
The main function of insulin is to drive glucose from the bloodstream into cells.
But when we eat a Western diet, the cells tend to become resistant to the effects of insulin.
When this happens, the pancreas start secreting even more insulin to remove the glucose from the bloodstream, because elevated blood glucose is toxic.
This is how insulin resistance leads to elevated insulin levels in the blood.
But insulin also has another important function… it tells the fat cells to pick up fat from the bloodstream and to hold on to the fat that they already carry.
This is how insulin causes obesity.
When the body becomes even more resistant to insulin, the beta cells in the pancreas eventually become damaged and lose the ability to produce sufficient insulin. This is how you get type II diabetes, which now afflicts about 300 million people worldwide.
Excess fructose is a known cause of insulin resistance and elevated insulin in the blood (8, 9, 10).
Bottom Line: Excess fructose consumption can lead to insulin resistance, a stepping stone towards obesity and diabetes.
Excess sugar consumption has been associated with many Western diseases.
If anything, sugar is the single largest contributing factor to the poor health of affluent nations.
Every time sugar (and refined flour and vegetable oils) enter a population’s diet, these people become sick.
Sugar has been associated with:
Obesity. Sugar causes weight gain via various mechanisms, including elevated insulin and leptin resistance (11, 12).
Diabetes. Sugar is probably a leading cause of diabetes (13, 14, 15).
Heart disease. Sugar raises the bad cholesterol, triglycerides and causes various other issues that can ultimately lead to heart disease (16, 17).
Bottom Line: Excess sugar consumption has been associated with many serious diseases, including obesity, type II diabetes and cardiovascular disease.
n area in the brain called the Hypothalamus is supposed to regulate our food intake.
In a study published in 2013, two groups drank either a glucose-sweetened drink or a fructose-sweetened drink (18).
The glucose drinkers had decreased blood flow in the hypothalamus and felt satiated, while the fructose drinkers had increased blood flow in this area of the brain.
The fructose drinkers felt less satisfied and were still hungry.
Another study revealed that fructose didn’t reduce levels of the hunger hormone ghrelin like glucose. The more ghrelin, the hungrier you are (19).
Bottom Line: Studies comparing fructose and glucose show that fructose does not induce satiety like glucose, which will contribute to a higher calorie intake.
When we eat sugar, dopamine is released in the brain, giving us a feeling of pleasure.
This is actually how drugs of abuse like cocaine function (20).
Our brain is hardwired to seek out activities that release dopamine. Activities that release an enormous amount of it are especially desirable.
In certain individuals with a certain predisposition to addiction, this causes reward-seeking behavior typical of addiction to abusive drugs.
Studies in rats demonstrate that they can in fact become physically addicted to sugar (21).
This is harder to prove in humans, but many people consume sugar and other junk foods in a pattern that is typical for addictive, abusive compounds.
Bottom Line: Sugar, due to its powerful effects on the reward system in the brain, can lead to classic signs of addiction.
Leptin is a hormone that is secreted by our fat cells. The more fat we have, the more leptin is secreted.
This is supposed to function as a signal to tell the brain that we’re full and need to stop eating. It is also supposed to raise our energy expenditure.
Obese individuals actually have high levels of leptin, but the problem is that the leptin isn’t working.
This is called leptin resistance and is a major reason why people eat more calories than they burn and become obese.
Fructose is a known cause of leptin resistance, both because insulin blocks leptin signalling in the brain and because fructose raises blood triglycerides which also blocks the effects of leptin (22, 23, 24).
This makes our brain think that the fat cells are empty and that it needs to keep eating.
Willpower is very weak compared to the leptin-driven starvation signal.
This is the reason people can’t just “eat less, move more” and live happily ever after.
To reverse leptin resistance and make the brain WANT to eat less, sugar has to go.
This article was republished with permission from Authority Nutrition.
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Moderation. Fructose is fine in moderation and when consumed by a person with self-control.
Fructose isn't the root cause of chronic western disease, lack of self-control is.
Hmm. Makes me glad I don't drink sodas. They say that's a big 'un when it comes to sugar intake.
---
Always defer to facts rather than philosophy.
Process sugar = evil.
Other sugars keep to a minimum.
Overall in your daily routine, you want blood sugars to not dip up or down, but maintain a contant normal level, in my opinion. ;)
@Bagpipes100:
www.cnn.com/2013/03/13/opinion/gostin-soda-ban/index.html
I'm gonna argue that lack of self-control isn't even the root cause. It's our own psychology. Willpower is a limited thing for everybody, and if bigger portion sizes mean we subconsciously eat more && we're constantly surrounded by them, the average person is going to give in regularly.
Yeah but Mary Poppins says a spoon full of sugar helps the medicine go down. So who ya gonna believe? Somebody that spells Chris with a K or a lovable nanny who can sing, dance and fly with an umbrella?
cussnu,
You funny!
@J. James: What you've been told is absolutely correct. 5dl of soda typically contains ~40 grams of sugar (sorry for the metric units, they are the only ones I know).
As a Type-I diabetic, I occasionally get into state called hypoglykemia, i.e. the glucose level in my blood goes dangerously low (because I've eaten too little and injected too much insulin or excercised too hard), the standard cure is to swipe down a 5dl bottle of soda. Doesn't much matter what it is, as long as its not a sugar free diet soda.
In about ten minutes I'm OK, and ready to again. Problem is, if I had two sodas, instead of just one, my bloodsugar would skyrocket to dangerously high levels instead (Hyperglykemia. More insulin, and here we go again)...
I think this is quite telling. Sodas have a lot of sugar in proportion to their nutritional value (which is exactly none).
Nowadays, when I occasionally go grab a hamburger with my kids, we just take the hamburgers, share one or two packets of fries and drink milk instead of soda or juice. Much better, and much healthier. Try it. It's quite OK, and you will feel more sated after the meal. And I do mean, really.
The point is, if you can avoid sugared sodas, do so. If you do, you can afford an occasional candy bar or some french fries. But if you don't, and do soda, candy bars, french fries and everything else you "like" (Do you really? Ask that question...), you will definitely run the risk of getting Type-II diabetes, and that is a serious bitch of a disease, that you really, really do not want to catch. It's not as bad as metabolic syndrome, but still requires a total change in lifestyle and diet unless you want all the related "bad stuff" to happen. Which you do not.
This is actually one, quite small move to stay in shape. Eat more fruit and vegetables, and enjoy refined sugars only occasionally. And when you do, enjoy the experience, instead of concentrating on the television, computer, tablet or some other diversion...
Wish juice made from fruit and vegetables was noted. I assumed that my Jack La Lane was making good stuff. Could it be that this sweet juice is just as bad and pure corn syrup?
jefro,
We all die as in Jack La Lane, drinking his juice or not, the question is at what qualities of life do we enjoy and live, prior to our death?
@jefro: I'm not an nutritionist (I'm a bad ass multi-disciplinary industrial IS/IT systems designer instead), but my bet is that fruit and vegetable juices are better for you than your standard soda because they mostly lack refined sugars and usually contain actual nutrients.
That said, I know exactly what a professional nutritionist would say, and that is that avoid the juices and eat the fruit and vegetables and stick to water to quench your thirst.
I agree/disagree on this. If you have glass or two a day of your juice, there's no problem. If you drink the whole canister, then there might be... Juices tend to have a higher concentration of sugars than the fruits or vegetables they've been made of, regardless of the brand.
From a diabetic point of view, this is the essential basic problem. If you want to stay good, you must limit your daily intake of sugars, be they refined or not.
And 10 years from now, protein will be the dietary boogieman.
Honey is the same thing as HFCS. Are you saying honey is sugar's evil twin?
Fruit is chock full of fructose. There are vegans who eat fruit all day long (fruitarians) and are very likely much healthier than the average bear.
Processed foods are the problem, not one single macronutrient.
@ppardee: Well, yes honey is mostly the same stuff that HFCS is. So tell me, how much honey do you eat a day? 20 grams, as a heavy user? I like honey a lot, but my use of it is around 50 grams - a month.
That's nothing compared to the 160-200 gram intake A DAY you get of HFCS you get from inbibing a moderate 2 liters of soda daily.
As I told, I have Type-I diabetes, and once I actually had to eat 2 dl honey (Italian forest honey) with a tablespoon. I was about to gag by the sixth spoon. You really can get too much of the good thing.
Fruit has fructose. Of course. But it also tends to have a lot fibers, and fibers inhibit the release of the sugars in your body. The process is thus much slower than taking the fructose in a pure firm. Besides, we are speaking about concentrations here. One glass of OJ contains the juice of 5-10 oranges. When did you eat even 5 oranges in a row. Never?
But why do I care? Believe your own BS, get sick, get all your limbs cut off, get blind, and die a painful death in disgrace and dementia. Go ahead. I hope you have someone who loves and looks after you.
Believe me, I've seen these cases in reality, and this is the reality and not a figment of a sick mind. Worst thing is, once the reality hits, it's usually too late, and the limb cutting begins.
I am not sh*tting you. This is real.
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This may cause this not to be printed or to be removed, but, again, note the role of misinterpretation and misrepresentation.
Among other things, note the carefully imprecise use of the term “sugar”. In fact, “sugar” seems to be being applied everywhere, for every for of “sweetener”, likely to artificially endow less beneficial substances in the public's mind with the qualities of real sugar. Sugar, generally thought of in the same context as table sugar is more than 99% sucrose. There is almost no fructose in it at all. Table sugar is perfectly safe and free from the dangers listed here. Especially since, equally imprecisely, the article is invoking the word “sugar” and equating it absolutely with fructose, then leaving it to the “rubes” to con themselves into thinking that what's being said is true of all sweet substances. In fact, when the article imprecisely refers at the beginning to “added sugar”, it does not, remember, not, refer to table sugar. The article is imprecisely and misrepresentingly, referring to “industrial sweetener”! Yet it is content with leaving the average reader thinking that the sugar seen in shakers, granular sugar, necessarily is half fructose! It is not and should not be thought of that way! The degree of misrepresentation in many areas of the dispute over sugar is genuinely reprehensible and is something the average consumer should be aware of. Since, apparently, even such a venue as Popular Science cannot be relied on to be wholly reliable in its representation on the matter!
julian,
Table sugar IS half fructose. Sucrose is a disaccharide, meaning that it consists of two monomers of sugar linked together. In sucrose, these two molecules are a fructose and a glucose. Other dissacharides have other combinations. Maltose, for example, is two glucoses. The body quickly cleaves dissacharides into its constituents, so solid sucrose is effectively the same as a fructose/glucose syrup, AKA corn syrup/the industrial sweetener you mention, to the body.
For the record, I wholeheartedly agree with quintus; its the fact that we consume overly condensed nutritive sources, such as OJ, that mainly lack fiber thats making Americans fat. Soda isn't the problem: its all condensed sources of nutrition, and juices, even organic juices are hardly better than soda for this reason. People love to spout that juices have "micronutrients" and "enzymes" and all that, but in reality we arent deficient in micronutrients in this country; what we're deficient in is bulking agents, such as fiber (and even gelatin AKA gristle) that are systematically removed from food products to make them taste sweeter, saltier, meatier, easier to eat etc but also less filling so you'll eat (and buy) more.
@juilianpernod: Your input was and is pure and utter "paskaa". BS, in my mother tongue.
"Hon, could you give me the tablesugar, my beef is not sweet enough"?
WTF? "Tablesugar"? What's that? C'mon... Hopeless.
Eat veggies, fruits, grains and think of meat as a spice(eat small), you'll be fine!
The game of real life ...
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@ Anylcon, studies have been inconclusive, and generally show that raw sugar is pretty much the same as processed, notably, high fructose corn syrup (just google high fructose corn syrup vs. sugar, and you'll get tons of articles and studies). They're both equally bad for you. Don't fool yourself that you're doing your body a favor by going with sugar over HFCS. Conversely, don't feel too guilty about going for a treat that contains HFCS (but try and make sure it's a treat and not a staple of your diet).
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sombieninja, you contradict yourself. Your scenario is ENTIRELY centered around self-control. Shifting blame is disingenuous.
dave1976,
Who are you arguing with?
Here we go again.........more scare tactics to try to control what is good for you and what's not good for you.
Wasn't it awhile back that the AMA was saying how bad coffee was so bad for you? Now all of a sudden it's one of the healthiest beverages to drink.
Enjoy life and baaa humbug to all these control freaks out there!!
@Quintus: You think 2 liters of soda a day is moderate? The problem isn't HFCS. You can be paranoid about it if it makes you feel powerful. It doesn't hurt anyone but you.
My point was that it isn't a single thing that is the problem. It isn't fructose, trans-fats, carbs, fat or dietary cholesterol. It is the fact 75% of everything the average person eats is processed beyond recognition.
Kids wake up, eat a poptart or bowl of fruit loops with reduced-fat, pasteurized, homogenized milk, then have a sandwich made with processed cheese and processed ham on white bread and a bag of potato chips for lunch, then grab fruit-shaped gummies as a snack, then come home and have hamburger helper for dinner.
The enemy is processed foods. HFCS is present in a lot of processed foods Blaming HFCS is like blaming the bear's claw for the mauling when it's the bear that needs to be avoided.
More and more food producers are switching from high fructose corn syrup to sugar in their products. That's an important step forward and needs to be supported.
@ppardee: You are right, of course, and I do agree with you in everything you say.
However, the reason I point my finger at sodas sweetened with HFCS (or sucrose, it really doesn't matter that much in the end...), is that people usually drink beverages to quench their thirst and not to still their hunger.
As such, many individuals don't even think about the amount sugars in an innocent bottle of soda, as it is not "food". And as people tend to be thirsty much more often than they are hungry, sodas form particularly dangerous and sneaky vector to introduce unneeded sugars into the metabolism.
In addition to all the sugars in processed foods, this causes a very heavy, and unnecessary load on the metabolism, which can cause serious problems later on.
The essential problem is maybe that many people can't afford to buy fresh produce, and also that many who can, don't have the time and/or the skill to make a meal out of it. This is a bit sad, I think. Well prepared food is such an enjoyment, that it should be declared a human right in itself.
I think that it also might be in order to point out that I am not one of those "low-carb" crazies. I eat carbs, and would eat much more if I could. Love them, in fact. Pasta is my favorite, but as a diabetic, I must be careful. But so should healthy people also be.
This is a great video that explains Sugar and Fructose really well.. I have watched it 2x and have recommended it to all my friends...
Sugar: The Bitter Truth by UCtelevision • 3 years ago • 3,312,270 views
http://www.youtube.com/watch?v=dBnniua6-oM
It was hard reading while drinking a can of Starbucks Coffee flavored doubleshot energy drink.
Quintas...even if you only know metric units...who the hell refers to the size of sodas in DECILITERS?
Also Quintus...You can whine and say "get all your limbs cut off" well...sorry that your lifestyle was such that you got diabetes. I can handle my sugar from soda because I actually GET OUT OF THE HOUSE once in awhile! I don't drink 2 liters ofsoda a day...VERY few people do. But I drink 2-3 cans a day so about 1 liter. And yet at age 41, my body fat percentage is under 10%. Well trained athlete levels. So go ahead and ignorantly blame a food rather than a lifestyle if you want. But realize it only makes you look stupid.
Show me a scientific study that shows that, in general, people who eat less sugar live longer.
Oh wait, there is no such study.
Did you know there has also never been a scientific study that showed that thin people live longer, or even that people who EXERCISE live longer?
Look it up. It's genetics, people. All else is foolery.
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Wttp/jaec45: I love sugar. It feeds my brain. My CSF is so sweet.