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15 votes
Accepted

What animal has fat with the highest energy density?

In both humans and animals, the body fat stores appear as triglycerides, which can be composed of different fatty acids, but they all have about 9 kilocalories per gram (USDA). There can be different ...
Jan's user avatar
  • 8,079
14 votes
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Can the human body create glucose out of fat?

Only about 5–6% of triglyceride (fat) can be converted to glucose in humans. This is because triglyceride is made up of one 3-carbon glycerol molecule and three 16- or 18-carbon fatty acids. The ...
David's user avatar
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12 votes
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How does the human body extract energy from ethanol?

Preamble The question suggests unfamiliarity with the nature of biochemical oxidations and their relation to energy transfer in biology. The naïve reader is recommended to consult a text for a ...
David's user avatar
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9 votes
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Is palmitic acid really that dangerous?

Let's first clarify some concepts. Free fatty acids, including palmitic acid, are not present in animal tissues (or in the diet) to any large extent; they are esterified with glycerol to from ...
Roland's user avatar
  • 5,705
9 votes
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How can grass-fed livestock generate fat?

Short answer Plants typically store energy in the form of starch. Animals, including livestock and humans for that matter, can digest starch, metabolize it into acetyl-CoA and turn it into fat. ...
AliceD's user avatar
  • 52.5k
9 votes

How does body fat leave your body?

Many of the statements in your question are false, including your ideas about waste products. Ultimately, fats, just like carbohydrates, end up as water and carbon dioxide if they are used in ...
Bryan Krause's user avatar
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8 votes
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When you lose weight, how does the mass exit your body?

as CO2 and water in respiration sugar (or fat) is combined with oxygen to produce energy(ATP and heat), water, and CO2. fats are converted to Acetyl Co-A just like glucose is, the rest of the ...
John's user avatar
  • 14.7k
8 votes
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Why are fatty acids consisting of even number of carbons predominant?

In short, it's because fatty acids are made from two-carbon blocks. The way that most organisms make fatty acids is by the successive addition of two-carbon units (acetyl-CoA). So we usually get ...
julianstanley's user avatar
8 votes
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Does LSD "stay" in your fat storage and then "returns" back?

I've heard this rumor for years, both from pro- and anti-drug people, and it is not true. According to this review of LSD's pharmacology, its half-life in the body is about 5 hours, with it being ...
MattDMo's user avatar
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7 votes
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Breathing faster to lose (more) weight?

The rate of CO2 production is normally set by the rate of metabolism and breathing rate is determined by the level of CO2 in the blood. What you are suggesting is known as hyperventilation. Because ...
Alan Boyd's user avatar
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6 votes
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Why is glycerol kinase absent from adipocytes but present in the liver?

The short answer to this question is given in the Wikipedia article on glycerol kinase: Adipocytes lack glycerol kinase so they cannot metabolize the glycerol produced during triacyl glycerol ...
David's user avatar
  • 26k
6 votes
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Why are fatty acids synthesized in two carbon units?

The answer to this question lies in the chemistry of fatty acid synthesis — specifically the chemical energetics of the reactions. For those new to the biochemistry there is a basic concept that must ...
David's user avatar
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5 votes
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Can lactate be created in ketosis?

First, there are inaccuracies and misconceptions in the article you quote, which also relates to obese people with insulin-resistance (pre type II diabetics) rather than normal people. These are: I’m ...
David's user avatar
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5 votes
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Why does open olive oil keep so long?

Bacteria and other Microorganisms are mostly water, and to replicate they will need more water. The water they need is not present in olive oil. Salts and other required elements are also not present ...
timeskull's user avatar
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4 votes

Is the amount of cholesterol the body produces affected by how much cholesterol you take in with food?

Here's a study in which they measured a decrease in endogenous cholesterol synthesis after various amounts of dietary cholesterol: Dietary Cholesterol Feeding Suppresses Human Cholesterol Synthesis ...
Jan's user avatar
  • 8,079
4 votes

Where does weight go when you lose it?

You breath it out, for the most part. Fat is "burned" to convert the carbons to CO2, which is breathed out. There's not very much fat-derived carbon in each breath, but you breath a lot, all ...
iayork's user avatar
  • 14.2k
4 votes

Why do humans lose subcutaneous fat tissue with age?

Short answer We do not loose fat (cells) as we age; on the contrary - we tend to gain fat by about 1 or 2% per decade. The place where it gets stored does change; instead of going into subcutaneous ...
AliceD's user avatar
  • 52.5k
4 votes

Why does the liver produce ketone bodies instead of exporting acetyl-CoA from beta-oxidation for use elsewhere?

This is simplified version of a complex situation, but in summary: A key role of liver is to control the distribution of metabolic fuel for the other tissues (it always has enough for its own ...
David's user avatar
  • 26k
4 votes
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Can fats clog veins or capillaries?

I know that so much fats running in the bloodstream could deposit in arteries, harden forming a plaque and cause atherosclerosis. But what about veins (which are formed from same types of layers as ...
user1850479's user avatar
3 votes

Breathing faster to lose (more) weight?

There are two organs which govern pH: the lung and the kidney. If one is having some problem the other steps in to correct it. The body does not like pH to drift far from 7.4. CO2 gas is blown ...
Willk's user avatar
  • 2,964
3 votes

How can grass-fed livestock generate fat?

Same way animals can turn sugars to fats, chain reactions involving multiple enzymes. Some plants, e.g. potatoes, rice etc. will store very little fat. Most plants will only store a bit of fat in the ...
Oliver Houston's user avatar
3 votes

Can the human body create glucose out of fat?

To be more detailed it is the irreversibly of the reaction carried by Pyruvate dehydrogenase that makes the conversion of the fatty acid chains to glucose impossible. The fatty acids chains are ...
blu potatos's user avatar
3 votes
Accepted

Why is glycerol the backbone of fat?

Chance should always be high on our list of explanations of why the history of life turned out in some specific way. As James A. Coffman has described, there are a couple of different notions of ...
Galen's user avatar
  • 1,055
2 votes

Does the body prioritise the use of available sugar before fat?

In a very simplified explanation - the body usually picks the process which is easiest/ fastest which would be to absorb the glucose then the fat would be used for energy as this takes longer to ...
CatCochrane's user avatar
2 votes

Synthesis of Fatty Acids Longer than 16 Carbons

Short Answer: Yes. Long Answer: See this article: The diagrams presented show how fatty acids are synthesized in microorganisms and list the enzymes found in Escherichia coli. These reactions are ...
another 'Homo sapien''s user avatar
2 votes

Is there such substances that body can only send to storage (as fat)?

An empty calorie is still a calorie. "Empty calories" was coined to describe foods that only provide calories without significant amounts of other nutrients. The idea is that if you're eating a lot ...
bpedit's user avatar
  • 1,351
2 votes

After fat is burned from one part of the body, is fat moved around the body?

Fat burning is a generalized procedure so there is no such a thing that some part of body loses fat and other part gains it. Targeted Fat Loss still is a myth.
Xaqron's user avatar
  • 432
2 votes

Breathing faster to lose (more) weight?

Disclaimer: Not a doctor, a biologist, or a scientist. This TEDx talk by Ruben Meerman explains the process of the mass loss via CO2 via exhaling. The mathematics of weight loss | Ruben Meerman | ...
Russell D's user avatar
  • 121
2 votes
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Why does the amount of adipose tissue contribute the most to the total body water amount in humans?

Fat mass does not take up water. It brings with it less water percentage than lean mass and so a person with more fat mass will have relatively less % body water. Additional mass as fat contributed ...
Willk's user avatar
  • 2,964
2 votes

How would a medication cause a one to maintain a different weight?

Based on my reading, weight gain, as in resetting your maintenance set-point, which is what it sounds like you are describing, is a very well-known side-effect of the serotonin selective reuptake ...
mdperry's user avatar
  • 3,517

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