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MP3

The grab-and-go food The ripeness factor Other fruit Three pre-bolus times First thing in the morning Bananas and lows In and out

Bolus 4 · Episode 1644

Bananas

The grab-and-go food that started to feel like an IV of glucose after diagnosis. No label gets read in this one — the whole episode is Jenny's ripeness factor: the same banana is three different foods depending on how yellow it is, and the pre-bolus moves with it.

Scott Benner and Jenny Smith, RD, CDCES, LD

Open the Bolus 4 estimator

No label, no numbers, no estimator on this one. Scott and Jenny never read a carb count for a banana — the episode is about timing, not amount — so this page has no unit figures. Run your own banana through the estimator with your own settings; what's here is the part the estimator can't tell you: how ripe it is. 2:08

01 · Bolus 4 · Episode 1644

The same banana, three times

The carbohydrate doesn't change as a banana ripens. How fast your body can get at it does — the sugars develop, and the glycemic impact climbs with the brown spots.

1:30

Green — not ripe yet

The lowest glycemic impact of the three: the sugars aren't developed. Jenny's husband will eat one at any color; green ones make her cringe, and to Scott they taste powdery, like they're coated in something.

Yellow — just right

Scott's sweet spot — still solid, a little soft, not squishy, no brown. Jenny's too: not banana-bread soft yet. She can smell whether it's ready. Most fruit tastes best exactly where its impact is highest.

Brown spots — squishy

Hits right away — “liquid sugar, almost,” in Scott's phrase. Jenny's face says don't eat them like this. Both of them freeze these for smoothies, banana ice cream or banana bread.

You are not doing the same thing every day. Scott's realization on the recording: people say diabetes gives a different result for the same food eaten the same way — but a banana off the same bunch is a different food each morning as it ripens.

Jenny's ripeness factor · no numbers were read on the recording · Click any item to hear that moment

Where other fruit lands5:12

Jenny's quick map, lower to higher.

Lower on the indexApples, most berries, kiwi — interestingly — and pears while they're still crisp and crunchy like an apple.
Higher when they taste bestTropical fruit and melons are eaten at peak ripeness because that's when the sugar flavor peaks. Most fruit, at the point it tastes best to you, is going to be a higher impact.

02 · Bolus 4 · Episode 1644

Timing, not amount

The bolus for a banana is a pre-bolus problem. Jenny puts three lead times on the three bananas, and Scott adds the morning.

5:57

Jenny's pre-bolus by ripeness5:57

5–10

minutes for a greener banana

If you're a typical 20-minute pre-bolus person for a ripe banana, the greenish one needs a fraction of that.

minutes for a ripe one

The middle of the line. And if the banana is the first thing in your mouth every morning, Jenny would look at longer than that.

The squishy one is off the far end of this scale — it hits you right away.

Takeaway7:15

Timing and amount, on the way out the door

Scott's morning version: bolus while you're getting ready, time it so you hit the kitchen and eat the banana on the way out, and the food catches the insulin's fall and holds you there. A banana is the clearest possible example of timing an amount — understand the impact of the food and put the insulin in front of it.

Bananas and lows7:53

Jenny's fast fixUnsweetened dehydrated banana chips — they work fast for her lows, because the fruit is sliced at its ripest and dried.
Arden's two kinds of lowsOne low just needs the number fixed, and that's juice — no fullness. The other, even at three in the morning, comes with “I feel like this is because I'm hungry,” and for that one she always asks for a banana: it fixes the low and it fills her up.

Takeaway9:24

In and out — nothing to look for later

Is a banana something you have to watch three hours on? No. Nothing lingers; it's the carbohydrate insulin was formulated to cover, in and out. Scott's summary for simple sugars in general: stop the spike before it happens with the right pre-bolus, and use enough insulin that it doesn't make a low later. Look afterward — but what you're checking is your pre-bolus for next time, not anything else.

Take a picture of this one

Things to remember from this one

Everything here is timing. Bring your own carb count.

5–10minutes

of pre-bolus for a greener, less ripe banana — Jenny

20minutes

for a ripe one — longer if it's the first thing you eat in the morning

nowsquishy

a brown-spotted banana hits right away — Scott's “liquid sugar, almost”

0late rise

nothing lingers; check later only to fix the pre-bolus for next time

“The carbohydrate content isn't changing. But how quick your body can digest the carbohydrates, the sugars, changes as the fruit becomes more and more ripe.”

Jenny Smith2:08

“If you're just having a banana every day as they get riper and riper, you are not doing the same thing over and over every day.”

Scott Benner4:47

“Most of the fruits that you're going to eat at that place where they taste the best to you, they're going to be a higher impact.”

Jenny Smith5:12

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