The review did not include research on valerian, an herb commonly used to treat insomnia and anxiety, although one study did look at a supplement that combined valerian and St.

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Duffy MacKay, vice president for scientific and regulatory affairs at the Council for Responsible Nutrition, a trade group for the supplement and energy-drink industries, called the study "a new, emerging hypothesis, " but said the researchers were drawing large conclusions from small studies of mice, bacteria and human biomarkers.

WSJ: New Health Culprit Carnitine Found in Red Meat

Duffy MacKay, vice president for scientific and regulatory affairs at the Council for Responsible Nutrition, a trade group for the supplement and energy drink industry, called the Nature study "a new, emerging hypothesis, " but said the researchers were drawing large conclusions from small studies of mice, bacteria and human biomarkers.

WSJ: New Health Culprit Carnitine Found in Red Meat

July 25, 2006 A new study finds women who take the hormone supplement testosterone to reduce menopausal symptoms are at increased risk of breast cancer.

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Since experimental evidence has suggested that antioxidants consumed orally, such as beta carotene, can reduce signs of sun-related skin damage, the study also looked at whether a daily 30-milligram beta carotene supplement could protect against skin aging.

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In the study, when a longtime omnivore consumed an eight-ounce steak and a carnitine supplement, both his bacteria and TMAO levels rose considerably.

WSJ: New Health Culprit Carnitine Found in Red Meat

In the study, when longtime meat-eaters consumed an eight-ounce steak and a carnitine supplement, their bacteria and TMAO levels rose considerably.

WSJ: New Health Culprit Carnitine Found in Red Meat