What are glucotoxins or advanced glycosylation end products (AGEs)? What health risks can they pose? How can we avoid them?
Without getting too technical, we can say that advanced glycosylation end products (AGEs) are harmful compounds formed when simple sugars, such as glucose in the bloodstream, attach to a free amino acid of a protein, a lipid or DNA without the intervention of enzymes.
This process is called non-enzymatic glycosylation and is often referred to as the Maillard reaction.
Since it is not an enzymatic process, it is spontaneous and undesirable. Moreover, due to the addition of sugars to proteins, non-enzymatic glycosylation is a type of protein damage, as it reduces both the stability and functionality of proteins.
THE HEALTH EFFECTS
There are two sources of glucotoxins: endogenous and exogenous.
Normally, endogenous glucotoxins are formed slowly and throughout life, gradually increasing with age, although factors such as hyperglycaemia and hyperlipidaemia accelerate it.
Nevertheless, our body has mechanisms for their elimination. Which means that only at a certain point can non-enzymatic glycosylation be harmful.
However, advanced glycosylation end products can also be formed exogenously, i.e. outside the body, for example in our food, when the conditions are right for the corresponding chemical reactions to take place.
Consumption of exogenous glucotoxins appears to be an important contributor to the concentration of advanced glycosylation end products within body tissues where they become structurally and functionally indistinguishable from endogenous ones.
Which means that with continued intake, eventually the glucotoxins build up beyond the point where the body can continue to eliminate them.
The accumulation of AGEs adversely affects almost every type of cell and molecule in the body, having roles in the development, progression and exacerbation of many diseases such as infertility, ο diabetes, η atherosclerosis, the cardiovascular diseases, η kidney disease, η macular degeneration and the Alzheimer's disease. And since we know that they increase with age, we can say that they also contribute to in old age.
Even worse, detoxification processes either slow down or tend to weaken when we are sick, causing these molecules to build up. So, as their elimination from the body slows down, a vicious cycle is created.
GLUCOTOXINS IN FOOD
Here we have bad news.
The Maillard reaction, the chemical reaction responsible for creating the final advanced glycosylation products, in order to take place outside our body requires the food to have simple sugars, protein and to be treated with a source of dry heat (or long storage in a dry environment). The result is a change in the colour of the food to darker, the smell to more pleasant and the taste to more palatable.
In short, anything that is barbecued, grilled, skewered, sautéed, fried, toasted, flame broiled, as well as foods in the oven, crock pot and pressure cooker in which there is not enough water to cook the meat through boiling will have AGEs.
It's a difficult situation, don't you agree? We have worse. The memorandum is simple: Dry heat, change of color and taste.
To help you understand when advanced glycosylation products are finally produced, I will give some examples:
- UHT milk, as it is processed at a temperature capable of producing AGEs (but not single pasteurisation milk)
- Pasta from large factories using high temperature methods to reduce production time
- Processed meat
- The bread, although it will have additional AGEs on its own because it is made via a dry heat source, when toasted it will have additional AGEs
- High-fat and cured cheeses
- Smoked salmon
- Nuts and nuts
Let me stress here that this is not a list of foods with the highest content of advanced glycosylation products, but examples of when and under what conditions these can be formed, so that you know for yourself how they are formed so that you can avoid them.
LIST OF FOODS WITH GLUCOTOXINS
Below is a list of more than 500 foods and their content of advanced glycosylation products. Note that the serving size varies from food to food (e.g. kU per 100g and kU per 100ml) and that you will need to adjust depending on the food and the amount you consume (e.g. 100g Big Mac is 7,801kU/100g, but Big Mac weighs about 215g, so a Big Mac will have about 16,772kU).
Now that we know how glucotoxins are created and which foods have the highest levels, it's time to learn how to avoid them.
- The daily intake of glucotoxins in healthy people ranges from 4000 up to 24,000 kU/day.
- A diet low in AGEs is considered one that provides up to 15000kU/day.
- Meats, high sugar/fat foods and highly processed foods are likely to develop high levels of advanced glycosylation end products.
- High temperatures, low humidity and alkaline pH contribute to the formation of new AGEs. In contrast, lower temperatures, high humidity and low pH contribute little to the formation of glycotoxins.
- Buy a steam cooker and try to eat from it as often as possible, instead of the dry heat methods mentioned.
- You prefer to make poached, boiled, steamed and stewed foods.
- Milk, yoghurt, fruit and vegetables have lower levels of AGEs. Put them in your diet so that naturally the amount of foods that eventually provide advanced glycosylation products will drop.
- Try to avoid products on the list with high glucotoxin content.
- But, as is always my advice, it's one thing to try to avoid certain foods, it's another to suppress yourself. This behavior can make you lash out and ultimately have the opposite effect. Everything in moderation.
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