Alzheimer's disease and the insulin resistance

    For years it was hypotethised that there is a link between diabetes and Alzheimer's disease. But, as the latest researches point out, both illnesses got something in common: poor blood sugar management and insulin resistance. Despite the sugar being present in almost everything we eat or drink (yes, even bread, yogurts, cereals, you name it, it is there), our body tolerance for sugar is somewhere around 15-20 grams of single carbohydrates per day. Per day, i said, and keep in mind that just one energy drink with reduced sugar has 24 grams of it. There is also the not so well explained issue about high and low glycaemic index foods. Let's start with this first. 

    The higher the glycaemic index is (do not think only about sugar, the starch also has something to do with this - white bread, white rice, potatoes, baking goods) the larger amounts of insulin our pancreas will secrete into the bloodstream, to lower the blood sugar. If this happen too often, our cells will start to resist to the insulin signalling too much blood sugar, in the same way you got used in a very noisy environment (eventually). The noise is there (blood sugar in our case), but   you stop reacting too it. And a high level of blood sugar is damaging our body in so many ways. (Find more about this in this article).

    Well known effects of the insulin resistance are type 2 diabetes, fatty liver, metabolic syndrome, but also AD (Alzheimer's disease). There are many pathways that are affected by the insulin resistance. To start with the insulin binding to the insulin receptors, triggering the survival of the neurons, you can only imagine what will happen if this trigger is drastically decreased by the high insulin levels, present most of the time in our bloodstream. Another way to mess up with our nervous system is via the insulin-degrading enzyme (IDE) used to get rid on the insulin, but, surprise, also used to get rid of the amyloid beta (one of the main issues in AD). Because, as we know already, higher levels of amyloid-beta equals full blown AD. 

    As the insulin resistance is just a result, the cause being chronically high blood sugar levels, let's see how this is wreaking havoc in our body. The glucose can attack easily to many proteins, interfering with their usual functions. The common blood test to check diabetes called HbA1c is measuring one of these overused proteins - hemoglobins changed to produce advanced glycation end products (AGE). As these proteins trigger our immune system, raising inflammation (one of the risk factors in AD), they are also binding to their own receptor (AGE receptors of RAGE), triggering inflammation even further. Shall we add to the list? Yes, there is more, AGE molecules form free radicals, which in turn can damage almost anything they touch, even DNA and any cell membranes. The additionally damage the blood vessels (less nutrients to go to the brain) and negatively alter the blood-brain barrier. 

    The main blood tests to monitor these risk factors are fasting insulin level (ideally 4.5 microIU/ml or less), the HbA1c test (ideally under 5.6%) and the fasting glucose ( ideally between 70-90 mg/dl, but not more than that). 

    How you manage this? Learning about diabetes management is a good idea, as everything that is recommended for a type 2 diabetes, it will also work for healthy individuals or pre-diabetes condition. 

Next issue to tackle will be inflammation, as i started to explain a bit of its mechanisms today. 

How to avoid getting fat in few easy steps (part 1)

This is a story of love, a Valentine's Day special, the story of interdependence and attachment between two main macro-nutrients, let's call them carbohydrates and fats.

Carbohydrates can be simple and complex. The simple ones can be classified in monosaccharides (glucose, fructose and galactose) and disaccharides (maltose, sucrose and lactose). The complex ones are glycogen, starchi and fibers.

During digestion, the starch is broken to same degree, under the action of the amylase enzyme, secreted by salivary glands. When the carbohydrates reaches the stomach, the amylase is inactivated by the acidic medium. The digestion continues in the duodenum, under the action of the pancreatic amylase (an enzyme secreted by the pancreas). The starch is broken in maltose, sucrose and lactose. They are transformed in fructose, glucose and galactose under the action of enzymes such as maltase, sucrase and lactase).

Absorbed in the blood stream, the monosaccharides (glucose, fructose and galactose) are then processed in the liver, where almost all the fructose and galactose is used, and a big part of the glucose goes back in the blood stream, in direct relation to the blood sugar level (glucose level).

When glucose level goes up, the pancreas is secreting the insulin hormone, the role of insulin being to transform the glucose from the blood stream into glycogen, and to deposit the glycogen into the muscle and in the liver. After this process the blood sugar level is decreasing. Because of this action, the pancreas is secreting another hormone called glucagon, to break the glycogen from the liver into glucose, and when the liver deposit is finished (for example during a period of fasting), the glycogen from the muscle is used. The glycogen deposit from the muscle it is also used to generate energy when we are exercising. If we finish both of them (the deposits from muscle and from liver), the muscle is used for glycogen and we lose weight.

If both the deposits are up to 100%, the glucose is transformed into fat. But the fat is never transformed back into glucose.

Conclusions:

Fasting and exercise are helping us to deplete the glycogen deposits, so the glucose will not be transformed in fat. (Search on Google about intermittent fasting)

If we fast and exercise too much, we will lose weight (but this will be muscle weight and not fat weight).

It is possible to eat plenty of sweets, as long as you are having a fasting period right before/after, or you exercise, or both. (This is by far my favourite conclusion)


(More to come soon - this is an excerpt from the future second edition of the book The Macronutrients Pocket Guide, written by me, of course )

Take care of your glycogen deposits,
G.