Today we are going to talk about how your genetics are
sometimes against you and your weight, but why?... Well Obesity and genetics a
directly related and combines with some environmental influences they are 70%
responsible for your body’s weight.
And here at Long Term WLS / VSG we understand that bariatric
surgery may be the only way to effectively alter these genetically
predetermined body processes.
But why my genes are
causing me obesity?
Evolution yeah that’s it evolution is one
of the main reasons. We are designed to survive and that’s how our bodies has
been adapting itself going through survival
requirements have coincided with environmental factors over the course of human
history.
Let’s stop the history lesson for a moment
and go back to what happens internally and let’s talk about hunger. Your genetics determine
the amount of hunger-causing hormones that are secreted by your body into your bloodstream and how your brain interacts with those hormones.
Three types of internal body secretions have been found to regulate hunger:
- Hormones from the digestive
system, including ghrelin, peptide YY and GLP-1, let your brain know when
more nutrients are “needed” based on your body’s requirements.
- Hormones from fat cells
(“adipocytes”) such as leptin keep your brain informed about your body’s
level of energy deposits (fat cells).
- Neuropeptides in the brain regulate food intake by responding to
signals from hormones secreted by the body.
Ghrelin
is the first of three hormones sited most frequently in conjunction with
obesity. When your stomach is empty, ghrelin is secreted into your blood stream
by your stomach. After you eat, the amount of secreted ghrelin drops, then
slowly rises until your next meal. Lower ghrelin means less hunger.
Neuropeptide
Y neurons in the brain are activated by ghrelin. When your blood carries more
ghrelin to the brain, your neuropeptides create “hunger signals” leading you to
feel hungry and eat.
The third most commonly-referenced hormone associated
with obesity is leptin, which is secreted by fat cells!
If dieting has
not worked for you, ghrelin, peptide YY and leptin are likely to be a few of
the main culprits because as you diet…
- The amount of ghrelin your stomach secretes increases, causing your
brain to receive more hunger signals.
- The amount of peptide YY your digestive system secretes decreases,
causing you to feel hungrier.
- As your leptin-secreting fat
deposits dissolve, less leptin is released into your blood causing your
brain to want to eat more in order to restore its fat deposits.
Now to complete the cycle you have to know that your
weight also has an important role here. Each
of our bodies has a set weight that it “wants” to maintain. If your body weight
goes above your set point, your metabolism will speed up in an attempt to burn
off the excess weight. If your weight falls below your set point, your
metabolism will slow down to allow more fat accumulation.
Now
we that we know how genetics affect let’s talk about how weight loss surgery
helps. Let’s keep it in two ways:
1.
Hormones and weight loss: surgery impacts the hormones that affect hunger
2.
Metabolism and weight loss: surgery increases the body’s fat-burning metabolism
Surgeries that bypass or remove part of the stomach,
including gastric bypass surgery, gastric sleeve surgery and duodenal switch surgery may reduce feelings of hunger by…
- Reducing the level of ghrelin secreted into the blood stream by the
stomach
- Increasing the level of peptide YY secreted into the blood stream by
the lower digestive system
Ghrelin and peptide YY plasma
(blood) levels are unchanged after lap band surgery (gastric banding)
and vertical banded Gastroplasty surgery.
Therefore, it could be suggested
that the procedures that remove or bypass part of the stomach (i.e. gastric
bypass, gastric sleeve and duodenal switch) could aid in long-term weight loss
by causing patients to feel less hungry. At a minimum, sustained weight loss
should feel easier to
achieve after these procedures due to fewer hunger signals reaching the brain.
Also bariatric surgery has been shown to increase glucose metabolism
causing the body to burn energy (fat) more quickly. Increased metabolism is the
result of and directly proportionate to the amount of fat lost after weight
loss surgery...
