In which case your options would appear to be a) buy what fits your criteria from what is available for sale. b) learn to cook. c) pay someone to cook for you. There's huge variation in what people consider "good nutritious food". Regardless of if they are diabetic or not. Such foods (other than basic ingredients) are likely to not fit well with the business models of supermarkets or chain restaurants. Which tends to be more selling what most people will buy for the most markup.