Many of us may be considering “burning some fat” so we feel
better in our bathing suits out on the beach or at the pool. What does
that actually mean, though?
The normal fat cell
exists primarily to store energy. The body will expand the number of
fat cells and the size of fat cells to accommodate excess energy from
high-calorie foods. It will even go so far as to start depositing fat
cells on our muscles, liver and other organs to create space to store
all this extra energy from calorie-rich diets – especially when combined
with a low activity lifestyle.
Historically, fat storage worked well for humans. The energy was stored as small packages of molecules called fatty acids,
which are released into the bloodstream for use as fuel by muscles and
other organs when there was no food available, or when a predator was
chasing us. Fat storage actually conferred a survival advantage in these
situations. Those with a tendency to store fat were able to survive
longer periods without food and had extra energy for hostile
environments.
But when was the last time you ran from a predator? In modern times,
with an overabundance of food and safe living conditions, many people
have accumulated an excess storage of fat. In fact, more than one-third of the adult population in the United States is obese.
The major problem with this excess fat is that the fat cells,
called adipocytes, do not function normally. They store energy at an
abnormally high rate and release energy at an abnormally slow rate.
What’s more, these extra and enlarged fat cells produce abnormal amounts
of different hormones. These hormones increase inflammation, slow down
metabolism, and contribute to disease. This complicated pathological
process of excess fat and dysfunction is called adiposopathy, and it makes the treatment of obesity very difficult.
A fat cell is loaded with triglycerides, or fatty deposits, and does not resemble other cells in our body.Pavel Chagochkin/Shutterstock.com
When a person begins and maintains a new exercise regimen and limits
calories, the body does two things to “burn fat.” First, it uses the
energy stored in the fat cells to fuel new activity. Second, it stops
putting away so much for storage.
The brain signals fat cells to release the energy packages, or fatty
acid molecules, to the bloodstream. The muscles, lungs and heart pick up
these fatty acids, break them apart, and use the energy stored in the
bonds to execute their activities. The scraps that remain are discarded
as part of respiration, in the outgoing carbon dioxide,
or in urine. This leaves the fat cell empty and renders it useless. The
cells actually have a short lifespan so when they die the body absorbs
the empty cast and doesn’t replace them. Over time, the body directly
extracts the energy (i.e., calories) from food to the organs that need
them instead of storing it first.
As a result, the body readjusts by decreasing the number and size of fat cells, which subsequently improves baseline metabolism,
decreases inflammation, treats disease, and prolongs lives. If we
maintain this situation over time, the body reabsorbs the extra empty
fat cells and discards them as waste, leaving us leaner and healthier on
multiple levels.
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