Since potatoes are a simple carbohydrate and affect blood sugar they can impact triglycerides, which in turn could raise total cholesterol. Potatoes are a perfectly good vegetable, but a lot people go overboard, so watch the amount and be sure to eat them in a meal that contains protein to regulate the blood sugar spike.
You can learn more about triglycerides in this post: Triglycerides: Why they matter and how to lower them.
All the best,
Lisa Nelson, RD, LN
The Heart of Health - Heart Health and Weight Loss Tips
Your comment is correct however potatoes are not a veggy, they come from the root family.
By definition, vegetables are the edible parts of the leaf, stem and/or roots of the plant. Since potatoes are part of the stem (tubers), they are are vegetable. Sorry to disagree jBar, but you can look it up.