Bitter melon earned the nickname "plant insulin" because of compounds such as charantin, polypeptide-p and vicine. Cell and animal experiments show them increasing glucose uptake.
Humans are the problem. A Cochrane review pooling randomised trials in type 2 diabetes concluded that evidence for glycaemic control is insufficient. This is an ingredient where expectation and evidence sit far apart, and that is worth knowing first.
Key benefits
A plausible mechanism for blood sugar exists
Charantin and polypeptide-p have been observed promoting glucose transporter translocation. But human trials have not consistently shown clinically meaningful glucose lowering. It cannot replace diabetes medication.
Very high in vitamin C
84 mg per 100 g, more than lemon, at just 17 kcal. This is why bitter melon is worth eating regardless of the blood sugar story.
Dense in fibre for the calories
2.8 g per 100 g. At 17 kcal that is a very high ratio, which helps with fullness.
Rich in folate
72 µg per 100 g puts it near the top among vegetables. Folate is needed for cell division and red blood cell formation.
How to eat it well
- To cut the bitterness, remove the seeds and white pith, then salt it and squeeze out the liquid.
- Slicing thin and soaking in cold water removes more bitterness — along with water-soluble compounds.
- Stir-frying with egg or tofu lets fat and protein temper the bitterness. Okinawan stir-fry works on this principle.
- Bitter melon tea loses most of its vitamin C in drying. Eating it fresh is nutritionally better.
- If your interest is blood sugar, eat it as food — but do not treat it as grounds for adjusting medication.
What to watch out for
- Combined with diabetes medication, large amounts risk hypoglycaemia. If you take such drugs, monitor your glucose closely.
- Avoid it in pregnancy. The seeds and fruit contain compounds that may stimulate uterine contraction, and it has traditionally been contraindicated.
- The red aril around the seeds can cause vomiting and diarrhoea in children. Remove it.
- With G6PD deficiency, bitter melon seeds can trigger haemolysis.
- Concentrated bitter melon extracts have been linked to raised liver enzymes in some reports.
Nutrition
Approximate values per 100 g edible portion.
- Calories
- 17 kcal
- Carbohydrates
- 3.7 g
- Fiber
- 2.8 g
- Protein
- 1.0 g
- Vitamin C
- 84 mg
- Folate
- 72 µg
- Potassium
- 296 mg
- Magnesium
- 17 mg
Key nutrients
- Vitamin C
- Folate
- Fiber
- Potassium
- Vitamin A