<Tr> <Td> Moderate risk of developing heart disease, high blood pressure, stroke, diabetes </Td> <Td> 23 to 27.5 </Td> </Tr> <Tr> <Td> High risk of developing heart disease, high blood pressure, stroke, diabetes </Td> <Td> over 27.5 </Td> </Tr> <P> In 1998, the U.S. National Institutes of Health and the Centers for Disease Control and Prevention brought U.S. definitions in line with World Health Organization guidelines, lowering the normal / overweight cut - off from BMI 27.8 to BMI 25 . This had the effect of redefining approximately 29 million Americans, previously healthy, to overweight . </P> <P> This can partially explain the increase in the overweight diagnosis in the past 20 years, and the increase in sales of weight loss products during the same time . WHO also recommends lowering the normal / overweight threshold for South East Asian body types to around BMI 23, and expects further revisions to emerge from clinical studies of different body types . </P>

When was the last time the bmi chart was updated