These findings were presented at this week’s Experimental Biology conference in Anaheim, Calif. They showed that people who ate organic cookies labeled as “organic” believed that their snack contained 40% fewer calories than the same cookies that had no label, according to Jenny Wan-Chen Lee, a graduate student with the Cornell Food and Brand Lab.

“An organic label gives a food a ‘health halo,’ said coauthor, Brian Wansink, Cornell professor and author of the book, Marketing Nutrition. It’s the same basic reason people tend to overeat any snack food that’s labeled as healthy or low fat. They underestimate the calories and over-reward themselves by eating more.”

The study even identified two personality types most likely to make these low estimates – people who claim to “usually buy organic foods,” and those who typically read labels for nutritional information.

What if you don’t want to overeat an organic food?

“Take your best guess at its calorie count. Then double it. You’ll end up being more accurate, and you’ll probably eat a lot less,” explained Wansink.

Source:
Tom Rushmer
Cornell Food & Brand Lab

Researchers from the newly founded Max Planck Institute for Biology of Ageing in Cologne have studied whether health benefit stem from a reduction in specific nutrients or calorie intake in general by manipulating the diet of female fruit flies. The fruit flies were fed a diet of yeast, sugar and water, but with differing amounts of key nutrients, such as vitamins, lipids and amino acids. The scientists were able to show that longevity and fertility are affected by a combination of the type and amount of amino acids; whilst varying the amount of the other nutrients had little or no effect. Furthermore, the researchers found out in previous studies that levels of a particular amino acid – methionine – were crucial to increasing lifespan without decreasing fertility. By carefully manipulating the balance of amino acids, both lifespan and fertility were maximised. For the first time, this indicates that it is possible to extend lifespan without wholesale dietary restriction and without lowering reproductive capacity.

As the effects of dietary restriction on lifespan is evolutionary conserved – observed in different organisms – researchers believe that the essential mechanisms apply to it as well. Even though the human genome has about four times the number of genes as the fruit fly genome, there are many similarities on a genetic level, allowing these results to be of significance for humans as well.

Original work:
Richard C. Grandison, Matthew D. W. Piper & Linda Partridge
Amino-acid imbalance explains extension of lifespan by dietary restriction in Drosophila
Nature, December 3, 2009, doi:10.1038/nature08619

Source: Katharina Möller
Max-Planck-Gesellschaft