Radishes have just 3.4 g of carbs per 100 g, and are an often overlooked, but tasty and nutritious vegetable. Alfalfa sprouts, which are the sprouted seeds of alfalfa, have 2.1 g of carbs per 100 g. Try it steamed or brushed with a little olive oil and roasted in the oven or grill.
In excess, blood ketones can produce a toxic level of acid in the blood, referred to as ketoacidosis. Ketoacidosis is a known and life-threatening complication of type 1 diabetes and has been described in some cases of healthy people eating a very low-carbohydrate diet.