More complicated testing includes measurement of lung volumes; lung, chest wall, and respiratory system compliance (which requires measurement of esophageal pressure); and complete cardiopulmonary exercise testing.
The suggested serving size of sour cream is 1 tbsp. This serving size contains 31 calories, and 27 of those calories are from fat. Sour cream has less than 1 g of carbohydrates and 3 g of fat, which is 5 percent of the recommended amount per day. There are nearly 2 g of saturated fat, which is 9 percent of the amount recommended per day.
When a tortilla alone can run you 300 calories, and a dollop of sour cream about 115, staying under 1000 can be challenging (forget about adding chips and guacamole). The Times found that just 25 out of 1,200 burritos fell below 700 calories.