Interesting comment on glucose

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"Glucose in the blood is toxic? If glucose is toxic then why does the glycolysis exist? Why does the human body have 10 specific enzymes specifically evolutionary adapted to break down glucose? Why does the human body have another additional 8 specific enzymes to convert glucose to ATP in the Citric Acid Cycle? If glucose is so toxic for us then why is the human body mainly adapted to convert glucose into energy? This is stuff we learn at elementry chemistry in 12th grade. I have students that are 16 years old that are supposed to know this in order to pass high school. There is so much misinformation and misunderstanding in your reasoning behind glucose and how ATP production works. Glucose is NOT toxic. Glucose is even stored in the body as energy in your muscle cells as glycogen. This is ridiculous. Why do you even call yourself a "nutritionist" when your basic understanding of human cellular biology is less than that of a high school student. Because anyone can call themselves a "nutritionist". It's an unregulated title that anyone can have and that is in itself meaningless. This is pathetic to say the least." - YT comment on a high fat promoters video.
 

EIRE24

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Yep. That's what I've always thought. Don't understand why high carb doesn't work for some people though? That's what contradicts what he says.
 
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Westside PUFAs
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EIRE24 said:
post 110551 Yep. That's what I've always thought. Don't understand why high carb doesn't work for some people though? That's what contradicts what he says.

It could be that people have different enzymes or lack of certain enzymes that cause different reactions such as when some obese people do not have a problem metabolizing glucose or no type 2 diabetes. It seems like they may have some enzyme action that is unique. But you should be clear on what your definition of "high carb" is because many people claim to eat "high carb" but in reality they eat high fat and protein. I'm not saying that high fat or high protein is bad or good, I'm just saying that people don't always count their macronutrients properly. Carbs come in 3 main forms:

1. Starch, which has 3 sources:

1. Most tuber "organs" or "storage organs": potato, yam, sweet potato, parsnip, celeriac, burdock, tapioca, sunchoke, jicama, rutabaga, water chestnut, taro, cassava and many others that are available around the world. Some tubers have more simple sugar than starch such as beets and turnips.
2. Grains - rice, amaranth, barley, buckwheat, farro, emmer, kamut, millet, muesli, quinoa, rye, sorghums, spelt, teff, triticale and many others.
3. Above ground storage organs, winter squashes - butternut, acorn, Hubbard, banana, pumpkin, buttercup, turban. Summer squash are usually low in calories which makes sense, summer = fruit, winter = steamed starch to keep warm and be the carbohydrate source when fruit is not there, in the non-tropics.

2. Fruit, which can be in whole fiber form or the extracted juice. The effects of eating whole fruit or just consuming the juice will cause different reactions for people. Some fruit provides lots of juice while other provide very little juice such as dragonfruit.

3. Extracted sweeteners like sugarcane, maple syrup, and honey. There foodstuffs provide glucose and other sugars but lack micronutrients therefore should not serve as the base of ones carbohydrate source. But they can be used in context or therapeutically.

Legumes, lentils, peas, and some other foodstuffs have starch but they also have a high amount of protein so to call them a carbohydrate is a misnomer. All other plant foods have some amount of carbohydrate such as "greens" or odd vegetables such as eggplant but the carbohydrate content of them is far too low to consider them carbohydrate sources. Thus, fruits, roots, winter squashes, grains, and sweeteners are the main "natural form" carbohydrate source for humans with lactose being the only animal source. When you picture the starch source or carbohydrate, you must picture them in the form of steamed/baked with no fat or protein added to them, in the context of analyzing them. Once fat and/or protein is added to them your macronutrient ratio changes and this is where many people mistakenly still call themselves "high carb."

Flour products should not be called "carbs" because they are usually cooked in fat such as donuts cooked in oil/butter and many then also have fat or protein added to the flour products such as pasta with meatballs and cheese or pizza.
 
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Suikerbuik

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I've been writing things down lately and I guess it will fit here (left out a few things, hope it's still complete):
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Sugar is currently being blacklisted. Many people, often those who follow paleo-diets, consider sugar as the cause of most modern diseases.

The 3 most often mentioned reasons against sugar are:
1.We've never had this neolithic food during our evolution.
2.Fructose is alcohol without the buzz.
3.Sugars suppress the immune system.

I am no advocate of blindly eating sugar up to all you can eat, or say that added sugar is good. No...sugar has its possible downside and in some contexts it is actually damaging, for example when it is converted into d-lactic acid or stimulates pathogenic flora in the upper gut (causing inflammation and increased permeability). High fructose corn syrup (HFCS) is also something I avoid too, because it can contribute to intestinal inflammation; intestinal inflammation is something you should always try to avoid. However, I still enjoy my carbs instead of seeing them as toxins.

The first reason is obscure. I think it probably mostly us romanticizing our past. The tropics provide an abundance of fruits, and no they are not sour. Also, Weston Price has written about healthy tribes consuming grains, starches and fruits, and even more recent Jeff Leach from the human food project notes: “despite the fact that Hadza consume >50-75% of their calories from honey for certain months in the wet season, and eat almost nothing but berries on end during other periods, and lots of meat during dry season, and so on – their BMI remains more or less constant (~20 for men and women – note Marlowe’s group has estimated body fat for men ~11% and women ~20%).”. There are even studies suggesting that starch consumption is what led to the increase in brain size, ignited by fat consumption.

The second reason is partly true. Research does point towards fructose stimulating triglyceride and cholesterol synthesis, especially in a hypercaloric glycogen-replete state overwhelming the mitochondrial capacity. However, stating that dietary fructose is the main cause of fatty liver diseaseor metabolic syndrome, is a bridge too far. Namely, the state the liver is in is very important in determining its processes and mitochondrial function; informed by cortisol, estrogen, endotoxins, adrenaline, pufa, insulin etc. Also, mice given antibiotics did not show such profound lipid accumulation, indicating that endotoxin stimulates hepatic steatosis.
However, fructose in excess does deplete cells of ATP inducing a loss of intestinal integrity, and alike glucose and numerous food additives, increasing paracellular transport possibly enhancing endotoxin influx. So there could be a role for fructose and sugars when used in excess, but that is not what these studies have shown, i.e. in humans consmuning a balanced diet consisting of proteins, fats and carbs altogether.

The supressed immunity has possibly to do with the aforementioned reason. The anti-sugar cult often cites a study from 1973 in whereas subjects were given 100g glucose, fructose, sucrose (half glucose, half fructose), honey, orange juice or starch. Blood samples were taken before and at different time points after ingestion – up to 5h. Neutrophils were extracted and incubated with Staphylococcus Epidermidis after which the engulfed bacteria were counted. The results show that after a dose of a particular sugar, but not starch, there is a significant reduction in engulfed bacteria, assuming sugar suppresses our immunity. I find a dose of 100gm of a sugar not really representative to be honest. The study itself outlines that theyre presently, in 1973, studying the effects of various carbohydrates as well as a possible role of protein, fat and ordinary meals on neutrophilic phagocytosis. (Un)fortunately I couldnt find any interesting with respect to the claims that sugar suppresses immunity, besides other research showing that increased glycolytic activity, ROS formation, the glycosylation reactions and few else, affect neutrophils negatively (logic of course). I am inclined to believe that a balanced meal with carbohydrates and supportive nutrients does not produce this immune suppressive effect. This may even be suggested from their experiment itself. Because starch, often even fairly insulinogenic, doesnt profoundly affect phagocytosis - initially phagocytosis even increased. Substantiated by previous mentioned research indicating that sugars, fructose in particular, can lead to abnormal distribution of tight junction proteins and increased paracellular permeability, I think the 100gm of pure sugar is too high and activating those neutrophils on beforehand. So instead of those being suppressed, they could be fixing the damage that a sudden high dose of simple sugars is capable of inflicting.

In this respect it makes sense to me, because our immunity is indeed weakening these days; there's no way to get around that. But for this reason I avoid substances like carrageenan (polysaccharide from seaweed), polyunsaturated fatty acids and supplement additives, to name a few. I have yet to see evidence for this to be caused by supposedly Neolithic carbohydrates in a natural balanced diet (e.g. accompanied by fats and proteins).

Another reason you are sometimes told why to avoid sugar, is that sugar glycates proteins. But so do polyunsaturated fatty acids, forming advanced lipid oxidation end products, even happening much quicker. Noteworthy also, the glycation of proteins by glucose is largely inhibited by carbon dioxide.

Considering the issue from a biological/physiological perspective, the paleo, no starch, no sugar angle, makes even less sense. The way we interpret the taste of sugar and the feedback from our reward system, the abundance in breast milk, the synthesis of glycogen, the function insulin, the influence on cortisol and adrenaline excretion, the influence on thyroid hormone metabolism, the warmth it produces in comparison to low carb, the purpose of fruits or roots/tubers seeding new life, and more. All this should provide firm reasoning to not go low carb for a long period of time. See also the quote from Jeff Leach in case you're forgotten; by which I am not saying that you should ingest 100g of fructose crystals or eat 1200 calories from honey, but I mean to say that you should just enjoy your fruits, deserts and coffee with sugar and cream. We and tribes supposedly free of diseases can handle fructose and other sugars just fine in a balanced diet, but possibly more important balanced environment.

So to conclude. When sugar oxidation can become a problem, and it does during times of chronic stress or sickness and aging, we should be careful and watch our feeling. However, we arent likely to help ourselves by going low carb; in fact, a Paleo-diet possibly ruined the life of many and is not sustainable. Since there is no consensus yet, I like Ray Peat's words: Perceive, think, act. If people are still convinced that sugars and starches are harmful Neolithic foods, don't be blinded to the effects of high fat diets can possibly have. Sure, those PUFA rich diet-studies are likely flawed too, and I haven't read them carefully as my experience isn't in favor of them. Nevertheless, the studies I have seen still suggest that high fat diets can stimulate serotonin synthesis, alter gut flora, change circadian ryhtm, cause increase postprandial lipopolysaccharide levels, and more. Exactly my experience and this makes me propose: isolated fatty acids without their natural fibers or nutrients they come along with are to be considered neolithic foods.

Sugars are ubiquitous; they are the light in each food.
 

Parsifal

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Suikerbuik said:
permeability). High fructose corn syrup (HFCS) is also something I avoid too, because it can contribute to intestinal inflammation; intestinal inflammation is something you should always try to avoid. However, I still enjoy my carbs instead of seeing them as toxins.
What's the problem with HFCS?
 

Suikerbuik

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I get intestinal irritation from it, so I avoid it.
 

Parsifal

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Suikerbuik said:
However, fructose in excess does deplete cells of ATP inducing a loss of intestinal integrity, and alike glucose and numerous food additives, increasing paracellular transport possibly enhancing endotoxin influx. So there could be a role for fructose and sugars when used in excess, but that is not what these studies have shown, i.e. in humans consmuning a balanced diet consisting of proteins, fats and carbs altogether.
Your post is really interesting Suikerbuik, thanks.
I found that I tolerate better a diet really high in carbs (maybe 80% of my calories, but lately I'm thinking that it might be too much) and a bit low in saturated fats. Is this an evidence of randle cycle?
When you say that fructose depletes the cell of ATP, why is that? I thought that carbs helped the cell to make ATP converting it to Ribose?
How could fructose make the gut more leaky and not sucrose?[/quote]
 
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Westside PUFAs said:
post 110548Why does the human body have 10 specific enzymes specifically evolutionary adapted to break down glucose? Why does the human body have another additional 8 specific enzymes to convert glucose to ATP in the Citric Acid Cycle?

Because it's toxic :ss that's what they will say and that's what Ray Peat people will say about many enzymes as well...
 
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tara

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Such_Saturation said:
post 110605
Westside PUFAs said:
post 110548Why does the human body have 10 specific enzymes specifically evolutionary adapted to break down glucose? Why does the human body have another additional 8 specific enzymes to convert glucose to ATP in the Citric Acid Cycle?

Because it's toxic :ss that's what they will say and that's what Ray Peat people will say about many enzymes as well...

If it were toxic, how would one explain gluconeogenesis?
 
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