Eating More Plants May Prevent Diabetes

Easy Ways to Incorporate More Plants into Your Diet

Research shows that a plant-based diet can reduce the risk of type 2 diabetes. Prediabetes is a precursor to type 2 diabetes. According to the Center for Disease Control, approximately 88 million American adults—more than 1 in 3—have prediabetes, and more than 84% don’t know they have it.

What comes to mind when someone tells you that you should eat more plants? Do you envision boring, drab green, boiled broccoli or munching on sticks and twigs? Put these visuals behind you; properly cooked plant-based foods add beautiful color, texture, flavor, volume, and a wealth of nutritious compounds to your eating experience.

Don't worry if you don't feel comfortable or savvy in the kitchen. There are simple ways to include more plants into your diet and simple preparation techniques that can help you do so.

Beautiful bowl of plant based foods
jenifoto/iStock/Getty Images Plus.

What Research Says

Higher intake of vegetables, whole-grain foods, legumes, and nuts have been associated with a substantially lower risk of insulin resistance, type 2 diabetes, and improved glycemic control.

In one study, researchers calculated that every 66 gram (gm) increase in total daily fruit and vegetable intake was associated with a 25% lower risk of developing type 2 diabetes. This is equal to eating about 1/2 cup of chopped vegetables or 1 small-to-medium sized piece of fruit.

Root vegetables, green leafy vegetables, and apples, specifically have also been associated with lower diabetes risk. Other studies have shown that a diet rich in whole grains, legumes, and nuts has been associated with lower diabetes risk.

One of the commonalities in all of these food groups is that they are full of fiber. Fiber contains a unique blend of starches, vitamins, minerals, phytochemicals, and antioxidants. Fiber is an indigestible carbohydrate that has many roles, including keeping bowels regular, aiding in satiety, helping to pull cholesterol away from the heart, and regulating blood sugar.

What Exactly Does Eating More Plants Mean?

A meal plan that is rich in plant-based foods maximizes the intake of fruits, vegetables, whole grains, nuts, seeds, and legumes (beans), while also limiting animal-based foods that tend to promote insulin resistance such as processed meat and red meat. In addition, other types of foods that you should limit include sweets and refined grains like white bread and pasta.

How to Get Started

If you are not accustomed to eating lots of fibrous foods, such as fruits and vegetables, you should aim to start slowly. In addition to being overwhelmed, adding too much fiber to your diet too quickly can result in gas, bloating, and abdominal discomfort.

As you increase your fiber intake, increase your water consumption at the same time. Doing so will help keep your bowels regular. Aim to change one meal at a time with the goal of eating one fruit or vegetable at each meal.

Some simple tips for adding more plants to your diet include:

  • Aim to eat one serving of fruits or vegetables at most meals and snacks. One serving is about one small piece of fruit or one cup of raw vegetables or 1/2 cup cooked vegetables.
  • Add raw vegetables to wraps, sandwiches, and pitas for extra volume, fiber, and crunch.
  • Visualize your plate. Make your plate half vegetables and one-quarter a whole grain or starchy vegetable, such as sweet potatoes, and one-quarter lean protein like white meat chicken, turkey, fish, or tofu.
  • Add one serving (1/4 cup) of unsalted nuts to your day. Add them to your morning oats, include them in a salad, or snack on them with a piece of fruit.
  • Aim to make half of your grain intake whole grains. Whole grains include whole grain bread, barley, bulgur, corn, farro, freekeh, oats, wheat, wheatberries, quinoa, rye, etc.
  • Consider adopting a meatless day, once a week. Use legumes as a protein and carbohydrate source. Serve up a vegetable-based chili, or make some homemade hummus to eat with whole grain chips or fresh crudite.

Preserving Color and Flavor

Many people do not eat the recommended amount of fruits and vegetables daily, oftentimes because they aren't comfortable preparing them. The most appealing and appetizing vegetables are those that are bright in color and are not too soft and not too hard.

Overcooking vegetables can result in leaching of vitamins as well as diminished flavor and color. No one is going to be excited to consume vegetables that are mushy and ugly.

If you are not eating your vegetables raw, properly cooking them will make your vegetables delicious, nutritious, and beautiful to look at. There are many different ways to prepare vegetables.

Some techniques to preserve color and flavor include:

When using a moist heat cooking method, such as simmering, season water with 1 teaspoon of salt per liter of water. Salt seasons the vegetables and enhance their natural flavor. The water should not be super salty or bland. Adding a bit of olive oil in the water will coat the vegetables and give them a nice shine.

Add acid such as vinegar or lemon to white vegetables to preserve their color. Cauliflower cooked with an acid will be whiter than those that are not cooked with an acid. Do not add acid when cooking green vegetables because this will turn them dull, olive green.

Orange and yellow pigment vegetables can be cooked with a lid on or off and with or without an acid. If you do use an acid, add it halfway through the cooking process.

Red and white vegetables contain flavonoid pigments, therefore an acid will preserve their color. For example, adding red wine vinegar while cooking beets will help restore their color.

Green vegetables contain chlorophyll and are very sensitive to heat and acids. Prolonged cooking of green vegetables will result in vitamin and color loss. Do not cover green vegetables with a lid as this will allow the natural acids to escape. Cook them with the lid off.

Whatever cooking method you choose, check for doneness periodically. Simply taste them, they should offer little resistance to the tooth. Green vegetables can go from perfectly cooked to overly cooked in a matter of minutes so keeping an eye on them is important.

Don't forget to season. If you are using a moist heat cooking method such as simmering, after draining, season to taste and finish with herbs, vinaigrettes, or butter. If you are finishing green vegetables with a vinaigrette or sauce, do so right before you serve them to preserve their color.

Adding a small amount of fat to vegetables will help you to absorb their fat-soluble vitamins. Vitamins A, D, E, and K are fat-soluble that need to be eaten with fat so they can be absorbed.

Common Cooking Methods

Knowing different ways to cook vegetables can help you build your experience and repertoire.


Steaming is a fat-free, gentle, moist heat cooking method. Although it is one of the healthiest ways to cook vegetables, it is often neglected in cooking because it is associated with bland food. But it doesn't have to be.

Steaming preserves vitamins and minerals because the vitamins do not get leached into the water. This simple and quick cooking method can be used for almost any vegetable.

To steam properly, all you need is a pot (or deep pan), a perforated rack or container to hold the food above the water, some simmering water, and a tight-fitting lid to prevent the steam from escaping. Fill your pot with enough water (at least an inch), but not too much where it is touching the colander, rack, or steamer basket.

Once the water begins to simmer (for delicate foods) or boil (for firmer foods), add your vegetables to the colander or basket and place the basket in the pot, sprinkle with some salt (to bring out the natural flavor), and place the lid on top.

The steam vapor will cook the vegetables. Different vegetables will need different cooking times. Keep an eye on the liquid to assure it hasn't all evaporated. Pierce the vegetables with a fork and taste for doneness. They should be tender, but not too soft or hard.

After your vegetables are steamed to doneness, shake off the excess moisture, place them in a bowl, add a bit of fat such as olive oil, and season with fresh herbs, spices, or anything else you'd like. Then toss, and re-season.

You can also use steaming to re-heat foods, such as vegetables and whole grains. Steaming adds moisture to foods and is a clean way to prepare food. It may be your new favorite easy and simple cooking method.

Submersion Cooking Methods

These types of cooking methods use liquid, such as hot water to cook the vegetables. The difference in the techniques is how hot the water is and how long the vegetables cook. The type of vegetable you are using will determine your cooking method.

The vegetables will be placed directly in the hot liquid. This is still a healthy cooking method, but keep in mind that it is not recommended to boil vegetables for extended periods of time as this will lead to vitamin loss and will yield an unpleasant looking end product.


Blanching vegetables requires cooking them partially in boiling water for a short period of time, followed by an ice bath (shocking) to stop the cooking process. Blanching vegetables can be done in advance to preserve vitamins, minerals, and flavor. Blanched vegetables can be used as crudité or they can be made in advance and later steamed or quickly sautéed.

To blanch, bring a pot of water to a boil, season with salt, and add the vegetables. Cook for about 30 seconds to 1 minute and then transfer the drained vegetables to an ice bath.

Shock in an ice bath to stop the cooking process and preserve their color. Remove from the water once they are fully cooled so that they do not become waterlogged. Use them for crudité and serve with hummus and guacamole or pack as a snack. You can also plan on cooking them later.


Using the same procedure as blanching, the term parboiled is often used interchangeably, but these techniques are a little different. When parboiled, vegetables are cooked a little longer than when they are blanched. They are a bit softer and can also be sautéed or steamed to finish.


When simmering plant-based foods, food is submerged in a liquid that is not fully boiling. It is the most common moist heat cooking method and is ideal for dishes that require longer cooking times such as soups and stocks.

You can simmer vegetables in a flavorful liquid, such as broth, to add flavor or simmer them in salted water and submerge them in an ice-bath and then finish them with your desired flavors.


Sautéing is typically a quick, dry heat cooking method. All you need is some fat, such as oil, a hot pan, and vegetables. Before cooking, you need to heat the pan (using medium-to medium-high heat) and add enough oil to coat the surface of the pan.

Cut the food into bite-sized pieces to ensure even cooking. Use an oil with a higher smoke point, such as canola oil, and intend on using an appropriately sized pan for the amount of food you are cooking. Overcrowding the pan will prevent the food from cooking evenly.

Cook over high heat until cooked through, you should hear a good sizzle. If you have vegetables pre-cooked, such as blanched and parboiled, you can sauté them to finish them off. When sautéing vegetables that have a higher water content, such as, zucchini and eggplant, season them with salt and pepper at the end of cooking to prevent moisture loss.

You can keep it simple, using, salt and pepper, or spice it up and add fresh or dried herbs and spices towards the end of cooking. If you are sautéing harder raw vegetables that take longer to cook, such as potatoes, steam them for a few minutes first in the pan with 1/4 cup of water and then sauté.

Or begin the sauté process and once the potatoes start to develop a golden crust, toss them periodically and turn the heat down until the potatoes to cook through. Once they are done cooking, season to taste and serve.


Grilling is a great way to add flavor and color and spice to your vegetables. The most commonly grilled vegetables include eggplant, onions, squash, and peppers, though you can grill most vegetables. Get creative and opt to grill salad, artichokes, beets, or any of your other favorites. You can use the barbecue or the grill pan.

And don't worry about them being carcinogenic, either. The American Institute of Cancer Research says that polycyclic aromatic hydrocarbons (PAHs) present in grill flames and heterocyclic amines (HCAs) which have been associated with grilling meats and increased risk of cancer, are not formed when grilling fruits and vegetables. But it would not be recommended to char the vegetables. You should avoid eating any charred black sections.


This is a simple and delicious way of making vegetables. Roasting vegetables lends to the beautiful caramelization which tastes amazingly sweet. Roasting involves seasoning vegetables with desired flavors and cooking at high heat, around 400-475 degrees Fahrenheit until the desired doneness.

The smaller the vegetable, the higher the oven needs to be to create a crispy, golden exterior. You can roast any vegetable, but vegetables with less water content, such as root vegetables, are great for roasting. These are better cooked at lower temperatures, around 350-400 degrees Fahrenheit. Many other vegetables such as cauliflower, broccoli, Brussels sprouts, and green beans are also great roasted.

Cut your roasted vegetables into even size pieces. Prior to roasting, vegetables need to be coated with fat, such as oil. Next, season them with salt to bring out their natural flavor, you can also season with pepper or other spices. Rosemary or thyme will add earthy notes, or vinegar will add bitter notes.

Shallow, heavy-duty sheet pans are good for roasting. You can oil the pan or line it with parchment to prevent sticking. Place vegetables on the pan in a single layer to avoid overcrowding. Harder vegetables may need to be turned halfway through the cooking process.

Slow roasting (around 200 degrees Fahrenheit) allows for moisture to slowly evaporate and is good for vegetables such as tomatoes. To determine doneness, the knife should slide in and out or you can judge them based on how you like them cooked. If needed, a touch of oil will add sheen or you can also add toasted nuts and seeds or fresh herbs.

Cooking with Frozen Vegetables

Frozen vegetables are packaged at the peak of ripeness, which means that they generally contain more vitamins and minerals. Cooking frozen vegetables is the same as fresh. You can use submersion cooking methods, such as adding them to boiling water and gentle boiling.

Once they are done, season to taste as desired. You can also roast or sauté frozen vegetables for added flavor. Depending on the variety, they will typically cook quicker than fresh.

A Word From Verywell

Most of us would benefit from eating more plants. For those people at risk for diabetes, simply adding fruits, vegetables, and whole grains can potentially decrease the risk of diabetes.

Creating a meal plan that includes more plants, such as fruits, vegetables, whole grains, legumes, nuts, and seeds, may seem overwhelming, but making one change at a time can yield big results. Understanding some simple preparation methods, as well as ways to keep vegetables looking beautiful and tasty, may add some appeal to eating more of them.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Center for Disease Control. Prediabetes—your chance to prevent type 2 diabetes.

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  4. Zheng J, Sharp S, Imamura F, et al. Association of plasma biomarkers of fruit and vegetable intake with incident type 2 diabetes: EPIC-InterAct case-cohort study in eight European countriesBMJ. 2020 Jul 8;370:m2194. doi:10.1136/bmj.m2194

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  6. The American Institute of Cancer Research. Five steps for cancer safe grilling.

By Barbie Cervoni MS, RD, CDCES, CDN
Barbie Cervoni MS, RD, CDCES, CDN, is a registered dietitian and certified diabetes care and education specialist.