#uncat 

## Basic facts
The chemical family name for fats and related compounds is **lipids**, from lipos, the Greek word for "fat"

Liquid fat is **oil**, solid fat is **fat**, the fat in food is **dietary fad**.

With the exception of **[[Cholesterol|cholesterol]]** and other **sterols** (a fatty substance that has no calories and provides no energy), dietary fats are high-energy nutrients.

## How your body uses fats
Some of the **adipose** (fatty) tissue in your body is visible - in female breasts, hips, thighs, buttocks, belly, and on the male abdomen and shoulders

This relatively visible body fat:
- provides a source of stored energy
- gives shape to your body
- cushions your skin
- acts as an insulation blanket that reduces heat loss

Other body fat is tucked away in and around your internal organs
This hidden fat is:
- part of every cell membrane
- a component of **myelin**, the fatty material that sheathes nerve cells and makes it possible for them to send electrical messages
- a constituent of hormones and other biochemicals
- a shock absorber

## Absorbing energy

Though dietary fat is richer in calories, your body has a more difficult time pulling the energy out of fatty foods than others because the fat floats on top of the watery food-and-liquid mixture in your stomach, which limits the effects of **lipases**, the enzymes that break fats apart so you can digest them.
Because of that, fat is digeste more slowly, so you feel fuller, a condition called *satiety*, longer after eating high-fat food.

## [[Digestion]]
When the fat moves down into your digestive tract into your small intestine, an intestinal hormone called **cholecystokin** alerts your gallbladder to release **bile**.
After bile enables fats to mix with water, lipases break the fat into **glycerol** and [[Fatty acids|fatty acids]]. These smaller fragments may be stored in fat cells in adipose tissue, or absorbed into cells in the intestinal wall where they're either combined with oxygen to produce heat/energy, water, and the waste product carbon dioxide, or used to make lipoproteins that haul fats through your bloodstream.

### Stored fat
When your carbohydrates are low, it's time to start in on your body fat.
The first step is for an enzyme in your fat cells to break up stored **triglycerides**. The enzyme action releases glycerol and fatty acids, which are then transported through your blood and burned for energy.
Burning fat also produces **ketones** (for people on a [[Diets|keto diet]] the more likely sign is **ketosis**, stinky urine or breath that smells like acetone)


## In food
![[Pasted image 20241219031809.png]]

As a general rule:
![[Pasted image 20241219032950.png]]
![[Pasted image 20241219033018.png]]