BIOLOGY
New research finally identifies why garlic is good for you. While the beneficial health effects of garlic consumption have been known for centuries, researchers at the University of Alabama at Birmingham believe they have solved the mystery of how it works. Digestion of organosulfur allicin, garlic's main ingredient, produces hydrogen sulfide, which in turn signals the relaxation of blood vessels in the body increasing blood flow. The new study, by biologist David Kraus and colleagues, was the first to use innovative techniques to measure the amount of hydrogen sulfide produced by garlic consumption. Although some previous research showed no effect from garlic consumption, other studies have suggested that people who eat more garlic tend to suffer less from heart disease. Researchers hope the new findings can help to standardize dietary garlic supplements.
BOTTOM LINE: "Garlic is good for you, and we are beginning to understand why," says Kraus.
CAUTIONS: The study did not address the possibility of side effects from extensive garlic consumption.
WHAT'S NEXT: Researchers intend to further investigate the chemistry of hydrogen sulfide in the body.
WHERE TO FIND IT: Proceedings of the National Academy of Sciences, Oct. 15.
LAUREN A. MARCUS
ANTHROPOLOGY
Man's first clambake: 160,000 BC
Our distant ancestors learned to survive near the sea much earlier than previously thought, a new study finds. Researchers, including Curtis Marean of the Institute of Human Origins at Arizona State University, found evidence near the coastal cliffs of South Africa suggesting that humans from more than 160,000 years ago began to eat food from the ocean, such as shellfish - pushing back the known use of marine resources by tens of thousands of years. The team also discovered small stone blades and red pigments, suggesting that these humans may have been able to fashion tools and use colors symbolically. According to Marean, the team decided to explore the cliffs of South Africa after determining that this area of land was likely above sea level 150,000 years ago, making it habitable for humans. After the investigators began to find evidence for human habitation, they turned to advanced techniques, such as optically stimulated luminescence and uranium dating, to find out exactly how old the discoveries were - methods that Marean says are relatively precise ways to determine the age of an archeological specimen. These findings make sense, investigators argue, as the harsh, dry climate of inland Africa may have pushed humans to seek solace and useful resources near the ocean.
BOTTOM LINE: This study pushes back the story of our ancestry to 160,000 years ago, when early modern humans had already begun to settle on the coast and gather food from the ocean.
CAUTIONS: The exploration was limited in size, mostly because the researchers hope to save some of the land so that future groups with more advanced technology will be able to return to the site to gather more information.
WHAT'S NEXT: Another excavation is already underway to gather more evidence on coastal-dwelling humans.
WHERE TO FIND IT: Nature, Oct.18
SUSHRUT JANGI
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