Sucralose
Also known as: Splenda
Chlorinated sucrose derivative. 600× sweeter, zero calories. New questions on heat stability and gut microbiome.
At a glance
How Sucralose compares to table sugar on the three numbers most people actually want.
Ten-metric breakdown
See methodology →- Taste qualityWeight 20%85
- Glycemic impactWeight 18%45
- NaturalnessWeight 10%10
- Tooth friendlinessWeight 8%90
- Overall safetyWeight 14%Pending
- Digestive comfortWeight 8%75
- Gut microbiomeWeight 8%Pending
- AftertasteWeight 6%Pending
- SustainabilityWeight 4%Pending
- Allergen safetyWeight 4%85
Source: public.sweeteners snapshot, refreshed 2026-04-27. "Pending" cells are catalogued but not yet graded by SweetSpot research.
What it actually is
Sucralose is sucrose with three hydroxyl groups replaced by chlorine atoms. The chlorination prevents the body from metabolising it: ~85% passes through unchanged, ~15% is absorbed and excreted.
Two evolving concerns. First, heat stability: long-running assumptions that sucralose was inert at oven temperatures have been challenged by 2023 work showing it forms chlorinated breakdown products including the genotoxic compound sucralose-6-acetate at baking heat. Second, the gut microbiome: animal and human studies show sucralose can shift microbial composition, with unclear long-term consequences.
Regulatory bodies still consider it safe within the ADI, but the picture is more nuanced than 'inert sweetener' from 20 years ago. If you bake heavily with it, the heat-stability issue is the most actionable concern.
- Sugar-like taste — minimal aftertaste
- Zero calories, zero glycemic impact
- High ADI — practically unreachable in normal use
- 2023 evidence of genotoxic breakdown products at baking heat
- Microbiome shifts in animal and human studies
- Heavy splash of maltodextrin in retail Splenda
Regulatory status
In practice
- Cold beverages, no-bake desserts
- Heavy baking use
- Microbiome concerns
Splenda, Diet Snapple, many protein powders
The evidence
Selected peer-reviewed sources behind the score. Open access where possible. Read our scoring methodology for how we weight evidence tiers.
Recommended swaps
Higher-scoring alternatives that perform similarly in use.
Mogrosides from Siraitia grosvenorii. 150–250× sweeter, no glycemic effect, cleaner aftertaste than stevia.
A rare sugar that tastes 70% as sweet as sucrose with ~10% the calories and a negligible — sometimes mildly suppressive — insulin response.
Steviol glycosides from Stevia rebaudiana. 200–400× sweeter than sugar, zero glycemic.