Nerve damage (neuropathy) that can trigger pain or numbness in the limbs, hands, and feet is poorly understood even though it affects about 60 percent of people with diabetes. But research is shedding light on one potential factor: triglycerides in the blood. Over a one-year study, diabetic neuropathy got worse in people with higher triglycerides than in those with lower levels, although it’s not clear that triglycerides caused the nerve damage. Keeping blood glucose under control is generally recognized as the best way to prevent neuropathy and is associated with lower triglyceride levels. But this study suggests that treating aberrant blood fats may also benefit the nerves. Triglyceride levels should be less than 150 mg/dl. Lifestyle changes like eating less saturated fat and exercising more can help keep triglycerides under control. 
Source: Diabetes, published online May 1, 2009