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This post is an update on my experiments measuring the effect of low-carb foods and dietary supplements on blood sugar.
This week, I have the results from low-carb ice creams. Next week I’ll have low-carb breads.
Testing Queue:
- Low-carb foods:
- Meal replacements: in queue, (Ketochow previously reported)
- Flour replacements: in queue
- Tortilla: Reported
- Bread: 9/4/21
- Snack bars: in queue
- Ice cream: This post
- Cereals: Reported
- Supplements:
- Vinegar: in queue
- MSG: Reported
I tested 6 low-carb ice creams from 4 brands (Enlightened, Halo Top, Keto, & Rebel).
All held up to their claims, with relatively low blood sugar impact and taste similar to regular ice cream.
The 6 ice creams had relatively similar blood glucose impact by weight (3-4% of glucose for peak BG/g & 7-10% for iAuC/g) and volume (18-27 mg/dL/cup peak BG & 3,200-4,600 mg/dL/cup iAuC). Of the set, the Keto brand ice cream was ~25% higher than the next worst. Not enough to stop me from eating it, but noticeably worse.
On taste, my favorites were the Rebel Chocolate and Cookies & Cream, but they were all pretty good except for the Keto Triple Chocolate Brownie. Keto brand used erythritol as the only sweetener in the brownie pieces and it crystallized, giving a gritty texture that I really didn’t like. It also didn’t have a strong enough chocolate flavor for my taste.
Does anyone know any other good low-carb ice creams or other low-carb foods I should try?
Details:
- To identify low-carb foods that taste good and have minimal effect on my blood glucose.
- To determine the effect of popular, literature supported dietary supplements on my blood glucose.
Background
Over the past few years, a number of brands of low-carb cereals have come out, with many available in supermarkets. Most of them replace milk with heavy cream and use erythritol or allulose as the primary sweeteners, so I expect their blood glucose impact to be relatively small, but I wanted to test myself to confirm.
Design/Methods
Foods
I tested 6 low-carb ice creams from 4 brands:
- Enlightened
- Halo Top
- Keto
- Rebel
Full nutrient and ingredient info here. Key nutrition facts in the table below.
At 5:00a, I took 4.5u of Novolog (fast acting insulin, duration of 2-4h), then drank a Ketochow shake (website, BG testing) at 5:30a. After that, no food or calorie-containing drinks were consumed and no exercise was performed. Non-calorie-containing drinks were consumed as desired (water, caffeine-free tea, and decaffeinated coffee). At 11am-12 pm, the substance to be tested was eaten as rapidly as comfortable and notes on taste and texture were recorded (before observing any change in blood sugar).
Blood sugar was monitored for 5h using a Dexcom G6. Calibration was performed 15-30 min. before the start of each experiment.
Data Processing & Visualization. iAUC was calculated using the trapezoid method (see data spreadsheet for details). Data was visualized using Tableau.
Medication. During these experiments, I took long-acting basal insulin each evening at 9pm (Lantus, 1.52u) and 2000 mg of metformin and multivitamin each morning at 5am. I did not dose for the experimental food ingested.
- Formatted raw data, peak blood glucose, iAuC, and time to peak data
- Summary data, ingredient details, and taste assessments
Results & Discussion
Changes in blood glucose as a function of time are shown in Figure 1. All ice creams show a longer time to initial rise and longer duration of impact than glucose, though Halo Top is much faster than the rest. This is likely due to the use of skim milk, which contains lactose.All brands had relatively similar blood glucose impact by weight, ranging from 3-4% of glucose for peak BG/g & 7-10% for iAuC/g. The different brands had significantly different amounts of overrun (air mixed into the ice cream), resulting in different densities. Since I typically eat a pint of ice cream in a sitting, I also looked at the blood glucose impact by volume. With the exception of the Keto brand, this resulted in even less variation, 18-20 mg/dL/cup for peak BG & 3,200-3,700 mg/dL/cup iAuC. The Keto brand ice cream was ~25% higher than the next worst, at 27 mg/mg/dL/cup for peak BG & 4,600 mg/dL/cup iAuC. Not enough to stop me from eating it, but noticeably worse.On taste, my favorites were the Rebel Chocolate and Cookies & Cream, but they were all pretty good except for the Keto Triple Chocolate Brownie. Keto brand used erythritol as the only sweetener in the brownie pieces and it crystallized, giving a gritty texture that I really didn’t like. It also didn’t have a strong enough chocolate flavor for my taste.Note: taste and texture observations were recorded when I ate the food. I.e. before I knew its impact on my blood sugar.
Thoughts & Next Experiments
Although the results were good, this study was a lot less interesting than the previous ones. No surprises or significant differences between brands. Generally, it seems like there’s not much variation in the methods to make ice cream low-carb. The one exception I know of, which I didn’t test, is Breyer’s Carb Smart ice cream. They use maltitol as the sugar substitute, which has about half the impact of regular sugar (hence why I didn’t test it).
Does anyone know any other good low-carb ice creams I should try?
As always, please let me know if you have any thoughts or suggestions.
– QD
Hi! I’m loving these experiments! I’m passively learning for my own life.
Fellow MD and T1D here
Thanks!
This is great! Could you run this test on Nick’s ice cream? It’s both keto and low calorie, and corn is the second ingredient – a little suspicious to me but incredible if it holds up to its promise
I tried Nick’s in a follow up post. BG impact was the lowest of any of the ice creams I tried. Texture was fantastic, but the flavor wasn’t as strong as I prefer. Only think you have to watch out for with Nick’s brand is that only some are low-carb and the packaging isn’t super clear.
Have you tested Breyer’s CarbSmart? The texture won me over, but I wonder how it impacts BG compared to the ones above.
I haven’t done detailed testing with it, but Breyer uses malitol as the sugar substitute in CarbSmart. It has ~50% the blood glucose impact of regular sugar, so if you add back half the sugar alcohols to the Net Carbs, that should be about right. I used to eat it a long time ago before the modern allulose-based ice-creams came out and the insulin required was consistent with that estimate (again, not rigorously tested).