Ask a Scientist: Are Potatoes Bad for You or Good for You?

The Scientist: Keri Glassman, R.D., is a nutrition expert and founder of Nutritious Life.

The Answer: Regular old white potatoes are not inherently bad for you. One medium potato, baked with the skin, is under 200 calories and is a great source of fiber, vitamin C, B6 and potassium. When you peel them and fry them, or smother them in butter, cheese, sour cream and bacon bits, well, that’s another story.

There’s a reason potatoes are the number one crop in the world; they’re cheap, filling and tasty. But they get a bad rap because they’re carb-heavy and look a lot like the white foods we’re often told to avoid, such as white rice and white bread. Unlike those, a whole potato is actually a whole food, which is exactly what you want to fill your diet with. In order to reap the benefits, you have to eat them whole. That means leaving on the skin, which is a concentrated source of fiber and contains beautifying phytochemicals comparable to what you find in broccoli. It also means choosing a plain steamed or baked potato instead of French fries, au gratin or any other fat-laden preparation.

At the end of the day, potatoes are still a starchy food that produces an insulin reaction, so if you overindulge, they can drive blood sugar levels down and leave you hungry again in a couple hours. You can game the system by cooking your potato and letting it cool, which increases the amount of resistant starch that stimulates satiety hormones to help keep you fuller longer. Can’t stand the idea of potatoes without a pad of hot, melty butter? Stick to antioxidant-rich, low-glycemic-index sweet potatoes instead.


Healthy Rosemary Potato Recipe

Resistant Starch to Suppress Appetite

The Beauty Benefits of Sweet Potatoes

The Lowdown on the Glycemic Index

Share with your friends

leave a comment


    You’ve got to be kidding!! Potatoes the size you quote, are NOTHING but starch bombs which turns into blood sugar faster than a large Snickers bar as demonstrated on the Dr. Oz show. The fact is 120 of the 160 calories is just that and that represents 75% of the calories in the medium baked, skin and all potato you referenced. While it also has a little sugar, the problem is truly the starch because that turns into blood glucose which glycates the entire body as it courses through the body. And only 10% of the calories are fiber that can sort of help moderate all that blood sugar potential form the starch. Let’s see 10% has to have an effect on 75%? EXTREMELY tough job which is why starchy veggies are not the best choice at all. As for “they can drive blood sugar levels down and leave you hungry again in a couple hours.” that’s very interesting because it USUALLY takes 6 hours and sometimes longer for the blood glucose to return to a better level and many times it will remain high until the morning on the fasting BG if you ate them for dinner. While your appetite might return, your BG won’t drop in any 2 hours. Regarding the cooling — the RESEARCH says it takes 12 HOURS of cooling to do that and then only 10-12% of the starch is changes to resistant. In rice, it has to be cooked with coconut oil in the water and only the same 10-12% is changed after cooling. I don’t know why you don’t seem to have a better grasp on these concepts so you could report them more accurately. If the cooling worked, cold potato salads for lo these many years would have been far safer for diabetics to eat and they simply aren’t, never were and never will be UNLESS, perhaps, you replace them with jicama which has far fewer far fewer calories 66 vs 160) for the 173 g of weight, 15 g carbs vs 37 g and oligofructose form of inulin that does not metabolize into simple sugars like glucose/fructose.