A study, Effect of Eucaloric High- and Low-Sucrose Diets With Identical Macronutrient Profile on Insulin Resistance and Vascular Risk, published in the American Diabetes Association (ADA) journal, Diabetes, investigated the relationship between sugar intake and risk of developing diabetes.
What's fascinating, and disturbing at the same time, is how this study made it through peer-review without questioning the conclusion that a high-sucrose intake as part of a balanced, eucaloric, weight-maintaining diet had no detrimental effect on insulin sensitivity in healthy nondiabetic subjects compared with a low-sucrose diet; when the data clearly shows subjects at baseline had a normal fasting blood glucose level of 4.8mmol/L (86.4mg/dL) which rose to the ADA defined pre-diabetic level, 100-125mg/dL, rising to 5.6mmol/L (100.8mg/dL) in just six weeks.
The subjects' HOMA-IR score also climbed from a reported 1.99 at baseline to 2.14 when assigned the diet containing 10% sucrose, and to 2.39 when assigned the diet containing 25% sucrose, after just six weeks on either diet. The HOMA-IR, you'll recall, is the Homeostasis model assessment for Insulin Resistance. A value greater than 3.8 is indicative of insulin resistance. It is calculated by using the formula: HOMA-IR = insulin (µU/mL) × glucose (mmol/L) ÷ 22.5.
Over a period of just six weeks, the subjects in this study experienced a rise in their HOMA-IR scores and their fasting blood glucose, yet the researchers concluded "a high-sucrose intake as part of a balanced, eucaloric, weight-maintaining diet had no detrimental effect on insulin sensitivity in healthy nondiabetic subjects compared with a low-sucrose diet."
Even the headlines are trying to convince us this study somehow proves sugar doesn't cause diabetes - Sugar not linked to diabetes rise, suggests study.
In the above article we're told, "Writing in Diabetes, Dr. Hunter and his co-workers report that no weight changes were recorded for either group, and that there was no significant differences in glucose uptake and production. Additionally, no significant adverse effects for a number of other metabolic and physiologic parameters were observed between the groups, he said, such as elasticity of the arteries, and glycaemic profiles."
In this study, a high-sucrose intake as part of an eucaloric, weight-maintaining diet had no detrimental effect on insulin sensitivity, glycaemic profiles, or measures of vascular compliance in healthy non-diabetic subjects," said the researchers."
It is likely that other dietary factors such as excess calories and lifestyle factors such as physical inactivity and weight gain may be more important than carbohydrate type," said Hunter."
How exactly does a finding, completely at odds with the data, get published? I have to wonder, are these conclusions and subsequent headlines because "This study was supported by an unrestricted research grant from The Sugar Bureau and Suikerstichting, the Netherlands."?
Let's hypothetically say the source of funding did somehow influence the conclusions for a moment - shouldn't the peer-review process, prior to publication of the paper, caught that the data showed progression to pre-diabetes in healthy subjects in just six weeks?
Seriously - it took me less than five minutes to see the red flags - both missing and ignored data.
The missing data red flag - in the study, the researchers calculated and included the baseline HOMA-IR yet did not do so in the final data or mention the HOMA-IR after the two diets in the paper. Why?
The ignored data red flag - the rise in fasting blood glucose from baseline to the six week endpoint in the two diets. Why?
I'm no expert in diabetes, but even I know that rising fasting blood sugars that rise from normal to pre-diabetic levels, and an increase in HOMA-IR, in just six weeks, is not a good thing; and certainly not indicative that the diet studied is benign, having no effect on the metabolism of glucose.
But, hey, we're told once again sugar doesn't cause diabetes.
You want to know something? It's true - it doesn't. It's not the sugar per se, it's the excessive total carbohydrate that includes sugar and starch in the diet.
In both diets subjects increased total carbohydrate from 280g a day (17g of fiber) to 437g a day. After just six weeks, the difference between the 437g carbohydrate diets with 10% sucrose or 25% sucrose was insignificant, but the difference from a baseline diet with 280g of carbohydrate compared with the trial diets containing 437g of carbohydrate should be a wake-up call for anyone investigating how insulin resistance and pre-diabetes, which places one on the road to develop diabetes, can happen in just six weeks.
It's right there in the data - fasting blood glucose rose in six weeks from normal to pre-diabetic -- and not one researcher or peer-reviewer saw fit to highlight that fact.
Ignore the data at your own risk.