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Fat in the blood

DeejayR

DeejayR

Well-Known Member
Messages
2,389
Type of diabetes
Treatment type
Diet only
One thing I didn't glean from last night's BBC tv programme on fat was what happens to fat after it reaches our blood. We were shown people eating things with fat in, and then their spun blood samples with the fat separated, and then the subject went to something else. Can someone please tell me what happens to the fat in my blood, and how does my "full fat" diet affect it, bearing in mind that I'm trying to convert to fat instead of carbs for energy?
I'm looking for reassurance here.
 
I'm not knowledgeable on this subject so hopefully someone will come along. Although carbs turn to glucose in the stomach and appear shorlty after in the blood, fat goes thru a more complex process, so the fat you eat doesn't go directly into the blood which is why blood cholesterol is not directly related to the fat you eat.
 
Just like starch breaks down with the help of enzymes in to smaller, molecules, glucose. This means that it can get through various membranes and go to the cells, fats use enzymes to break down into fatty acids, which are smaller molecules. Sorry that was such a long sentence. :)
 
so the fat you eat doesn't go directly into the blood

According to the TV programme last night it does :D
 
Tm6t7 said:
so the fat you eat doesn't go directly into the blood

According to the TV programme last night it does :D
Click to expand...

Dietary fat does indeed get into our blood and is called cholesterol, the reason we have to fast before a cholesterol lipid panel blood test is so our blood returns to its base level of cholesterol.

People who say that dietary blood does not enter our blood are just incorrect and misguided, you can check this on any reputable scientific/biology based web site.

Fat is transported around our bodies in our blood steam and as fat and blood/water do not mix the fat molecules are encapsulated so that they do not come into contact with the blood and in this form the fat is known as cholesterol.

Thats a very simplistic explanation but basically correct.
 
@Sid Bonkers, that is not just a simplification, it fundamentally is not correct.

Lipoproteins transport cholesterol, and dietary Lipoproteins can skew cholesterol tests because a cholesterol panel checks for blood Lipoproteins, and is an indirect check on cholesterol levels, so, they show up in tests when not fasting. But to call dietary fats in the blood "cholesterol" is fundamentally misleading.
 
I'm no doctor, I just pointed out that the doctors on the TV said fat goes into the blood immediately, and scientifically held up some phials of centrifugally separated blood and said cloudy on top..its fat. End of experiment. Personally I could almost feel them saying (or wanting to say) oops, we have been misled. For 4 decades. For a change. Quelle suprise. Etc Etc :D
 
Tm6t7 said:
I'm no doctor, I just pointed out that the doctors on the TV said fat goes into the blood immediately, and scientifically held up some phials of centrifugally separated blood and said cloudy on top..its fat. End of experiment. Personally I could almost feel them saying (or wanting to say) oops, we have been misled. For 4 decades. For a change. Quelle suprise. Etc Etc :D
Click to expand...
This is my starting point, so I wasn't mistaken in what I thought I heard/saw.

robert72 said:
http://en.wikipedia.org/wiki/Chylomicron
Link explains how fat gets from intestines into the blood stream
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Thanks, some homework for me :)
 
This is relatively simple to follow (2 short videos) , you don't have to understand the chemical make up of the triglycerides (TAG) though she does include it The term hydrophobic comes up at lot : water fearing ie lipids are repelled by water molecules therefore can't easily travel through the watery (aqueous) blood stream. (they tend to lump together like oil on water)
 
Another article that explains how fat enters the body.

http://science.howstuffworks.com/life/cellular-microscopic/fat-cell1.htm
How Fat Enters Your Body

When you eat food that contains fat, mostly triglycerides, it goes through your stomach and intestines. In the intestines, the following happens:

  1. Large fat droplets get mixed with bile salts from the gall bladder in a process called emulsification. The mixture breaks up the large droplets into several smaller droplets called micelles, increasing the fat's surface area.
  2. The pancreas secretes enzymes called lipases that attack the surface of each micelle and break the fats down into their parts, glycerol and fatty acids.
  3. These parts get absorbed into the cells lining the intestine.
  4. In the intestinal cell, the parts are reassembled into packages of fat molecules (triglycerides) with a protein coating called chylomicrons. The protein coating makes the fat dissolve more easily in water.
  5. The chylomicrons are released into the lymphatic system -- they do not go directly into the bloodstream because they are too big to pass through the wall of the capillary.
  6. The lymphatic system eventually merges with the veins, at which point the chylomicrons pass into the bloodstream.
You might be wondering why fat molecules get broken down into glycerol and fatty acids if they're just going to be rebuilt. This is because fat molecules are too big to easily cross cell membranes. So when passing from the intestine through the intestinal cells into the lymph, or when crossing any cell barrier, the fats must be broken down. But, when fats are being transported in the lymph or blood, it is better to have a few, large fat molecules than many smaller fatty acids, because the larger fats do not "attract" as many excess water molecules by osmosis as many smaller molecules would.
 
does this help a bit?

http://www.ketogenic-diet-resource.com/metabolic-pathways.html

metabolic_pathways.jpg
 
My poor head ..... fallflat.gif
 
tim2000s said:
@Sid Bonkers, that is not just a simplification, it fundamentally is not correct.

Lipoproteins transport cholesterol, and dietary Lipoproteins can skew cholesterol tests because a cholesterol panel checks for blood Lipoproteins, and is an indirect check on cholesterol levels, so, they show up in tests when not fasting. But to call dietary fats in the blood "cholesterol" is fundamentally misleading.
Click to expand...

So what part of what I said is wrong?

I would suggest that you read up about it heres something to start with perhaps
http://www.livestrong.com/article/428367-how-are-dietary-fats-absorbed-into-the-body/

Or of course your free to believe whatever you want to but what I posted is correct.
 
My word, I'm going to be SO interesting at dinner parties.



Not that I ever get invited to dinner parties ..:( I wonder why?

Thank you all.
 
DeejayR said:
Can someone please tell me what happens to the fat in my blood, and how does my "full fat" diet affect it, bearing in mind that I'm trying to convert to fat instead of carbs for energy?
I'm looking for reassurance here.
Click to expand...

I hope I'm not oversimplifying things, I've struggled with the Krebs Cycle before, because mine's broken. I think I'm right in saying that the fat is converted into ATP to provide energy for the muscles. In fact, looking back at Jack's message, that's exactly what his wonderful diagram says. I think even I understand it better now I've seen the diagram. Sorry to have repeated stuff. I'm sure I've seen a program recently where they explained why that little demo is just plain misleading along with the old advert they use to show with a jug of fat in the fridge in a liquid state being poured down the drain and clogging it up. The problem being that fat at room temperature is more likely to be fluid than fat in the fridge.
 
Sid Bonkers said:
So what part of what I said is wrong?
Click to expand...
Your first sentence was way off target Sid.

Sid Bonkers said:
Dietary fat does indeed get into our blood and is called cholesterol, .
Click to expand...

The typical daily intake of cholesterol is only about a quarter of one gram, so the vast majority of fat entering our blood is not cholesterol. As explained above in the links posted by several others, most fat is broken down into fatty acids to be absorbed by our bodies.

These fatty acids are then either used by the liver to produce "ketone bodies" that can be used for energy or re-assembled into body fat for energy storage. Some may also be used to synthesise cholesterol, though typically only around a gram or so per day.
 
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