South Asian children may need to be offered diet and exercise advice before the age of 10 to cut their risk of diabetes in later life, UK researchers believe.
Dr Peter Whincup and colleagues from the division of community health services at the University of London studied 4,796 children between nine and 10 years old.
The group included 1,306 South Asian, 1,153 white European and 1,215 black African-Caribbean children.
The researchers found that ethnic differences in type-2 diabetes precursors were apparent in this group, including HbA1c, fasting insulin, triglyceride and CRP.
They suggest that these differences offer opportunities for early prevention, with the aim of encouraging physical activity, improving nutrition and preventing obesity.
The differences in type-2 diabetes precursors mostly followed adult patterns and were not accounted for by higher adiposity levels among South Asians, as assessed using skinfolds and bioimpedance.
Fasting insulin levels were 29 per cent higher in South Asian than white European children, triglyceride levels were 14 per cent higher and CRP levels were 43 per cent higher.
The researchers said the findings showed for the first time that 'ethnic differences in type-2 diabetes precursors are present in apparently healthy children at the end of the first decade'.
Black African-Caribbean children also had higher levels of HbA1c, insulin, and CRP than white Europeans. However, the differences were not as marked as those between South Asian and white European children.
Black African-Caribbean children had higher HDL-cholesterol and lower triglyceride levels than white Europeans; adiposity markers were not increased.
The researchers said the results imply that ethnic differences in type-2 diabetes are persisting in UK-born South Asians.
They added: '(The results) also suggest that at least some of the aetiological factors responsible for ethnic differences in insulin resistance and type-2 diabetes are operating well before adult life, potentially offering opportunities for early prevention.
'There is a particularly urgent need for preventive measures in high-risk ethnic groups, in which the benefits of prevention are potentially greater.'