Throughout our day, most of us go through many different emotions - happiness, sadness, anger, boredom, and everything in between. Now, a new worldwide study shows that happiness also fluctuates over the course of our lifetime, tending to bottom out in middle age, with older and younger people being the happiest. For a while now, we've known that there's a relationship between well-being and age. Researchers began to wonder whether they could uncover a pattern between age and happiness by looking at surveys conducted throughout the world. Coauthors David Blanchflower of Dartmouth College and Andrew J. Oswald of the University of Warwick in England, examined pooled data from 80 countries, in which more than 2 million people were asked questions about satisfaction with their lives. In 72 of the 80 countries, they found a similar "U-shaped" pattern, in which happiness declined among people in their mid- to late 40s. Some countries, especially developing countries, did not have this pattern, which might be because of relatively small data sets or different life expectancies. Why people in their middle age are less happy is unclear - "It could be something biological," Blanchflower suggests, "or perhaps we just begin to realize the how feasible our aspirations really are."
BOTTOM LINE: After surveying more than 2 million people worldwide, an intriguing pattern emerges: Happiness bottoms out in our middle age before climbing again.
CAUTIONS: The study doesn't uncover why this effect should occur - it is simply a documentation of the observed pattern.
WHAT'S NEXT: Researchers plan to continue studying international evidence of well-being, and possibly create a "gross domestic happiness" index to measure overall well-being in countries.
WHERE TO FIND IT: Social Science & Medicine
Higher chemical level might be linked to baby products
Baby products like shampoo, lotion, powder, diaper cream, and wipes may increase the levels of phthalates in infants, a new study finds. Phthalates are chemicals used to make plastics more flexible, but there is increasing evidence that they pose health risks. They can be naturally eliminated from the body, but past research has shown that high concentrations in breast milk alter reproductive hormone levels in infants. Phthalates in dust have been associated with eczema, allergies, and asthma in children. A group of researchers, led by Dr. Sheela Sathyanarayana of the University of Washington at Seattle, recently tested urine samples of 163 infants between 2 and 28 months old and asked the mothers if they had used any baby products within the previous day. They found that at least one kind of phthalate was present in all infants and 80 percent had seven or more different kinds in their urine. But higher concentrations of these chemicals were present in those infants whose parents had applied baby powder, shampoo, or lotion to them in the last 24 hours. Babies less than 8 months old who had been exposed to lotion had phthalate levels five to six times higher than babies who had not been exposed.
BOTTOM LINE: Phthalates, chemicals present in cosmetics, perfumes, plastics, and toys, have now been found in a range of baby products. "We cannot restrict exposure to all phthalates but we can reduce use of baby products that may be causing increased phthalate levels in infants," Sathyanarayana said.
CAUTIONS: Federal regulations do not require manufacturers to disclose the presence of phthalates in their products and the study did not test for phthalates in the products, so it is not certain that the phthalates in the babies' systems came from these baby products.
WHAT'S NEXT: Sathyanarayana wants to study the long-term effect of phthalate exposure on humans.
WHERE TO FIND IT: Pediatrics, online Feb. 4
SENA DESAI GOPAL
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