Blackberries
One of the highest-fiber fruits by weight. More than half the carbohydrate is fiber, which leaves very little net carbohydrate.
FatTonic Facts
Blackberries · per serving 1 cup (144g)
Excellent · strongly supports fat-burning
| Factor | Amount | Points |
|---|---|---|
| Start | 100.0 | |
| Glycemic load | 2 | −4.4 |
| Sugar (g) | 7 | −5.6 |
| Processing | whole | 0.0 |
| Fiber (g) | 8 | +12.8 |
| Protein (g) | 2 | +1.4 |
| Capped at 100 | raw 104.2 | = 100 |
| Glycemic index | no published test found | |
| Carbs (g) | 14 | |
| Fat (g) | 1 |
Score model v1
Nutrients: USDA FoodData Central, record 173946 (Blackberries, raw), public domain, checked 2 Oct 2026.
Glycemic index: no published test found. Searched 26 Oct 2026 in Atkinson et al., International Tables of Glycemic Index and Glycemic Load Values: 2008: Table A1 tests only a blackberry fruit spread and a blackberry fruit leather (nos. 963, 964), not fresh blackberries, the food as served. The score still uses 25, a value with no recorded source, until a test is found.
Per 100 g (USDA record; serving 144 g): carbs 9.6, sugar 4.9, fiber 5.3, protein 1.4, fat 0.5 g.
What this means for fat-burning
Why this score: fiber 8 g set it, +12.8 points. Source: USDA FoodData Central, FDC 173946.
The fiber slows digestion and blunts the insulin response.
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Among the 200 rated foods
Blackberries scores 100, rated Excellent. It scores higher than 75% of the 200 rated foods.
Rated foods per band: Avoid 0–19: 11; Poor 20–39: 23; Moderate 40–59: 34; Good 60–79: 45; Excellent 80–100: 87.
Frequently asked questions
Does blackberries spike insulin?
Glycemic load 2 for 1 cup (144g); FatTonic Score 100/100 — it strongly supports fat-burning.
Is blackberries good for fat loss?
Excellent (100/100): blackberries strongly supports fat-burning.
Better in fruit
Blackberries ties for the best in fruit on this index.