Fructose Makes Brain Crave High-Calorie Foods, Study Finds; Measles Vaccine Protects Against Other Diseases?

Fructose occurs naturally in honey, fruits, vegetables and their juices — and is found in “high fructose corn syrup” — the much-maligned ingredient added to many packaged foods. Now, a new study finds that fructose could make the brain yearn for high-calorie foods.

Researchers looked at 24 healthy volunteers and noticed that consuming fructose, compared with glucose, resulted in more activity in “brain regions involved in attention and reward processing, and may promote feeding behavior.”

So powerful is the effect of fructose on the brain that it trumps financial rewards, researchers say.

Says the study’s conclusion: “Ingestion of fructose versus glucose also led to greater hunger and desire for food and a greater willingness to give up long-term monetary rewards to obtain immediate high-calorie foods.”

The volunteers drank a 10-ounce glass of cherry-flavored liquid that contained two and a half ounces of fructose or glucose. Researchers also took blood samples to measure levels of glucose, fructose and insulin, and of leptin and ghrelin, enzymes involved in controlling hunger and feelings of fullness.

Before having their drinks, the participants rated their desire to eat on a one-to-10 scale from “not at all” to “very much.” After they drank the liquids, brain scans were performed while the subjects looked at images of food and of neutral objects, such as buildings or baskets.  While participants looked at the images, they rated their hunger using the scale. The volunteers were then presented with images of high-calorie foods and asked whether they would like to have the food now, or a monetary award a month later instead.

The study, published in the journal PNAS, found that compared with glucose, consuming fructose produced greater responses to food cues in the orbital frontal cortex of the brain, a region that plays an important role in reward processing.

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Princeton Study: Measles Vaccine Offers Widespread Protection

The measles vaccine may offer protection from a wide range of diseases, including some that could be deadly, according to a new study from Princeton University’s Woodrow Wilson School of Public and International Affairs and Department of Ecology and Evolutionary Biology. The study was recently published in Science, an academic journal.

“Our findings suggest that measles vaccines have benefits that extend beyond just protecting against measles itself,” said lead author Michael Mina, a student at Emory University School of Medicine who worked on the study as a postdoctoral researcher at Princeton. “It is one of the most cost-effective interventions for global health.”

Before the study, it was widely believed that a case of measles suppressed a child’s immune system for about 30 days, thereby creating a month-long gap in which a child may be vulnerable to other potentially fatal diseases. But the Princeton-led research team shows that the period of vulnerability may last for up to three years after a child develops measles.

And therefore, a vaccine that protects children against measles may also indirectly protect them from contracting other illnesses.

“In other words, if you get measles, three years down the road, you could die from something that you would not die from had you not been infected with measles,” said C. Jessica Metcalf, co-author and assistant professor of ecology and evolutionary biology and public affairs at Princeton.

As part of the study, researchers studied the deaths of children in Europe and the U.S., in both pre- and post-vaccine eras. The team tracked the circumstances around the deaths.

“Reducing measles incidence appears to cause a drop in deaths from other infectious diseases due to indirect effects of measles infection on the human immune system,” Bryan Grenfell, a Princeton professor and a member of the research team.

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