The Good, the Bad, and the Starchy: How Carbs in Potatoes Affect Blood Sugar

With fad diets like Keto on the rise, carbs have been under heavy fire. When trying to lose weight, starches are usually the first foods to go. But are potatoes really that bad for you? In the end, a potato’s nutrition boils down to its GI.

Glycemic index (GI) is a system that ranks a food’s ability to raise blood sugar levels. The American Diabetes Association (ADA) ranks GI as either low (55 or less), medium (56 to 69), or high (above 70). Eating foods with a low GI can help you manage your blood sugar.

Most varieties of potatoes have a high glycemic index (GI). A single baked russet potato can hit a GI of 111. To put that in perspective, the average apple has a GI of 38.

Despite ranking high in the GI department, taters are still pretty healthy. Potatoes have high levels of phenolic compounds — antioxidants that may promote health.

Studies have shown the darker a potato’s pigment, the higher its polyphenol content. There’s also a lot of diversity in the potato community. So keep in mind, some potatoes increase blood sugar more than others, depending on their GI and other nutritional elements.

How different types of potatoes stack up:

The sweetest potato for diabetes and managing glucose

Ditch the marshmallows and brown sugar, and your Thanksgiving sweet potatoes (or yams) are a diabetes-friendly treat. Sweet potatoes are loaded with:

• iron
• calcium
• magnesium
• phosphorus
• zinc
• thiamin
• calcium

Both white and sweet potatoes have similar amounts of carbs, fat, protein, and water. The basic white potato is also an excellent source of vitamin C and potassium.

However, sweet potatoes boast a lower GI and contain more fiber. Sweet spuds also have a high amount of beta carotene, which transforms into vitamin A when digested. Vitamin A is a fat-soluble vitamin that aids immune system health, vision, and organ function.

Still, they’re both made of carbs, so no matter which potato you reach for, if you’re a person with diabetes, you’ll want to watch your carb counting.

Slay that portion control

So, you know about GI, but what about glycemic load (GL)? GL helps you determine the quality of your carbs. It’s the number that predicts how much a food will raise your blood glucose levels. Figuring out glycemic load may seem complicated, but it’s pretty simple if you follow this formula:

Glycemic load = GI x Carbohydrate (g) ÷ 100 (per portion).

Starchy foods (like potatoes, processed bread, and rice) may raise blood sugar and insulin more than wholesome sugary foods such as fresh fruit. However, traditionally consumed starches (i.e. legumes, whole grain pasta, and grains) have a lower glycemic load.

But keep in mind, a low GI doesn’t always equate to a healthy food option. Take chocolate, for example. A serving of dark chocolate has an average GI of 23, but contains high levels of saturated fats. This greatly reduces its nutritional value.

When managing glucose levels, finding the right balance of GI and other health benefits is key.

The ADA has an awesome online resource for keeping your sugar spikes at a minimum. Create Your Plate is an interactive tool that helps you organize meals so you’re eating smaller portions of starchy foods and larger portions of non-starchy veggies and protein.

True or false: all carbs are the same. FALSE. In fact, carbs are broken into three groups: sugar, starch, and fiber.

• Sugar: transforms into glucose. You need glucose to function normally. However, it’s best to stick to sugars found naturally in nature, like fruits, vegetables, and milk.
• Starch: also provides the body with important levels of glucose. Starchy foods often contain vital nutrients including iron, calcium, B vitamins, and folate.
• Fiber: can improve your cholesterol and blood sugar levels. It’s also known to prevent certain diseases such as bowel cancer, heart disease, and diabetes. And let’s not forget about digestive regularity!

Each carb category serves the body in its own way. A 2017 study performed on a human test group showed a low carb diet may help with glucose control, HDL cholesterol, A1c, and managing triglycerides.

The study also showed a low carb diet can be beneficial for short-term weight loss. But do you really want to break up with bread forever? There are many pros to starchy complex carbs. Some great healthy options are:

• potatoes (especially the skin)
• sweet potatoes
• yams
• parsnips
• beans (black, navy, cannellini, pinto, kidney)
• chickpeas
• peas
• butternut squash
• lentils
• corn
• taro

Some examples of non-starch vegetables are:

• artichokes
• turnips
• brussels sprouts
• bean sprouts
• broccoli
• celery
• cauliflower
• eggplant
• mushrooms
• peppers
• onions
• tomatoes
• spinach
• salad greens
• asparagus

Processed granulated sugars and syrups can significantly mess with your blood sugar levels. If you have diabetes or prediabetes, simple carbs should only be enjoyed in moderation.

Some examples of simple sugars include:

• processed white bread
• packaged and non-packaged baked goods and desserts
• colorful breakfast cereal
• soda
• juices
• high fructose corn syrups (HFCSs)

Eating a potato at every meal may not be the best idea. Thankfully, there are tons of alternatives that are nutritious and just as delicious.

Craving mashed potatoes? Have puréed cauliflower instead! The creamy consistency is similar, and cauliflower is only 15 on the GI scale. You can also swap the tots for roasted brussels sprouts with fresh garlic and olive oil.

Still in the mood for finger food? Switch out fries for baked asparagus wrapped in prosciutto.

If you’re still jonesing for an actual potato, there are ways to lower its GI. Scoop out the filling and make a lighter version of potato skins, stuffed with roasted peppers and low-fat ground turkey. Or, swap your regular russet for a baked yam, sprinkled with cinnamon and nutmeg.

You want to look and feel your best. But cutting carbs out cold may not be the best solution. Keeping track of your food’s GI is a great move toward long-term dietary balance and success.

Monitor your glycemic load so you can enjoy your favorite foods while keeping your sugar levels in check. Because sometimes, you just really need a potato in your life, whether you want to “boil em, mash em, or stick em in a stew.”