Conventional science tells us that fruit is a nutritious and essential part of any balanced diet. But is this the case when you’re following keto?
Fruit contains natural sugars and can be healthy in moderation, but it can still be problematic when it comes to keto and fat loss.
Find out how fruit affects your body and learn the difference between keto fruit and fruit that is not keto-friendly.
Fruit is often portrayed as nature’s candy, and for good reason. Fruit is packed with sugar (known as fructose), and like most candy, it will spike your blood sugar levels when you eat it.
When your blood glucose levels spike, they force your body to release insulin. While this is a natural process that helps regulate blood sugar levels, chronic high blood sugar followed by insulin output is a roller coaster you want to get off of. And the ketogenic diet can help. Here’s how:
Insulin is known as the “fat storage” hormone. Insulin tells your body to store (or hold onto) body fat. In ketosis, you want to break fat down and use it for energy. If your blood sugar levels continuously spike and drop (or stay elevated), your insulin will do the same.
This reaction halts fat-burning potential and prevents ketone production.
But when you’re on a keto diet, blood sugar stays relatively stable and you release less insulin. This results in more fat burning and more ketone production.
Because most fruit is loaded with sugar (aka the carbohydrate you most want to avoid on a ketogenic diet), it’s not an ideal keto food.
Not only will sugar spike your blood sugar, but it’s also been shown to trigger reward-and-craving areas in the brain — comparable to the effect of addictive drugs[*].
This addictive cycle leads to cravings and can stall fat-burning, resulting in weight gain and sluggishness.
Obviously, processed sugars and refined carbohydrates play the biggest role in this addiction. But could nature’s candy be contributing to your cravings and stalls in fat loss as well?
Currently, research is lacking in this area. As far as fruit and keto go, the main challenge is finding fruits with the lowest sugar and carbohydrate content.
Here’s a list of high-sugar fruits you should limit or avoid on a keto diet:
- Cantaloupe melon
- Honeydew melon
- Dried fruits, fruit juice, and non-keto smoothies
Although you have to limit your fruit intake to remain in ketosis, this doesn’t mean all fruit is forbidden.
The key is watching your net carbs for the day, and not exceeding your daily allowance. To stay in ketosis, your daily carb count should be roughly 5-10% of your daily calorie intake. This typically equates to about 25-30 grams of net carbs per day (or less than 50 grams of total carbs per day).
Net carbs are calculated by subtracting fiber from the total carbs (Total Carbs – Fiber = Net Carbs). Some people also subtract half of the total sugar alcohols and allulose from their total carb count (Total Carbs – Fiber – ½ Total Sugar Alcohols = Net Carbs).
The reason you count net carbs on keto is that dietary fiber has no impact on blood glucose levels. It’s non-digestible, meaning it won’t spike insulin or kick you out of ketosis.
That said — a lot of keto dieters count total carbs, not net carbs. Especially if they’re trying to lose weight.
Please note that it’s incredibly important to test your ketone levels any time you’re introducing carbohydrate-laden foods into your diet. That way you’ll know how the new changes affect your ketone levels.
This may come as a surprise, but there is one fruit you can eat generously on keto:
Yes, you read that right. Avocado is a fruit, not a vegetable. In fact, it’s the lowest-carb fruit there is and one of the best keto foods in general.
With an incredible amount of nutrients (including healthy fats, vitamins, minerals, fiber, protein, antioxidants, and phytonutrients), avocados are nutritional powerhouses.
Avocados should be a staple in any diet, but particularly so in the diet of anyone following a keto meal plan.
There’s a common misconception that avocados should be avoided because of their high-carb content. However, the ratio of carbs, fiber, fat, protein, and other nutrients make avocados a keto superfood.
See for yourself and check out the nutrition facts below.
One half of a medium-sized avocado (~ 70 grams) has[*]:
- 112 calories
- 10g fat
- 6g carbs
- 5g fiber
- 1g net carb
- 1.4g protein
The benefits of consuming avocados include:
- Improved heart health[*]
- Healthy skin, eyes, and hair[*]
- Lower risk for metabolic syndrome[*]
- Aid in weight loss [*]
- Cancer prevention[*]
- Manage osteoarthritis[*]
- Protection against insulin resistance and diabetes[*]
Tip: Buy avocados in bulk when they’re on sale and keep them in your refrigerator to prevent them from going bad. They can last for weeks in the fridge.
Other Keto-Friendly Fruits
Although a bit higher in sugar, berries are OK on keto.
Like avocados, berries are loaded with antioxidants, vitamins, and minerals while still being low in carbs and high in fiber.
Consuming berries (such as blackberries, raspberries, strawberries, and blueberries) in small amounts can allow you to stay in ketosis. Check out these decadent strawberry fat bombs for a sweet yet keto-friendly treat.
- Blackberries: 14g of total carbs, 7g of sugar, 8g of fiber and 6g of net carbs
- Raspberries: 15g of total carbs, 5g of sugar, 8g of fiber and 7g of net carbs
- Strawberries: 11g of total carbs, 7g of sugar, 3g of fiber and 8g of net carbs
- Blueberries: 21g of total carbs, 15g of sugar, 4g of fiber and 17g of net carbs
Make sure you keep track when eating berries and consume them in moderation. They can easily make you go over your net carb limit and hinder your fat-burning goals.
Too much fruit can keep you from getting into ketosis. And while fruit is touted as a health food, high fructose intake can lead to weight gain and chronic high blood sugar. Here are just a few ways too much high-sugar fruit can keep you from your goals:
#1: Hunger and Cravings
When you eat fruit as a standalone snack, you’ll probably feel full for half an hour. After that, hunger sets in again. This is because fruit doesn’t have enough fat or protein to keep you satiated.
Although fruit does contain fiber to keep cravings at bay, it’s usually not enough to prevent the inevitable blood sugar crash. Once that blood glucose starts crashing, the hunger and cravings begin to surface again.
#2: Potential Overeating
Aside from the blood sugar issue, fruit contains a special sugar called fructose.
Did you ever bring home a container of grapes or pineapple, eat a few pieces, and suddenly the entire container was gone?
You’re not alone.
The combination of sneaky fructose with blood sugar spikes (and following dips) is a recipe for disaster. This inadvertently prevents weight loss for many people.
#3: Bloating or Digestion Issues
Fructose can cause bloating because it’s not always efficiently absorbed by the small intestine. This leads to gas and abdominal discomfort — something quite frustrating if you’re trying to lose extra pounds[*].
With agricultural advancements, fruit grows to larger sizes today with higher sugar concentrations than any other time in history. Therefore, most people are consuming more fructose than past generations. Which is just another reason why fructose can cause more harm than good in your weight loss efforts.
Consuming too many citrus fruits like lemons and grapefruits can also lead to digestive issues because of high citric and ascorbic acid. People who suffer from gastrointestinal reflux and those who get upset stomachs after eating citrus should limit consumption.
You’ve heard the saying: “An apple a day keeps the doctor away.” But is this really the case?
Since fruit is a natural food loaded with nutrients, you might think you should eat as much of it as possible. But that’s not quite true.
In moderate amounts fruit can be healthy, providing you with antioxidants, vitamins, and minerals. But when you consume excessive amounts of fruit, the sugar content adds up.
Too much fruit prevents you from entering ketosis. The excess fructose spikes your blood sugar levels and creates unwanted bloat.
If you really want an array of phytonutrients, start to incorporate an array of low-carb vegetables into your diet instead. Or check out a low-sugar, high-quality greens powder to help you meet your daily micronutrient goals.
Fruit has quite a few health benefits, most notably its high volume of essential vitamins and minerals. And yes, it’s very important to get enough of these in your diet. But eating fruit isn’t your only option.
Follow this keto-friendly food list to get your daily dose of vitamins and minerals:
- Keto-friendly non-starchy veggies
- 100% grass-fed and pastured meats
- Nutrient-dense poultry and seafood
- Properly made greens powders
These foods are highly recommended on keto (or any low-carb diet, for that matter). They provide everything you need to improve your health without causing unnecessary spikes in blood sugar and insulin levels.
Still not convinced it’s ok to ditch fruit? One meta-analysis looked at fruit and vegetable consumption in relation to breast cancer risk. Findings showed that vegetable consumption has a higher probability to prevent breast cancer than fruit consumption[*].
When it comes to fruit, focus on getting the majority of your vitamins and minerals from other keto-friendly sources to keep your body in fat-burning mode. Satisfy any sweet cravings with lower-carb keto fruit such as berries (in moderation), and enjoy avocados (the best keto fruit) generously.
Here’s one last tip for you: If you’re curious about how fruit affects you, test your blood glucose levels after consuming a serving. If your blood sugar goes high or low within the next five hours, this indicates you’re sensitive to that particular fruit and should probably avoid it.