Type 1 diabetes diet definition and facts
- In Type 1 diabetes the pancreas can do
longer release insulin. The high blood sugar that results can lead to
complications such as kidney, nerve, and eye damage, and cardiovascular disease.
- Glycemic index and glycemic load are
scientific terms used to measure he impact of a food on blood sugar. Foods with
low glycemic load (index) raise blood sugar modestly, and thus are better choices
for people with diabetes.
- Meal timing is very important for
people with type 1 diabetes. Meals must match insulin doses. Eating meals with a
low glycemic load (index) makes meal timing easier. Low glycemic load meals
raise blood sugar slowly and steadily, leaving plenty of time for the body (or
the injected insulin dose) to respond. Skipping a meal or eating late puts a
person at risk for low blood sugar (hypoglycemia).
- Foods to eat for a type 1 diabetic diet
include complex carbohydrates such as
- brown rice,
- whole wheat,
- beans, and
- Foods to avoid for a type 1 diabetes diet include
- sodas (both diet and regular),
- simple carbohydrates - processed/refined sugars (white
bread, pastries, chips, cookies, pastas),
- trans fats (anything with the word
hydrogenated on the label), and high-fat animal products.
- Fats don't have much of a direct effect
on blood sugar but they can be useful in slowing the absorption of
- Protein provides steady energy with
little effect on blood sugar. It keeps blood sugar stable, and can help with
sugar cravings and feeling full after eating. Protein-packed foods to include on
your menu are beans, legumes, eggs, seafood, dairy, peas, tofu, and lean meats
- Five type 1 diabetes "superfoods" to
eat include fiber, sardines, vinegar, cinnamon, and berries.
- The Mediterranean diet plan is often
recommended for people with type 1 diabetes because it is full of nutrient-dense
foods, including lots of fresh vegetables, some fruit, plant-fats such as olive
oil and nuts, fish such as sardines, and occasional meat and dairy.
- When dining out, ask questions about
what a dish contains or how it's prepared, review menus online before you go,
and let your friends and family know your dietary restrictions beforehand.
What is type 1 diabetes?
In Type 1 diabetes the pancreas can do longer release insulin. This is important because insulin is needed to move sugar (glucose) out of the blood and into muscle, brain, and other target cells where it is used for energy. The high blood sugar that results can lead to a number of complications such as kidney, nerve, and eye damage, as well as cardiovascular disease. Moreover, cells are not receiving the glucose they need for healthy functioning. The loss of insulin secretion is typically caused by auto-immune destruction of the insulin-producing islet beta cells in the pancreas. Because people with type 1 diabetes can no longer produce their own insulin, they must inject insulin. Keeping blood sugar steady, by matching carbohydrate intake with the appropriate insulin dose, can prevent long-term complications of type 1 diabetes. Type 1 diabetes cannot be cured, but it may be managed.
Early Type 1 Diabetes Symptoms
Early symptoms of any type of diabetes are related to high blood and urine glucose levels and include:
- Increased urination, and
- Increased thirst
- Weight loss or gain
- Vaginal infections in women and yeast infections in both men and women
Why are following the guidelines of a type 1 diabetes diet plan important?
While there are no absolute diet restrictions in type 1 diabetes, healthier food choices can make control a lot easier. For example, meal timing is very important for people with type 1 diabetes. Meals must match insulin doses.
Most people with type 1 diabetes use a long-acting insulin (also called basal insulin or NPH), which means it will continue to lower blood sugar over 24 hours. This means it will lower blood sugar even if there is no glucose from dietary carbohydrates to act upon. Because of this, skipping a meal or eating late puts a person at risk for low blood sugar (hypoglycemia).
On the other hand, eating a larger meal or a meal that contains more carbohydrates that normal will raise blood sugar more than the basal insulin can dispose of. In this situation, a short-acting insulin (also called regular insulin) must be given in the appropriate dose to match the carbohydrate content of the meal and the level of blood glucose before eating.
Eating meals with a low glycemic load (index) makes meal timing easier. Low glycemic load meals raise blood sugar slowly and steadily, leaving plenty of time for the body (or the injected insulin dose) to respond.
People who use continuous glucose monitoring and insulin pumps instead of finger sticks and injecting insulin have a little more flexibility in their meal timing because they have real-time feedback to help them match carbohydrate intake with insulin. However, everyone benefits from becoming more aware of their dietary intake, making diet restrictions to stay consistent with a low glycemic load diet, and matching their meals with appropriate insulin doses.
Paying attention to meal timing and glycemic load enables people with type 1 diabetes to keep their blood glucose levels relatively stable. Stable blood sugar prevents the complications of hypoglycemia and hyperglycemia1. Recent studies have provided contradictory data regarding the benefit of better glycemic control in preventing cardiovascular disease. While we used to think hyperglycemia was worse, the data show increased risk of cardiovascular disease when hypoglycemia is common2. Research tells us that maintaining an overall stable blood sugar (few highs or lows) is best for preventing complications of any kind. Low glycemic load eating and consistent meal timing are the best ways to achieve this.
While some people go overboard with diet restriction, it is also important to consider the nutritional balance (fat, protein, and carbohydrates) in a meal. Specifically, fat, protein, and fiber all slow down the absorption of carbohydrates, and thus allow time for insulin to work, gradually moving glucose out of the blood and into the target tissues. Slower digestion and absorption maintains a more stable blood sugar level.
What are glycemic load and glycemic index?
Glycemic index and glycemic load are scientific terms used to measure the impact of a food on blood sugar.
Foods with low glycemic load (index) raise blood sugar modestly and thus are better choices for people with diabetes. The main factors that determine a food's (or meal's) glycemic load is the amount of fiber, fat, and protein it contains.
The difference between glycemic index and glycemic load is that glycemic index is a standardized measurement per fixed amount of the food, and glycemic load accounts for a real-life portion size. For example, the glycemic index of a bowl of peas is 68 but its glycemic load is 16 (lower is better)3. If you just referred to the glycemic index, you'd think peas were a bad choice, but in reality, you wouldn't eat 100 grams of peas. With a normal portion size, peas have a healthy glycemic load as well as being an excellent source of protein.
One way to pay attention to glycemic load is similar to carb counting. For example, if you are about to eat a cup of whole wheat pasta with 35 grams of carbs and it also has 5 grams of fiber; you can subtract the 5 grams of fiber from the total carbohydrate because the fiber is reducing the glycemic load of the pasta. Thus, a rapid-acting insulin dose should be given to cover 30 grams of carbohydrate. You also can learn to follow a low glycemic load diet by looking at lists of dietary restrictions, or understanding how to add fat, fiber, or protein to a meal.
What carbohydrates, fats, and proteins are recommended for a type 1 diabetes diet?
Carbohydrates for a type 1 diabetes diet menu
Carbohydrates are the primary food category that raises blood sugar. Carbohydrates can be classified as simple sugars or complex carbohydrates. Most people think about breads, pastas, sweets, and baked goods when they think about carbs. Fruits and vegetables also contain carbohydrates, but the high amounts of fiber and nutrition make them good options despite the carbs.
Complex carbohydrates are in their whole food form and include additional nutrients such as fiber, vitamins, and smaller amounts of proteins and fats. These additional nutrients slow down the absorption of the glucose and keep blood sugar more stable. Examples of complex carbohydrates are
- brown rice,
- whole wheat,
- steel-cut oatmeal,
- beans, and
Simple carbohydrates are easily recognized as "white foods," for example,
- white bread,
- pastries, and
- white potatoes.
Simple carbohydrates contain few other nutrients to slow down sugar absorption and thus these foods raise blood sugar dangerously fast. A type 1 diabetes diet restricts simple carbohydrates in favor of healthier options.
Fats for a type 1 diabetes diet menu
- Fats have little direct effect on blood sugar; however, as part of a meal, they are useful in slowing down the absorption of carbohydrate.
- Fats also have effects on health that are not related to blood sugar. For example, animal-meat fats increase the risk of cardiovascular disease. However, dairy, and specifically fermented dairy such as yogurt appear to decrease this risk4.
- Plant-based fats such as olive oil, nuts, seeds, and avocado are associated with lower disease risk5.
- Fat also contributes to feelings of satiety and can play a role in managing overeating and carbohydrate cravings.
Protein for a type 1 diabetes diet menu
Protein provides slow steady
energy with relatively little effect on blood sugar. Protein also provides the
body with steady energy and helps it body heal and repair.
The healthiest proteins for a type 1 diabetes diet come from plant sources such as
- nuts and nut butters,
- peas, and
- soy foods.
Lean animal sources of protein also can be consumed a few times per week. These include
- turkey, and
Other good protein choices include
- fish and seafood,
- organic dairy products,
- tofu and soy foods, and
- lean meats such as chicken and turkey.
Protein should always be part of a meal or snack. Protein not only keeps blood sugar stable, but it also helps with sugar cravings and feeling satisfied.6 Protein can come from both animal or plant sources, however, animal proteins are often sources of unhealthy saturated fat.
Proteins to avoid include those that increase inflammation and cardiovascular risks
- red meats, and
- ultra-pasteurized, non-organic milk, cheese, and other dairy products.13
What grains and starches are recommended for a type 1 diabetes diet plan?
Grains and starchy vegetables
Whole grains, such as brown rice, quinoa, and oatmeal are good sources of fiber and nutrients and have a low glycemic load. This makes them good choices. Processed food labels make it very confusing to understand whole grains. For example "whole wheat bread" is made in many different ways and some of it is not really that different from white bread in its blood sugar impact (glycemic load). The same is true for whole grain pasta - it's still pasta. Whole grains will require less insulin because of their low glycemic load. The best way to understand them is to check the nutrition label. Find the grams of dietary fiber and subtract that from the total carbohydrate. That number should be less than 25 per serving. Starchy vegetables such as potatoes, squash, corn, and other root vegetables are higher in carbohydrates than green vegetables but lower than refined grains. They also are good sources of nutrients such as vitamin C. They are best eaten in smaller portions (1 cup) with an additional dose of insulin to cover 1 serving of carbohydrate.
Non-starchy vegetables, such as green leafy vegetables, can be eaten in abundance. These foods have limited impact on blood sugar and also have many health benefits, so eat up! Almost everyone can eat more vegetables - we need at least 5 servings a day. Fresh vegetables are a great option, and usually the tastiest option. However, studies show that frozen veggies have just as many vitamins and nutrients because they are often frozen within hours of harvesting. Just check to make sure there aren't added fats or sweeteners in the sauces that are on some frozen veggies. If you don't like vegetables on their own, try preparing them with fresh or dried herbs, olive oil, or a vinaigrette dressing. Even adding a small amount of butter to your veggies is better than not eating them at all. Aim to consume vegetables in a rainbow of colors. This is a good way to get all of your nutrients.
What foods should be avoided if you have type 1 diabetes?
People with type 1 diabetes should avoid many of the same unhealthy foods that everyone should limit. In short, this means restricting processed foods and food with a high glycemic load. This includes
- sodas (both diet and regular),
- processed/refined sugars (white bread, pastries, chips, cookies, pastas),
- trans fats (anything with the word hydrogenated on the label), and
- high-fat animal products.
Restrict “white foods” i.e. pasta, bread, scones, cookies, flour, sugar, white potato, etc. This is an easy way to remove high glycemic load foods. It is important to remember that, unlike type 2 diabetes, food choices didn't specifically contribute to developing type 1 diabetes but they do impact how someone manages diabetes. People with type 1 and 2 diabetes alike are at risk for the complications that stem from high blood sugar, such as cardiovascular disease and obesity. Because of this, attention to healthy eating is important and foods that increase the risk of cardiovascular disease should be avoided.
What diets are recommended for a type 1 diabetes eating plan?
Foods to include in a meal plan
- Insulin-matched whole-grain carbohydrates
- Mediterranean-diet foods
- Nutrient dense, highly colorful foods
- Low glycemic load diet plans
People with type 1 diabetes should follow the same healthy meal plans as all other people interested in preventing chronic disease, However, they must be more aware of the carbohydrate content of their meals so they can match their insulin dose appropriately. In order to do so, there are a few rules of thumb that can be followed.
- In general, one unit of insulin covers 15 grams of carbohydrate. This is equivalent to 1/2 c of whole grains, 1 c of starchy veggies (such as squash or sweet potato), or even less of a refined (white) carbohydrate. This is a generality, and each person with type 1 diabetes needs to know his or her personal insulin-to-carbohydrate ratio. The ratio changes depending on the duration of diabetes, level of physical activity, and body weight. Insulin dosing also needs to be adjusted to take into account the blood glucose level before the meal. If blood sugar is above the target level, for example above 120, additional units of insulin are added to further bring it down. Generally, one additional unit will reduce blood sugar by about 50 points, but again, this varies for each individual.
- A healthy meal plan should include good quality protein, healthy fats, and smaller amounts of complex carbohydrates. While many public health guidelines recommend 45%-65% carbohydrate, research (including my own) demonstrates that dietary restriction of carbs allows people with diabetes to use less insulin, have more stable blood sugar, and feel better7,8.
- When carbohydrates are consumed, they should be low glycemic load.
- When fats and proteins are consumed, they should primarily come from plant sources.
- This dietary pattern can be most easily incorporated by following a Mediterranean diet plan. This refers to the true Mediterranean pattern traditionally followed in the south of Italy and Greece; not "Americanized Italian," which is heavy in pasta and bread. The Mediterranean pattern includes lots of
- fresh vegetables,
- some fruit,
- plant-fats such as olive oil and nuts,
- fish such as sardines, and
- occasional meat and dairy.
This type 1 diabetes diet plan is full of very nutrient-dense foods, meaning you get a lot of vitamins, minerals and other healthful properties for every calorie consumed.
What tips can be used when eating out with type 1 diabetes?
It can be challenging to dine out, both because of the unknowns about what exactly a meal will contain in terms of carbs and calories, but also because eating out with friends or family can often lead to unintentional pressure to eat foods we would be better off without, such as dessert! When people with type 1 diabetes eat out, it is important to check blood sugar before the meal and 2 hours after so that post-prandial insulin adjustments can be made if blood sugar levels aren't ideal.
- When eating out, don't feel shy about asking questions about what a dish contains or how it is prepared.
- Look at menus online before you go.
- Talk to your friends and family beforehand about your dietary restrictions and preferences for a healthy meal.
- Tell them it's important to your long-term health that you stay on your healthy eating plan and ask them not to encourage you to eat things that aren't good for you.
- Friends and family are often just trying to demonstrate their love by wanting you to enjoy a dessert, however mistaken that is. Open communication can help them understand that they can best help you by not making it more difficult to stay on track. Then they can feel they are truly demonstrating their love by looking after your long-term wellbeing.
5 Diabetes superfoods
Superfoods are foods that benefit your health beyond providing calories or fats, protein, or carbohydrates. Superfoods may be particularly rich in types of vitamins or other nutrients that are uniquely beneficial for people with type 1 diabetes. Superfoods are the opposite of diet restrictions - you can eat superfoods abundantly.
1. Fiber is a superfood because it brings down the glycemic load of any meal, increases a feeling of fullness (satiety), and stabilizes bloods sugar. A recent study demonstrated that fiber not only helps reduce cardiovascular risk among people with type 1 diabetes, it also reduces inflammation.9 Furthermore, oat fiber is beneficial in lowering LDL cholesterol. Good sources of soluble fiber include
- flax and chia seed,
- apples and pears,
- lentils, and
2. Sardines are a type 1 diabetes superfood because sardines are a great source of anti-inflammatory omega 3 fatty acids. Sardines are also low on the food chain, not at risk for overfishing or habitat destruction, and are unlikely to be heavily contaminated with mercury or PCBs. Enjoy them fresh with marinara or canned in monounsaturated olive oil on crackers.
3. Vinegar is best consumed as vinaigrette dressing on your salad, but it has beneficial effects no matter how you enjoy it. Vinegar, or acetic acid, slows gastric emptying, which has several beneficial effects for people with type 1 diabetes. This slows the glucose release into the blood stream, thereby allowing for a small, steady insulin response instead of a large insulin surge. Vinegar also increases satiety, so if you enjoy salad with vinaigrette as your first course, you are less likely to overeat during the main course.
4. Cinnamon has been proven to lower blood glucose in humans, including people with type 1 diabetes.10 Cinnamon lowers both fasting and after meals (postprandial) glucose. It has been studied in a number of trials and systematic reviews.11 Cinnamon also is high in polyphenols which help prevent complications of diabetes.12
5. Berries are a surprise diabetes superfood. Even though they are sweet-tasting, berries have a well-balanced glycemic load of fiber to fructose. This means the benefits outweigh the harms of the added fructose and sugars. The dark pigments that give berries their color are high in polyphenols which have high antioxidant activity. The more colorful the foods we eat, the more polyphenols we get.
What about drinking alcohol and type 1 diabetes?
For most people with type 1 diabetes, the same guidelines for moderate alcohol consumption apply as they do to everyone. Research shows that one alcoholic drink per day for women and two a day for men reduces cardiovascular risk, and doesn't have a negative impact on diabetes. However, alcohol can lower blood sugar so it is important to be aware of hypoglycemia and to check blood sugar levels before having an alcoholic drink. Having food with your alcoholic drink will help minimize the risk for hypoglycemia. It is also important to know that hypoglycemia symptoms often mimic those of intoxication. It is a good idea to wear a diabetes alert bracelet so that people know to offer food if you demonstrate hypoglycemic symptoms. It is also important to remember that mixed alcoholic drinks and cocktails (i.e. margaritas) are often made with sweeteners that contain lots of carbohydrate. These drinks will increase blood sugar.
1. HOMA Calculator. University of Oxford.
2. Glycemic Load Index. lowglycemicload.com
3. Ericson U., et al. "Food sources of fat may clarify the inconsistent role of dietary fat intake for incidence of type 2 diabetes." Am J Clin Nutr. 2015 Apr 1.
4. Trapp, C,. et al. "Preparing to prescribe plant-based diets for diabetes prevention and treatment." Diabetes Spectrum February 2012 vol. 25 no. 1 38-44.
5. Chungchunlam SM., et al. "Dietary whey protein influences plasma satiety-related hormones and plasma amino acids in normal-weight adult women." Eur J Clin Nutr. 2015 Feb;69(2):179-86.
6. Alison B. Everet, et al. "Nutrition Therapy Recommendations for the Management of Adults with Diabetes. Diabetes Care Journal. January 2014 vol. 37 no. Supplement 1 S120-S143
7. Lasa A., et al. "Comparative effect of two Mediterranean diets versus a low-fat diet on glycaemic control in individuals with type 2 diabetes." Eur J Clin Nutr. 2014 Jul;68(7):767-72.
8. Klonoff DC. "The beneficial effects of a Paleolithic diet on type 2 diabetes and other risk factors for cardiovascular disease."
J Diabetes Sci Technol. 2009 Nov 1;3(6):1229-32.
9. Jönsson T., et al. "Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study." Cardiovasc Diabetol. 2009 Jul 16;8:35.
10. Kodama S. et al. "Influence of fat and carbohydrate proportions on the metabolic profile in patients with type 2 diabetes: a meta-analysis." Diabetes Care. 2009 May;32(5):959-65.
11. Oberg EB, Bradley RD, Allen J, McCrory MA. "CAM: naturopathic dietary interventions for patients with type 2 diabetes."
Complement Ther Clin Pract. 2011 Aug;17(3):157-61.
12. Yokoyama, Y. et al. "Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysis." Cardiovascular Diagnosis & Therapy. 2014 Vol. 4. No. 5.
13. Cleveland Clinic. Fish Faceoff: Wild Salmon vs. Farmed Salmon.
14. Allen RW. et a., "Cinnamon use in type 2 diabetes: an updated systematic review and meta-analysis." Ann Fam Med. 2013 Sep-Oct;11(5):452-9.
15. Diabetes Research and Action Education Foundation. Cinnamon and Diabetes.
16. Kelemen LE., et al. "Associations of dietary protein with disease and mortality in a prospective study of postmenopausal women." Am J Epidemiol. 2005 Feb 1;161(3):239-49.
17. Type 2 diabetes mellitus and diet (Beyond the Basics). UpToDate. Apr 13, 2015