Treating Alzheimer's With Insulin

Alzheimer's disease used to be a very rare condition. Type 2 diabetes also used to be a very rare condition. As type 2 diabetes has become more and more common, however, Alzheimer's disease has also become more and more common. Some commentators have even gone so far as to label Alzheimer's disease as "type 3 diabetes," caused by nothing more than blood sugar levels that have been kept too high for too long. It's really not quite that simple, but controlling diabetes may also lead to better brain health in old age.

What Is The Real Role Of Insulin In The Brain?

What Has Insulin Got To Do With Alzheimer's?

Insulin And Amyloid

Brain cells can break down insulin that they cannot use. However, when they do that, they don't have enough enzymes left over to break down a protein called amyloid. This is the protein that makes "tangles that strangle" neurons and causes Alzheimer's. If your body makes too much insulin, then your brain can't get rid of the protein that is (almost always) associated with Alzheimer's.

Using Insulin to Manage Brain Diseases

If too much insulin is a major contributing factor to Alzheimer's disease, then how can you possibly prevent Alzheimer's disease? The answer, oddly enough, is to give insulin.

When insulin is injected (whether the user is diabetic or not) or a powdered form of insulin is snorted up the nose, the brain gets a "hit" of insulin that helps it absorb the sugars and proteins it needs and hang on to the fats it needs. The pancreas doesn't have to make that extra little bit of insulin, so it doesn't dump more and more and more insulin into the bloodstream to prevent "brain fog" and to deal with loss of appetite control. The net result is less insulin resistance, which means that over the long run, the brain doesn't have to break down as much insulin, so it can remove the amyloid proteins that seem to cause Alzheimer's disease. 

Treating type 2 diabetes with actual injected insulin, and never using drugs that force the pancreas to make more insulin (such as sulfonylurea drugs, including Amaryl, Glucotrol, or Micronase, or their generic forms glimepiride, glipizide, glyburide), may protect the brain from changes that lead to Alzheimer's disease. Drugs that help insulin receptors work better like metformin also protect the brain. The newer insulin sensitizers such as liraglutide (Victoza) may also be beneficial to the brain. It's not just Alzheimer's disease that may benefit from this approach.

Many Brain Diseases May Benefit From Insulin Management

Researchers have also started looking into the use of insulin as a treatment for bipolar disorder. There is believed to be a strong link between type 2 diabetes and post-traumatic stress disorder, the more insulin resistant you are, the more likely you are to develop PTSD. Insulin resistance and type 2 diabetes have also been linked to delirium, binge eating disorders (that is, diabetes causes binge eating, not binge eating causes diabetes), depression, anxiety, addiction, insomnia, and schizophrenia.

If Insulin Resistance Is The Problem, What Is The Solution?

• Avoid overeating (ever). Your body has to produce extra insulin to cover blood sugar increases after a large meal. That extra insulin has to be broken down in your brain at the expense of breaking down amyloid proteins.
• Embrace physical activity. Hard exercises are actually what help you the most to overcome insulin resistance. When you push muscles to their limits, they have to use 50 times the normal amount of insulin to import the amino acids they need to grow even more muscle. That's insulin that doesn't go to your brain.

• If you have diabetes, pay careful attention to your blood sugar levels. If you can keep your blood sugar levels sufficently well controlled that your HbA1C is 7.0 percent or lower (corresponding to an average blood sugar level of about 170 mg/dl or 10 mmol/L), you lower your risk of Alzheimer's by 80 percent.