-- by Jane O'Brien, BBC News:

Thirty per cent of Americans are getting fewer than six hours sleep a night, far short of the recommended eight hours that doctors say are optimal for good health.

Now a new survey reveals that sleep times vary among different ethnic groups, with African-Americans getting at least 34 minutes less sleep than Asians, Hispanics or Caucasians.

The National Sleep Foundation's 2010 Sleep in America poll is the first to study sleep patterns among ethnic groups. It raises some important questions about why different sections of society are sleeping less than others.

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