The researchers also found that caffeine did not affect how the participants perceived their appetites, and that body mass index (BMI -- an estimate of body fat based on height and weight) had no effect on how caffeine affected appetite or how much people ate.

Can breakfast help you slim down? WebMD has the answers.

Feeling dizzy or lightheaded when you stand up may be a risk factor for stroke and dementia years down the road, a new study reports.

Prescribing of opioids remains high largely because of a medical culture that evolved over many years, said study lead researcher Molly Moore Jeffery, a health economist at the Mayo Clinic, in Rochester, Minn.

Dehydration has long been known to slow physical performance. Now there's evidence that too little water can hurt cognitive performance, too, making complex thinking tasks harder.

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In the Paleo era, people ran around all day and rarely lived past 40, so their risk of developing the so-called diseases of civilization is unknown.