You Should Know

July 2017 Issue




Potato Redemption

Maligned for years by dieters and the popular press, white potatoes have been blamed for increasing overweight, obesity, and type 2 diabetes risk. Could the world’s third largest food crop, behind rice and wheat, truly be the culprit of ill health? EN takes a closer look at the science.

Potatoes

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Don’t fear the humble potato, which is a nutrient powerhouse.

Nutrition

Potatoes have been criticized for having little nutritional value, despite providing many essential nutrients (see Potatoes’ Hot Nutrients), most notably potassium and fiber, which were identified as nutrients of public health concern per the 2015 Dietary Guidelines for Americans. Potatoes also contribute vitamin C, magnesium, vitamin B6, niacin, and thiamin, as well as carotenoids and polyphenols.

Glycemic Index (GI)

The starchy vegetable’s reported high GI has been tapped as the perpetrator of weight gain and diabetes. Foremost, GI alone is not a sole predictor of weight gain or diabetes. Several influencers are at work in the progression of weight gain and diabetes, including overall diet, total caloric intake and expenditure, and genetics. Further, the GI of potatoes varies broadly and is dependent on many factors, such as cooking method (baked has lower GI than boiled) and how it is consumed (eating with skin lowers GI). Cooking and reheating or consuming them when cooled also lowers GI, attributed to higher presence of resistant starch. Consuming potatoes with other foods, such as cheese, also alters the GI. Finally, potatoes’ high satiety index may help with appetite control.

Resistant starch is a complex carbohydrate found in potatoes. It passes through the small intestine undigested, then moves into the large intestine where it is fermented by gut bacteria. Resistant starch is linked with benefits for body weight, gut health, and blood lipid and glucose levels.

The Bottom Line

Pay less heed to their GI, and instead consume satisfying fresh potatoes with the skin for more fiber, potassium, and other nutrients. Minimize high-calorie accompaniments, such as butter, cheese, and sour cream. Try low-fat Greek yogurt or low-fat cottage cheese toppings. Enjoy processed potato products with added calories and fat (i.e., French fries and potato chips) in moderation.

Potatoes' Hot Nutrients 

Food 
Nutrients

Baked Potato,
Flesh & Skin

Baked Potato,
Flesh only

Calories 93 93
Protein 2.5 g (5% DV) 2 g (4% DV)
Tot. Carbs 21 g (7% DV) 21.5 g7(% DV)
Tot. Fat <0.5 g (0% DV) 0.5 g (0% DV)
Fiber 2.2 g (8% DV) 1.5 g (5% DV)
Potassium 535 mg (11% DV) 391 mg (8% DV)
Magnesium 28 mg (7% DV) 25 mg (6% DV)
Vitamin C 10 mg (11% DV) 13 mg (14% DV)
Iron 1.08 mg (6% DV) 0.35 mg (2% DV)
Folate 28 mcg (7% DV) 9 mcg (2% DV)
Vitamin B6 0.311 mg (18% DV) 0.3 (18% DV)
Source: USDA; Note: g=gram, oz=ounce, mg=milligram, mcg=microgram, DV=Daily Value