Fat is (ironically) active in your body

You might think fat just sits there on your body. Sedentary, immobile, inactive - much like the behaviors that spawned it, lol. But turns out, fat (adipose tissue) is far from an inactive space filler in your body. It's actually considered an endocrine organ, meaning it releases proteins (adipokines) that have a biological effect! Fat (adipose tissue) is made of fat cells (adipocytes), immune cells (infiltrated macrophages), connective tissue (stromal cells) and nerve tissue. These integrated units send signals to talk to nearby body cells, and tell them what to do. This cell-to-cell signaling over short distances is called paracrine signalling.

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Back up. What kind of biological effects are we talking about here? Well, the signals emanating from fat tissue have a role in the following:

• Body weight regulation
• Insulin resistance: A trademark sign of type 2 diabetes.
• Alteration in lipids: Blood lipids are fatty acids and cholesterol. High levels is bad for your heart.
• Blood pressure: High blood pressure (hypertension) overworks your heart.
• Coagulation: Blood clotting.
• Fibrinolysis: A process that prevents blood clots from growing and becoming problematic. 
• Inflammation: Short-term inflammation is helpful to rid your body of foreign substances or heal injuries. But with chronic inflammation, your immune system "soldiers" end up attacking healthy tissues.

When you mess with the above list, it puts your body on the path towards:

• Oxidative stress: This is when the harmful by-products (free radicals) of normal body processes (e.g. energy metabolism or detox reactions) outnumber the antioxidant defenses that remove them. 
• Endothelial dysfunction: This is when the inner lining of your blood vessels is not doing it's job. That job entails constricting/dilating blood vessels, preventing blood clots, allowing the proper amount of fluid and electrolytes to pass from your blood to your tissues, and assisting in the body's immune response. 

Oxidative stress and endothelial dysfunction result in:

• Atherosclerosis: This is a build up of plaque in the arteries. If a piece of plaque breaks free (ruptures), it can become lodged in a blood vessel. This could cause a blood clot (thrombus) that can eventually block blood flow to the heart (heart attack) or brain (stroke). 

The moral of this story is that fat, especially abdominal fat (visceral fat, intra-abdominal fat), has biologically detrimental effects on heart health. As such, losing weight brings more than just superficial perks. To improve your cardiovascular health, follow the nutritional road map pictured below. Pair these diet recommendations with at least 30 min of daily physical activity. Your ticker will thank you.