What Are AGEs (Advanced Glycation End Products)?

Advanced glycation end products (AGEs) are harmful molecules formed by the glycation and oxidation of lipids and proteins. AGEs are formed in your body by your metabolism.

Advanced glycation end products (AGEs) are harmful molecules formed by the glycation and oxidation of lipids and proteins. Glycation is the process of combining other molecules with sugars. Oxidation is the process of combining other molecules with oxygen. 

AGEs are formed in your body by your metabolism, but the major source is probably your food. AGEs combine with receptors located on blood vessels and several other organs to cause damage to organ systems.

AGEs (also known as glycotoxins) are harmful molecules formed in your food by grilling, toasting, roasting, broiling, frying, and other high-temperature cooking. Amino acids in proteins and carbonyl groups in sugars react to form AGEs. This process is called the Maillard reaction. Three dozen different AGEs have been identified, and some of them contribute to the aroma and flavor of cooked food.

Some AGEs that are frequently found in food include:

• N?-carboxymethyl-lysine (CML)
• N?-carboxyethyl-lysine (CEL)
• Pyrraline
• Crossline
• Pentosidine
• Imidazolium cross-link derived from glyoxal and lysine-lysine (GOLD)
• Imidazolium cross-link derived from methylglyoxal and lysine-lysine (MOLD)

Some AGEs are also formed in your body by your metabolism, and tobacco use is yet another source of AGEs. 

These molecules collect over time, and cause oxidative stress to your cells and tissues.

AGE production in the body increases with age.

AGEs are present in the body at all times. At low levels, they don't cause significant injury. However, they cause cell and tissue damage when they reach high concentrations. They bind to cell receptors and cause oxidative stress and inflammation.

The collection of AGEs in cells affects their structure and function. The cells of the blood vessels are among those affected by the action of these molecules. AGEs also activate monocytes: white blood cells that can increase inflammation. AGEs block nitric acid activity and generate reactive oxygen species that harm the tissues. These compounds can impact the function of proteins within the cells, alter the behavior of hormones, cytokines, and free radicals, and modify the extracellular matrix between cells.

AGEs activate inflammatory and other destructive processes in many systems of your body. Hyperglycemia (high blood levels of glucose) is one condition associated with more AGE production, causing blood vessel damage in people with diabetes. People with diabetes are also at greater risk. 

High levels of circulating AGEs are also linked to:

• Diabetes
• Chronic kidney disease
• Metabolic syndrome
• Memory loss
• Alzheimer's disease
• Anemia
• Polycystic ovary syndrome
• Erectile dysfunction
• Bone health disorders
• Periodontitis
• Nerve damage (peripheral neuropathy)
• Schizophrenia

Dietary AGEs are the largest contributors to the build-up of these compounds in your body. Reducing their intake, therefore, lowers markers of inflammation and oxidative stress in healthy people, as well as those with kidney disease and diabetes. Lessening the consumption of dietary AGEs even delays aging and reduces the risk of chronic disease.

Some foods are particularly high in dietary AGEs — beef, cheeses, pork, fish, eggs, and poultry. Lean meat and poultry also contain large amounts of these compounds when cooked with dry heat. Lamb, on the other hand, has low amounts of dietary AGEs.

Cheeses contain AGEs even though they're made without heating. Full-fat American and Parmesan cheeses contain large amounts of AGEs compared to low-fat cheeses such as cottage cheese, reduced-fat mozzarella, and 2% milk cheddar. Other foods that contain AGEs despite not being cooked include butter, cream cheese, mayonnaise, and margarine.

Carbohydrate foods are generally low in AGEs. Most carbohydrate foods are rich in vitamins and antioxidants, which perhaps oppose the formation of these harmful compounds. However, heat-processed foods like chips, cookies, and crackers have larger amounts of AGEs.

Bread, grains, legumes, milk, and fruits contain very small amounts of these compounds. Low-fat milk is even safer than the full-fat variety. On the other hand, even grain products can be high in AGEs if they are cooked with added fats. Biscuits, though, are higher in AGEs than bagels, low-fat breads, and rolls.

Cooking methods have an enormous effect on AGE production. Cooking eggs in an open pan over low or medium heat generates only half the AGEs produced when cooking over high heat. Poaching or steaming generates only one-fourth of the AGEs of roasting or broiling. 

In general, lower moisture levels and higher temperatures during cooking produce more AGEs. Microwaving, though, produces less AGEs than other dry heat cooking methods, and marinating meat in an acidic solution (like vinegar or lemon juice) before cooking also reduces AGE production.

AGEs build up in your body and damage many types of cells and tissues. To keep yourself safe:

Cook wisely

Use low-temperature methods of cooking. Moist heat like boiling, steaming, poaching, and stewing will generate fewer AGE molecules than dry methods and high-temperature methods like roasting, toasting, and broiling.

Food choices

Plant-based foods, in general, have lower amounts of AGEs than animal products. Low-fat dairy products are safer than full-fat options.

Physical activity

AGEs are more likely to build up in your body if you lead a sedentary lifestyle. Increase your physical activity to reduce the circulating levels of these dangerous substances.

Medicines

Treatments are being developed to oppose the action of AGEs in the body. Two of them, aminoguanidine and ALT-946, are known to reduce AGE effects. Aminoguanidine has also been shown to slow the progress of kidney disease in people with diabetes. 

Pyridoxamine, the natural form of vitamin B6, also opposes the action of AGEs.

In summary, AGEs from the diet can accumulate in the body, leading to chronic diseases. The use of high-protein diets in particular may expose you to more of these dangerous molecules. Still, you can lessen AGE health dangers by regulating your food and cooking choices and leading an active lifestyle.