Bladderwrack and blood sugar
What 5 graded rows on bladderwrack agree on for blood sugar, and where they differ. Counted side by side, never averaged.
Consensus finder Rows from the Bladderwrack page, reviewed Oct 21, 2026 How it decides
What the rows agree on
Each block and row is one graded row from the Bladderwrack page, with its PubMed record.
Your question
Bladderwrack and blood sugar
5 rows · 171 peopleMostly no difference: 4 of 5 rows, and most of the people. 1 had mixed results.
- DGrade D× 5
- Rows
- 5
- Trials
- 5
- People
- 171
What the rows share
From the rowsThe best-graded row, grade D, is a randomized trial of 56 people (2022) and found no difference.
The rows run from 18 to 56 people, published from 2011 to 2024: 5 single studies.
The rows
4 no difference · 1 mixed- DGrade DBlood glucose and weight loss with a low-calorie diet · No difference
RCT · n 56 · 2022 · Overweight or obese adults with prediabetes and insulin resistance (Canada)
500 mg/day with diet advice (vs placebo) · 12 weeks
No effect on blood glucose; only small changes in C-peptide during a glucose test were reported, and the authors described the impact as marginal.
Row on the Bladderwrack page · PubMed 35323474 (opens PubMed)
- DGrade DBlood glucose and insulin after bread · No difference
Crossover RCT · n 38 · 2018 · Healthy adults aged 19 to 56 (Australia)
500 mg or 2,000 mg single dose before 50 g carbohydrate · Single doses
Neither dose lowered glucose or insulin after the meal compared with placebo.
Row on the Bladderwrack page · PubMed 29495492 (opens PubMed)
- DGrade DAverage blood glucose on continuous monitoring · No difference
Pilot RCT · n 36 · 2024 · Overweight adults with type 2 diabetes (Netherlands)
5 g/day of dried seaweed · Not stated in the abstract
Weekly average glucose did not change significantly in the Fucus group (n = 10) and did not differ between groups.
Row on the Bladderwrack page · PubMed 38931192 (opens PubMed)
- DGrade DEvening blood glucose after bread · No difference
Crossover RCT · n 18 · 2019 · Healthy adults (Australia)
Single dose before 50 g carbohydrate in the evening (vs two placebos) · Single doses
No effect on evening glucose response in the group as a whole; peak glucose was lower in women only, a subgroup finding.
Row on the Bladderwrack page · PubMed 30813480 (opens PubMed)
- DGrade DGlucose and insulin after a carbohydrate meal · Mixed
Crossover RCT · n 23 · 2011 · Healthy men and women aged 19 to 59 (Canada)
500 mg single dose, 30 minutes before 50 g carbohydrate · Single doses, 1-week washout
The insulin response was 12.1% lower and an insulin-sensitivity index 7.9% higher than placebo, but the glucose response did not change.
Row on the Bladderwrack page · PubMed 22087795 (opens PubMed)