One of the potential consequences of having high levels of belly fat is increased blood pressure. Since two thirds of people over 45 years are either prehypertensive or have hypertension, there are many people for whom a pressure increase is unhealthful. Having lots of belly fat causes an inflammatory response. One part of the body that becomes inflamed is the lining of blood vessels, which is turn results in increased blood pressure.
Most people know that having a big belly in combination with thinner arms and legs is bad. Studies have shown that having a big belly is worse than being overweight but having the fat more evenly distributed.
So what is it about belly fat that is so bad? Belly, also called visceral, fat is the type of fat we have round our abdominal organs to protect them. We all need to have some visceral fat for protection. The other type that covers us is called subcutaneous. These two types of fat are not the same and have some different characteristics. For instance, they express some different genes. Additionally, when there is a large amount of belly fat, lots of macrophages are found mixed in with the fat cells.
Macrophages are cells of the immune system; they play an important role in scavenging dead cells and mounting an immune response against bacteria and other pathogens. When they are active macrophages put out a lot of substances that cause immune responses including inflammation.
When there is an increased amount of belly fat, the high number of active macrophages, results in high levels of inflammatory substances throughout the body including the blood. This leads to the whole body being at a low level of continual inflammation, including the layer of endothelial cells. This inflammation over time causes dysfunction of the endothelial cells.
The improper endothelial cellular functioning has several negative effects including contraction of blood vessels, which causes the interior of the vessels to become narrower. When blood vessels constrict blood pressure increases. Think of when you just squeeze the end of a hose, the narrowing of the end causes the water to come out with more force at higher pressure. If you could squeeze the whole hose, the pressure would be higher throughout the length of the hose.
In summary: High levels of belly fat cause chronic inflammation. The continually inflamed endothelial cells that line blood vessels do not function properly. One consequence of this dysfunction is constriction of blood vessels, which is a major contributor to increased blood pressure.
A big belly, if you already have hypertension can increase blood pressure further and make it more resistant to treatment. If you are borderline prehypertensive or hypertensive, you may get pushed over the border. Reducing your waist measurement is another way to lower blood pressure.
Judith Airey PhD. is a biomedical researcher with a range of interests including all things cardiovascular. She has several health-related websites including a blood pressure information site http://www.infobloodpressure.com/ and a blog http://www.lifeagingand.com/