North America's epidemic of obesity, diabetes and heart attacks appears to be fueled by:
• storing fat in the liver, muscles and around organs, rather than just in fat cells,
• excess calories,
• sugar added to foods and drinks and
• lack of exercise.
Where you store fat is determined by genetics and the types of food that you eat. When you take in more food than you burn, the extra calories are converted to fat and are stored in fat cells. Full fat cells release a hormone called leptin that travels to your brain where it is supposed to make you feel full so you stop eating. Leptin also drives fat into your mitochondria in cells to be used for energy (Nature, 2002;415:339–343).
However, eating and drinking lots of sugar specifically causes fat to be deposited in your belly, liver and muscles (Quart Journ Med, Sep 18, 2015), which do not produce leptin so your brain does not send messages that you are full. You keep on eating food that you do not need and storing even more extra fat in your liver and muscles. You can tell if this is happening to you just by standing in front of a mirror. If you have a big belly and small buttocks, you store most of your fat in your liver and muscles. Your doctor can order a sonogram of your liver that will show the stored fat there (Nutrition, Metabolism & Cardiovascular Diseases, 12/30/2015).
Why Excess Fat in Your Liver is Dangerous
A high rise in blood sugar causes sugar to stick to the outer membranes of just about every cell in your body. Once there, sugar can never get off a cell and it is eventually converted to sorbitol that destroys the cell. This cell damage causes all of the horrible side effects of diabetes.
To protect you from a high rise in blood sugar after eating, your pancreas releases insulin which lowers blood sugar by driving sugar from the bloodstream into your liver. However, as your liver keeps filling up with fat, it loses its ability to accept the sugar from your bloodstream and the high sugar level in your bloodstream then causes damage to every cell in your body, plaques to form in your arteries and even more fat to be deposited in your liver.
Excess Fat in Your Muscles
Your fat cells usually fill up long before fat goes to your muscles and liver. Your liver tries to convert all extra sugar rapidly to a type of fat called triglycerides. When muscles, liver and fat cells are full of fat, most of the extra sugar is converted to triglycerides. Then your liver takes about 1500 triglyceride molecules, combines them with a lesser number of cholesterol molecules to make VLDL cholesterol that eventually encourages plaques to form in arteries to increase your risk for a heart attack. The excess sugar in your blood also has no place to go. As blood sugar levels go even higher, sugar damages the DNA genetic material in cells to increase risk for cancer.
Your muscles also help to control blood sugar levels, but only when you exercise. Resting muscles draw almost no sugar from your bloodstream, and the little that they do draw requires insulin (Am J Clin Nutr, 2008(July);88(1):51-57). However, contracting muscles draw huge amounts of sugar from your bloodstream and don't even need insulin to do so (J Appl Physiol, 2005;99: 338-343 & 2005;8750-7587). Even sitting on a motor driven stationary bicycle that passively moves your muscles also allows them to take in sugar without needing insulin (Med Sci Sports Exerc, April 6, 2016). Any regular exercise empties muscles of extra fat and therefore helps them turn sugar and fat into energy, rather than storing more fat in your body to increase your risk for a premature death.
The benefit of exercising muscles drawing sugar into muscles without needing insulin is maximized while you exercise and for up to an hour after you finish exercising. The effect disappears completely after about seventeen hours, so I recommend that you exercise every day.
If you store fat primarily in your belly, or if you come from a family with large bellies, you are at increased risk for muscles and liver to fill with fat so you may be less able to control blood sugar levels efficiently. You need to be particularly careful to avoid sugar-added foods and drinks as well as other refined carbohydrates (foods made from any kind of flour).