Cholesterol (or lipid) problems in people with type 1 diabetes are usually related to the lack of insulin.

• Lack of insulin increases the level of triglycerides. Normally, insulin makes a certain enzyme remove triglycerides from the blood. When insulin is used to treat high blood sugar, the triglyceride level goes back to normal.
• A lack of insulin (and the high blood sugar that results) raises the level of "bad" cholesterol (LDL, or low-density lipoprotein). It returns to normal when insulin is given.

Data from the Diabetes Complications and Control Trial (DCCT) showed that people with type 1 diabetes had cholesterol levels similar to people without diabetes when their blood sugar levels were kept within a near-normal range.¹

This does not apply to people with nephropathy, because once the kidney starts losing even small amounts of protein, cholesterol problems begin to develop.