Letting your diet slip linked with 34 per cent increased risk of type 2 diabetes

A decrease in diet quality over four years has been linked a 34 per cent increase in the risk of type 2 diabetes, according to a study by researchers at Harvard.
The study followed a total of 124,607 adult participants that did not have diabetes at the start of the study. The participants were drawn from three US long-term health monitoring programs, the Nurses’ Health Study I and II, and the Health Professionals Follow-up Study.
The participants had the quality of their diet monitored initially during a four-year period and were then monitored for incidence of diabetes over the next 20 or more years.
Diet quality was assessed using the Alternate Healthy Eating Index (AHEI) score. The AHEI quantifies diet quality by measuring a number of factors including servings of vegetables per day, servings of fruit per day, ratio of white meat to red meat, ratio of polyunsaturated fats to saturated fats, plus fibre, trans fat and alcohol intake.
Unhealthy factors, such as trans fats intake, result in lower diet quality scores whereas healthy factors, such as fibre intake, result in a higher score.
The results of the study showed that a decrease in diet quality of more than 10 per cent over four years was linked to a 34 per cent increased risk of type 2 diabetes.
By contrast, when diet quality increased by over 10 per cent during the four-year period, the risk of type 2 diabetes reduced by 16 per cent.
An interesting further finding was that change in body mass index (BMI) only explained 32 per cent of the new cases of diabetes. This backs up previous findings that have shown that people can develop type 2 diabetes at lower BMI levels if the quality of their diet is poor.
The researchers concluded their study noting that, “Improvement in overall diet quality is associated with a lower risk of type 2 diabetes, whereas deterioration in diet quality is associated with a higher risk.
And that, “The association between diet quality changes and diabetes risk is only partly explained by body weight changes.”
The study has been published online, ahead of print, by the Diabetes Care journal.