It may surprise you to know that, for many people, Type 2 diabetes is primarily a liver disease. The pancreas damage comes later. Is there anything we can do to heal a diabetic liver?
Liver issues in diabetes are complicated. An article in the journal Clinical Diabetes explained that diabetes can cause liver disease; liver disease can cause diabetes; or both can arise together from other causes. Whichever comes first, the sick liver may produce way too much glucose, enough to overwhelm the body’s insulin.
Why would a liver start pumping out unneeded glucose? Unhealthy livers tend to have a lot of fat in them, a condition called nonalcoholic fatty liver disease, or NAFLD.
You don’t have to be fat to have a fatty liver (although overweight and obesity are risk factors). Thin people get it too, and the causes of NAFLD are unknown. Some are thought to be genetic. However, a recent animal study published in the journal PLOS One found that prenatal exposure to alcohol (from a mother who drank while pregnant) is strongly associated diabetes-like glucose production by the liver. There are probably other causes as well, including environmental chemicals and possibly unhealthy diets.
A rat study in the Journal of Biological Chemistry found that fatty livers became more resistant to insulin. The researchers found processes by which insulin normally tells the liver to stop producing unwanted glucose. Excess fat in the liver seemed to block these processes, so too much glucose was produced.
Human livers apparently act the same way. An Italian study in The American Journal of Medicine found that subjects with NAFLD had high fasting and postmeal insulin levels, high insulin resistance, and high triglyceride levels. (Triglycerides are a kind of blood fat.) High insulin levels can be a cause or a result of insulin resistance.
Again, these Italian subjects were not necessarily fat or obese. They just had fatty livers as shown by ultrasound.
How the liver raises blood glucose
I thought that diabetic livers caused high blood glucose levels by breaking down stored starch (glycogen) into glucose, but the reality is different. The liver actively creates brand new glucose out of proteins and fats, a process called gluconeogenesis, or GNG. People with diabetes tend to have far more GNG, so they produce much more glucose.
GNG is a fascinating process. Without it, we would all be dead from low blood glucose while sleeping or when missing some meals. According to Wikipedia, GNG is “generation of glucose from non-carbohydrates…such as pyruvate, lactate, glycerol, amino acids, and odd-chain fatty acids.”
Ruminant animals like cows and sheep get much of their energy from GNG. But in humans, out of control GNG is a major concern in diabetes.
In 2011, Web Editor Diane Fennell reported on Diabetes Self-Management that excess levels of a protein called FOX06 in the liver lead to inappropriate release of glucose. Study author H. Henry Dong, PhD, wrote that “Glucose overproduction in the liver is a major contributing factor for high blood sugar in diabetes, Type 1 and 2.”
So is fatty liver the same as Type 2 diabetes, or the main cause of it? It’s not so simple, because many with fatty liver do not get diabetes, and many with diabetes may not have fatty livers. An article in the American Journal of Physiology reported that increased glucose production usually appears only when insulin levels are low. They also found that high insulin resistance in the muscles “contributes as much or more to glucose elevations” as high GNG does.
I should also mention the effect of glucagon. Glucagon is the anti-insulin. It tells the body to break down fat, starch, and protein and make more glucose. If your liver is exposed to too much glucagon, it can overpower the insulin.
So it appears that what we call “Type 2″ is really several different diseases. One is mostly caused by the liver overproducing glucose; another by insulin resistance in the muscles. Still others seem to result from damage to the pancreas or the signaling systems the body uses to direct insulin. Of course, more than one of those is usually going on.
Can we help our livers?
Is there anything we can do to fix livers that leak glucose? The drug metformin is the most-used way. It seems to replace insulin in telling the liver to hold on to glucose. Reader Jim Snell has told us he corrected chronically high blood glucose levels by taking metformin five times a day — with each meal, at 10 PM, and midnight. Skipping even one dose sends his glucose level back up.
Unfortunately, not everyone can take metformin because of the side effects. And even if it works, it’s not a cure. You have to stay on it, possibly for life.
Former Editor Tara Dairman reported here in 2008 that exercising regularly “significantly reduces the amount of fat in and around the liver.”
The liver is generally pretty good at healing itself. In the 600-calorie-a-day-diet study from England in 2011, and in other studies, MRIs showed that most participants’ livers quickly lost all excess fat and started functioning normally again. But we don’t know how long that benefit lasted after the end of the study.
The herbs milk thistle, dandelion, and bitter melon, as well as vinegar, are often used to help livers heal. We know bitter melon and vinegar are good for blood glucose levels. Diet and exercise can make a difference. Vegetables like broccoli, collard greens, and kale, and small fish like sardines are often recommended. An article on Livestrong.com suggests vitamin B complex, vitamin C, and coenzyme Q10 for liver health.
I wish I had more, but that’s all I found. I’d start with the bitter melon or vinegar.