The Quest

Do real men eat soy? Perhaps. But if they want to become fathers, they may want to limit their tofu intake. A new study shows that downing soy products may lower sperm count. The reason, according to the research published in the journal Human Reproduction (pdf): soy beans contain high amounts of phytoestrogens, organic compounds that mimic the female hormone estrogen in the human body and, in animal studies, have been shown to reduce testosterone levels. Lead study author Jorge Chavarro, a research fellow in the Department of Nutrition at the Harvard School of Public Health,and his colleagues found that men who ate at least half a serving a day of soy had, on average, 34 million fewer sperm per milliliter than those who skipped it. But Chavarro doesn’t recommend you give up the soy burgers—at least not yet. He notes that the study was limited (99 men) and that more research is needed to prove that tofu actually reduces male fertility.

Snap-happy dieters reap benefits

•                   05 September 2008
• From New Scientist Print Edition. Subscribe and get 4 free issues.       

  WATCHING what you eat really does help, at least if you do it through a camera lens. That’s the conclusion of a study of dieters’ eating habits comparing the effect of written food diaries with taking a snapshot of each meal.

Food diaries track food consumption during weight loss programmes, but now taking a snapshot of each meal is replacing the laborious task of writing down everything you eat. To see if photos might also prompt healthier eating, Lydia Zepeda and David Deal at the University of Wisconsin-Madison told 43 people to record what they ate for one week in words and as pictures.

When they quizzed the volunteers, photo diaries seemed to be the most effective. Not only did they provide powerful visual documentation of snack binges, they also triggered critical evaluation at just the right time - before the food was eaten (International Journal of Consumer Studies, DOI: 10.1111/j.1470-6431.2008.00725.x). "I had to think more carefully about what I was going to eat because I had to take a picture of it," was a typical response.

In contrast, written diaries are often completed long after the meal and do not create as powerful a reminder of the quantity and quality of the food that was eaten.

"Nutritionists see diaries as recording tools. Now they should explore the role of photo diaries as intervention tools," says Zepeda.