Fructose sugar makes maturing human fat cells fatter, less insulin-sensitive

Jun 21, 2010

Fructose, the sugar widely used as high-fructose corn syrup in soft drinks and processed foods, often gets some of the blame for the widespread rise in obesity. Now a laboratory study has found that when fructose is present as children's fat cells mature, it makes more of these cells mature into fat cells in belly fat and less able to respond to insulin in both belly fat and fat located below the skin.

The results will be presented Sunday at The Endocrine Society's 92nd Annual Meeting in San Diego by lead author Georgina Coade, a PhD student at the University of Bristol in the U.K.

"Our results suggest that high levels of fructose, which may result from eating a diet high in fructose, throughout childhood may lead to an increase in visceral [abdominal] obesity, which is associated with increased cardiometabolic risk," Coade said.

Defined by a large waistline, abdominal obesity raises the risk of heart disease and . The contains one of two major types of fat in the body: visceral fat. The other type, subcutaneous fat, is found below the surface of the skin.

Although researchers have shown the negative effects of fructose on the fat distribution of rodents, the effects of this sugar on human adipocytes, or fat cells, are not clear, according to Coade. Therefore, she and her fellow researchers studied biopsy specimens of both subcutaneous and visceral fat from 32 healthy-weight children who had not yet gone through puberty.

From the biopsy samples, the investigators obtained preadipocytes—the precursors to fat cells that have the potential to differentiate, or mature, into fat-containing adipocytes. They then allowed the to mature for 14 days in culture media containing normal glucose (the main sugar found in the bloodstream and the principal source of energy in the body), or high fructose. The researchers assessed by measuring activity of an enzyme (GPDH) and the abundance of the adipocyte fatty acid binding protein, which are both present only in mature fat cells.

Fructose, the research team found, had different effects to that of glucose and caused the fat cells to differentiate more—that is, to form more mature fat cells—but only in visceral fat.

For both types of fat cells, maturation in fructose decreased the cells' insulin sensitivity, which is the ability to successfully take up glucose from the bloodstream into fat and muscles. Decreased insulin sensitivity is a characteristic of Type 2 diabetes.

Although prolonged exposure to fructose had a negative effect on insulin sensitivity, when Coade and her co-workers exposed mature fat cells, rather than preadipocytes, to fructose for 48 hours, the cells' insulin sensitivity increased. The reason why is unknown. However, she said, "Fructose alters the behavior of human fat cells if it is present as the mature. We can maybe compare this [timing] to periods in children when they are making their fat."

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User comments : 4

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Parsec
Jun 21, 2010
This comment has been removed by a moderator.
TJ_alberta
5 / 5 (1) Jun 22, 2010
doubt it, probably just means that junk food is even worse than previously thought, especially for kids.

Would be interesting if they confirmed their results in vivo, possibly with a few biopsy needles stuck into obese and normal kids.
evolutionarily
4.5 / 5 (2) Jun 22, 2010
Fruit should certainly be moderately consumed, especially much of the franken-fruit that is commonly found these days with sugar content 2-3x higher than found in their non domesticated cousins...

Processed fructose should be totally restricted, as it is not part of our ancestors evolutionary metabolic milieu, particularly due to it being found only seasonally in the wild.^This is essentially the Paleo diet, eating what our hunter gatherer ancestors ate for millions of years, over 99.6% of our evolved history (and 99.99% for many indigenous populations)! Look into it further if this sounds interesting, might just change your life (sure did mine).

Then studies like this all start to transform from random noise into a clearer picture :)
kevinrtrs
1 / 5 (1) Jun 23, 2010
This is normally what happens when human beings refine that which God made into the substances they like.
God created fructose with all its support structures in fruit and human beings have removed those supports when extracting the fructose [ or even synthesizing it].
When the body metabolises fructose from fruit, various factors prevent it from being turned into alcohol. But without those factors the safety belts are off. So it should not be surprising that the pure fructose have bad side-effects.
God knew what the body needed and what it was capable of when He made it. Man does not have all that insight.
Skeptic_Heretic
1 / 5 (1) Jun 23, 2010
This is normally what happens when human beings refine that which God made into the substances they like.
Hilarious.
God knew what the body needed and what it was capable of when He made it. Man does not have all that insight.
Extraordinary claims require extraordinary evidence, present it.

Would you say God knew what the body needed when he built it to fall apart so easily? Since we're his "perfect" creation, is there a reason why he went ahead and created so many things that rather easily overwhelm and kill us?

Can you explain AIDS in your God framework?

Of Course you can't, because it's all silly bullshit.