Unhealthy Food Choices for People With Diabetes

Staying healthy when you have diabetes is all about making good decisions. “What should I eat?” is one of the most important ones. You probably know that carbohydrates can affect you. But so can other types of foods.

Some foods that seem harmless or even healthy can raise your blood sugar or cause inflammation. That’s dangerous if you have diabetes. On the other hand, some foods reduce inflammation and lower your risk for heart disease.

Knowing how foods affect you can help you avoid diabetes-related complications. This article reviews types of foods to avoid if you have diabetes or prediabetes. You’ll learn why these foods are harmful and what you should eat instead.

Bag of French fries
Diana Rattray

Carbohydrate Basics

To better understand why certain foods are discouraged, it's helpful to start with the basics of what makes a food an unhealthy vs. a healthy choice if you have diabetes. Let's start with carbohydrates.

If you have diabetes, you need to follow a low-carb diet. That's because too many carbs can cause blood sugar levels to spike. High blood sugar, known as hyperglycemia, causes immediate and long-term health problems when you have diabetes.

Most people with diabetes learn to count their carbs to be sure they aren’t having too many in one day. When every carb counts, you need to consider your choices carefully.

The goal should be to avoid or limit simple carbs and include mostly (if not all) complex carbs.

Avoid: Simple Carbs (Simple Sugars)

Simple carbohydrates refer to the sugary type. Refined sugars, table sugar, candy, soft drinks, and products with a lot of “added sugar” count as simple sugars.

Limit all of these. These sugars are absorbed quickly by the body, which causes a buildup of sugar in the bloodstream.

Usually, the body controls blood sugar by making insulin, a hormone that balances sugar levels. If you have type 2 diabetes, the body doesn’t use insulin correctly, which is called insulin resistance. When blood sugar levels rise, the body should produce more insulin to compensate, but in type 2 diabetes, this also does not occur. As a result, blood sugar cannot be stored for energy, causing high blood sugar levels.

Fresh fruits and vegetables fall into the simple sugars category. But they’re healthier than candy, baked treats, and processed food because they also contain fiber. Fiber slows the absorption of sugars into the blood. This prevents blood sugar from spiking.

Choose Wisely: Complex Carbohydrates (Starches)

Complex carbohydrates are often in whole grains, rice, breads, cereal, and starchy vegetables. Many of these carbs contain fiber along with vitamins and minerals, which allows them to enter the bloodstream slowly. Like fruit, they’re also less likely to significantly raise blood sugar levels.

Unfortunately, not all complex carbs are safe if you have diabetes. Some don’t have much fiber or nutrients. White bread and white potatoes, for instance, can still cause problems for blood sugar.

The Glycemic Index

Rather than just saying carbs are simple or complex, doctors give them (and all other foods) a rating. It’s called the glycemic index (GI) value. Foods are given a value from 1 to 100.

 GI Rating Category
 55 or lower Low-glycemic food
 56 to 69 Medium-glycemic food
 70 to 100 High-glycemic food

Eating low-glycemic level foods helps control type 2 diabetes.

Recap

To manage blood sugar, limit simple carbs (e.g., candy, soda) and focus on complex carbs like whole-grain breads and cereals. Though fruit contains simple carbs, their effect is tempered by its other nutritional components.

Fat Basics

There are different kinds of fats, and some of them are good for you. Saturated fat and trans fats, though, can cause problems with insulin that lead to high sugar levels.

Avoid: Saturated Fats

Saturated fats are usually found in meat, butter, milk, cheese, shortening, lard, and cream sauces. There are oils, such as coconut oil and palm oil, that are also high in saturated fat. Fried foods are typically very high in saturated fats.

A diet high in saturated fat can lead to insulin resistance. With insulin resistance, your body doesn’t use insulin correctly. That throws off your blood sugar and causes many of the complications associated with prediabetes and type 2 diabetes.

Foods that are high in saturated fat are often also high in cholesterol. This increases the risk of heart disease, particularly in people with type 2 diabetes.  

Avoid: Trans Fats

Trans fats are even worse for people with diabetes than saturated fat.

These fats are made when liquid oil is turned into a solid fat—a chemical process called hydrogenation.

Trans fats are found in foods like:

  • Shortening and stick margarine
  • Prepackaged snacks (crackers, chips, etc.)
  • Store-bought baked goods (muffins, cookies, cakes)
  • Some fast food items such as French fries

Like saturated fat, trans fat can raise blood cholesterol levels. For a heart-healthy diet, eat as little trans fat as possible.

Tips for Limiting Unhealthy Fats

  • Swap store-bought baked goods like frozen waffles with homemade or store-bought multi-grain versions. Use ingredients that have no trans fats.
  • Cook with olive oil instead of butter or stick margarine.
  • Eat freshly grilled or baked meals instead of fried fast food.
  • Read food labels carefully—each type of fat is listed separately.

Choose: "Good Fats"

Some fats can be part of a healthy diabetes diet. When choosing “good” fat, look for monounsaturated and polyunsaturated fats. These increase your cell’s sensitivity to insulin, which means the insulin can do what it’s supposed to and balance your blood sugar.

Sources of monounsaturated fats include:

  • Avocados
  • Olives
  • Nuts
  • Olive oil
  • Peanut oil
  • Canola oil
  • Safflower oil

Sources of polyunsaturated fats include:

  • Oily fish (salmon, tuna, sardines)
  • Chia seeds
  • Flaxseed
  • Sunflower seeds
  • Tofu
  • Walnuts
  • Vegetable oil

Recap

Saturated and trans fats are two fats that can increase cardiovascular health risks. This is especially problematic for those with diabetes, who are already at greater risk for these conditions. Instead, choose monounsaturated and polyunsaturated fats, which can have the opposite effect and improve blood sugar.

Frozen Foods

It’s so convenient to throw something into the oven or microwave for a few minutes, warm it up, and serve. Some of these prepared meals may even seem quite healthy. Frozen chicken, for example, doesn’t seem so bad.

When it’s heavily processed, though, even chicken is a poor choice for people with diabetes.

Food that’s been precooked and sold frozen is often filled with additives and chemicals, which can make it less nutritious. It’s also usually wrapped in breading, which gives it a higher glycemic index and increases the fat content.

Another major drawback is the sodium content. Frozen food often contains a large amount of sodium, which comes from added salt. A serving of six frozen chicken tenders (17 grams each) contains about 527 milligrams of sodium. That’s almost a quarter of the amount of sodium recommended for one day.

Sodium plays a big role in:

People with diabetes are already at risk for these problems, and too much salt increases that risk.

Healthier Alternatives

Instead of relying on these convenience meals, pick a day once a week (if possible) to prepare food. Pre-cut your vegetables, make your own soups, or prepare slow-cooker meals you bag up and have handy for when you need them. Freezing extra portions is a good solution, too.

By cooking your own meals, you can control what goes in them—including the amount of salt.

This will not only make healthy and fast meals much easier to achieve, but it will likely also give you some extra time back in your day.

Loaded Sandwiches

Sandwiches offer a perfect opportunity to have a balanced lunch. Lean proteins and vegetables, with or without whole-grain bread, make for a quick, diabetes-friendly meal.

But sandwiches can also quickly go wrong. Processed meats are one problem, as they are typically high in salt. Condiments are another concern—mayonnaise in particular.

Mayo is low in carbs, which is good. It's high in fat, but it's mostly unsaturated fat. That's also good. The high calorie content, though, makes it a poor choice for anyone who needs to watch their weight. Most people with diabetes have to be conscious of their weight, because a few extra pounds in sedentary individuals may add additional stress to the heart and lead to further insulin resistance.

Healthier Alternatives

Replace deli meat with homemade sliced turkey or chicken.

Ditch the mayo and opt for olive oil instead. Olive oil seems to lower the risk of diabetes, especially in older women.

Olive oil doesn’t have the same sticking power as mayo for tuna or egg salad. But if you use a whole-wheat wrap or pita pocket, you can enjoy great flavor and a nutritious sandwich that doesn't fall apart.

Loaded Salads

Salad bowls also sound healthy. Unfortunately, though, they can be loaded with the common enemies of people with diabetes: fat, sugar, calories, and salt.

Dressings, toppings, and cheeses, in particular, can cause these to rack up quickly.

Healthier Alternatives

To enjoy a truly healthy salad, avoid restaurant versions. Choose a fresh, homemade salad.

To make a diabetes-friendly taco salad, for example, try these changes:

  • Forget the taco shell with up to to 13 grams of carbohydrates (about 10% of the amount most adults should consume in a day). Go for a traditional salad in a bowl instead.
  • Go light on the cheese. Don’t swap full-fat for low-fat, since you might end up with more sugar. Just halve the amount in your regular recipe.
  • Swap fried meat and beans with grilled or boiled versions.
  • Replace sour cream and dressings with plain Greek yogurt.
  • Leave off any fried toppings. 
  • Add more fresh vegetables and season with chili powder.
  • Don’t leave out the avocado. This powerful fruit helps regulate insulin and reduce belly fat.
4:18

How to Make a Tortilla-Free Burrito Bowl

Sweetened Beverages

Obviously, if you’re cutting back on simple sugar, you might realize that soft drinks and non-fruit juices are bad choices. Drinking these beverages is an easy way to get too much sugar. And too much sugar causes diseases related to diabetes like:

Even seemingly healthy fruit smoothies can be a problem. Those you can buy pre-made or have whipped up at a store often have sugar added to them. Even making one at home can lead to consuming added sugar if you're not careful. For example, certain milks (e.g., vanilla almond milk) contain added sugar, unless you specifically purchase an unsweetened variety.

Healthier Alternatives

You can skip the added sugar by reading labels, watching your ingredients, and special ordering your smoothie.

But keep in mind that smoothies are still a risk for people with diabetes: Studies show that drinking carbs instead of eating solid food can cause blood sugar to rise dangerously.

The most diabetes-friendly drinks are:

  • Water with a fresh fruit twist
  • Fresh smoothies with no added sugar
  • Fresh-squeezed juices
  • Unsweetened tea and black coffee

Summary

Being mindful of what carbs and fats you consume can not only impact your blood sugar, but your risk of cardiovascular issues (which is already elevated because of diabetes).

It's also important to read labels to spot added sugars, excessive amounts of salt, and high calories as well.

As you order and shop, steer clear of things like deep-fried foods, baked goods, soda, candy, processed meats, and so on. Instead, prepare meals at home so you are fully aware of what is in them.

A Word From Verywell

Having diabetes can mean making big changes in how and what you eat. It can be overwhelming. Don’t let it discourage you from making a healthy plan, though. Your doctor can offer advice. You may also want to speak with a dietitian or get tips from a chef or food expert.

Today, there are also many new ways to get help planning meals. Some food delivery services even cater to people with diabetes. Take time to learn what you need to do to eat healthy, and you’ll see that food can continue to be pleasurable and wholesome.

18 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.
  1. Feinman RD, Pogozelski WK, Astrup A, et al. Dietary carbohydrate restriction as the first approach in diabetes management: Critical review and evidence base. Nutrition. 2015;31(1):1-13. doi: 10.1016/j.nut.2014.06.011

  2. Martín-Peláez S, Fito M, Castaner O. Mediterranean diet effects on type 2 diabetes prevention, disease progression, and related mechanisms. A reviewNutrients. 2020;12(8):2236. doi:10.3390/nu12082236

  3. National Institute of Diabetes and Digestive and Kidney Diseases. Diabetes diet, eating, & physical activity.

  4. American Diabetes Association. Get to know carbs.

  5. MedlinePlus. Type 2 diabetes.

  6. The Nemour Foundation/Kidshealth.org. Carbohydrates and Sugar.

  7. Goff HD, Repin N, Fabek H, El Khoury D, Gidley MJ. Bioactive Carbohydrates and Dietary Fibre. 2018;14:39-53. doi: 10.1016/j.bcdf.2017.07.005

  8. The Nemour Foundation/Kidshealth.org. Carbohydrates and Sugar.

  9. MedlinePlus. Glycemic index and diabetes.

  10. American Diabetes Association. Fats.

  11. Hernández EÁ, Kahl S, Seelig A, et al. Acute dietary fat intake initiates alterations in energy metabolism and insulin resistance. J Clin Invest. 2017;127(2):695-708. doi:10.1172/JCI89444

  12. American Diabetes Association. Fats.

  13. MedlinePlus. Glycemic index and diabetes.

  14. U.S. Department of Agriculture, FoodData Central. Chicken tenders or strips, breaded, from frozen.

  15. The Centeres for Disease Control and Prevention. Sodium.

  16. Song Y, Li Y, Guo C, et al. Cross-sectional comparisons of sodium content in processed meat and fish products among five countries: potential for feasible targets and reformulation. BMJ Open. 2021;11(10):e046412. doi: 10.1136/bmjopen-2020-046412

  17. Guasch-Ferré M, Hruby A, Salas-Salvadó J, et al. Olive oil consumption and risk of type 2 diabetes in US women. Am J Clin Nutr. 2015;102(2):479-486. doi:10.3945/ajcn.115.112029

  18. Bondonno NP, Davey RJ, Murray K, et al. Associations between fruit intake and risk of diabetes in the AusDiab cohort. J Clin Endocrinol Metab. 2021;106(10):e4097-e4108. doi:10.1210/clinem/dgab335

By Stacey Hugues
Stacey Hugues, RD is a registered dietitian and nutrition coach who works as a neonatal dietitian at Beth Israel Deaconess Medical Center in Boston.