Adulthood - prevention

Peter M Clifton
Med J Aust 2002; 176 (11): . || doi: 10.5694/j.1326-5377.2002.tb04574.x
Published online: 3 June 2002

Whether fat has a role in preventing type 2 diabetes has been a vexed question for the past 50 years. There have been two very large prospective studies in women1,2 and one in men.3 The Nurses Health Study showed no relationship between the incidence of type 2 diabetes and intakes of total dietary fat, saturated fat or monounsaturated fat.1 However, polyunsaturated fat was protective and trans fatty acids were harmful, so that replacing 2% of energy from trans fatty acids with polyunsaturated fat lowered the incidence of type 2 diabetes by 40%. In Australia, where trans fatty acids are much less relevant (as they are not present in margarines and hardened fats as they are in the United States), this would translate to replacing 5% of energy from carbohydrates with polyunsaturated fat, resulting in a decrease of 37% in the incidence of diabetes. Similar but weaker findings in relation to vegetable oils came out of the Iowa Women's Study (although trans fatty acids were found to be protective).2 Some smaller studies have found a relationship between total fat intake and incidence of diabetes,4 while other studies have found a relationship between saturated fat intake and fasting glucose levels,5 fasting and postload insulin levels6 or levels of HbA1c.7 Insulin sensitivity may not be altered by fat intake, as the Insulin Resistance and Atherosclerosis Study found no such association,8 confirming the findings of most intervention studies. Only one recent study has shown that substituting saturated fat for monounsaturated fat improved insulin sensitivity in healthy men and women.9

  • Peter M Clifton

  • Clinical Research Unit, CSIRO Health Sciences and Nutrition, Adelaide, SA, Australia.



remove_circle_outline Delete Author
add_circle_outline Add Author

Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Online responses are no longer available. Please refer to our instructions for authors page for more information.