Friday, August 22, 2008

You better eat your . . . Frosted Flakes?

The food puritans are critical but you will note the total lack of any double-blind evidence that there is anything wrong with Frosted Flakes. Given the way in which double-blind studies overturn conventional wisdom, I would not be surprised if Frosted Flakes are in fact good for you. It appears to be their sugar content that is drawing objections but if sugar is bad for you we should all be dead

Olympic legend Michael Phelps will appear on boxes of the Kellogg's brand sugar cereal, drawing sharp criticism from health experts worried about the message he'll be sending to children across America. "I would not consider Frosted Flakes the food of an Olympian," said nutritionist Rebecca Solomon of Mount Sinai Medical Center. "I would rather see him promoting Fiber One. I would rather see him promoting oatmeal. I would even rather see him promoting Cheerios."

The announcement yesterday that Phelps, 23, winner of a record eight gold medals at the Beijing Olympics, would grace Frosted Flakes and Corn Flakes boxes instead of the traditional athlete's choice of Wheaties left many perplexed. Frosted Flakes has three times the amount of sugar as Wheaties and 1/3rd the fiber.

This doesn't matter much to a virtuoso swimmer who consumes 12,000 calories a day. Still, in a country where childhood obesity is an alarming issue, Phelps' iconic image sharing space with Tony the Tiger sends the wrong message, experts say. "For a guy like Michael Phelps who isn't worried about obesity because he's burning thousands of calories as an athlete...eating Corn Flakes and Frosted Flakes every so often is not an issue," Solomon said.

The Phelps-emblazoned cereal boxes hit supermarket shelves in mid-September.


Taking your tablets with fruit juice limits the effect

Anyone taking medication should beware of drinking fruit juice, Canadian researchers have found. Grapefruit, orange and apple juice can all have a significant effect on the uptake of drugs - either lowering or increasing their effectiveness. While the influence of grapefruit juice is already well known, and some drug labels caution against drinking it with medicines, the latest research has extended the need for care.

Results presented to the American Chemical Society meeting in Philadelphia yesterday by David Bailey, Professor of Physiology, Pharmacology and Medicine at the University of Western Ontario, show that fruit juices can limit the effects of several drugs, including three beta-blockers used to treat high blood pressure, the cancer drug etoposide and some antibiotics.

In tests, healthy volunteers took fexofenadine, an antihistamine. They swallowed the drug with either grapefruit juice, water containing naringin - the chemical that causes the fruit's bitter taste - or plain water. When the medicine was taken with grapefruit juice, only half as much of the drug was absorbed into the body as it was with water.

Naringin and similar substances in orange and apple juices appeared to block a "transporter" molecule called OATP1A2 which helped to shuttle drugs from the small intestine to the bloodstream.

Drugs whose levels in the body were boosted by grapefruit juice were affected by a different mechanism that prevented them being broken down. Professor Bailey originally discovered the drug-boosting effects of grapefruit 20 years ago. He said: "I'm sure we'll find more drugs that are affected in this way." Most medicines should be taken only with water, he said.


Breakthrough could end reliance on blood donations

HUMAN blood has been grown in the laboratory for the first time in research that promises an almost limitless transfusion supply. The achievement by scientists in the US could lead to trials of the blood within two years, and ultimately to an alternative to donations that would transform medicine.

If such blood was made from stem cells of the O-negative blood type, which is compatible with every blood group but is often in short supply, it could be given safely to anybody who needs a transfusion. Stem-cell-derived blood would also eliminate the risk of transmitting the pathogens that cause hepatitis, HIV and Creutzfeldt-Jakob disease through transfusions.

Scientists behind the advance said that it has huge therapeutic potential and could easily become the first application of embryonic stem-cell research to enter widespread clinical use. "Limitations in the supply of blood can have potentially life-threatening consequences for patients with massive blood loss," said Robert Lanza, of Advanced Cell Technology in Massachusetts, who led the experiments.

"Embryonic stem cells represent a new source of cells that can be propagated and expanded indefinitely, providing a potentially inexhaustible source of red blood cells for human therapy. The identification of a stem cell line with Onegative blood type would permit the production of compatible 'universal donor' blood."

Blood comes in four groups, A, B, AB and O, and in two rhesus types, positive and negative, and only some of these are compatible with one another. A person with type A, for example, can donate to people with type A or AB, and receive blood of type A or O. Only O-negative blood can be given to any patient. While there is no national shortage of donated blood in Britain, O-negative blood sometimes runs low. It is also used widely in military medicine.

The research also has more immediate clinical promise for efforts to turn embryonic stem cells into other types of tissue, to treat conditions such as diabetes and Parkinson's. One of the biggest safety hurdles that must be cleared before stem-cell therapies enter clinical trials is the risk of uncontrolled cell growth causing cancer. Red blood cells, however, do not have nuclei that carry the genetic material that goes wrong in cancer, and thus should not present this danger. "This could be one of the biggest breaks for the early clinical application of embryonic stem cells," Dr Lanza said. "There is still work to be done, but we could certainly be studying these cells clinically within the next year or two."

While a few red blood cells have been created from embryonic stem cells before, the ACT team is the first to mass-produce them on the scale required for medical use. They also showed that the red cells were capable of carrying oxygen, and that they responded to biological cues in similar fashion to the real thing. About two thirds had no nucleus, which suggests that they are fully fledged adult red blood cells, and the researchers hope to bring this closer to 100 per cent. Details of the research are published in the journal Blood.

Though embryonic stem cells were used in this experiment, it may be possible to create blood from reprogrammed adult cells, also known as induced pluripotent (IPS) cells. These would circumvent some ethical objections to the use of embryonic tissue.

Independent scientists welcomed the work. Professor Alex Medvinsky, a blood stem cell expert at the University of Edinburgh, said: "The problem with relying on donated blood is that there are always shortages. The ability to generate red blood cells in very large numbers would be a very big thing."


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