The Science of Fat Loss

---

Just eat less calories!!!

- Any dietitian who ignored how fat cells work

Many people believe it is all about eating less and moving more. As much sense as it makes, that is not how human body works. My blog 'Why eat less, move more doesn't work' explains it very well. Well, calories do matter, but they do not form the basis of fat gain and fat loss. How much calories you eat is a reflection of how much calories your body is already utilizing and saving. If you save less, you eat less. Fat gain is a result of fat cells increasing in size. And in this blog, I tell you how fat cells increase in size. So, let's understand what fat cells really are.

Adipose Tissue

A good way to visualize fat cells is to imagine them as bubble wrap. Each bubble is like an adipose cell (fat cell) and the entire wrap is an adipose tissue. As each bubble is filled with air, adipose cells cells have fat stored in them (in the form of triglycerides).

Subcutaneous fat (fat under the skin) is stored in our body in fat cells, also known as adipose cells or adipose tissue. It's functions are to store fat (in the form of triglycerides) and provide them as fuel for the body, insulation, shock absorption and releasing hormones. In order for fat cells to provide fat for our body's internal energy requirement, it first has to store/accumulate fat. For a metabolically healthy person with good nutrient partitioning, or someone who has been able to maintain the same weight with similar body fat levels, the process of fat gain and utilization of stored fat is balanced and thus their net fat gain in 0.

But, in majority of others, the process of fat storage exceeds it's utilisation and there is storage of excess fat under the skin (subcutaneous) and around organs (visceral). The fat cells get filled with triglycerides and grow in size and weight. Thus, anything that causes a fat cell to gain fat, is the same reason we gain fat. To be more precise, anything that causes fat storage to exceed fat utilisation, makes you gain weight. Now, let's look at the reason why fat cells may increase in size - hormones.

Insulin

Insulin is a hormone released by pancreas that helps in absorption of nutrients nutrients from the intestine. It makes sure that glucose obtained from food gets absorbed in liver, muscle and fat cells. It acts as a gate keeper that knocks on the door of a cell and helps glucose enter inside. It is only in the presence of Insulin, that cells in our body allow the glucose in blood to enter inside so it can be used to produce energy. Normal functional blood glucose levels are around 80-100mg/dL when fasting and 120-140 mg/dL post meals. When blood glucose levels are spiked (raised to a high level in very short duration) over these normal levels, Insulin also gets spiked so all that extra glucose can get into cells.

When you eat foods that get converted to glucose in blood, Insulin acts as a gate keeper, so cells can use that glucose to produce energy. But once cells' energy requirement is satisfied, all the excess gets stored into liver and muscle (as glycogen) and in fat cells (as triglycerides or body fat).

Thus, it helps in storage of excess.

Glucagon

Glucagon works exactly opposite of Insulin. This hormone, released by the pancreas again, gets released when your body notices that you haven't eaten anything in some time and your blood glucose starts to fall under the levels I mentioned above. It knocks on the doors of liver and fat cells, and tells them to utilize the stored glycogen (from liver) and body fat (from fat cells) for energy requirements. Thus, Glucagon helps in using whatever is stored.

An interesting thing to note here is that Insulin and Glucagon share a Yin-Yang relationship. If Insulin levels are high, Glucagon levels fall and vice versa. This forms the basis of fat gain and fat loss.

Now that the base is made, it's time to lift the curtain off and show the real culprits.

Fat Gain

Insulin is a hormone of storage whereas Glucagon is a hormone of utilisation of stored energy (glycogen/fat). We can store up to 100g of glycogen in liver and ~450-500g of glycogen in our muscles. Once these stores are full, all the excess glucose floating in the blood stream goes into fat cells. If this continues for a long time, body gets used to a constant excess of blood glucose. Since all other cells are already taking up as much glucose as they can for energy use, they start ignoring Insulin. If liver and muscle glycogen stores are already full, the only place to for all this excess glucose to go is fat cells.

The following 3 things happen if blood glucose keeps on going up at regular intervals -

1. Cells ignore Insulin's message to let glucose enter inside as they're already full

2. Excess gets stored in liver and muscles as glycogen

3. If glycogen stores are filled all the time, all the remaining glucose is stored as fat

Moreover, since insulin is high, glucagon automatically falls and there is not much use of stored energy. This, if continues over a period of months and years, the fat cells keep on growing in size, and the result is weight gain.

Fat Loss

In fat gain, Insulin is the dominant hormone as glucagon automatically drops in presence of Insulin. Insulin results in anabolism, meaning, growth. In this case, growth in the size of fat cells. If you want to trigger fat loss, all you have to do is reverse the entire process. We know that the hormone Glucagon causes breakdown of stored glycogen and fat. And Glucagon is automatically raised in absence of Insulin, i.e., during times of fasting when there is no spike in blood glucose.

Once body notices that incoming of food/calories has stopped, it smartly reduces Insulin and increases Glucagon. And if you prevent blood glucose from spiking for a very long time, you get in a Glucagon dominant state. Your body will start to mobilize stored fat, reducing the size of fat cell, also known as fat loss.

Note that no where in this blog did you read anything about increasing or decreasing calories. I'm not saying calories don't matter, they do but they are a result of what's going on inside your body. If you store 20% of what you eat, you will automatically eat 20% more calories because you saved a share of what was supposed to be utilized. During fat loss, you will automatically consume less calories because now you are not storing much from the food you eat. Moreover, your body is also using body fat for energy and that adds up to the calorie consumed.

When you follow the basic blueprint of how human body works, maintaining and losing excess weight becomes very simple. If you eat a lot of food that spikes blood glucose, and you are not genetically blessed with better nutrition partitioning, you have the answer to why you gained fat, even though you don't eat enough food. Just reverse it, and you lose fat.

Comment down on this blog or contact me directly if you are struggling with fat gain and want to take a step towards a healthy, strong and lean body. Share this blog with you friends and family :)

Eat Well, Stay Strong, Live Free

Cheers,

Sushil Dhokne