Right, soy isolate is different. Also, whey isolate is made very differently from whey concentrate. Whey concentrate is the subject of the papers above noting furosine content, so we’ve been talking more about whey isolate and how it’s made (liquid whey is typically spray-dried with a little heat to make the powder.)
I have yet to find material implicating any protein powders as containing high amounts of AGEs, or specifying amounts of AGEs in different kinds of protein powders. There are many lists of AGEs in foods, especially those foods high in AGEs, but am not finding the same for protein powders.
There is also considerable debate about just how much dietary AGEs matter. We know that the body forms AGEs irrespective of consumption; AGEs are produced/present in many disease conditions. In addition, we can consume AGEs in foods, and some of those make it into our system.
Using the old, “where there’s smoke, there’s fire” metaphor… One approach says that AGEs produced in the body are like smoke produced by fire, and are a sign of a problem, but the fire is the real problem… while AGE’s consumed in food are just eating some smoke, which does not point to a fire. If there’s no fire, it’s not as bad, but the question remains how much smoke one can take before it’s a problem.
Another approach says that dietary AGEs are pro-imflammatory, so eating a lot of them over time is a bad thing, but in a completely different way than the body’s internal fires that produce AGEs.
The last approach - which is basically, “AGEs are bad in the body so AGEs are bad to eat so avoid all AGEs” is too simplistic for me, and is usually voiced loudest by someone selling something.
There is some interesting research that suggest dietary AGEs are not associated with the same problems as endogenous (bodily-produced) AGEs. Again, it’s possible that endogenous AGEs are not so much the cause of cancers, but rather a symptom of something else that is related to causing cancer. Conversely, dietary AGEs do seem to be associated with things like colon cancer - eating a large amount of something that’s pro-imflammatory which gets through most of your digestive system to your colon and then sits there is liable to help promote cancer, so that makes sense.
It’s a complicated matter to resolve.
Here’s a study that implies dietary AGEs do not relate to internal cancers:
Ann N Y Acad Sci. 2005 Jun;1043:467-73.
Are food advanced glycation end products toxic in biological systems?
Chuyen NV, Arai H, Nakanishi T, Utsunomiya N.
Japan Women’s University, Department of Food and Nutrition, 2-8-1 Mejiro-dai, Bunkyo-ku, Tokyo 8681, Japan. firstname.lastname@example.org
Model food advanced glycation end products (AGEs) were prepared as glycated casein (GC) and glycated soy protein (GS) by the reaction of casein or soy protein with glucose at 50 degrees C, relative humidity 75% for seven days in a powder state. These browned proteins were used as materials for animal experiments. A mixture of 20% glycated proteins (GC:GS = 1:1) diet was fed to streptozotocin (STZ)-diabetic rats for 11 weeks. The results showed that: (1) fructoselysine was observed in the hepatic portal veins, arteries, and femoral veins of rats fed with glycated proteins after 2 h of feeding; (2) blood sugar of glycated protein-fed rats was lower than that of diabetic rats fed with intact protein, while HbA1C in blood and glucose in urine of both groups were similar; (3) lipid peroxidation status in serum, liver, and kidney of both groups was similar; (4) superoxide dismutase (SOD) and glutathione-S-transferase (GST) enzymatic activity in serum and liver of both groups were also similar; (5) there were no differences in degree of cataract formation and concentration of glucose, fructose, sorbitol, and lipid peroxide in the lenses of both groups. From the above results, it can be estimated that food AGEs are not toxic in biological systems, and reactive oxygen species increase in diabetic rats is not caused by glycated proteins but by other pathways.