Salacia reticulata (Kothala Himbutu)

Salacia reticulata Wight (closely related: Salacia oblonga, Salacia chinensis)
Evidence Level
Moderate
3 Clinical Trials
5 Documented Benefits
3/5 Evidence Score

Salacia reticulata, known in Sinhalese as Kothala Himbutu, is a woody vine native to Sri Lanka and southern India. Its root, root bark, and stem have been used for centuries in Ayurvedic medicine for diabetes and metabolic complaints. The plant contains a distinctive set of sulfonium-sulfate compounds, including salacinol, kotalanol, and de-O-sulfonated variants, which act as potent inhibitors of intestinal alpha-glucosidase enzymes that break down dietary carbohydrate. Acute postprandial glucose trials in healthy adults and patients with type 2 diabetes show that Salacia extracts blunt blood sugar and insulin rises after carbohydrate-rich meals, while longer 6- and 12-week interventions report improvements in fasting glucose, lipid profiles, and HbA1c in selected populations. The plant is closely related to Salacia oblonga and Salacia chinensis, which share alpha-glucosidase-inhibiting actives and have been studied in parallel Japanese and Western clinical programs.

Studied Dose Acute postprandial trials have used 240–1,000 mg of Salacia extract before high-carbohydrate meals; 6- to 12-week trials in prediabetes and type 2 diabetes have used 500 mg per day of standardized Salacia reticulata root or bark extracts.
Active Compound Sulfonium-sulfate inner salts salacinol and kotalanol, and their de-O-sulfonated counterparts neosalacinol and neokotalanol, together with mangiferin and salaprinol; potent intestinal alpha-glucosidase inhibitors.

Benefits

Helps blunt post-meal blood sugar spikes

Single doses of standardized Salacia extracts taken with carbohydrate-rich meals have been shown to reduce post-meal rises in blood glucose and insulin in healthy adults and patients with type 2 diabetes, supporting smoother glycemic responses after large or starchy meals.

Supports healthy fasting glucose

Six-week and longer trials of standardized Salacia reticulata root and bark extracts in adults with prediabetes and mild hyperlipidemia have shown reductions in fasting blood sugar versus placebo, supporting healthy fasting glucose maintenance alongside lifestyle measures.

Helps support healthy lipid balance

In adults with prediabetes and mild to moderate hyperlipidemia, Salacia reticulata extracts have been associated with reductions in LDL cholesterol versus placebo over 6 weeks, supporting a healthier overall lipid pattern as part of broader metabolic-support strategies.

Provides a complement to GLP-1-style dietary strategies

By slowing carbohydrate digestion in the upper small intestine, Salacia extracts can shift undigested carbohydrate distally and modulate gut hormone responses, complementing dietary approaches aimed at supporting incretin signaling and satiety.

Traditional Ayurvedic metabolic support

Kothala Himbutu has a long Ayurvedic and Sri Lankan history of use for sweet urine disease and metabolic complaints, supporting its continued framing as a traditional botanical for healthy weight and blood sugar maintenance within evidence-based supplement formulations.

Mechanism of action

1

Intestinal alpha-glucosidase inhibition

Salacinol, kotalanol, and their de-O-sulfonated forms inhibit alpha-glucosidase enzymes such as maltase, sucrase, and isomaltase at the intestinal brush border, slowing the breakdown of complex carbohydrates into absorbable monosaccharides and blunting postprandial glucose rises.

2

Modulation of incretin and gut microbiota

By delivering more carbohydrate to the distal small intestine and colon, Salacia extracts increase breath hydrogen and may modulate L-cell incretin secretion and gut microbiota composition, supporting incretin-related metabolic effects and changes in microbial fermentation.

3

Mangiferin and polyphenol contribution

Mangiferin and related polyphenols in Salacia species contribute antioxidant and PPAR-related signaling that may complement alpha-glucosidase inhibition, supporting effects on lipid handling and insulin sensitivity observed in longer-term clinical studies.

Clinical trials

1
Acute postprandial glycemia trial

Double-masked, randomized crossover trial of 500, 700, or 1,000 mg of Salacia oblonga extract with a standardized high-carbohydrate meal compared with no extract (Heacock et al., Journal of the American Dietetic Association).

Healthy adults in a crossover design.

The highest dose of Salacia extract reduced the postprandial plasma glucose incremental area under the curve by about 23 percent and serum insulin AUC by about 29 percent, with concurrent rises in breath hydrogen consistent with carbohydrate-malabsorption mechanism. Supports acute postprandial benefits of Salacia alpha-glucosidase inhibition.

2
Salacia reticulata 3-month crossover trial

Randomized, single-center, double-blind crossover study of an herbal preparation containing Salacia reticulata in type 2 diabetes over 3 months per phase (Jayawardena et al., Journal of Ethnopharmacology).

Adult patients with type 2 diabetes.

Salacia reticulata-containing herbal tea improved fasting and postprandial glycemia compared with placebo over 3 months, with reductions in HbA1c reported in the active arm. Provides among the earliest longer-term human evidence for Salacia reticulata as an adjunct in type 2 diabetes management.

3
Salacia oblonga acute trial in type 2 diabetes

Randomized, double-blind crossover trial of 240 mg or 480 mg of Salacia oblonga extract added to a high-carbohydrate liquid meal in patients with type 2 diabetes (Williams et al., American Journal of Clinical Nutrition).

66 patients with type 2 diabetes.

Both doses of Salacia oblonga significantly lowered the postprandial positive glucose area under the curve and the adjusted peak glucose response, with effects of about 14–22 percent reduction in glucose AUC across the two doses. Supports Salacia species as adjuncts for postprandial glucose control in type 2 diabetes.

Side effects and drug interactions

Common Potential side effects

Increased gas, bloating, or loose stools due to carbohydrate malabsorption are most common.
Mild stomach discomfort or borborygmi can occur with high-carbohydrate meals.
Hypoglycemia is rare unless combined with strong glucose-lowering medications.
Long-term safety data beyond 12 weeks are limited but generally favorable.
Pregnancy and breastfeeding safety has not been well established.

Important Drug interactions

Insulin and sulfonylureas: additive hypoglycemic risk; coordinate dosing with prescriber.
Acarbose and miglitol: overlapping alpha-glucosidase inhibition may increase gastrointestinal side effects.
Metformin: may have complementary metabolic effects; monitor blood sugar.
GLP-1 receptor agonists: combined use may amplify satiety and gastrointestinal effects.

Frequently asked questions about Salacia reticulata (Kothala Himbutu)

What is the recommended dosage of Salacia reticulata (Kothala Himbutu)?

The clinically studied dose for Salacia reticulata (Kothala Himbutu) is Acute postprandial trials have used 240–1,000 mg of Salacia extract before high-carbohydrate meals; 6- to 12-week trials in prediabetes and type 2 diabetes have used 500 mg per day of standardized Salacia reticulata root or bark extracts.. Always follow product labeling and consult a healthcare provider for personalized dosing recommendations.

What is Salacia reticulata (Kothala Himbutu) used for?

Salacia reticulata (Kothala Himbutu) is studied for helps blunt post-meal blood sugar spikes, supports healthy fasting glucose, helps support healthy lipid balance. Single doses of standardized Salacia extracts taken with carbohydrate-rich meals have been shown to reduce post-meal rises in blood glucose and insulin in healthy adults and patients with type 2 diabetes, supporting smoother glycemic responses after …

Are there side effects from taking Salacia reticulata (Kothala Himbutu)?

Reported potential side effects may include: Increased gas, bloating, or loose stools due to carbohydrate malabsorption are most common. Mild stomach discomfort or borborygmi can occur with high-carbohydrate meals. Always consult a healthcare provider before starting any new supplement, especially if you have underlying conditions or take medications.

Does Salacia reticulata (Kothala Himbutu) interact with medications?

Known drug interactions may include: Insulin and sulfonylureas: additive hypoglycemic risk; coordinate dosing with prescriber. Acarbose and miglitol: overlapping alpha-glucosidase inhibition may increase gastrointestinal side effects. Consult a pharmacist or healthcare provider if you take prescription medications.

Is Salacia reticulata (Kothala Himbutu) good for metabolic health?

Yes, Salacia reticulata (Kothala Himbutu) is researched for Metabolic Health support. In adults with prediabetes and mild to moderate hyperlipidemia, Salacia reticulata extracts have been associated with reductions in LDL cholesterol versus placebo over 6 weeks, supporting a healthier overall lipid pattern as part of broader metabolic-support strategies.

References(5 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Heacock PM, Hertzler SR, Williams JA, Wolf BW. Effects of a medical food containing an herbal alpha-glucosidase inhibitor on postprandial glycemia and insulinemia in healthy adults. Journal of the American Dietetic Association. 2005;J Am Diet Assoc. 2005 Jan;105(1):65-71..PubMedUsed to support: Crossover trial showing Salacia oblonga extract dose-dependently reduced postprandial glucose and insulin AUC in healthy adults.
  2. Jayawardena MH, de Alwis NM, Hettigoda V, Fernando DJ. A double blind randomised placebo controlled cross over study of a herbal preparation containing Salacia reticulata in the treatment of type 2 diabetes. Journal of Ethnopharmacology. 2005;J Ethnopharmacol. 2005 Feb 28;97(2):215-8..PubMedUsed to support: Three-month crossover RCT showing Salacia reticulata herbal preparation improved fasting and postprandial glycemia and HbA1c in type 2 diabetes.
  3. Williams JA, Choe YS, Noss MJ, Baumgartner CJ, Mustad VA. Extract of Salacia oblonga lowers acute glycemia in patients with type 2 diabetes. American Journal of Clinical Nutrition. 2007;Am J Clin Nutr. 2007 Jul;86(1):124-30..PubMedUsed to support: Crossover RCT in 66 patients with type 2 diabetes showing 240 mg and 480 mg Salacia oblonga extracts reduced postprandial glucose AUC and peak glucose responses.
  4. Shivaprasad HN, Bhanumathy M, Sushma G, Midhun T, Raveendra KR, Sushma KR, Venkateshwarlu K. Salacia reticulata improves serum lipid profiles and glycemic control in patients with prediabetes and mild to moderate hyperlipidemia: a double-blind, placebo-controlled, randomized trial. Journal of Medicinal Food. 2013;J Med Food. 2013 Jun;16(6):564-8..PubMedUsed to support: RCT in adults with prediabetes and mild hyperlipidemia showing Salacia reticulata root-bark extract reduced LDL cholesterol and fasting blood sugar versus placebo over 6 weeks.
  5. Kobayashi M, Akaki J, Ninomiya K, Yoshikawa M, Muraoka O, Morikawa T, Odawara M. Dose-Dependent Suppression of Postprandial Hyperglycemia and Improvement of Blood Glucose Parameters by Salacia chinensis Extract: Two Randomized, Double-Blind, Placebo-Controlled Studies. Journal of Medicinal Food. 2021;J Med Food. 2021 Jan;24(1):10-17..PubMedUsed to support: Two RCTs showing Salacia chinensis extract (related species) dose-dependently suppressed postprandial blood glucose and insulin responses and improved blood glucose parameters over 12 weeks.