When it comes to their reputation among nutrition experts, potatoes are a mixed bag, no pun intended. Some experts, such as Dr. John McDougall, endorse a predominately starch-based diet that includes abundant quantities of potatoes. Others, including Walter Willett, contend that potatoes are nutritionally on par with white flour and as such should not even be included in the vegetable category. Who should we believe? Looking at your daily needs and how a potato might satisfy them will show how they stack up, nutritionally speaking.
A Healthy Diet
A healthy diet supplies all essential amino acids in amounts required by the human body, according to the textbook "Biochemistry." You also need the recommended intake for fiber, vitamins and minerals. In addition, eating enough calories to meet your metabolic needs is important, and the average 130 lb., moderately active individual requires roughly 2,000 calories per day.
Protein is required in the diet to help strengthen your cells and power reactions involving enzymes. The Institute of Medicine suggests a protein intake of 46 g per day for the average female. Consuming 14 medium red potatoes would give you 2,000 calories and 56 g of protein, according to the USDA's National Nutrient Database for Standard Reference. Thus, as far as your protein requirement is concerned, you could live off potatoes.
While not a source of calories, fiber is essential to promote proper digestive function. It also helps to lower blood cholesterol and control blood sugar, according to MayoClinic.com. Women should aim to consume 25 g of fiber per day and men should shoot for 38 g. Two thousand calories-worth of potatoes contains nearly 45 g of fiber, which exceeds the daily requirement.
The Other "Stuff"
Eating nothing but potatoes all day would meet your caloric, protein and fiber requirements. As for the 20 essential vitamins and minerals, a diet of exclusively potatoes meets or exceeds the daily requirement for vitamins B-5, B-6 and C, copper, iron, magnesium and manganese, niacin, phosphorus, potassium, thiamin and folate. However, such a diet would leave you deficient in vitamins A, B-12, D and E, as well as calcium, riboflavin, selenium and zinc. Deficiencies in these nutrients are associated with an array of symptoms and conditions, making supplementation a requirement, either with a multivitamin or other foods. Potatoes alone are good, but a balanced diet is better.