We used to think that our fat cells were just storing extra calories for later use: lots of tiny energy-holding tanks! Then we discovered that some fats cell are metabolically active; that is, they produce chemicals, including hormones, that affect how our general biochemistry works.
Our belly fat cells can make inflammatory cytokines. These then travel throughout the body, creating generalised inflammation. Some research suggests changes in how fat is stored may contribute to inflammation, as can an unhealthy microbiome. The biochemistry of this is not simple, nor fully understood.
Surprisingly belly fat also makes cortisol: the stress hormone that reduces inflammation. We need cortisol to help us deal with stress and infection, but too much for too long starts to work against our long term optimal health, because cortisol:
• Increases blood pressure
• Increases blood sugar levels
• Increases cravings for sweet, fatty and salty foods
• Causes fat to be stored around our organs (belly fat)
• Reduces inflammation
• Suppresses the immune system
• Increases blood fats
• Adversely affects the balance of “good” and “bad” cholesterols
Now, cortisol comes in two forms:
Cortisone - which is relatively inactive
Cortisol - which is far more metabolically active
It is useful for our bodies to have cortisol available in a form that is ready to activate quickly, when it is needed to react to a sudden stressor, rather than having to take time and energy to build the molecule from scratch.
Belly fat cells are different from other fat stores in your body: they have four times as many receptors for cortisone and cortisol! And they contain an enzyme that converts cortisone to the more active cortisol, so having belly fat tends to increase cortisol production. Paradoxically, cortisol tends to increase belly fat: a vicious cycle that helps perpetuate this syndrome.
A prolonged or exaggerated stress response can trigger and sustain cortisol dysfunction, so the cortisol produced is no longer as effective at doing its job against generalised inflammation. The signs and symptoms known to be associated with this increased inflammation are:
• Carrying excess fat around the waist (apple vs pear shaped body)
• High blood pressure
• High blood sugar levels
• High blood fats
• Low “good cholesterol” levels
Metabolic syndrome is diagnosed when someone has 3 or more symptoms on this list, although the exact combination of defining factors is still under discussion in the medical community, and may be refined over time.
The term "metabolic" refers to the biochemical processes involved in the body's normal functioning. A syndrome is a group of symptoms that consistently occur together. So Metabolic syndrome means that a group of biochemical processes are deviating from normal, all at the same time. This is because the changes are all responses to the same underlying biochemical problems.
Why Does It Matter to Me?
In general, a person who has metabolic syndrome is twice as likely to develop heart disease and five times as likely to develop diabetes, as someone who doesn't have metabolic syndrome, and they are very likely to have a fatty liver. Metabolic syndrome is so common, with estimates that at least 25% of people in North America have it, and we know prevalence increases with age. So if you don’t have it, it is very likely that someone you know has it.
We all know that the problems that constitute metabolic syndrome are major health problems in the modern world, and that they are things we can really improve for ourselves with the diet and lifestyle changes that SHINE encourages.
Watch this space for more on metabolic syndrome, blood sugar problems and insulin resistance, and very importantly, ways to avoid them or turn them around!