Eating for Type 2 Diabetes and Prediabetes: Everything You Need to Know

November is Diabetes Awareness Month, so I decided it was about time I wrote a comprehensive post about eating with blood sugar in mind. I might have gotten carried away. I might have accidentally written a book.

But seriously, in my individual consults this is probably the number one topic of discussion. More than two-thirds of people who have a heart attack have either diabetes or prediabetes, and often it’s diagnosed shortly after their event.

Talk about a 1-2 punch. A heart attack is scary enough, and you get your blood drawn and surprise, you have another problem to contend with.

Of course diabetes doesn’t affect just people with heart disease. About one in three Canadian adults are living with either diabetes or prediabetes, comparable to the reader survey I did last month, where 32% responded that they have one or the other, and would like to learn more.

Good news

As with heart disease, self-care in diabetes can make a big difference towards your wellbeing. Plus healthy habits for diabetes aren’t that different than for heart health in general, at least for type 2 diabetes in the early stages.

Because of the overlap between these two conditions, the nutrition guidance for one is quite similar to the other. If you’ve been following me and reading about heart-healthy eating, not much has to change.

A diabetes primer

When people are newly diagnosed I usually start with an introduction to diabetes. Whether they’ve had that from another healthcare professional or not, I find most are still fuzzy on the fundamentals.

If you’ve had diabetes for many years, you may notice a few things have changed. Treatment and nutrition guidance evolves, as science does, so consider this a chance to stay up to date!

Here goes…

Insulin

It helps to know a little about insulin, which is a hormone made in the pancreas that regulates the amount of sugar (glucose) in the blood. Surprise — we need some sugar in our blood. We use it as fuel — breathing, thinking, dancing, talking, you name it — and insulin helps make that happen. But too much sugar in the blood, of course, over time, can cause problems.

But at the root of it, diabetes is an insulin problem. As Diabetes Canada explains it, “Your body either can’t produce insulin or can’t properly use the insulin it produces,” resulting in blood sugar levels that are sometimes too high or low.

Types of diabetes

The main types of diabetes are:

• Type 1, when the pancreas can no longer make insulin because the body attacks it by mistake (i.e. it’s an autoimmune disease). It typically develops in childhood or adolescence, for reasons we still don’t understand, and people with type 1 diabetes have to take insulin to survive. Managing type 1 diabetes is a full-time job.
• Type 2 diabetes, on the other hand, is when the body can’t properly use insulin and/or make enough of it. It usually develops in adulthood. Although not as onerous as type 1, it still requires significant self-care.
  • Prediabetes is simply an early warning of possible type 2 diabetes. Blood sugars are higher than normal, but not as high as with diabetes. 
• Gestational diabetes is like type 2 diabetes, but it develops during pregnancy and then usually resolves. It may, however, increase the risk of developing diabetes (and heart disease) later in life. 

Most of this post applies to type 2 and prediabetes.

How is diabetes diagnosed?

These days, your doctor will probably make the diagnosis using a blood test called hemoglobin A1C (A1C). A1C reflects your blood sugar levels for the past three months, so it’s not just about what you ate the day before you went to the lab. Also, they won’t check it more often than every three months, because it doesn’t change that fast.

You’ll likely do a second test to confirm, but generally if it’s:

• 6-6.4%, it’s considered prediabetes
• 6.5% or more, it’s diabetes.

I always think it’s worth mentioning that the American Diabetes Association classifies an A1C of 5.7% or more as prediabetes. They just sound the early warning bell earlier.

So if your A1C is 5.9% and you’re in Canada, your doctor might not say anything, depending on other priorities, but especially if you have some of the risk factors below, it never hurts to think about diabetes prevention.

Complications of diabetes

The bad news is that if not well managed, the complications of diabetes can be pretty dire, including problems with your heart, brain, eyes, kidneys, feet and legs, even erectile dysfunction. Pretty much anywhere there are arteries. People with diabetes are also at higher risk for anxiety and depression.

Some diabetes complications — including heart disease — may begin during prediabetes, so it makes sense to heed the warning.

The good news is that the complications are  less likely for people who are able to keep their blood sugars mostly in the target range and address heart disease risk factors like inactivity, blood pressure, cholesterol, and smoking.

Risk factors: Why did this happen to me?

There’s a lot of shame and blame around diabetes, so let’s nip that in the bud. Diabetes is not your fault. Full stop.

We have little to no control over numerous risk factors for type 2 diabetes, starting with age (40+),  family history, and ethnic background. Certain medications also raise diabetes risk, as well as some health conditions, like obstructive sleep apnea.

You won’t hear as much about them, but there are also well-established links between diabetes and low socioeconomic status (i.e. poverty, education, and more) as well as trauma, including racism, weight stigma, and adverse childhood events. Clearly none of these are your fault!

Other risk factors like high blood pressure, cholesterol, smoking, and sedentary living are modifiable, but I think we can all agree that there are formidable barriers to addressing them. Doable, but easier for some than others.

And yes, having a higher weight is a risk factor, but as we’ve talked about here a lot, there are many contributors to THAT which aren’t your fault either.

Point is, there’s a lot more to diabetes than “Oops, too many chips.” If you haven’t been active or eating your veggies, I bet it’s because you had other priorities, like caring for loved ones or paying the bills. We’re all doing the best we can with the cards we’re dealt.

But if you’ve been diagnosed with type 2 diabetes or prediabetes, you might be ready to really prioritize those healthy habits. Here’s what helps…

Staying well with diabetes

I’m going to talk primarily about nutrition below, of course, but let’s keep it in perspective. That’s only one aspect of diabetes care. Physical activity is also important, of course, as are regular checkups and medications.

People sometimes think of medication as something to avoid, but I’d challenge that! As people age, diabetes typically progresses, despite their best efforts. If medication can help you with blood sugars and keep your blood vessels healthy, by all means, take advantage if you’re able to. (Cost of medication… another rant altogether.)

As with heart disease, addressing sleep difficulties and practicing stress management and relaxation can help keep you well too, and (bonus!) likely make healthy eating and movement more doable.

And while these aren’t readily controllable, it helps to know that illnesses, pain, some medications, and even menstruation can affect your blood sugars. So if they’re out of whack and you’re doing all you can, that might be the reason.

Finally, think of education as a cornerstone of diabetes management. This is a complex condition. Your family doctor may not have a lot of time to teach you everything you need to know, so ask if there are classes you can take, and seek out specialized healthcare professionals such as a diabetes nurse, an endocrinologist (a doctor who specializes in diabetes), an eye doctor, a foot doctor, a dietitian, and perhaps a therapist or kinesiologist.

If one of these people is a Certified Diabetes Educator (CDE), even better. CDEs really know their stuff. Most chain pharmacies have a CDE pharmacist on staff, and you may be able to set up a free appointment with them to learn more about blood sugar monitoring, diabetes medications, and more.

Weight loss

You’ll likely hear a lot about weight loss if you’re over the magic (somewhat arbitrary) BMI cutoff. While it can be effective for improving blood sugars and other health markers, at least in the short run, most people regain the weight within a few years, if not sooner. The other challenge with weight loss is that we don’t have studies showing that it actually improves cardiovascular outcomes. (In fact the best evidence shows that it doesn’t.)

For the most part, what you do matters more than what you weigh. For heart health and diabetes, we have way more evidence of long-term benefit for healthy eating, physical activity, medications, etc, than for weight loss. That’s what you can more readily control anyhow, so I say focus on that.

What about blood sugar testing?

Checking your blood sugars can help with diabetes self-care, but not everybody needs to do it every day. Ask your diabetes team — they can help you figure out the right approach for you.

When you do check your blood sugars, generally we aim for readings between 4 and 7 mmol/L when fasting, versus 5 and 10 mmol/L two hours after eating.

Your doctor should also check your A1C periodically. Generally we like to see A1C below 7%, but they may suggest a different target for you.

Okay, all that said, let’s talk food!

Nutrition for diabetes

First, terminology

You may know these terms, but humour me for folks closer to the start of this journey. We don’t want to lose anyone.

Carbohydrates

Carbohydrates include sugars, starch, and fibre. You probably think of bread, potatoes, rice, pasta, and sugary foods when you hear the word carbohydrate, but many people don’t realize that carbohydrates are also found in fruit, vegetables, milk, yogurt, and legumes (dried beans, peas, and lentils).

Carbs do raise blood sugar levels, but some of them also come packed with health-boosting nutrition and energy, not to mention deliciousness. The question is, how can you get the benefits without your blood sugar going too high? Read on…

Fibre

Fibre, found only in plant foods, is a special kind of carbohydrate, because we can’t digest or absorb it. “In one end and out the other,” I often say, doing so much good along the way!

Fibre slows down digestion of carbohydrate-containing foods, easing their impact on blood sugars. It can also help lower your cholesterol and reduce your risk for heart problems, not to mention the gut health benefits. Yay for fibre!

Good sources? Whole grains, legumes, fruit, vegetables, nuts, seeds, and (bonus) dark chocolate. (It’s true… check the label!)

Protein

Protein is found throughout our bodies, including muscles, of course, but also other tissues, skin, nails, hair, hormones, and enzymes. People often think of meat, fish, and poultry when we talk about protein, but of course it’s also found in legumes, eggs, and milk products. It’s also in nuts, seeds, and grain products, in smaller amounts.

Yes pasta has protein! Who knew?

All protein-containing foods can actually be turned into blood glucose, but not as readily as carbohydrates. And if you eat them with carbohydrates, it eases the blood sugar rise. (Yep, that’s another of the tricks.)

Next, let’s bust some diabetes myths

Myth: You should follow the “diabetic diet”

Nope. As with heart health, there’s no one right way to eat for diabetes/prediabetes. There are many options! There are principles for sure, but you can factor in your unique preferences and values and eat in your Sweet Spot, as I always say.

If you’ve followed me for a while, you know that I’m a big proponent of flexibility and autonomy when it comes to eating. You might benefit from learning a bit about nutrition and diabetes, but ultimately, you know what works for you.

And as the Intuitive Eating people put it, feel free to ignore the “food police,” whether they’re real people in your life or their voices inside your head. Commenting on anyone else’s food choices is always offside.

Myth: Certain foods are off-limits

Again no. While you might expect that carbohydrate-rich foods, like bread, pasta, and potatoes, would be banned in diabetes, that is definitely not the case.

In fact, that kind of thinking can be counterproductive. We crave the forbidden fruit, right? Restriction often eventually triggers what feels like overeating. It’s just your body’s way of saying “I need more food!” Nonetheless it makes people feel guilty and eventually go back to restricting, continuing an endless on/off the diet cycle. I’ve heard it so many times.

Sometimes called the restrict/binge cycle, this pattern may actually be worse for your diabetes. Higher “glucose variability,” it turns out, is also associated with diabetes complications, not to mention the effect on your relationship with food, peace of mind, and self-esteem.

So how about we agree that a cookie is just a cookie? No big deal in the grand scheme.

Myth: No sugar allowed

Let’s let this one go too. Sugar is not off limits. Canada’s diabetes guidelines say it’s okay to have up to 10% of your calories from added sugars, preferably in exchange for other carbohydrates in mixed meals, assuming your blood sugar and other risk factors are at target. Canada’s Heart & Stroke Foundation says to ideally aim for 5% or less.

What does that mean, practically speaking? That 5-10% is where the often quoted 25-50 grams or 6-12 teaspoons of added/free sugar guidance comes from. It’s based on 2000 calories, which is just a nice round number, but keep in mind that some will eat more, some less.

And we’re not talking about the sugar in an apple or a glass of milk — just the sugars added to foods or not part of a whole, nutritious food (i.e. “free” sugars, as in juices, honey, and syrups).

Compare that 25-50 gram recommendation to this bottle of orange juice, and you’ll see why we focus first on avoiding sugar in beverages. They can hide A LOT of sugar, and they don’t trigger our satiety response the same way that solid food does. Have a close look at anything you habitually drink.

But a teaspoon of sugar on your morning oatmeal or a square of chocolate with dinner? Let’s not lose any sleep over that.

(By the way, people with long-time diabetes, this is one of those things that has changed over the years, if you learned about diabetes some time ago.)

Myth: Fruit has too much sugar

Not true! Even people with diabetes who eat more than three servings a day of fruit have a decreased risk of mortality, so if you enjoy it, (whole) fruit is still on the menu.

You may find it helps your blood sugars to spread your fruit across the day, instead of having them all at once.

But no need to avoid fruit!

Myth: A low-carbohydrate diet is the best for managing diabetes

No. There’s no best diet. Low-carb diets can lower blood sugar and weight, at least in the short run, but we don’t have studies showing that those benefits last more than a year or two, or result in lower rates of heart disease and other diabetes complications.

But we do know that many people find it hard to stay on a low-carb diet indefinitely. Low-carb diets make it harder to get enough fibre and other nutrients too.

It is an option, if you feel that eating this way (for life) is for you. It’s even in the Canadian diabetes guidelines now, although it’s just one in a list of options. If you want to go this route, work with your doctor, because you may need medication adjustments. And a dietitian can be helpful, to figure out strategies to meet your nutritional needs in a heart-healthy way.

But there are definitely other healthy ways to eat for diabetes, so you don’t have to go this route. (More about low-carb diets here from Diabetes Canada.)

Myth: You should drink red wine for heart health

Drinking in moderation with diabetes is okay, and might be even a teensy bit beneficial for heart health, but the case isn’t so compelling as to suggest you should drink for health.

And the downsides of excessive drinking are serious. In terms of heart health, it can contribute to higher blood pressure, weight gain, and high triglycerides. And alcohol is a carcinogen, even in moderate amounts. Finally for people taking insulin or certain other diabetes medications, it can cause low blood sugar as well. (More on that here from Diabetes Canada.)

So enjoy a bit if you like, but definitely not a must-have for heart health, with or without diabetes.

5 keys to eating for diabetes

Okay, so what can you do? While it’s just one of several aspects of diabetes care, looking at your eating habits can be potentially lower your A1C by 1-2%, possibly with some beneficial side effects. Yay!

The priorities are pretty similar to what we recommend for heart health, with a few twists.

Key #1: Balance your plate!

You’ve seen it before, I’m sure, because it works!

This simple guide to meal planning incorporates a lot of blood sugar management and heart-healthy eating principles: Load up on vegetables and fruit, include a moderate amount of whole grains or starchy vegetables and a protein-rich food at every meal.

The whole grains and even starchy vegetables like potato help with that all-important fibre. Vegetables and fruit contribute too. The protein foods help blunt the blood sugar rise and might even add fibre, if they come from plants.

With diabetes, you might want to have more vegetables on the “vegetable & fruit” half of the plate, as in this Harvard Healthy Eating Plate variation. Both are great sources of heart-healthy nutrients, but vegetables typically have less than half the carbohydrate content, so they’re easier on blood sugars.

If you miss something at a meal, or the proportions aren’t quite like this, no worries! It’s just a guide afterall, but an evidence-based and elegant one at that.

Key #2: Consistent timing and intake across the day

Next, try to have a similarly-sized balanced meal like that three times a day. If you go long enough between meals, say 5-6 hours, it can help to add a healthy snack — basically a mini version of that. (You might skip the whole grain/starch piece at snacks if you’re not as hungry. Just fruit or veg and protein will do.)

In my experience, people usually have something like that balanced plate for supper (although not always in these proportions). But at breakfast and lunch, components are often missing. Think about your breakfast today. Did it have each of these components, in about these proportions? If not, that might be something to work towards.

Keeping potatoes, rice, or pasta to a tidy quarter of your plate is tough to do if you’re really hungry. Meat too, for that matter. Eating regularly throughout the day can help with that.

Key #3: Choose mostly low glycemic index grains/starches

The glycemic index (GI) of a food reflects how quickly it increases your blood sugar. Adding more low (and less high) GI foods to your meals can help keep blood sugars in target (and even lower LDL cholesterol a little).

What foods are we talking about? Focus on the grains and starches, because they contribute the most carbohydrate.

You can find a more extensive list here, but don’t get obsessive about glycemic index! It’s just one consideration. It doesn’t matter as much for (whole) fruit and vegetables, because they don’t typically add up to that many carbohydrates. So don’t sweat the higher GI vegetables like carrots. Trust me, carrots are the least of our worries.

If you like higher GI foods like potatoes, white rice, and white bread, that’s okay! Even having them less often can help, so experiment with some of those lower GI starches. And when you do have them, try to keep to that 1/4 plate-worth, and balance with those veggies and protein foods as in key #1.

Key #4: Eat for heart health

People with diabetes are about twice as likely to have heart disease or stroke, so everything I’ve mentioned so far is consistent with guidance for heart health.

But I haven’t yet talked about sodium and healthy fats. So just like we say for heart health, try to keep your sodium below about 2000mg a day. That’s about more than banning salt. About 3/4 of our sodium comes from processed and restaurant foods, so check the labels, and choose mostly those with 5% or less for sodium. (More on sodium here).

In terms of healthy fats, we’re aiming for more from foods like nuts, seeds, fish, and extra-virgin olive oil, less from foods like butter, sausage, and ice cream. (More unsaturated, less saturated and trans fats, for the label-readers.)

As with all of my other advice, we’re not looking for all or nothing here. Balance with your preferences and find your sweet spot.

Key #5: Slow it down

Finally, as with heart health, take a deep breath and slowwwww it down in the food department.

Specifically I mean try to eat more minimally-processed (and less highly-processed) foods. That usually means taking some time to plan, prepare, and even eat.

But it’s okay to use convenience foods! The trick is to choose packaged foods closer to their original natural state, with minimal added sugar, sodium, and other additives.

Think canned no-salt-added beans and tomato products, frozen fruit and vegetables. Frozen raspberries versus raspberry jam. A frozen entree with brown rice instead of white. Plain brown converted rice instead of seasoned (white) minute rice. Quick oats in a big bag versus instant oats in packets.

The list goes on. (I’ve got a blog post in me about this alone.)

And by slow it down, I’m also thinking of mindful eating, as I discussed on the blog a few weeks ago. Research into this is very limited, but one study found that a mindful eating program lowered blood sugars and even weight as well as conventional diabetes education. Perhaps something to explore?

And finally, see if you can make time to eat with others. While that might not have a direct impact on blood sugars, breaking bread with loved ones is one of life’s great pleasures and can help strengthen social connections, which are tied to longevity and wellbeing. Life is not all about veggies and carbs, right? (Goodness I hope not.)

Keeping it simple

I wrote a lot here, in an attempt to answer so many of the questions I’ve heard over the years, but eating for diabetes doesn’t have to be complicated. It doesn’t mean you have to live without your favourite foods or follow a strict diet.

As with heart health, yes, aim to eat more veggies, fruit, whole grains, legumes, nuts, seeds, fish, lower-fat dairy and meats if you like. Minimize processed meat, refined grains, sugar, and alcohol. Include more lower GI grains and starches. Keep this model in mind when planning and dishing out food, and spread your food out over the course of the day.

Eating well for type 2 and prediabetes doesn’t have to be more complicated than that. If you’re doing it consistently and still have trouble keeping your blood sugars in target, talk to your diabetes team.

And while healthy eating can have a positive impact on your blood sugars and other aspects of heart health, but it’s not the end-all be-all.

If your eating habits are a solid 7 out of 10, but you’re walking, seeing friends, sleeping well, and seeing the doctor regularly, that’s better for you than being a stressed out 10/10 dieter any day.