If you’ve changed your diet to improve — or even reverse — your prediabetes, you’ve probably cut way back on carbs. And that’s a good thing, especially if those carbs are processed or junky foods.
But not all carbs are bad. In fact, I encourage my clients to eat carbs in the form of non-starchy veggies — leafy greens, broccoli, zucchini, mushrooms, etc. These foods fill you up, add fiber to your diet, and provide nutrients your body needs.
But what about fruit? There are social media gurus who will tell you never to eat fruit if you’re on a low carb diet because it “turns straight into sugar”. And while I don’t recommend loading up on fruit, there is no reason that a moderate amount of fruit eaten wisely can’t be a part of your diet, even if you’re trying to fight prediabetes.
Fruit is Good For You
✔ Loaded with vitamins and minerals
✔ A good source of fiber
✔ A better way to satisfy the occasional sweet tooth than high-sugar, processed desserts
Yes, fruit can affect your blood sugar. More on that in a minute…
But, because of the benefits to eating fruit, I don’t recommend most of my clients eliminate it entirely. Completely eliminating an entire food group is hard to maintain long-term. If you never eat fruit, not only will you miss out on the nutritional benefits, you’ll feel deprived.
You can eat fruit if you’re prediabetic. And if you choose the right fruits and eat them strategically, they don’t have to mess up your blood sugar balance.
Choosing the Right Fruits
I’m going to get a little sciency with you for a minute here. But hang with me. This important info will help you make informed choices when it comes to eating fruit.
First, let’s look at two ways we can measure food’s effect on your blood sugar:
The glycemic index (GI) is a numeric system that ranks foods on a scale of 0 to 100 based on how quickly they cause blood sugar to rise. The higher the number, the more drastic the rise in blood sugar. Conversely, the lower the GI, the slower the rise in blood sugar after you eat that food. Generally, the more processed a food is, the higher the GI score, and the more quickly your blood sugar will rise after eating it.
Many doctors use glycemic index to help people choose which foods to eat. And it’s not a bad system. But, it doesn’t give you all the information. For that you need to know the food's glycemic load.
The glycemic index (explained above) tells you how fast your blood sugar will rise when you eat a certain food. But it doesn’t tell you how high your blood sugar can get when you eat a certain amount of that food. So that’s where the glycemic load calculation comes in.
The glycemic load takes into account both the glycemic index and the carbohydrate content of the food you’ve eaten. And because it’s looking at both quality and quantity of carbs, you get a more complete picture of how that food will affect your blood sugar.
Calculating Glycemic Load (GL)
While there are glycemic load charts available online, you can also calculate glycemic load on your own using a simple formula:
GL = (GI x the amount of carbohydrate) divided by 100
For example, an apple has a glycemic index (GI) of 40 with 15 grams of carbohydrates. So you’d figure out the apple’s glycemic load like this:
Multiply 40 x 15. Then divide the total by 100. So an apple has a glycemic load of 6.
Choosing Fruit With a Low Glycemic Load
When choosing a fruit (or any food) based on glycemic load, keep this scale from the University of California in San Francisco (UCSF) in mind:
Low GL: 10 or less
Medium GL: 11 to 19
High GL: 20 or higher
Your best bet is to choose foods with a glycemic load of 10 or less. I recommend keeping your daily glycemic load under 100.
Oftentimes a food with a low glycemic index will also have a low glycemic load. But this isn’t always the case. It is possible for a food to have a high glycemic index and still land on the low end of the glycemic load scale. Take watermelon for example. It has a high glycemic index (as high as a donut). But when you factor in the carbohydrate amount, the glycemic load is low. So watermelon is a good fruit to choose to keep your blood sugar balanced. I don’t recommend the donut.
Here are some fruits with a low glycemic load:
When It Comes to Fruit, Portion Sizes Matter
Just because a fruit has a low GL doesn’t mean you should eat a bunch of it. Eating a single slice of watermelon shouldn’t have much of an effect on your blood sugar. But dig into ¼ of a giant watermelon with a spoon, all bets are off.
If you aren’t sure how to determine the appropriate portion sizes for you, there are a couple of options:
Check with your practitioner. A knowledgeable nutritionist can help you figure out portion sizes that will be satisfying without raising your blood sugar.
Use a glucometer or continuous glucose monitor to keep track of how what you eat affects your blood sugar. If you eat a food with a low glycemic load, but your blood sugar spikes anyway, you’ll need to reduce your portion size. Or you can be strategic in how you eat it.
The Food Combining Hack
If you eat a piece of fruit all by itself on an empty stomach, your body is going to process it quickly and you may see a more rapid, pronounced rise in blood sugar.
But if you eat that fruit with a protein or good fat, your body will be better able to regulate the change in blood sugar. Proteins and fats slow down the speed at which your body converts carbohydrates into blood glucose, keeping your blood sugar levels more balanced.
So if you notice your blood sugar is spiking after you eat a low GL food, consider adding a protein or fat to it next time. Adding a tablespoon of nut butter to your apple is not only tasty, it will help control your blood sugar and keep you fuller longer!
If you’ve been diagnosed with prediabetes, it can be overwhelming. There is so much information out there — and it all seems to conflict.
If you need help figuring out how to address your prediabetes, I’m here to help. I help people just like you make diet and lifestyle choices that can make a significant difference — not just in your lab numbers, but in how you feel day to day.
You deserve to feel good and live life on your terms. And I’m here to help.