Foods that are low in carbohydrates are a smart choice for people who have certain medical conditions. Carbohydrates are broken down by the digestive system as sugar, which makes high-carb foods a risky bet for diabetic patients. Low-carb pasta is less likely to cause blood sugar spikes than regular pasta since its carbohydrate content is made up mostly of fiber, which the body does not convert into glucose. Of course, if you have any condition that affects your diet, you should always consult with your doctor before consuming new foods.
Most low-carb diet authors don't recommend bothering with it. Even many of those who think a ketogenic diet is a good thing just assume that a very-low-carbohydrate diet (under about 50 net grams of carbohydrate) is ketogenic. On the other hand, many people have found that monitoring their ketones, at least for a while, provides valuable information.