Background and aims:. T2D is postulated to be an important aetiological factor for lumbar disc degeneration (LDD), which itself has a well documented relationship with low back pain. Obesity increases risk of both T2D, low back pain and LDD. Connective tissue modification has been reported in hyperglycaemia, but the epidemiology of LDD in T2D has not been described to date. Methods and results:. A population sample of unselected same-sex adult twin pairs was studied who had attended a spine MR study and completed general health questionnaires defining T2D by self-report. LDD had been coded as the sum of five lumbar discs coded (0–3) for each of height, signal intensity, disc bulge and anterior osteophytes. Risk factors for LDD included age, body-mass index (BMI), sex, alcohol consumption and smoking. Mean age of the 1011 participants = 54 years (sd=8), mean BMI=25 kg/m. 2. (sd=4), 95% female. The prevalence of T2D was 6%. Twins with T2D had increased BMI (27 vs 25 kg/m. 2. , p<0.001) and were older (59 vs 54 years, p<0.001). LDD score in T2D was significantly higher in diabetic cases than controls (14.9 vs 13.1, p=0.04) in univariable analysis. In multivariable analysis inclusion of age and BMI abrogated the effect of T2D. Conclusions:. We did not find evidence that T2D is an independent risk factor for LDD. This study had 0.8 power at 0.05 significance level to detect a difference of 2.1 LDD units. Age and BMI accounted for the increased LDD observed in T2D