You can often tell if people have diabetes just by looking at them. A person with a big belly and small buttocks is at very high risk for being diabetic, because those who store fat primarily in the belly are most likely to also store a large amount of fat in the liver. Having excess fat in your liver markedly increases risk for diabetes and heart attacks (JAMA, 2017;317(6):626-634), and also increases all markers of inflammation that are associated with increased risk for heart attacks (Clinical Gastroenterology and Hepatology, February 28, 2019). You can reduce the amount of fat in your liver and the inflammation it causes by severely restricting sugared drinks, fruit juices and foods with added sugars (JAMA, Jan. 22, 2019).
How a Fatty Liver Leads to Diabetes
Your blood sugar level rises after you eat, but to prevent it from rising too high, your pancreas releases insulin which is supposed to lower high blood sugar levels by driving sugar from the bloodstream into the liver. However, if your liver is full of fat, the excess fat prevents the liver from accepting the sugar and blood sugar levels can rise even higher (Eur J Gastroenterol Hepatol, Dec 2016;28(12):1443-1449).
The leading cause of fatty liver used to be alcohol, but now it is far more commonly caused by drinking sugared drinks and eating sugar-added foods. The simple sugar, fructose, is the most likely food component to end up as fat in your liver (Dig Dis Sci, May 2016;61(5):1282-93). A fatty liver comes from:
• high rises in blood sugar, which cause
• high blood insulin levels that
• convert blood sugar to a type of fat called triglycerides, and
• insulin drives triglycerides primarily into the fat cells in your belly and its organs such as your liver.
Having high triglycerides and a fat belly are signs of high blood insulin levels, and having high blood levels of insulin increases risk for heart attacks. Insulin also acts on the brain to make you eat more, on your liver to manufacture more fat, and on the fat cells in your belly to store that fat. People who store fat primarily in the belly have higher blood insulin and blood sugar levels, which raise LDL (bad) cholesterol and lower HDL (good) cholesterol.
Having a normal fasting blood sugar level does not rule out diabetes. A high rise in blood sugar after meals can damage every cell in your body. If your blood sugar level one hour after eating is greater than 140, your cells are being damaged and your life is being shortened (Atherosclerosis, Jan 2017;256:15-20).
Why Sugared Drinks Cause the Highest Rises in Blood Sugar
When you take in liquid sugar, you get a much higher rise in blood sugar than when you take in the same amount of sugar in a solid food. Solid food is not allowed to pass into your intestines because when you eat, the pyloric muscle at the end of the stomach closes and allows only a liquid soup to pass into the intestines. Sugared drinks can pass right through into your intestines, so they cause the quickest rises in blood sugar. Compared to sugar in food, sugared drinks are more tightly associated with increased risk for excess belly fat (Circulation, January 11, 2016; Quart J Med, Apr 26, 2017).
All sugared drinks are associated with increased risk for developing a fatty liver, pre-diabetes (metabolic syndrome), diabetes, inflammation, abdominal obesity, high triglycerides, and increased waist circumference (Int J Clin Pract, Jan 10, 2017; J of the Acad of Nutr and Dietetics, Feb 2013;113(2):219-227; Am J of Clin Nutr, March 23, 2011).
What Can You Do About a Fatty Liver?
Your doctor can order a liver sonogram to see if you have excess fat in your liver (Nutrition, Metabolism & Cardiovascular Diseases, Dec 30, 2015).
Diabetes can be treated and often cured with a diet that removes fat from the liver (Diabetologia, 2011 Oct; 54(10): 2506-2514) and with exercise that removes excess fat from the liver and muscles (Scandinavian Journal of Medicine & Science in Sports, March 13, 2017;27(5)).
Diet: Avoid the foods that cause high rises in blood sugar, especially sugared drinks and sugar-added foods, and restrict other refined carbohydrates. Restrict red meat and processed meats, which block insulin receptors (JAMA Intern Med, 2013;173(14):1328-1335), and fried foods.
Exercise: Resting muscles draw almost no sugar from your bloodstream and the little that they draw requires insulin to do so. On the other hand, contracting muscles draw tremendous amounts of sugar from the bloodstream and don’t even need insulin to do so. This effect that exercise has of rapidly drawing sugar from the bloodstream is maximal during exercise and for up to an hour after you finish exercising, and rapidly tapers off for about 17 hours. Then the resting muscles can draw sugar only with insulin (Am J Clin Nutr, 2008(July);88(1):51-57). Exercise can reduce liver fat even if a person does not lose weight (Metabolism, Mar, 2017;68:119-132).
• If you have a big belly or your blood sugar is greater than 140 one hour after a meal, I recommend that you lose weight (if overweight) with intermittent fasting; check with your doctor.
• Since most liver fat comes from sugar, avoid or severely restrict all sugared drinks and sugar-added foods.
• Restrict other refined carbohydrates such as foods made from flour (bakery products, pasta, many breakfast cereals and so forth).
• Restrict red meat, processed meat and fried foods.
• Eat plenty of vegetables, seeds and nuts which are rich sources of soluble fiber.
• Try to exercise every day.
Caution: Intense exercise can cause heart attacks in people who already have blocked arteries. Check with your doctor before starting an exercise program or increasing the intensity of your existing program.