The Association of American Feed Control Officials (AAFCO) provides standards that guides many commercial pet food companies. This level of supervision does not occur with homemade food and this can predispose them to a variety of deficiencies and imbalances. One study analyzed the nutritional content of three homemade diets (BARF, Ultimate and Volhard) and two commercial raw food diets (Steve's Real Food and Sojourner Farms) and compared it to the AAFCO standards, showing nutritional imbalances in the homemade diets. Three of the diets had inadequate calcium-to-phosphorus ratios, which may lead to hyperparathyroidism and fibrous osteodystrophy in puppies. As well, homemade diets were proven to have deficiencies in vitamin D, important for bone health by facilitating calcium absorption in the gut, which contribute to storage in bone, and vitamin E, which improves overall immune function by reducing oxidative stress. Oxidative stress happens when free radical formation, which is a natural process, excess the body's ability to destroy them, resulting in cellular damage and inflammation. Antioxidants improve the destruction process by scavenging the free radicals. Many macro-minerals were also undersupplied such as, Zinc, Potassium and Sodium in the homemade puppy diet.  Another study analyzed 95 homemade BARF diets and found that 60% of these diets had an imbalance in either one, or a combination of calcium, phosphorus, vitamin D, iodine, zinc, copper, and vitamin A.