The secret life of fat cells - 24 things you did not know about fat

All you ever needed to know about fat tissue and fat cells

• Fat cell birth to fat cell death: the secret life of fat cells

• Adipocyte differentiation = fat cell birth

• Fat cells live for 10 years

• Fat cells recycle all the fat stored in them every 18 months

• Fat tissue stores fat-soluble toxins in it

• You can grow new fat cells if you overeat / do not exercise

• Liposuction only removes existing fat cells. New fat cells can grow even on an operated spot.

• You can grow ‘ectopic’ fat in weird places if you overeat / do not exercise

• Cellulite fat cells

• Fat cells can expand 3,000 (Three thousand) times their normal volume

• Replacing firmness with flab. Literally.

• Replacing flab with firmness

• Overgrowing fat cells can suffocate themselves. This is bad news.

• Fat tissue and collagen

• ‘Hard’ and ‘soft’ cellulite

• Fat tissue is a gland

• Insulin resistance and overall adipose tissue size and health…

• Visceral fat cells and inflammation

• “I hate my fat”

• Adipocyte apoptosis = fat cell death

• Adipocyte necrosis = Instant tissue destruction

• Melt the fat? Seriously? It’s already liquid!

• Beige, white, brown fat cells

• White fat cells

• Brown fat cells

• Beige fat cells

• Senile fat cells

• Fat tissue: good in small amounts, lethal (and unsightly) in high amounts

Fat cell birth to fat cell death: the secret life of fat cells

One way or another, and for better or worse, we are all obsessed with fat - especially every spring and summer. However, despite all that preoccupation, it is surprising how little we all know about fat. And unfortunately most of what we think we know is wrong.

As part of my focus on fat/cellulite reduction, I have been following the research on adipose tissue for more than two decades now and I am pleased to share these 24 very important yet very little-known facts about fat and fat cells with you.

Adipocyte differentiation = fat cell birth

If there is a need for them (calorie surplus, hormonal factors), new fat cells are “born” every day from stem cells via the process of adipocyte differentiation.

With adipocyte differentiation, mesenchymal stem cells give rise to pre-adipocytes which in turn become mature adipocytes, i.e. fat cells.

Fat cells are the stuff we love to hate in the West but it is also the stuff that keeps helping people survive in poor countries and helped humans (and all animals) survive for millions of years.

How long do fat cells live?

According to research, fat cells ('adipocytes') live for an average of 9.5 years and are then replaced by new fat cells, as described in the above paragraph.

Fat cells recycle all the fat stored in them every 18 months

During their life, fat cells recycle their fat content six times, i.e. the same fat/oil molecules stay in the same fat cell for about 18 months.

Younger / healthier people recycle fat faster in and out of their fat cells.

Diabetics, people with metabolic problems and older people recycle more slowly.

Fat tissue stores fat-soluble toxins in it

Together with fat molecules, fat-soluble toxins also stay in the same fat cell for about 18 months, constantly and slowly being absorbed from - and being released into - the circulation.

When we lose a lot of weight, fat-soluble toxins are also released into the circulation faster than normal, often leading to what some people call “detox reactions” and “flashback“ events.

You can grow new fat cells if you overeat / do not exercise

At any given time, new fat cells can be created anywhere in the body to accommodate excess calories from too much eating and/or too little exercise.

This is the reason people regrow new fat even in the same areas where fat was removed by liposuction.

If you eat too much and move too little, there is no escape: you can grown new fat cells literally anywhere in the body. And this is quite right, as otherwise you would die from all the excess food-derived glucose and fat circulating in your bloodstream.

In this sense, your fat tissue acts as a life saving “dumping ground” for dietary excesses and calorie imbalance.

Liposuction only removes existing fat cells. New fat cells can grow even on an operated spot.

As mentioned above, if you don’t care about your diet/exercise after lipo, fat will grow in another, non-operated area. Eventually, fat can regrow even on an area operated with liposuction.

Liposuction is an absolution of past dietary “sins”, but does not protect from new dietary sins.

You can grow ‘ectopic’ fat in weird places if you overeat / do not exercise

With excessive calorie imbalance we can have fat growing in “weird” places, such as:

• Inside skin (what we call ‘cellulite’)

• Inside bones (part of the osteoporosis condition)

• Around blood vessels (‘perivascular adipose tissue’)

• Between organs (‘visceral fat’, better known as “pot belly”

• Inside muscles (‘intramuscular fat’; yes, just like the marbled fat of a rib-eye steak)

• Inside connective tissue (lipomas, which fatty benign growths)

All these are examples of what is called ‘ectopic fat’.

Cellulite fat cells

Cellulite fat cells are no different to other thigh fat cells, except for being located in the skin itself, as opposed to the deeper, subcutaneous adipose tissue.

However, both cellulite and subcutaneous fat cells are quite different to stomach fat cells:

• They respond to different hormonal stimuli (estrogen for cellulite/thigh fat cells, cortisol for stomach)

• They are smaller and more numerous (while belly fat cells are larger and less in numbers)

However, cellulite fat cells have something in common with stomach fat cells: they are both prone to inflammation (subcutaneous fat cells less so).

Fat cells can expand 3,000 (Three thousand) times their normal volume

As they expand, fat cells need to break down the collagen-rich connective tissue around them to make space for their expansion to grow up to 3,000 times bigger.

In the process they turn firmness into flab. Literally.

Replacing firmness with flab. Literally.

If we are inactive, collagen cells (‘fibroblasts’) tend to go into ‘apoptosis (i.e. programmed cell death) and to be replaced by fat cells (adipocytes).

This process again turns firmness into “flab”. Literally.

Excessive food intake accelerates this process, as there is more need for new and bigger fat cells in the body.

Replacing flab with firmness

Moving a lot, irrespective of diet, can stimulate the growth and well-being of collagen cells (‘fibroblast differentiation’) and inhibit the growth of fat cells (‘adipocyte differentiation inhibition’).

So keep bouncing about, it’s good for you, as it can turn flab into firmness.

Overgrowing fat cells can suffocate themselves. This is bad news.

If fat tissue grows too fast, it inhibits its own circulation which ends in low oxygen levels (‘adipose tissue hypoxia’), fat tissue inflammation, senescence and fibrosis.

When this occurs in visceral fat (deep stomach fat), risk of cardiovascular disease increases.

If this occurs inside the skin, we call it “cellulite” - quite often painful cellulite.

In any case, fat hypoxia is not a good idea, so keep those fat cells nice and small and your circulation going, by eating healthily and staying active.

Fat tissue and collagen

Fat tissue always contains a certain amount of connective tissue made of collagen fibres around and inside it. The more collagen there is, the more firm the fat tissue is. The less the collagen fibres, the “flabbier” the fat tissue is.

Fat tissue (in white) and collagen tissue (in pink). The red circles in the individual fat cell illustration are the cell nuclei and the cream coloured bubbles are the lipid droplets (fat is liquid in fat cells).

‘Hard’ and ‘soft’ cellulite

This is the same with cellulite. What people call “hard cellulite” is cellulite with a lot of hard, sometimes fibrotic, connective tissue in it.

“Soft cellulite” is the opposite: lots of fat and water retention and less collagen-rich tissue.

Fat tissue is a gland

Fat tissue is a not just a storage space for excess calories, it is a fully functioning endocrine organ (a gland, one could say).

It produces and metabolises different hormones, as well as hormone-like substances, called ‘adipokines’. Most of those are detrimental to health, as they cause ‘insulin resistance’ (pre-diabetes) and/or inflammation.

Plus fat tissue secretes estrogen - even in men.

The larger this “gland” becomes, the more it disrupts your hormonal balance.

Insulin resistance and overall adipose tissue size and health…

…can be improved by having less calories overall, less sugar, less carbs, less saturated fat. And more vegetables, more lean protein, more herbs and spices, more berry fruits and more omega-3 fats.

Simple.

Visceral fat cells and inflammation

Both visceral fat (i.e. stomach fat) and hypodermal fat (cellulite) produce a higher amount of pro-inflammatory substances, but ‘subcutaneous fat’ (what we call “fat”) is not great either in that respect.

“I hate my fat”

Many people say “I hate my fat”, but few realise that fat tissue saves their life literally every day.

As mentioned above, without fat tissue, glucose and fat from an imbalanced diet would accumulate in the bloodstream very quickly, leading to death.

Luckily, fat tissue acts as a sponge for sugar and fat, clearing them out of the blood circulation. The end result of this accumulation is overweight and obesity, which is not great but is much better than death.

Adipocyte apoptosis = fat cell death

Cosmetic treatments, such as cryolipolysis (“fat freezing”), ultrasound cavitation and radiofrequency, reduce fat via a process called ‘adipocyte apoptosis’ (literally meaning “falling off”) and by a process called ‘lipolysis’, which refers to releasing fat from fat cells into the circulation.

These treatments don’t destroy fat cells there and then, but they weaken them, leading them to gradually commit suicide (‘programmed cell death’).

Adipocyte necrosis = Instant tissue destruction

If these techniques are applied excessively (for faster, “miracle” results, as touted by some clinics for a hefty fee) they can cause ‘necrosis’, which literally means “death”.

Necrosis is not miraculously limited to fat tissue, it also kills other useful tissue around fat cells, leading to injury, inflammation and scar tissue “bumps” - clearly not a good idea.

So it’s better to avoid those rip-off one-session miracle procedures.

Melt the fat? Seriously? It’s already liquid!

You can’t melt your fat, as claimed for different treatments, creams and even “infrared-emitting ceramic-infused fat melting” clothing. This is all marketing BS.

Fat in fat cells is already liquid anyway (scientists call them ‘triglyceride droplets’ for a reason).

And you cannot “melt” fat tissue itself without literally burning it, together with all the other useful tissues around it.

As I mentioned just above, literally burning the adipose tissue with a miracle one-session procedure is not a good idea.

Beige, white, brown fat cells

There are three types of fat cells: white fat cells, brown fat cells and beige fat cells, because of how they look in the microscope.

White fat cells

White adipocytes accumulate fat.

They clear out all the excess fat that we eat and store it for future use (and in the process preventing us from dying of diabetes or a heart attack, as mentioned above).

In return they quite often secrete inflammatory substances, which are not very good for us.

Brown fat cells

Brown adipocytes burn fat. Quite a lot if it. In mice only, really.

Scientists have been trying to find the ultimate drug / supplement / herb / method to make our fat cells burn fat (what is called ‘brown adipocyte thermogenesis’), instead of storing it, but unfortunately with no avail for the moment.

Unfortunately we - unlike mice - have very little of it, so no luck here.

Beige fat cells

Then there are beige adipocytes. These are white adipocytes that turn brown (-ish) and they also burn fat.

White adipocytes can be stimulated to turn into beige ones, by intensive exercise, certain herbs and certain stimulants. But above all, what turns white fat cells into beige ones is cold: as in cold room temperature or cold-water bathing - every day, not once in a while.

At the moment the best ways to stimulate beige fat and thermogenesis, without getting pneumonia with all the cold baths and freezing cold room temperature, is exercising intensively and eating lots of vegetables and herbs.

I know, hardly revolutionary knowledge, but that’s how it is…

Senile fat cells

Fat tissue is a rich source of “senescent cells”, i.e. ageing cells that short-circuit the immune system and cause a state of hyper-inflammation throughout the body.

Not great for diseases such as Covid-19 then, which is known to cause cell senescence.

Older / overweight people suffer more from cellular senescence.

Vice-versa, cellular senescence increases the risk of severe covid, so this is yet another reason to keep your fat levels controlled - especially visceral fat levels.

Fat tissue: good in small amounts, lethal (and unsightly) in high amounts

Generally speaking, fat tissue has multiple roles to play - all positive in small amounts, and generally negative in high amounts.

So the old adage of “eat healthily, keep active” stays true. In addition, some things do help reduce fat locally (deep-acting, high-power radiofrequency and high-power ultrasound cavitation) or throughout the body (ozempic, mounjaro etc), but always in combination with diet and exercise.

However, miracle shortcuts do not exist and usually cause more damage than good.