Forbidden Fruit

A week ago, I went to see a dietitian at the endocrinology clinic I go to. The reason for my visit was to get some help figuring out what else I could do on the days I exercise to keep my blood glucose closer to 150 mg/dl during the workout.


While I’m not going dangerously low at the gym, when I check my blood glucose 20 minutes into a workout, and then again at 40 minutes, I often find that I’m around 100 mg/dl. It’s a pretty safe bet that any blood glucose reading at these times will be going down, not up.

So I’ve been brooding about what to do. For the past several months, I’ve been going through two bottles of Gatorade (35 carbs per bottle) during my more intense workouts. But that’s simply become too much high fructose corn syrup (HFCS) for my taste.

When the dietitian recommended some other options, such as fruit juice, bananas, and/or eating more of an actual meal—without bolusing—about an hour before starting my workout, something slowly dawned on me: I’ve been carrying around some rather stupid preconceptions about certain foods over the past 10 months or so. My early days, weeks, and months with Type 1 diabetes created a few neural pathways that only recently—in the past week, actually—have I gone back in to try and clear the mud and weeds from.

Take my relationship to bananas, for example.

One of the things I learned soon after my diagnosis was how carbohydrate-heavy a banana was. In those confusing first few months, my mind spun so many erroneous tidbits of information about bananas, and in fact many other fruits, to such an extreme that I began to see them as dangerous. Avoid bananas because you’ll go high! Don’t eat more than a few strawberries! Ignore the orange juice—use only in case of emergency!

Granted, I was newly diagnosed, and this was a whole new world to take in. But really, how lame indeed that I’ve been holding on to not only my “dangerous fruit” notions, but also quite a few other “umm, duh!” misconceptions. I mean, looking back now it makes little sense that I’d bolus for the 80 grams of carbs in a buttery, cheesy pasta dish; or I’d eat three pieces of pizza, simply enter the carbs in my insulin pump, then think nothing of it; or I’d scoop some potato salad onto my plate at a picnic and think, “That’s about 35 grams”; but a banana, which has a comparable amount of carbohydrate (and is a little healthier than a piece of pizza)—totally forbidden.

I never received misinformation, mind you. My brain (me) was overwhelmed with my new life as a Type 1 and simply chose to misfile some of the info I was taking in, thus creating a few poor dietary instructions. I realize this may not make complete sense, but the unanalyzed logic I carried around seemed completely rational to me at the time.

Over the past week, I’ve altered my preworkout routine, and I’m happy to report that on average I’m down to only one bottle of Gatorade per workout. I’m eating bananas again. I’ve had a few glasses of orange juice. And I’m looking forward to the strawberries from the garden.

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  • suzanne

    Ha! You are so not alone in those initial reactions to dealing with diabetes.
    Turns out if you had a healthy diet before diabetes, you can probably eat most of the same things you used to eat! Including all those yummy fruits & veggies!
    Thanks for the laugh today (with you not at you).

  • Angela

    Have you tried a temporary basal on your pump while you’re working out? My CGM helped me figure out that I need to set mine at 80% for the first 30 minutes of a 45-minute cardio session. Using the temp basal, I don’t have to consume calories while I’m burning them.

  • CalgaryDiabetic

    Yes, it is bewildering in the beggining. Like when I first discovered that exercise increases your blood sugar. I was shocked and this was after 1/2 hour of X-country skiing(a consumption of about 300 KC). Well as my friend Dr. Cox pointed out exercise is stress which shoots adrenaline, cortisol and many others into the blood stream. If you do enough the blood sugar will fall. I find I can waste a least 1000 calories without worring about low blood sugar. The only precaution is not to use fast acting insulin before the session. And of course lots of fruit and no Gator Aid ever even when dying of hypoglycemia (i.e. fructose does not help on the short term it takes a long time to rearrange into glucose).

  • C7

    I was diagnosed (type 1) in my mid 30s and have sinced struggled to find the right rythm in my workouts. I’ve started eating a nut bar called Go Lower which uses Oligofructose (chickory root) as the sweetener. They taste great and give me long lasting energy without a big spike.

    I also find that eating one 12 carb Fruitabu fruit leather before and midway through gives me enough to get through an hour of cardio without a big drop during or after. I still end up rising a bit later on.

    Your not alone out there. Many Type 1’s have been down this path before. Keep exercising and finding the things that work for you!

  • acampbell

    Hi Eric,
    As a dietitian, I couldn’t resist commenting —and thanking you—for your posting. So many people view fruit as truly being forbidden when they have diabetes. While it’s certainly a source of carbs, it’s also a powerhouse of nutrition, more so than many of the refined carbs that we often eat. Also, Gatorade will work for treating lows; it may take longer to work, not so much because of its fructose content, but because 8 ounces contains 14 grams of carbohydrate, whereas 4 ounces of fruit juice contains 15 grams of carbohydrate. And good suggestion by Angela to set a temp basal so you don’t have to snack so much when exercising.

  • Al in Cal

    I totally agree with avoiding high-fructose corn syrup. Why don’t you check out a different drink for replenishment: chocolate milk! Several months ago I read someplace that this is actually the best thing, even better than Gatorade. Sorry I don’t remember the source, but with some Internet search, you might find it. I think it was in either Men’s Health or another reputable magazine. As for avoiding fruit, as long as you stick to serving limits, you absolutely SHOULD eat fruit every day, and some diabetes pros recommend it at every meal. Whole fruit is better than juice, because it has fiber and bulk, and it can’t be chugged. Going without fruit or fruit juice will just deprive your body of needed nutrients. If you’re dying of thirst, quench that thirst with a zero-carb drink (either plain water, or ice tea with artificial sweetener). Then when you drink a carb-filled beverage, you won’t chug, and thus won’t consume too many carbs.
    Good Luck!

  • sstrumello

    I’m a little late to this posting, but I felt I should comment anyway. First is the presumption that you are on an insulin pump; the simple fact is that only an estimated 40% of people with type 1 diabetes are even using pumps, making them a slight minority of people. I am a former pumper myself, and returning to multiple daily injections (MDI) was the best thing I’ve ever done (and no deterioration in my HbA1c), but that’s not particularly relevant to your post except that the comments on reducing basals may not even apply if you’re on MDI. Let me add that the research is virtually conclusive in showing that pumping most benefits certain groups of people: 1) those with poor glycemic control 2) those whose need for basal insulin varies considerably throughout the day or 3) those who are very sensitive to U-100 insulin and need dosage precision smaller than 1/2 unit. But if your control is already good on MDI, you may not see much benefit (and it will cost a LOT more).

    The other element I should note is the comment from acampbell, the dietician who responded. While she’s correct in that fruits are more nutritious than refined carbs, they ARE carbs, and a complex mix of glucose and fructose, the latter of which is typically metabolized in a very unpredictable manner. Also, not all fruits are created equal — in general, most tropical fruits (bananas, citrus fruit, pineapple which tend to be very high in simple sugars) are lower on the nutritional totem pole, vs. more fibrous fruits including apples and pears. Also, don’t forget the calories! You should also know that many high-performance athletes prefer higher-protein levels because it typically is metabolized over a period of 7-10 hours and may better match your post-workout needs than a more rapidly metabolized fruit.

    Although fruit isn’t forbidden, its not exactly the ideal food, either. Carbs require insulin (even when working out) to enter the cells of the body, and insulin is hardly a benign medicine — numerous studies have proven conclusively that excessive insulin is responsible for many health problems, so just remember that eating and covering it with insulin doesn’t define good health or nutrition.