shown some foods that pass AAFCO's feeding trials are still not suitable for long-term use and estimated that of 100 foods that pass the nutritional analysis, 10 to 20 would not pass the feeding trials. Although maximum levels of intake of some nutrients have been established because of concerns with overnutrition, many still lack a maximum allowed level and some contains large disparity between maximum and minimum values. The NRC accepts that despite ongoing research, large gaps still exist in the knowledge of quantitative nutritional information for specific nutrients. Some professionals acknowledge the possibilities of phytochemicals and other vital nutrients that have yet to be recognized as essential by nutritional science. With such broad guidelines and loose feeding trial standards, critics argue that the term "complete and balanced" is inaccurate and even deceptive. An AAFCO panel expert has stated that "although the AAFCO profiles are better than nothing, they provide false securities." Certain manufacturers label their products with terms such as premium, ultra premium, and holistic. Such terms currently have no official definitions. The AAFCO is currently considering defining some of the terms. However, the terms "natural" and "organic" do have definitions; e.g., organic products must meet the same USDA regulations as for organic human food. Canada In Canada, products that pass the Canadian Veterinary Medical Association (CVMA) Pet Food Certification Program, which involves a feeding trial, carry a CVMA label on their packaging. Participation in the program is voluntary. The program was discontinued at the end of 2007. There is no government regulation of pet food manufactured in Canada. However, imported pet food does receive stringent oversight. European Union In the European Union, pet food is regulated by the same harmonised standards across the EU, via the Feeding Stuffs Act. All ingredients used for pet food have to be fit for human consumption according to EU requirements. But regulations require that pet food that contains by-products be labelled as "Not for human consumption" even though such by-products have to be derived from animals declared fit for human consumption. Raw pet food has to be labelled "Pet food only". Products meant for daily feeding are labelled "complete feedingstuff" or "complete petfood" or other EU languages equivalent. Products meant for intermittent feeding are labeled "complementary feedingstuff or "complementary pet food" while products with an ash content of over 40% are labeled "mineral feedingstuff". Ingredients are listed in descending order by weight.