Benefits
Visceral fat reduction on CT scans in overweight adults
In a 12-week placebo-controlled trial in 63 overweight adults, 200 mg a day left visceral (belly) fat area about 6 cm² lower than placebo (p = 0.048). Total and subcutaneous fat, body weight and waist size did not differ. The maker funded the trial and employed most authors. In a 12-week trial in young women, weight rose on placebo but not on Oligonol, yet end-of-study weight did not differ between groups.
Lipid peroxidation marker (MDA) after hard exertion
In a single small trial, a crossover in 10 healthy young men, one 200 mg dose before a maximal treadmill test meant malondialdehyde (MDA), an oxidative stress marker, was 8% below its starting level 30 minutes later vs 27% above on placebo. Absolute MDA did not differ, a 5-day course did not reach significance, and performance was unchanged.
Inflammation markers (prostaglandin E2, COX-2) after heat stress
In a small trial, 17 healthy young men drank 100 mg of Oligonol or a placebo drink before 30 minutes in hot water. Blood prostaglandin E2 rose 13% vs 30% on placebo and COX-2 rose 16% vs 22%, and core temperature rose slightly less. These are blood markers; two small studies of cytokines reported within-group or untested changes.
Anaerobic threshold during treadmill testing
In a 30-day trial in 59 regularly exercising men, 200 mg a day raised the anaerobic threshold by 7.4%, and its change differed across the Oligonol, vitamin C plus E and placebo groups. The primary result, running time to exhaustion, was null (p = 0.33), and a separate 10-man study found no change in maximal exercise performance.
Mid-thigh muscle area and walking speed in older adults
In a 12-week placebo-controlled trial in 103 adults averaging 64 years, men taking 200 mg a day kept their mid-thigh muscle area while men on placebo lost some (p = 0.03); this is a single trial, and the result was seen in men only. Gains in walking speed and grip were reported as changes within the Oligonol groups, separately for men and women, rather than as differences from placebo.
Finger skin temperature after a cold-water test
In a 14-day trial in 25 adults who felt unusually cold, 8 of them on 150 mg a day of Oligonol, finger skin temperature on day 14 was higher than on placebo. Finger blood flow rose from day 1 but was not reported as higher than placebo on day 14, and cold-sensation scores improved within groups without a reported difference from placebo. The maker funded the study.
Liver fat studied over 24 weeks
In a 24-week placebo-controlled trial in 38 adults with fatty liver disease, 100 mg twice daily lowered liver fat on MRI within the Oligonol group, but the difference from placebo was not statistically significant. The trial's main goal, a 30% or greater drop in liver fat, was reached by 20% vs 15% on placebo (p = 0.50).
Mechanism of action
Smaller polyphenol units from lychee and tea
Oligonol is made by oligomerizing lychee fruit polyphenols under acidic conditions with tea catechins, which raises the share of monomers (15.7%) and dimers (13.3%) compared with lychee fruit polyphenol (6.4% and 9.9%). The maker describes this as improving absorption; the trials described on this page did not compare it with plain lychee extract in people.
Proposed fat-breakdown pathway
The authors of the visceral fat trial point to laboratory work in which Oligonol raised PPAR-alpha, a regulator of fat burning in mitochondria, and lowered perilipin, a protein that shields stored fat from breakdown. These are cell and animal findings, not measured in the trial participants.
Lipid peroxidation (MDA) after exertion
Malondialdehyde (MDA) is a breakdown product of oxidized fats in the blood. In a small crossover study, its percent change from before to 30 minutes after a maximal treadmill test was lower after one 200 mg dose than after placebo.
Prostaglandin E2 and COX-2 signaling
COX-2 is an enzyme that makes prostaglandin E2, a messenger involved in fever and inflammation. After a hot-water immersion, both rose less in the blood of men who had taken Oligonol than after a placebo drink, alongside a slightly smaller rise in core temperature.
Clinical trials
Randomized, double-blind, placebo-controlled, parallel-group trial (UMIN000048004) of 200 mg Oligonol a day (100 mg after breakfast and dinner) vs dextrin for 12 weeks. Funded by Amino Up; six of seven authors were Amino Up employees. Body weight, BMI and waist size did not differ between groups. (Takanari et al. 2025, J Nutr Sci Vitaminol (Tokyo))
63 Japanese adults with a BMI of 25 to under 30 analyzed (31 on Oligonol, 32 on placebo), average age about 49.
The primary endpoint, visceral fat area on CT at 12 weeks, was about 6 cm² lower on Oligonol than on placebo after adjusting for baseline (p = 0.048); it went from 98.2 to 95.1 cm² on Oligonol and from 95.4 to 98.6 cm² on placebo. Total and subcutaneous fat area did not differ. Adverse events were mild and judged unrelated.
Randomized, single-blind crossover with placebo, a single 200 mg dose and a 5-day 200 mg course in water, each before a maximal treadmill exercise test, with washouts of at least 2 weeks. Exercise performance did not differ among phases; blood lactate at 30 minutes was lower in both Oligonol phases (p = 0.005); creatine kinase was higher in the single-dose phase than placebo. Funded by the National Research Foundation of Korea. (Kim et al. 2026, Antioxidants (Basel))
10 healthy young men in Korea.
The percent change in malondialdehyde (MDA), an oxidative stress marker, from before the test to 30 minutes after was lower with the single dose than with placebo (-8.4% vs +26.8%, p = 0.007). Absolute MDA levels did not differ significantly from placebo (p = 0.059), and the 5-day course did not reach significance.
Controlled study of a beverage containing 100 mg Oligonol vs a placebo beverage taken before 30 minutes of half-body immersion in 42 °C water in a climate chamber. Tympanic temperature rose about 0.17 °C less with Oligonol. Blood markers only; funding and product source are not stated in the abstract. (Shin et al. 2013, J Med Food)
17 healthy young men in Korea, average age 21.6.
Compared with the placebo drink, serum prostaglandin E2 rose 13.3% vs 29.6% and COX-2 rose 15.6% vs 21.8% immediately after the hot-water immersion (both p < 0.05). These are markers of inflammation signaling, not a measured health outcome.
Randomized, double-blind, three-arm trial (NCT00731926) of 200 mg Oligonol a day, vitamin C 800 mg plus vitamin E 320 IU, or placebo for 30 days; 59 of 70 randomized men analyzed after 11 were excluded for BMI above 25. Plasma free radical levels were similar across groups. Supported by an independent research fund from Amino Up, which supplied the products. (Kang et al. 2012, J Clin Biochem Nutr)
59 regularly exercising men in Korea, mostly in their mid-twenties.
The primary outcome, submaximal running time to exhaustion, did not differ between groups (adjusted change 3.87 min on Oligonol vs 1.60 min on placebo, p = 0.33). The anaerobic threshold rose 7.4% on Oligonol, and its change differed across the three groups (p = 0.03).
Randomized, double-blind, placebo-controlled trial of Oligonol, a processed litchi-derived polyphenol product from Amino Up, 100 mg twice daily for 24 weeks. The companion report found its secondary outcomes (weight, waist, ALT, fasting blood sugar, lipids) similar between groups. (Jinato et al. 2022, Nutrients)
38 adults in Thailand with fatty liver disease (liver fat of at least 11% on MRI), 19 per group.
Liver fat on MRI fell significantly within the Oligonol group but not within the placebo group; the difference between groups at week 24 was not statistically significant (p = 0.223 in the text, 0.215 in the table). A companion report of the same registered trial (TCTR20200814001; Chayanupatkul et al. 2022, J Integr Complement Med) found its primary endpoint, a 30% or greater drop in liver fat, was reached by 20% on Oligonol vs 15% on placebo (p = 0.50). Some gut bacteria differed between groups.