Jackfruit: almost everything tested was the dried green flour

Green jackfruit flour is a different product from the fruit. It is the mature unripe fruit dried and milled, and it is what nearly every human study of jackfruit actually measured. A 2024 systematic review of 11 randomised trials of flour-based foods, at 1.5 to 36 g a day for six weeks to 120 days, listed green jackfruit flour among the flours that improved glucose homeostasis, and did not list it among the flours that improved blood pressure or blood lipids. The review pooled no effect sizes, so that verdict rests on a single trial inside it. Forty adults in Andhra Pradesh who had type 2 diabetes for over a year, all already taking oral antihyperglycaemic drugs and staying on them, replaced an equal volume of rice or wheat flour with 30 g of the flour a day for 12 weeks. Their HbA1c fell 0.25 percentage points further than on placebo flour, p = 0.006, in 20 people per arm at one centre, with no confidence interval reported for the difference between groups. For the fresh fruit on a plate we found no trial at all. There is not even settled agreement about its composition: USDA and the UK table, describing the same raw jackfruit, differ threefold on vitamin B6, 0.329 against 0.11 mg per 100 g. Neither entry is a sampled Foundation Foods record, so no measured range sits behind either figure.

The numbers, per 100 g

How much is actually in it

• The two national food tables disagree about the same raw fruit. USDA puts vitamin B6 in raw jackfruit at 0.329 mg per 100 g and the UK table at 0.11 mg, a threefold gap, with vitamin C 13.7 against 10 mg and potassium 448 against 350 mg. — USDA SR Legacy record Jackfruit, raw (FDC 174687) against CoFID 2021 record Jackfruit, raw (13-259), per 100 g (n = 2 USDA records for jackfruit, 1 CoFID record) Evidence E source
  Vitamin B6 0.329 vs 0.11 mg (67% apart), vitamin C 13.7 vs 10 mg (27%), potassium 448 vs 350 mg (22%). The second USDA record, canned in syrup, falls further still, to vitamin B6 0.044 mg and vitamin C 0.5 mg

What a real portion looks like

• The 30 g daily dose of green jackfruit flour used in the diabetes trial is 108 kcal, 20 g of net carbohydrate and 4 g of fibre, taken as 15 g stirred into breakfast and 15 g into dinner. — intervention material of the 12-week trial in 40 adults with type 2 diabetes, 15 g added to breakfast and 15 g to dinner (n = 30 g a day, split in two) Evidence B source
  30 g green jackfruit flour: 108 kcal, 20 g net carbohydrate, 4 g dietary fibre of which 1 g soluble; 15 g is about 22.5 mL by measuring spoon and replaces an equal volume of rice or wheat flour

What cooking and storage change

• There is no cooking-loss measurement for jackfruit itself. USDA only gives factors for the whole fruit group, and for baked fresh non-citrus fruit they are 80 percent retention of vitamin C, 90 percent of potassium, 95 percent of vitamin B6 and 60 percent of folate. — USDA Table of Nutrient Retention Factors Release 6, group Fruits and Fruit Juices (code 9), method FRUITS,FRESH(NOT CITRUS),BAKED, Retn_Code 151 (n = 16 nutrients in this method row) Evidence E source
  Retained after baking: folate 60%, vitamin C 80%, thiamin 80%, potassium 90%, copper 90%, niacin 90%, calcium 95%, riboflavin 95%, vitamin B6 95%, iron, magnesium, phosphorus, sodium, zinc, choline and vitamin B12 100%

What it does to your health

• In adults with type 2 diabetes who were already taking oral antihyperglycaemic drugs, swapping an equal volume of rice or wheat flour for 30 g a day of green jackfruit flour for 12 weeks lowered HbA1c by 0.25 percentage points more than placebo flour. — 40 adults aged 18 to 60 with type 2 diabetes for over a year, already on oral antihyperglycaemic drugs, Andhra Pradesh, India, 12 weeks (n = 40 randomised, 20 per arm) Evidence B source
  HbA1c change from baseline to week 12: -2.73 mmol/mol (-0.25%) with jackfruit flour vs +0.22 mmol/mol (+0.02%) with placebo flour, p = 0.006; fasting and postprandial glucose also fell further, p = 0.043 and p = 0.001
• A 2024 systematic review of 11 randomised trials of flour-based foods, using 1.5 to 36 g a day for six weeks to 120 days, put green jackfruit flour among the flours that improved glucose homeostasis. It did not list jackfruit flour among the flours that improved blood pressure or blood lipids. — 11 randomised controlled trials of flour-based foods published up to April 2023, PubMed, Scopus and Web of Science (n = 11 randomised controlled trials) Evidence A source
  Flour doses 1.5 to 36 g/day over six weeks to 120 days; green jackfruit flour listed only under glucose homeostasis, while blood pressure gains went to chia, green banana, soy and fenugreek and lipid gains to Brazil nut and chia

Safety, limits and interactions

• Jackfruit can trigger anaphylaxis in people allergic to natural rubber latex. The first published case was a 34-year-old nurse with latex glove eczema who reacted to dried jackfruit and skin-tested positive to jackfruit, latex, kiwi and papaya. — one 34-year-old nurse with chronic hand eczema from latex gloves and a family history of atopy (n = 1) Evidence C source
  Anaphylaxis after eating dried jackfruit; skin prick tests positive to jackfruit, latex glove, kiwi and papaya, negative to banana
• Jackfruit has also caused oral allergy syndrome in a pollen-allergic man who already reacted to raw apple, peach and celery, and the usual birch culprits Bet v 1 and profilin did not explain it. — one 30-year-old man from the Philippines with birch, grass and mugwort pollen allergy (n = 1) Evidence C source
  Oral allergy syndrome after eating jackfruit; in RAST inhibition neither rBet v 1 nor rBet v 2 profilin could inhibit the specific IgE response to jackfruit

Who this works differently for

• Among 87 people on chemotherapy for solid tumours, 6 of 37 who added 30 g a day of green jackfruit flour developed chemotherapy-induced leukopenia, against 20 of 50 in a historical comparison group. The group that ate the flour needed 38 rather than 105 vials of filgrastim. — 87 adults on chemotherapy for solid tumours at one hospital in Kerala, India, mean age 53 and 57 years, at least three cycles each (n = 87 (37 exposed, 50 controls)) Evidence C source
  Leukopenia in 6 of 37 vs 20 of 50 patients and in 14 of 232 vs 37 of 263 cycles; filgrastim 38 vials vs 105 vials, p = 0.00 for cycles and for vials per cycle

The bottom line

The dose in that diabetes trial was 30 g of flour a day, 15 g stirred into breakfast and 15 g into dinner, replacing an equal volume of rice or wheat flour rather than sitting on top of it. Thirty grams carries 108 kcal, 20 g of net carbohydrate and 4 g of fibre of which 1 g is soluble, and those are the manufacturer figures quoted in the trial report rather than an independent assay of what was eaten. How cooking changes jackfruit has never been measured on jackfruit. USDA publishes retention factors by food group, and for fresh non-citrus fruit that is baked the group figures are 60 percent of folate, 80 percent of vitamin C, 90 percent of potassium and 95 percent of vitamin B6, from a table row dated 1975, which makes them a statement about fruit in general. Canning moves more than baking does. The USDA record for jackfruit canned in syrup gives 0.044 mg of vitamin B6 and 0.5 mg of vitamin C per 100 g, against 0.329 and 13.7 mg in the raw record. The caution with a case history behind it is latex allergy. A 34-year-old nurse with hand eczema from latex gloves went into anaphylaxis after eating dried jackfruit and skin-tested positive to jackfruit, latex, kiwi and papaya, negative to banana. Her doctors wrote that they could not settle whether this was cross-reaction with latex or a coincidental second allergy, because no inhibition testing was done. In a second case a 30-year-old man in the Philippines with birch, grass and mugwort pollen allergy got oral allergy syndrome from jackfruit, having already reacted to raw apple, peach and celery, and in his blood neither Bet v 1 nor profilin could inhibit the IgE response, so the allergen behind it stays unnamed. Two published people is the whole allergy record. We found no study of jackfruit in pregnancy or in children, and none that set out to measure an interaction with a medicine, and that is a gap in the evidence rather than a clean bill. One further finding travels widely and deserves slow reading. At a single hospital in Kerala, 6 of 37 people on chemotherapy for solid tumours who added 30 g a day of the green flour developed leukopenia, against 20 of 50 who did not add it, and they needed 38 vials of filgrastim against 105. The comparison group is historical, from before June 2018, nobody was randomised, and the people who ate the flour chose to. It is a reason for someone to run a proper trial. Take it to the team treating you before changing anything during chemotherapy.

Sources

1. jkf-daily-r1-08 · reference dataset
   USDA FDC 174687 Jackfruit, raw (SR Legacy) - Vitamin B-6 0.329 mg - Vitamin C 13.7 mg - Potassium 448 mg per 100 g. CoFID 2021 13-259 Jackfruit, raw - Vitamin B6 0.11 mg - Vitamin C 10 mg - Potassium 350 mg per 100 g. USDA Jackfruit, canned, syrup pack - Vitamin B-6 0.044 mg - Vitamin C 0.5 mg - Potassium 96 mg per 100 g
   USDA FoodData Central SR Legacy and CoFID 2021, Public Health England, Open Government Licence v3.0 · checked 2026-09-24
2. jkf-daily-r1-02 · randomised double-blind placebo-controlled trial, intervention description
   Green jackfruit flour is prepared from dehydrated, mature, unripe jackfruits. Nutritionally, 30 g of green jackfruit flour has calorie of 108 kcal, net carbohydrates of 20 g, and dietary and soluble fiber content of 4 and 1 g.
   Nutr Diabetes, 2021 · checked 2026-09-24
3. jkf-daily-r1-07 · reference dataset
   USDA-RETN-R6:151 FRUITS,FRESH(NOT CITRUS),BAKED, group Fruits and Fruit Juices (code 9), table dated Sep-75 - folate_total_ug 60% - vitamin_c_mg 80% - thiamin_mg 80% - potassium_mg 90% - copper_mg 90% - niacin_mg 90% - calcium_mg 95% - riboflavin_mg 95% - vitamin_b6_mg 95% - iron_mg 100% - magnesium_mg 100% - phosphorus_mg 100% - sodium_mg 100% - zinc_mg 100% - choline_mg 100% - vitamin_b12_ug 100%
   USDA Table of Nutrient Retention Factors, Release 6, 2007 · checked 2026-09-24
4. jkf-daily-r1-01 · randomised double-blind placebo-controlled trial
   A significantly higher reduction in HbA1c was observed in Group A compared to Group B from baseline to week 12 [-2.73 mmol/mol (-0.25%) vs. 0.22 mmol/mol (0.02%), p = 0.006].
   Nutr Diabetes, 2021 · checked 2026-09-24
5. jkf-daily-r1-03 · systematic review of randomised controlled trials
   The amount of flour used in the studies ranged from 1.5 g to 36 g/day, and the supplementation period ranged from six weeks to 120 days. Green jackfruit flour, green banana flour, soy flour, flour from rind of the yellow passion fruit, and fenugreek powder demonstrated significant results in improve parameters of glucose homeostasis.
   Crit Rev Food Sci Nutr, 2024 · checked 2026-09-24
6. jkf-daily-r1-05 · case report
   Here we report the case of a 34-year old nurse who developed anaphylaxis following the ingestion of dried jackfruit (Artocarpus heterophyllus). ... The results of skin prick tests were positive for jackfruit, latex glove, kiwi and papaya, but the test was negative for banana.
   Asian Pac J Allergy Immunol, 2015 · checked 2026-09-24
7. jkf-daily-r1-06 · case report
   A 30-year-old man from the Philippines with pollen allergy noted the appearance of oral allergy syndrome (OAS) after eating raw apple, raw peach, raw celery, and recently, jackfruit (Artocarpus integrifolia), a tropical fruit which belongs to the Moraceae family (mulberry) and to the genus Artocarpus (breadfruit tree). ... in RAST-inhibition studies neither rBet v 1 nor rBet v 2 (profilin), the well-known cross-reacting allergenic components in OAS, could inhibit the specific IgE response to jackfruit.
   Allergy, 1997 · checked 2026-09-24
8. jkf-daily-r1-04 · retrospective cohort study
   In the study group, six patients out of 37, and 20 patients out of 50 in the control group, developed CIL. They received 38 and 105 vials of filgrastim respectively.
   Biomolecules, 2020 · checked 2026-09-24