You have three main types of fat: White, Beige and Brown
Brown Fat 
Brown fat is created from muscle (not storage, like white fat) brown fat is immediately available to be burned by your body. (Potential Energy) White fat has to first be turned into brown fat, before it can be converted to energy by your body. Brown fat is generally found in your neck, along the back of your body and around veins and arteries.
Beige fat is created from muscle and converts white fat into brown fat which your body can then burn and turn into energy. (Facilitator) Beige fat is stored in-between the white fat in your body, the amount and ratios of brown, beige and white fat varies greatly from person to person. 
The rate of conversion from white fat to brown fat, by the beige fat, is directly related to the amount of beige fat as a ratio to the white fat.
The actual conversion of brown fat to energy is called thermogenesis and this process is aided by supplements such a L-Carnitine, which has been clinically proven to increase the rate of thermogenesis (burn more fat)
About your fat
You need to understand how fat works to understand the decisions you make regarding the consumption of calories, fats and the amount of exercise that you have to do.
But what if your white fat has very little or reduced amounts of beige fat cells?
You will then struggle to turn white fat into brown fat and your body will convert other, more easier forms of energy before burning white fat.
Some basic principles:
- Your body needs to have brown fat in order to efficiently burn white fat.
- Your body needs to have average levels of beige fat stored in-between your white fat.
- Brown fat can be directly converted to energy
How much Brown fat do you have?
People with higher brown fat levels starts to shiver quicker at lower temperatures compared to other people with lower levels of brown fat.
People with higher amounts of brown fat burns calories at an increased rate of 1.8 times that of people with lower levels of brown fat.
As you get older your levels of brown fat naturally decreases. So, as you get older it becomes more difficult to reduce the levels of white fat stored in your body. Even though your body fears hunger more than it does freezing to death, exposure to a 19 degree environment whilst sleeping has shown clinically to increase the levels of brown fat in the body. When the sleeping environment is heated above 19 degrees the levels of brown fat again declines. Specifically aerobic types of exercise has also shown to increase the levels of brown and beige fat. people with normal blood sugar levels also have higher levels of brown fat than people with high levels of blood sugar.
Weight Loss or breaking down the stored white fat in your body:
Diet supplements: Clinically proven to improve thermogenesis: L-Carnitine (Not all L-Carnitine supplements are the same) but caveat: Only assists brown fat to become available as energy, so the supplement assists the thermogenic process and does not burn white fat.
Exercise: Aerobic type exercise grows brown fat and improves the levels of beige fat
Calories: Vary your calorie intake rate to 4% less than the difference between your estimated consumption and that of your requirement and add half a percent for every 5 years over 40 years of age.
Remember: Muscle weights more than fat. So, even though your body becomes smaller in size, you may actually gain weight, depending on the type of exercise that you do.
Emphasis and BONUS Tips: Sleep in a room where the temperature is around 19 degrees (maybe sleep without your duvet or thinner blankets or sheets?)
Do actual aerobic exercise, create new brown fat and increase the levels of beige fat in your white stored fat.
People living today are struggling even harder to lose weight, even when they are eating less simply because they are not active enough! Get yourself an additional or more hobbies, sit less, do more things, become more active. Avoid eating any sugar or sugary drinks, high carb foods, processed flour, etc. and eat more fresh and uncooked foods.
All information provided for information & education purposes only. Nothing published on https://dietmy.com is intended as substitution for medical advice, diagnosis, or for any treatment.