Gorske claims that on his first trip to McDonald's in April, 1972 he purchased and ate three Big Macs at lunch time. He then returned two more times that day to consume a total of nine Big Macs the same day he discovered the sandwich. He further claims to have eaten 265 Big Macs in the following month, an average of 8.5 Big Macs per day. If true, this would be equivalent to over 4,600 calories and 247 grams of fat daily, for a total of 143,100 calories and 16.9 pounds of fat in one month. He also claims to drink almost nothing but Coca Cola and, according to Super Size Me, he rarely eats the fries. At first, Don kept all the boxes of Big Macs he ate in the back of his car.

In 2003 Don Gorske ate 741 Big Macs, an average of 2.03 Big Macs per day. Despite maintaining what many would consider to be an unhealthy diet, Gorske is 6 feet (1.83 m) tall, 180 pounds (82 kg), and claims a cholesterol level of 140. However, his claimed average daily consumption of two Big Macs amounts to only 1080 calories, according to the nutritional information published by McDonald's[1], although this does not take into account his energy intake from fluids. In comparison, the USDA recommends about 2,200 calories per day.[2] Thus, whilst Gorske consumes mainly calorie-rich food, he maintains a stable weight by eating a lesser volume of food than the average American.

On August 17, 2008, Gorske ate his 23,000th Big Mac at his favorite McDonald's restaurant in Fond du Lac.