chronically, methods which enhance insulin sensitivity may further enhance DIT.

Proteins and carbohydrates generally elicit the highest DIT. This may be caused in part by increased insulin secretion. In contrast, little DIT is found from eating fats. However, this is not always the case.

Here is a quote from Venom (2003), Essential Fatty Acids - An In Depth Analysis (http://www.abcbodybuilding.com/efa.php)

[ QUOTE ]
Thermogenesis

The omega-3 has the distinctive ability of enhancing thermogenesis and lipid metabolism (increased usage of fat), thereby reducing body fat deposition. Clarke SD contributes to this, stating, ‘[Omega-3s exert their] effects on lipid metabolism and thermogenesis by up-regulating the transcription of the mitochondrial uncoupling protein-3, and inducing genes encoding proteins involved in fatty acid oxidation (e.g. carnitine palmitoyltransferase and acyl-CoA oxidase) while simultaneously down-regulating the transcription of genes encoding proteins involved in lipid synthesis (e.g. fatty acid synthase) [14].'

The effect of what they are saying is this: food, as well as our own body, contains what is known as ‘potential chemical energy.’ That is, energy held within the bonds of molecules. A good analogy is to think of a boulder placed on a 100 foot hill. By position, when the bolder is on top of the hill, it has the potential to turn into kinetic energy (the energy of movement) if someone were to tip it off the hill so that it began to roll. High-energy bonds within molecules are high-energy because when those bonds are broken, energy is released, which can be used to do work (force x distance=work).

They use the term Lipid Oxidation for a very specific purpose. The organelle in your body known as mitochondria is responsible for extracting energy from lipids (fats), and using it to synthesize or build our energy currency known as ATP (refer to Adam’s tibialis article). Oxidation is referred to because oxygen is required for this process to occur (oxidation refers to an atom accepting electrons from another atom). The entire process is known as cellular respiration, because you need the respiratory system to consume the oxygen needed for the extraction of energy from these food groups, or stored energy deposits such as your own adipose tissue. Carnitine is an essential protein needed for fat breakdown, and thus, when the body encodes for more of it and other vital proteins required for this process, fat breakdown increases. Genes code for proteins. Likewise, by down-regulating certain genes which code for proteins that enhance the formation of fatty molecules, you logically slow down the process. As a result, the above effects are additive to enhanced fat-burning.


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Other fats such as medium Chain Triglycerides should also have a higher DIT response than other fats. For more information on MCT’s, refer to the last research question of the week, Research Question of the Week: How to Optimize Fat Efficiency in the Diet (http://www.abcbodybuilding.com/forum/showflat.php?Cat=0&Number=1150156&an=0&page=1#1150 156)

With all these variables that can potentially manipulate DIT, a summary of the data would be of practical importance to bodybuilders. Therefore, the purpose of this thread was to engage in a comprehensive discussion on DIT. First, mechanisms by which DIT works in the human body need to be understood in order to effectively manipulate it. Second, we need to discuss the influence of obesity, insulin sensitivity, and any other bodily factors that can influence DIT. Third, once these bodily factors have been identified, how can they be positively enhanced to improve DIT. Fourth, what is the effect of the 3 macronutrients on DIT. And finally, are there differences within these macronutrients in producing DIT.

Venom
11-17-2005, 06:40 AM
I am going to be writing an article on this for the next issue of JHR, and hopefully several others. This one was requested by Mike Z, the President of Champion Nutrition. /forum/images/graemlins/grin.gif

I look forward to hearing some feedback and incite from you guys on this topic. The last research question of the week went fantastic, so if we could replicate that, I would be thrilled. /forum/images/graemlins/cool.gif

John Black
11-17-2005, 10:20 AM
[ QUOTE ]

Proteins and carbohydrates generally elicit the highest DIT. This may be caused in part by increased insulin secretion. In contrast, little DIT is found from eating fats. However, this is not always the case.


[/ QUOTE ]

Is it also true that proteins elicit much higher DIT than carbohydrates?


[ QUOTE ]
A way to acutely improve DIT is through exercise, which incidentally, enhances insulin sensitivity. Therefore, it is commonly advised to train before eating carbohydrates, to enhance insulin sensitivity, and therefore, DIT.

[/ QUOTE ]

Wouldn't it then be more advisable to have a high protein, low carbohydrate meal upon waking, which would be followed by training? Would that have an effect on DIT?

Venom
11-18-2005, 12:32 AM
[ QUOTE ]
Is it also true that proteins elicit much higher DIT than carbohydrates?

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Yup!

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Wouldn't it then be more advisable to have a high protein, low carbohydrate meal upon waking, which would be followed by training? Would that have an effect on DIT?

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Well, when you wake up, insulin sensitivity is already really high, so this would be a perfect time to have carbs. Plus, you optimally would want to have carbs in the morning and pre-workout to decrease catabolism, and for energy during your training session.

littleamazon
11-18-2005, 12:41 AM
So, Gabe...are we using DIT when we carb cycle...on a low carb day?

If I have one training session in the morning and another one in the evening...how would my meal composition during the day look to support DIT?

Amazon

Venom
11-18-2005, 01:34 AM
It depends on how many carbs you are consuming. But what I tried to do was have all my carb meals in the morning or after a workout. One reason being was that insulin sensitivity is optimal at these times, so DIT would be higher. /forum/images/graemlins/smile.gif

littleamazon
11-18-2005, 04:06 PM
[ QUOTE ]
It depends on how many carbs you are consuming. But what I tried to do was have all my carb meals in the morning or after a workout. One reason being was that insulin sensitivity is optimal at these times, so DIT would be higher. /forum/images/graemlins/smile.gif

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You mean, your complex carb meals, all in the morning or after workout?

If you have them all after workout...what happens with the pre-workout meal...and also, what happens to pre and post workout meals if you have all your carbs in the morning? How does that way of eating affect how you schedule your training sessions?

Amazon

stillflabby
11-18-2005, 05:05 PM
I think this explains why I typically get hot, and even sweat during/after a meal. I can feel my body eating up as I'm eating and sometimes by the end of the meal and for quite a while after I'm sweating.

This is especially true when I eat very spicy foods. I know spicy foods (cayenne for instance) increase endorphins and improves circulation in the extremities. I account this to the increased heat, BUT does this also mean DIT is higher?


I guess to sum it up, does eating spicy foods also increase DIT?

Venom
11-18-2005, 07:22 PM
Hey, Carmen /forum/images/graemlins/smile.gif

Here is what a good day might look like for my carbs:

Breakfast: oatmeal
Train
Post workout shake
Later at night...
Cardio
Carbs

That is really all the starchy carbs I can have with my limited intake, and I feel those are the best times to have them.

Venom
11-18-2005, 07:33 PM
[ QUOTE ]
I guess to sum it up, does eating spicy foods also increase DIT?

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Hi

I have heard that it can, but I am not sure by how much. This is a great idea to investigate, though! Thanks. /forum/images/graemlins/smile.gif

11-18-2005, 08:41 PM
I love these research of the week questions! /forum/images/graemlins/cool.gif

I guess I don't really understand insulin sensitivity real well... why is it important to increse its sensitivity?

If I had an unbalanced meal of only oatmaeal and the DIT was 10%.... would it still be 10% if you had oats and tuna? Or 20%? And what if you also had a Tbsp of flax oil? Is the percentage always 10% no matter what you eat?

Venom
11-19-2005, 06:07 AM
Hi, Trillian /forum/images/graemlins/smile.gif

[ QUOTE ]
I guess I don't really understand insulin sensitivity real well... why is it important to increse its sensitivity?

[/ QUOTE ]

Read this post,
here. (http://www.abcbodybuilding.com/forum/showflat.php?Cat=&Board=food&Number=1148326&Search page=1&Main=1148319&Words=%26quot%3Bglute-4%26quot%3B+Venom&topic=&Search=true#Post1148326)

Tell me if you have any more questions on insulin sensitivity after reading that. /forum/images/graemlins/smile.gif

[ QUOTE ]

If I had an unbalanced meal of only oatmaeal and the DIT was 10%.... would it still be 10% if you had oats and tuna? Or 20%? And what if you also had a Tbsp of flax oil? Is the percentage always 10% no matter what you eat?

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NO!

I was giving typical percentages for your entire diet. I.E. if you metabolize 3000 calories in a day, typically, 10% of that will come from DIT. However, this can greatly vary depending on the type of foods you eat.

As stated, proteins and carbs have much higher DITs than fats. The situation gets even more complicated, when considering that certain fats have higher DITs than others. So this is what I am trying to investigate. What foods optimize DIT.

11-19-2005, 03:48 PM
Thanks Venom, that post answered my questions!!

stillflabby
11-21-2005, 03:31 AM
[ QUOTE ]

Hi

I have heard that it can, but I am not sure by how much. This is a great idea to investigate, though! Thanks. /forum/images/graemlins/smile.gif

[/ QUOTE ]

Cool, glad to help.

I'm also wondering if there is a way to trick your body into higher DIT? Maybe certain combinations of foods, or certain times of the day.

From what you said I get:

Protein = Highest DIT
Carbs = Medium DIT
Fat = Lowest DIT

But you also said some Fats elicit higher DIT than others. Is this true of the other macros? I'm "guessing" the more complex and difficult to digest, the higher DIT. Would this be a fair assumption?

If so, are there certain fats that elicit higher DIT than certain carbs?

I think it would be awesome to plan the types of food based on DIT through out the day in conjuction with insulin sensitivity.

I'm thinking meals might go something like:
Lower DIT for Meal 1, PWO meal, and pre-bed meal (pre bed so you don't burn up on the calories more quickly while fasting at night).
Other meals would be higher DIT.

Yet another question.
Let's say you have protein highest DIT and fat, lowest DIT.
Would the presence of the fat lower overall DIT when consumed with protein? Or would it have a slight cumulitive effect?

Sorry for all the questions, but this has my mind racing.
I think I'm done...for now.

Venom
11-21-2005, 10:06 PM
I answered your question and my browser closed out...grrrr. /forum/images/graemlins/mad.gif

Yes, you can “trick” your body to have higher DITs by eating meals when insulin sensitivity is higher or by consuming certain foods with highe DITs. I am not sure if there is a synergistic effect, or of other methods, but it is something to ponder.

One of my primary investigations is to see what foods elicit the highest DIT, such as whey protein combared to steak. I am not sure yet, though. But I would imagine they do have different DITs.

Your hypothesis about complex foods is solid, but I would not assume anything yet. I have to do more investigations.

[ QUOTE ]

I'm thinking meals might go something like:
Lower DIT for Meal 1, PWO meal, and pre-bed meal (pre bed so you don't burn up on the calories more quickly while fasting at night).
Other meals would be higher DIT.

[/ QUOTE ]

I like that idea a lot!

[ QUOTE ]

Yet another question.
Let's say you have protein highest DIT and fat, lowest DIT.
Would the presence of the fat lower overall DIT when consumed with protein? Or would it have a slight cumulitive effect?


[/ QUOTE ]

It will be higher, the extent to which is dependent on the type of fat you consume.

Great questions!

stillflabby
11-21-2005, 10:14 PM
Thank you for the replies.
How do you go about measuring something like this?

Do you take temperature readings during and after? Or is there another way to get this information.

Also, I know it's negligible, but what about the energy it takes to bring cold food to body temp? Is there a way to rule this out, since it's not really diet induced? I realizing consuming food at or above body temp wouldn't affect anything. It might not be enough to worrie about, but I know a few calories (little c) would be burned, and this would add up over time.


BTW I really like this subject, fascinating really!!

gah, I had to edit this twice to get rid of mistakes...I suspect there are more lurking.

Venom
11-21-2005, 10:25 PM
One of the most practiced—and accurate—ways to calculate how many calories you metabolize is to use an indirect calorimetry (spirometry). You would relax, and have your oxygen content measured over a certain period of time. However many liters of oxygen you consumed, just times that by the constant 5.047, and you have how many calories you metabolized. 5.047 can be more properly adjusted if you also have your respiratory exchange ratio (RER). You could compare the amount of oxygen consumed before and after the meal.

Venom
11-21-2005, 10:27 PM
[ QUOTE ]

Also, I know it's negligible, but what about the energy it takes to bring cold food to body temp? Is there a way to rule this out, since it's not really diet induced? I realizing consuming food at or above body temp wouldn't affect anything. It might not be enough to worrie about, but I know a few calories (little c) would be burned, and this would add up over time.


[/ QUOTE ]

That would have an effect but there are not many foods to eat that are really cold, besides ice-cream. /forum/images/graemlins/wink.gif

littleamazon
11-21-2005, 10:28 PM
[ QUOTE ]
Hey, Carmen /forum/images/graemlins/smile.gif

Here is what a good day might look like for my carbs:

Breakfast: oatmeal
Train
Post workout shake
Later at night...
Cardio
Carbs

That is really all the starchy carbs I can have with my limited intake, and I feel those are the best times to have them.

[/ QUOTE ]

So..you only have complex starches at breakfast *oatmeal* Sorry but I only see it listed a breakfast...Don't confuse me Gabe! Grrrr! LOL Now, after cardio/carbs..what carbs are those after cardio: complex, fibrous or combination? And..2 hrs after pwo shake...do you still have complex carb?

Still I need more clarification...when you say you would consume carbs in the morning...does that mean that after a specific time of the day, you switch to protein/fat meals?

So, you are not off the hook yet! /forum/images/graemlins/mad.gif
Could you please be more specific? /forum/images/graemlins/confused.gif Please, pretty please! /forum/images/graemlins/blush.gif LOL

Amazon

Venom
11-21-2005, 10:31 PM
Let's try this again lol...


Breakfast: oatmeal
Train
Maltodextrin/dextrose etc.
Later at night...
Cardio
oatmeal

After this, I will probably go to bed, because it is usually really late, due to the way my schedule works. Otherwise, I would have leafy greens the rest of the day. /forum/images/graemlins/smile.gif

stillflabby
11-21-2005, 10:32 PM
[ QUOTE ]
One of the most practiced—and accurate—ways to calculate how many calories you metabolize is to use an indirect calorimetry (spirometry). You would relax, and have your oxygen content measured over a certain period of time. However many liters of oxygen you consumed, just times that by the constant 5.047, and you have how many calories you metabolized. 5.047 can be more properly adjusted if you also have your respiratory exchange ratio (RER). You could compare the amount of oxygen consumed before and after the meal.

[/ QUOTE ]

Now that's really cool.
Looks like you'd have to get a large sample group to account for other variables that would influence O2 combustion in the body.

Would this be done on humans? Or lab rats maybe?

I can't see a person easily taking in one certain type of fat in a large enough quantity to make an adiquate change in O2 consumption.

Venom
11-21-2005, 10:34 PM
It would be done in humans. I have done it before in a may college lab /forum/images/graemlins/grin.gif

stillflabby
11-21-2005, 10:36 PM
Now that would be an interesting lab to do.

Thanks for all the replies. Good stuff.

Talk about keeping you busy!! /forum/images/graemlins/smile.gif

Venom
12-06-2005, 06:25 AM
Thanks for your feedback, guys. I will post another question of the week in a few days. /forum/images/graemlins/cool.gif

Gibbster
01-27-2006, 10:24 PM
Fat burners of old used to rely on ingredients such as cayenne pepper. I remember they used to heat me up pretty good.