To eat fruit or not to eat fruit. That is the question.
It turns out that fruit is a contentious and sometimes confusing topic within the low-carb community. Some low-carb advocates argue that fruit should be strictly limited or avoided altogether, both because of the carbs and because they’re wary of fructose. Yet some of the staunchest carnivore diet proponents are now incorporating fruit and promoting a “meat and fruit” approach. That’s right, carnivore—billed as the ultimate zero-carb diet—now allows fruit (depending on who you ask).
Even for folks who have no particular philosophical sway against or in favor of fruit consumption, it can be hard to decide which fruits, and how much, to include if they’re aiming to reduce carbs.
My stance has always been that fruit is a natural but not necessary part of the human diet. Sure, it’s higher in carbs than meat or vegetables (on average), but fruits also come packaged with fiber, nutrients, and antioxidants that do a body good. Fruit can be a great way to add carbs around workouts if you so desire. Biting into the first perfectly ripe peach of the summer is a wholly hedonic experience.
But for folks watching their carb intake, and especially for those following a very low-carb ketogenic diet, it won’t do to chow down on massive bowls of fruit salad for breakfast. Here’s how I weigh the relative merits of different fruit options.
Choosing the Best Low-Carb Fruits
There’s no definitive algorithm that can spit out a low-carb acceptability rating for a given fruit, but the factors below are the ones I consider relevant to this question.
1. Start with the amount of carbohydrates and fiber in a typical serving.
Carbohydrates because… obviously, and fiber because fiber doesn’t get absorbed and converted into glucose. Instead, it mostly travels through the gut, where commensal microbes “feed” on certain types. That’s why some people only count net carbs, which is total carbs minus fiber.
I don’t bother getting that granular. Counting total carbs is less work and avoids debates about whether to subtract fiber from all sources or only certain ones. Just understand that if you’re comparing two pieces of fruits with similar carb content, the higher fiber one will probably have less of an impact on blood sugar.
You can stop there, or you could also…
2. Consider the antioxidant value.
Antioxidants are compounds that help mitigate cellular damage due to free radicals, and fruit happens to be a terrific source of antioxidants (although herbs and spices are even better). But not all fruit is created equal here. The antioxidant power of different foods is measured by Oxygen Radical Absorbance Capacity, or ORAC.1 Higher is better.
3. Consider the glycemic index (GI) and glycemic load (GL).
Glycemic index measures how much individual foods raise blood sugar when you eat a certain amount of carbohydrate—50 grams of carbs from pineapple or 50 grams of carbohydrates from cantaloupe, for example, compared to 50 grams of carbohydrates from pure glucose. Glycemic load takes into account a typical serving size of each food item, making it more useful. Watermelon, for instance, has a GI in the medium range but a relatively low GL because it’s mostly water.
GI below 55 is considered low, 56 to 69 medium, and 70 or above high.
Low GL is 10 or below, medium is 11 to 19, and high is 20 or greater.
All else being equal, select lower GI/GL fruits.
4. Nutrient profile.
Finally, you could consider what specific nutrients a given fruit is particularly rich in. If you’re trying to boost potassium intake, you might go for avocado, guava, or kiwi. For B6, opt for durian (hold your nose).
Top 8 Low-Carb Fruits
Without further ado, this is my not-entirely-scientific top 8 fruits that I’d recommend for carb-conscious Primal eaters.
Note that the values below are approximate. Depending on what sources you use, you might arrive at slightly different values.
Blackberries, raspberries, strawberries, blueberries, boysenberries—they’re all good! Berries are going to deliver the most antioxidants (highest ORAC scores) of all the fruits on this list.
Carbs per ½-cup serving: 7 to 11 grams (2 to 4 grams of fiber)
ORAC: >4000 (wild blueberries clock in at 9621)
GI: 25 (blackberries, raspberries) to 53 (wild blueberries)
GL: 2 to 4
Cherries are up there with berries in terms of their antioxidant value.
Carbs per ½ cup (about 10 cherries): 12 grams (2 grams fiber)
Kiwis are underappreciated, probably because of their hairy skin and, let’s face it, seedy interior. But one kiwi delivers around 85 percent of your daily vitamin C requirements (almost twice as much as an orange, ounce for ounce) and 31 percent of daily vitamin K.
Carbs per kiwi: 10 grams (2 grams fiber)
Half a grapefruit, which boasts a low glycemic load, will net you around half your vitamin C for the day. Just don’t ruin it by sprinkling sugar on top.
Carbs per ½ medium grapefruit: 14 grams (2 grams fiber)
If you’re looking for a bite-sized fruit morsel to satisfy a small sweet craving, look no further.
Carbs per apricot: 4 grams (1 gram fiber)
Cantaloupe is similar in potassium to banana for about half the carbs. It’s also delicious when wrapped in prosciutto. Not every fruit can say that.
Carbs per 1 cup serving: 13 grams (1.5 grams fiber)
You might be surprised to see a tropical fruit on this list since they tend to be high in carbs. (Indeed, this is the highest-carb option here, though it’s not astronomical by any means.) But guava has a low GI and GL and, more importantly, it is a nutritional powerhouse. One cup of guava blows other fruits out of the water, delivering 500 percent of your daily requirement of vitamin C (five times as much as a medium orange), 688 mg of potassium (about 1.5 medium bananas, which would come packaged with 40 grams of carbs), and 42 percent of the daily value for copper.
Carbs per 1 cup serving: 24 grams (9 grams fiber)
ORAC: 1422 to 2550
Of course, we couldn’t have a best fruits list that omitted the avocado. Besides its healthy fat content—one of the reasons avocado is the darling of the keto world—it packs respectable amounts of B vitamins, folate, vitamin K, potassium, copper, and antioxidants to boot.
Carbs per 1 avocado: 12 grams (9 grams fiber)
Do You Like What You See?
I’m guessing I just angered or bewildered some of you. Rest assured, just because your favorite fruit doesn’t appear here doesn’t mean it’s not “Mark approved.” All of this is somewhat subjective.
I don’t want you overthinking this stuff anyway. The goal is to be mindful about what goes in your body, not to obsess about the relative merits of one plum versus three apricots. That kind of obsessing is worse for your health than any amount of fruit ever could be. Any fruit is going to be a better, more Primal-friendly option than the hyperprocessed junk lining your supermarket shelves.
Ok, that’s it for today. What fruits would have made your list? Any favorites that you feel I overlooked here? Let me know in the comments.
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.