These are the most popular and best usenet newsgroups that focus on diabetes, as well as diabetes-related health issues such as high-blood pressure, weight, cholesterol and heart disease.
- alt.food.diabetic 
Focuses on diabetic cooking and recipes.
- alt.health.diabetes 
Focuses on diabetic health.
- alt.support.diabetes 
Support group for diabetics.
- misc.health.diabetes 
Focuses on miscellaneous diabetes-related health issues.
- alt.support.diabetes.kids 
Focuses on type 1 diabetes and children with diabetes.
- de.sci.medizin.diabetes 
German language newsgroup.
- es.charla.enfermedad.diabetes 
- sci.med.diseases.diabetes 
Focuses on diabetes related science and medicine.
- alt.support.heart 
Focuses on heart-related health.
- alt.support.heart.children 
Focuses on childhood heart related issues.
- alt.support.obesity 
Focuses on obesity and weight.
- alt.support.kidney-disease 
Focuses on kidney disease.
- alt.support.kidney-failure 
Focuses on kidney disease and kidney failure.
- sci.med.diseases 
Focuses on the science and medicine relating to disease.
- alt.food.fat-free 
Focuses on fat-free recipes, food and cooking.
- alt.food.low-fat 
Focuses on low-fat recipes, food and cooking.
- rec.food.veg.fatfree 
Focuses on vegetables and vegetable recipes, food and cooking.
These are a few of the usenet newsreaders available to help get you hooked into usenet. You can find a great listing on Wikipedia at this link: Comparison of Usenet newsreaders