Diabetes, Obesity, Metabolic Disease, Sugars, Aldehydes, and the American Diet [View all]

[ProfessorPlum]

I am a researcher in drug discovery. I have a friend who works on diabetes and metabolic disease drugs, and he has spent a lot of time researching diet, sugars, and their effects on the body. After talking with him, I have a much better understanding of the chemistry of sugars and how they can be harmful. I thought I would share it here in case it helps anyone.

First, some facts about nerves and aldehydes. Aldehydes are quite reactive chemical compounds, and they are particularly toxic in our bodies. They can mark and damage proteins that they come in contact with, and are especially hard on nerves. For example, when people drink wood alcohol (methanol), it is converted to very reactive formaldehyde – which damages nerves, especially optic nerves, which is why drinking methanol often leads to blindness. It pickles the optic nerves. Regular alcohol (ethanol) is first converted to very reactive acetaldehyde in the liver, where it will eventually pickle your liver and do damage to other nerves. With that in mind, let’s look at sugars.

When talking about dietary sugars, we only have to worry about two of them. Fructose and glucose. Sucrose, or table sugar, is immediately converted to a 50:50 mix of glucose and fructose. High fructose corn syrup is essentially the same - it is roughly a 50:50 mix of glucose and fructose (sometimes slightly higher in fructose, like 55:45), but pre-split into its components already, unlike sucrose. High fructose corn syrup has a lot of properties that make it great for manufacturing that sucrose doesn’t, which is why it has been so (over)used in processed foods.

Fructose: The biggest natural sources of fructose are things like honey and ripe fruit. These were wonderful but rare and seasonal finds for our ancestors, and so our bodies convert fructose to fat. This conversion is essentially unregulated in our body. You eat fructose, it gets stored as fat. This is the body’s way of saving serendipitous calories for lean times.

Glucose: this comes from sucrose, corn syrups, and starches. It is _highly_ regulated in the body, which is why we have our complex system with insulin, glycogen storage, etc. that monitors and maintains the level of glucose in the bloodstream. And part of the reason for that is glucose is also an aldehyde. It has two forms, one cyclic and the other linear, and it interconverts between the two forms. In its linear form, it is an aldehyde, less reactive than formaldehyde or acetaldehyde, but it can still damage blood vessels, nerves, proteins, your kidneys, etc. This is why prolonged high levels of glucose in the blood stream damages peripheral nerves, kidneys, eyes, etc. and why diabetes sufferers often have damaged kidneys, eyes, and lose extremities like their feet. Glucose is essentially pickling their nerves and blood vessels, all over their bodies.

So, what does all of that mean for how you should think about food and eating? Here are my recommendations:

1. You want to keep your fructose intake down. This will keep you from getting damaged fatty liver and generally packing on fat everywhere else. This means cut down on sucrose, corn syrup, and other sources of straight fructose like honey and agave nectar. Don’t worry about raw fruit, though. Although it has fructose it comes in a matrix of fiber, vitamins, and other good stuff that both fills you up and provides other nutrients. However, also avoid fruit juices, as they don’t have this matrix.

2. You also want to keep your glucose intake low, so that they level of glucose isn’t so high that you are pickling your delicate insides with it. This means, again, lowering your intake of sucrose and corn syrup, and also all carbohydrates like starches, which are broken down into glucose. Eating more complex starches (whole grains, etc.) slows the entry of glucose into your system (again, it is a matter of having the starch delivered in a complex matrix) compared to simpler starches.

3. Eat lots of fiber and protein to keep yourself full. Lean meats, cheeses, vegetables, fruits, small amounts of nuts, etc. Don’t worry as much about fat, as although it is a source of calories, it also fills you up.

4. Sucrose and high fructose corn syrup are essentially exactly the same as far as your body is concerned. The problem with HFCS is simply that we eat a ton of it. And sucrose, too. Sugars and carbohydrates, in which the American diet is awash, are the culprits for diobesity and metabolic disease. We just eat way too much of them, much more than our nerves, livers, kidneys, and bodies can handle. I know it is really hard, inconvenient, and expensive – but try to cut way down on your carbohydrates, and stick to the more complex starches where you can.

This probably isn’t news to many of you. But if reading this helps even a few people from losing their kidneys or their feet, then it is worth it.