Starchy Vegetables: Benefits and Moderation

Starchy vegetables—potatoes, peas, and butternut squash, to name a few—offer important nutritional value and are great sources of vitamin C, B vitamins, and potassium. But they also have a higher proportion of carbohydrates per unit weight than other vegetables, which can raise blood sugar.

Given both their pros and cons, moderation of starchy vegetables—rather than elimination—is key. This is a particular concern if you have diabetes, as you need to monitor your blood glucose carefully. Research has also shown that lowering your carb intake can reduce the risk of obesity, irrespective of whether or not you have diabetes.

In this article, you’ll learn which vegetables are starchy and non-starchy, how to monitor your consumption, and how to prepare starchy options in healthier ways.

Which Vegetables Are Starchy?

There is no clear-cut definition of what “starchy” means in terms of vegetables. Some authorities suggest that vegetables that contain greater than 10% carbs by weight are starchy. Others define it as having 15 grams or more of carbohydrates per one cup of raw food or 1/2 cup of cooked food.

In the end, many regard foods as starchy if they have a powdery texture when cooked or produce a starch-like residue when soaked. Examples include corn and cornstarch, potatoes and potato starch, and peas and pea starch. The less starchy a vegetable is, the less likely it will have these qualities.

Given these general parameters, here are some examples of starchy and non-starchy vegetables:

How Do Starchy Vegetables Affect Blood Sugar?

There is a somewhat straightforward association between the amount of carbs you eat and their impact on your blood sugar. This is because whenever you eat food, your body deploys digestive enzymes to break down carbs into the body’s main source of energy, called glucose. The more carbs you eat, the more glucose is released into the blood.

The impact that different foods have on blood glucose is classified by their glycemic index (GI). The higher the GI value—ranging from 0 to 100—the higher and faster blood glucose levels will rise.

• Low-GI foods have a GI value between 1 and 55.
• Moderate GI foods have a GI value between 56 and 69.
• High-GI foods have a GI value of 70 or greater.

What Amount of Starchy Vegetables Should You Eat?

If you have diabetes or are on a low-carb weight loss plan, watching your intake of starchy foods is important. By doing so, you can reap the nutritional benefits of foods like squash, peas, sweet potatoes, and corn without causing undue spikes in blood sugar.

While you can keep track of your carbs by downloading apps that count the carbs for you, a simpler solution may be the so-called “plate method.”

Using the plate method, each meal would be divided into the following portions:

• 1/2 non-starchy vegetables
• 1/4 carbohydrate foods such as starchy vegetables, whole grains, and beans
• 1/4 lean proteins

The portion sizes can vary. Starchier/high-GI vegetables have smaller 1/2-cup servings, while less starchy/moderate-GI foods have larger one-cup portions.

How Does Cooking Affect Starchy Vegetables?

The way you cook starchy vegetables can make a big difference in how healthy they are and how much they impact your blood sugar.

Take the potato, for example. From a nutritional standpoint, eating boiling potatoes is clearly healthier than eating French fries, the latter of which is high in calories and saturated fat. But there is also evidence that GI values can be changed by the manner in which a potato is cooked.

According to a 2020 study in LWT Food Science and Technology, 46% of starches are released when potatoes are boiled, while 64% are released when they are microwaved. By comparison, only 2% are released when a potato is fried or deep-fried.

The same seems to apply to other starchy vegetables as well.

So instead of frying or deep-frying vegetables, choose healthier preparations such as baking, steaming, boiling, and microwaving. You can also broil and grill vegetables, but limit the amount of oil you use and try to use healthy ones like extra virgin olive oil.

Summary

Starchy vegetables have more carbohydrates by weight and raise your blood sugar more than non-starchy vegetables. This makes them a potential concern for people with diabetes or those on a low-carb weight loss plan.

You should still eat starchy vegetables for their nutritional value, but try to limit your portion to 1/4 of your meal plate. Baking, boiling, steaming, or microwaving starchy vegetables may reduce their starch content, while frying or deep frying them generally will not.

A Word From Verywell

Starchy vegetables aren’t something you should be afraid of. They are not “unhealthy,” although they may affect your blood sugar or undermine your weight loss plan if you eat too much. But you can say the same about a lot of other foods, including fruits and dairy.

Moreover, unlike most processed and refined foods, starchy vegetables have significant nutritional value.

So don’t go out of your way to cut out starchy vegetables. Instead, speak with your healthcare provider or a certified dietitian about ways to incorporate the right amount into your diet if you have diabetes or are embarking on a weight loss plan.