Source: Geeksforgeeks

Disclaimer: Copyright infringement not intended.

Context

A low metabolic flexibility to lipid (MetF-lip) in skeletal muscle may promote ectopic lipid accumulation, thus inducing metabolic disturbances. 

What is Meta flexibility?

Metabolic flexibility is the capacity to adapt fuel oxidation to fuel availability so ATP synthesis can match its demand.

ATP synthesis is the process of creating adenosine triphosphate (ATP), the cell's energy carrier, using energy from catabolic mechanisms like cellular respiration, beta-oxidation and ketosis.

What Are Lipids?

Lipids are molecules in our body that are commonly called fats and oils, but they have many important roles beyond just storing energy. They are essential for our health and survival.

Lipids are organic molecules made mostly of carbon, hydrogen, and oxygen.

They are hydrophobic, meaning they do not dissolve in water. Lipids are a source of energy, help in building cell membranes and play a role in hormones and vitamins.

Types of Lipids

Lipids can be divided into three main types:

Type	What It Includes	Role in the Body
Fats (Triglycerides)	Saturated and unsaturated fats	Energy storage, insulation, and protection of organs.
Phospholipids	Found in cell membranes (e.g., lecithin)	Form the structure of cell membranes.
Steroids	Cholesterol and hormones like estrogen	Help produce hormones and digest fats.

Functions of Lipids

Lipids are the body's long-term energy reserve. They provide 9 calories per gram which is more than carbohydrates or proteins.

Lipids are the main building blocks of cell membranes (phospholipids). They protect cells and control what goes in and out.

Lipids act like a cushion protecting internal organs like the heart and kidneys. Fat under the skin helps maintain body temperature.

Lipids help the body absorb fat-soluble vitamins (A, D, E, and K) from food.

Lipids like cholesterol are used to make hormones like testosterone and estrogen.

Whale blubber is rich in lipids and helps them survive in cold oceans.

Lipids are part of the myelin sheath which protects nerve cells and helps in transmitting signals in the body.

Good Fats vs. Bad Fats

Good Fats	Bad Fats
Found in nuts, seeds, fish, and olive oil.	Found in fried foods, junk food, and processed snacks.
Help reduce bad cholesterol (LDL).	Increase LDL and risk of heart disease.
Include unsaturated fats like omega-3.	Include trans fats and excessive saturated fats.

Types of Fats in Lipids

Saturated Fats:

Found in butter, cheese, and red meat.

Solid at room temperature.

Too much can raise cholesterol levels.

Unsaturated Fats:

Found in fish, nuts, and vegetable oils.

Liquid at room temperature.

Help lower cholesterol and improve heart health.

Trans Fats:

Found in processed and fried foods.

Harmful to health as they increase bad cholesterol.

Sources:

NATURE

 

PRACTICE QUESTION Q.Which of the following statements about lipids is/are correct? Lipids serve as a long-term energy storage molecule in the body. Phospholipids are an essential component of cell membranes. Cholesterol is a lipid that plays no role in hormone synthesis. Options: a) 1 and 2 only b) 2 and 3 only c) 1, 2, and 3 d) 1 and 3 only Answer: a)  Explanation: Statement 1 is correct: Lipids are a primary source of long-term energy storage in the body stored as fats in adipose tissue. Statement 2 is correct: Phospholipids are critical for forming the lipid bilayer of cell membranes. Statement 3 is incorrect: Cholesterol is a lipid involved in synthesizing steroid hormones such as cortisol, estrogen and testosterone.