Home Ingredients GG-Gold® (Annatto-Derived Geranylgeraniol — American River Nutrition)
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GG-Gold® (Annatto-Derived Geranylgeraniol — American River Nutrition)

Bixa orellana
Evidence Level
Limited
3 Clinical Trials
6 Documented Benefits
2/5 Evidence Score

GG-Gold is American River Nutrition's trans-geranylgeraniol (GG) extracted from annatto seeds. The body also makes GG on the pathway that produces cholesterol and CoQ10. Three published human trials, all funded by sellers of GG, are cited here. In a placebo-controlled trial of GG-Gold in 66 adults (150 mg, then 300 mg a day for 8 weeks), testosterone did not change versus placebo overall; a rise in men who started below 700 ng/dL came from an exploratory analysis. Two trials used Annatto-GG 300, whose retail listing says it features GG-Gold: a crossover trial found no overall change in testosterone, and a 150-person randomized trial found that GG alone did not raise blood CoQ10 more than placebo. Claims about statin-related muscle symptoms rest on cell and animal research. A 90-day rat study found forestomach effects at every dose tested and liver effects at the two higher doses.

Studied Dose The GG-Gold trial gave 150 mg a day for 4 weeks, then 300 mg a day for 4 weeks. Two Annatto-GG 300 trials used 300 mg a day for 8 weeks; one arm took 120 mg GG with 200 mg ubiquinol. A trade report lists GRAS food uses at servings up to 250 mg. One case report used 600 mg a day.
Active Compound Annatto (Bixa orellana) seed-derived trans-geranylgeraniol (GG). In the published GG-Gold trial, each active softgel gave 150 mg of GG from 210 mg of GG-Gold. Annatto-GG 300, whose retail listing says it features GG-Gold, lists 300 mg of trans-geranylgeraniol per softgel with medium-chain triglycerides.

Benefits

Testosterone levels compared with placebo

In a randomized trial of GG-Gold funded by its maker, there was no significant change in testosterone versus placebo in men or women overall. In an exploratory group of 28 men starting below 700 ng/dL, it rose with GG and fell with placebo from baseline to week 8, but analyses including week 4 found no difference. A second brand-funded trial found no overall change.

Supported by Trial 1, Trial 2

Blood CoQ10 levels compared with placebo and CoQ10 products

In a randomized, double-blind trial of 150 healthy adults funded by the brand that sells the product, 300 mg a day of GG alone for 8 weeks did not raise plasma CoQ10 more than placebo. Ubiquinone and ubiquinol did, and adding 120 mg GG to ubiquinol gave no significant extra rise over ubiquinol alone.

Supported by Trial 3, Trial 1

Vitamin K2 (MK-4) side chain building block

Geranylgeraniol matches the side chain of MK-4, a form of vitamin K2, and in a cell study both compounds reduced the formation of bone-resorbing cells by different routes. No human study has shown that taking GG raises MK-4 or changes bone or artery measures.

Supported by Trial 2, Trial 3

Muscle cells exposed to statins: laboratory research

In rat and human muscle cell cultures, adding geranylgeraniol prevented statin-induced cell death, pointing to blocked protein prenylation rather than lower CoQ10 as one cause. No published human trial has tested GG for muscle symptoms in people taking statins, and anyone with such symptoms should speak with their prescriber rather than change a medicine.

Supported by Trial 2, Trial 3

Bone cell research and bisphosphonate interaction

In a review of 29 cell and animal studies, geranylgeraniol protected bone cells exposed to nitrogen-containing bisphosphonates and improved bone structure in obese mice, but it can also counteract these drugs, which the reviewers say limits taking them together. Four of the five reviewers have had research grants from the GG-Gold maker. The review included no human studies.

Supported by Trial 3, Trial 1

Muscle fiber size in animal research

In mice whose leg muscle nerve was cut, geranylgeraniol given by mouth reduced the shrinkage of muscle fibers and lowered a muscle breakdown protein. This is animal evidence; no study has shown that GG changes muscle size, strength or recovery in people.

Supported by Trial 2, Trial 3

Mechanism of action

1

Testosterone production in testis-derived cells

In testis-derived tumor cells grown in a dish, geranylgeraniol raised testosterone and progesterone output by activating adenylate cyclase and cAMP and PKA signaling. This has not been shown in people, and neither human trial that measured it found an overall change in testosterone.

2

CoQ10 mevalonate pathway precursor

GG is an intermediate of the mevalonate pathway, the same pathway that produces cholesterol and CoQ10. Statins suppress this pathway, which lowers the body's own supply of GG. In a randomized human trial, taking GG by mouth did not raise blood CoQ10 more than placebo.

3

Protein prenylation

GG-derived groups are attached to certain proteins (geranylgeranylation) so they can anchor to cell membranes and work. In muscle cell cultures, blocking this step caused cell death and adding geranylgeraniol prevented it. Whether supplemental GG changes prenylation in human tissue has not been measured.

4

Vitamin K2 (MK-4) side chain

Geranylgeraniol corresponds to the side chain of MK-4 (menaquinone-4). In bone cell co-cultures it reduced osteoclast formation by lowering RANKL, a different route from MK-4. Studies of MK-4 itself are evidence for vitamin K2, not for GG.

5

Inflammation and pain: not tested in people

A review of laboratory research describes anti-inflammatory activity of geranylgeraniol in cell and animal work. No human study cited on this page measured inflammation or pain.

Clinical trials

1
GG-Gold 150 then 300 mg/day vs Placebo: 8-Week Randomized Trial in Adults Aged 30 to 49
PubMed

Randomized, double-blind, placebo-controlled parallel trial (NCT05258513) of GG-Gold softgels: 150 mg of GG a day for 4 weeks, then 300 mg a day for 4 weeks; the placebo contained olive oil. Funded by American River Nutrition, the GG-Gold maker, through the authors' institute; the authors report no personal ties to the company. Blood safety panels and sex hormones were the outcomes; the testosterone subgroup with a 700 ng/dL cutoff was exploratory. Not PubMed-indexed. (Gheith et al. 2023, Nutraceuticals)

83 healthy adults aged 30 to 49 randomized; 66 completed (34 GG, 32 placebo).

Blood counts, the comprehensive metabolic panel and sex hormones showed no significant group by time differences in men or women. In an exploratory subgroup of men starting below 700 ng/dL (15 GG, 13 placebo), models using all three time points or weeks 4 to 8 found no effects; comparing only baseline with week 8, total testosterone rose 33.93 ng/dL with GG and fell 38.31 ng/dL with placebo (difference p = 0.040), with similar differences in free and bioavailable testosterone. 13 adverse events (7 GG, 6 placebo), none serious.

2
Geranylgeraniol 300 mg/day: 18-Week Placebo-First Crossover in Adults Aged 40 to 65
PubMed

Single-group, single-blind crossover: everyone took an MCT oil placebo for 8 weeks, then a 2-week washout, then Annatto-GG 300 (whose retail listing says it features GG-Gold) for 8 weeks, so order and time effects were not controlled. Funded by Designs for Health; the first author is employed by the sponsor and a second author sits on its scientific advisory board. Registered as NCT06747624. The testosterone subgroup with a 600 ng/dL cutoff was exploratory. (Jurgelewicz et al. 2026, Integr Med (Encinitas))

38 healthy adults aged 40 to 65 enrolled; 34 completed (14 men, 20 women).

Total testosterone, free testosterone and SHBG did not change significantly in the full sample or in women (all P > .05). In 8 men starting below 600 ng/dL, total testosterone rose 28.44 ng/dL during the GG phase (P = .015); in the same men it changed by 14.63 ng/dL downward during placebo (P = .471), and no direct comparison between the phases was reported. Serum CoQ10 fell during placebo and did not change during GG. Questionnaire scores did not change. 3 mild adverse events during GG and 2 during placebo; none serious.

3
Geranylgeraniol 300 mg/day vs Placebo and CoQ10 Products: 8-Week Randomized Trial
PubMed

Randomized, double-blind, placebo-controlled parallel trial with five arms (ubiquinone, ubiquinol, Annatto-GG 300, whose retail listing says it features GG-Gold; ubiquinol plus 120 mg GG; placebo), registered as NCT06640465. Funded by Designs for Health, which sells the GG products; the first author sits on its scientific advisory board. Secondary outcomes included vitality, vigor and global health questionnaires. (D'Adamo et al. 2026, J Nutr Metab)

150 healthy adults aged 40 or older (mean age 52.1) randomized to five arms; statin users in the past 6 months were excluded.

Plasma CoQ10, the primary outcome, did not differ between GG alone and placebo, or between ubiquinol and ubiquinol plus GG (p >= 0.15). Ubiquinone, ubiquinol and ubiquinol plus GG raised CoQ10 more than placebo. Questionnaire scores did not differ from placebo. One person in the GG arm had digestive upset and dropped out; no serious adverse events.

Side effects and drug interactions

Common Potential side effects

In a 66-person randomized trial of GG-Gold (150 mg a day for 4 weeks, then 300 mg), blood counts and a comprehensive metabolic panel did not change differently from placebo over 8 weeks. 7 adverse events were reported with GG (including 2 nosebleeds, 2 reports of fatigue and 2 of increased acne) and 6 with placebo; none were serious.
In a 34-person crossover trial at 300 mg a day for 8 weeks, 3 participants reported mild adverse events during the GG phase and 2 during placebo; none were serious. That trial measured hormones and CoQ10, not routine safety blood work.
In a 150-person randomized trial, one person taking 300 mg a day of GG reported digestive upset and left the study; there were no serious adverse events in any arm, and the authors reported no harmful changes in liver or kidney markers over 8 weeks.
Animal toxicology: in a 90-day rat study of an annatto oil with about 80% trans-GG, given by stomach tube at 725, 1450 and 2900 mg/kg body weight a day, the authors found treatment-related adverse effects in the forestomach at all doses and in the liver at the two higher doses. They set 725 mg/kg a day as the lowest observed adverse effect level for local effects and the no observed adverse effect level for systemic effects. Lab tests found no evidence of mutagenicity or genotoxic activity.
The maker's GRAS status is self-affirmed: a trade report describes it as the company's own determination, based on an expert panel convened by the consulting firm AIBMR Life Sciences, and does not describe an FDA review.
Long-term safety in people has not been studied. All three human trials gave GG for 8 weeks, and the fact that the body makes GG itself does not show that supplemental doses are harmless over years.
Pregnancy and lactation: no human data; the trials excluded people who were pregnant, breastfeeding or planning pregnancy. Speak with a clinician before use.

Important Drug interactions

Statins: no human trial has tested GG in people taking statins (the CoQ10 trial excluded recent statin users), and a trial in people with statin-related muscle symptoms is still listed as recruiting. Do not use GG to manage statin side effects or change your statin; talk to your prescriber about muscle symptoms.
Bisphosphonates: in cell studies geranylgeraniol counteracted the action of nitrogen-containing bisphosphonates on bone cells, and a review of this research states that this limits taking the two together. Anyone on these osteoporosis medicines should ask their prescriber before using GG.
Testosterone therapy: GG produced no overall change in testosterone versus placebo in the GG-Gold trial, which excluded people on hormone replacement, so any added effect is speculative. Anyone on hormone therapy should be guided by their doctor.
Anticoagulants and antiplatelet drugs: no study has tested GG together with these medicines; the GG-Gold trial excluded people taking them, and 2 people taking GG (none on placebo) reported nosebleeds. Anyone taking a blood thinner should ask their prescriber before starting.
CoQ10 supplements: no known interaction. In a randomized trial, GG alone did not raise blood CoQ10, and adding GG to ubiquinol gave no significant extra rise, so GG is not a substitute for CoQ10.
Vitamin K2 supplements: no known interaction. GG has not been shown to raise MK-4 levels in people, so it is not a substitute for vitamin K2.

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Frequently asked questions about GG-Gold® (Annatto-Derived Geranylgeraniol — American River Nutrition)

What is GG-Gold used for?

GG-Gold is American River Nutrition's geranylgeraniol from annatto seeds. Designs for Health's Annatto-GG 300, whose retail listing says it features GG-Gold, is described there as supporting CoQ10 production, muscle and bone function, steroid hormone regulation and energy production. In the three published human trials, all funded by companies that sell GG, it did not change testosterone overall and GG alone did not raise blood CoQ10 more than placebo.

Does GG-Gold raise testosterone?

Not overall. In a randomized trial of GG-Gold in 66 adults, testosterone did not change versus placebo in men or women. In an exploratory analysis of 28 men starting below 700 ng/dL, testosterone rose with GG and fell with placebo from baseline to week 8, but not in analyses that included week 4. In a second, placebo-first trial of 300 mg a day, testosterone did not change overall; a rise in 8 men was not compared with the placebo phase.

Does geranylgeraniol help the body make more CoQ10?

GG sits on the pathway the body uses to make CoQ10, but in a randomized, double-blind trial of 150 adults, 300 mg a day of GG alone for 8 weeks did not raise plasma CoQ10 more than placebo, while ubiquinone and ubiquinol did. Adding GG to ubiquinol gave no significant extra rise over ubiquinol alone.

Is GG-Gold safe, and does it have side effects?

Human data come from three 8-week trials at 150 to 300 mg a day: blood counts and a metabolic panel did not change versus placebo in one, and adverse events were few and mild, such as digestive upset, acne, fatigue and nosebleeds, with none serious. In a 90-day rat study, an annatto GG oil caused forestomach effects at every dose tested and liver effects at the two higher doses. Long-term human safety is unknown. People on statins, bisphosphonates or blood thinners, or who are pregnant or breastfeeding, should ask a clinician first.

What is GG-Gold?

GG-Gold is American River Nutrition's trans-geranylgeraniol (GG) extracted from annatto seeds. The body also makes GG on the pathway that produces cholesterol and CoQ10. Three published human trials, all funded by sellers of GG, are cited here.

What is the recommended dosage of GG-Gold?

The clinically studied dose is The GG-Gold trial gave 150 mg a day for 4 weeks, then 300 mg a day for 4 weeks. Two Annatto-GG 300 trials used 300 mg a day for 8 weeks; one arm took 120 mg GG with 200 mg ubiquinol. A trade report lists GRAS food uses at servings up to 250 mg. Always follow the product label and check with a healthcare provider for personal advice.

Does GG-Gold interact with any medications?

Possible interactions include: Statins: no human trial has tested GG in people taking statins (the CoQ10 trial excluded recent statin users), and a trial in people with statin-related muscle symptoms is still listed as recruiting. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for GG-Gold?

NutraSmarts rates the evidence for GG-Gold as Limited (2 out of 5). It is backed by 3 study summaries and 14 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(14 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. Gheith R, Sharp M, Stefan M, Ottinger C, Lowery R, Wilson J. The Effects of Geranylgeraniol on Blood Safety and Sex Hormone Profiles in Healthy Adults: A Dose-Escalation, Randomized, Placebo-Controlled Trial Nutraceuticals. 2023;3(4):605-618. doi: 10.3390/nutraceuticals3040043.SourceUsed to support: Not PubMed-indexed (MDPI journal; full text read). Randomized, double-blind, placebo-controlled parallel trial (NCT05258513) at the Applied Science and Performance Institute, funded by American River Nutrition; the authors report no personal relationship with the company. 83 healthy adults aged 30 to 49 were randomized and 66 completed (34 GG, 32 placebo). The GG group took GG-Gold softgels giving 150 mg of GG a day (from 210 mg GG-Gold) for 4 weeks, then 300 mg a day for 4 weeks; placebo softgels contained olive oil. There were no significant group by time interactions for blood counts, the comprehensive metabolic panel or male or female sex hormones. In an exploratory subgroup of men with baseline total testosterone below 700 ng/dL (15 GG, 13 placebo), models using all three time points or weeks 4 to 8 showed no significant effects; comparing baseline with week 8 only, total (+7.5% vs minus 8.0%, p = 0.040), free (p = 0.036) and bioavailable testosterone (p = 0.034) changed differently between groups. 13 adverse events (7 GG, 6 placebo), none serious; people taking anticoagulant, antiplatelet or hormone therapies were excluded.
  2. Jurgelewicz M, D'Adamo CR, Malaya CA. The Effects of Geranylgeraniol Supplementation on Testosterone in Middle-Aged Healthy Adults: An 18-Week, Single-Group Crossover Placebo-Controlled Trial. Integr Med (Encinitas). 2026;25(2):12-19.PubMedUsed to support: Single-group crossover trial funded by Designs for Health, whose employee is the first author (a second author sits on its scientific advisory board). 38 adults aged 40 to 65 enrolled and 34 finished (14 men, 20 women). Everyone took an MCT oil placebo for 8 weeks, then had a 2-week washout, then took 300 mg a day of Annatto-GG 300 for 8 weeks, single-blind. Total testosterone, free testosterone and SHBG did not change significantly in the full sample or in women (all P > .05). In an exploratory subgroup of 8 men with baseline total testosterone below 600 ng/dL, total testosterone rose 28.44 ng/dL during the GG phase (P = .015); no direct test against the placebo phase was reported. Serum CoQ10 fell during placebo and did not change during GG. Health and sexual function questionnaires did not change. 5 participants reported mild adverse events (3 during GG, 2 during placebo); none were serious.
  3. D'Adamo CR, Leary M, Mote C, Ackerman R, Holthouse M, Binstock B, Adair E, Piedrahita G, Wehage S, Burke K. A Randomized, Double-Blind, Placebo-Controlled Trial Comparing the Effects of Commercially Available Ubiquinone, Ubiquinol, and Geranylgeraniol Dietary Supplements on Plasma CoQ10 Concentrations. J Nutr Metab. 2026;2026:5589963. doi: 10.1155/jnme/5589963.PubMedUsed to support: Randomized, double-blind, placebo-controlled parallel trial in 150 healthy adults (mean age 52.1) funded by Designs for Health; the first author sits on its scientific advisory board. For 8 weeks, arms took one capsule a day of ubiquinone (200 mg), ubiquinol (200 mg), Annatto-GG 300 (300 mg GG), a ubiquinol plus GG product (200 mg ubiquinol and 120 mg GG) or placebo. The primary outcome, plasma CoQ10, did not differ between GG alone and placebo, or between ubiquinol and ubiquinol plus GG (p >= 0.15); ubiquinone, ubiquinol and ubiquinol plus GG raised CoQ10 more than placebo. Vitality, vigor and global health questionnaires did not differ from placebo. One person in the GG arm reported digestive upset and dropped out; there were no serious adverse events.
  4. Preece K, Glávits R, Foster JR, Murbach T, Endres JR, Hirka G, Vértesi A, Béres E, Szakonyiné IP. A toxicological evaluation of geranylgeraniol. Regul Toxicol Pharmacol. 2021;124:104975. doi: 10.1016/j.yrtph.2021.104975.PubMedUsed to support: Toxicology study of a molecularly distilled, food grade annatto oil containing about 80% trans-geranylgeraniol. Bacterial reverse mutation, in vitro chromosomal aberration and in vivo micronucleus tests found no evidence of mutagenicity or genotoxic activity. In a 90-day study, rats were given 0, 725, 1450 or 2900 mg/kg body weight a day by gavage; treatment-related adverse effects were seen in the forestomach at all doses and in the liver at the intermediate and high doses. The authors set 725 mg/kg a day as the lowest observed adverse effect level for local effects and the no observed adverse effect level for systemic effects. Three authors are from AIBMR Life Sciences, the consulting firm that a trade report says convened GG-Gold's GRAS panel, five from the contract lab Toxi-Coop and one from ToxPath Sciences; the abstract does not state who funded the study or name the test material's supplier. Animal data, not human data.
  5. Johnson TE, Zhang X, Bleicher KB, Dysart G, Loughlin AF, Schaefer WH, Umbenhauer DR. Statins induce apoptosis in rat and human myotube cultures by inhibiting protein geranylgeranylation but not ubiquinone. Toxicol Appl Pharmacol. 2004;200(3):237-50. doi: 10.1016/j.taap.2004.04.010.PubMedUsed to support: Cell culture study from Merck Research Laboratories: in rat and human muscle cell (myotube) cultures, statin-induced cell death was completely prevented by mevalonate or geranylgeraniol but not by farnesol, and ubiquinone (CoQ10) levels did not track with cell death. The authors conclude statins cause this cell death in part by blocking protein geranylgeranylation. In rat liver cells, geranylgeraniol did not lessen statin toxicity. Laboratory evidence only; no supplement was tested in people.
  6. Hiruma Y, Nakahama K, Fujita H, Morita I. Vitamin K2 and geranylgeraniol, its side chain component, inhibited osteoclast formation in a different manner. Biochem Biophys Res Commun. 2004;314(1):24-30. doi: 10.1016/j.bbrc.2003.12.051.PubMedUsed to support: Cell co-culture study: vitamin K2 (MK-4) and geranylgeraniol, which the authors describe as its side chain component, both reduced osteoclast formation, but by different routes (geranylgeraniol by lowering RANKL expression). Geranylgeraniol also abolished the disruption of osteoclast actin rings caused by a nitrogen-containing bisphosphonate, while MK-4 did not. Laboratory evidence only.
  7. Ho HJ, Shirakawa H, Giriwono PE, Ito A, Komai M. A novel function of geranylgeraniol in regulating testosterone production. Biosci Biotechnol Biochem. 2018;82(6):956-962. doi: 10.1080/09168451.2017.1415129.PubMedUsed to support: Review by a university group summarizing laboratory work in which geranylgeraniol raised testosterone and progesterone production in testis-derived I-10 tumor cells by activating adenylate cyclase through cAMP and PKA signaling. Cell evidence only; it does not show an effect of a supplement in people.
  8. Ekeuku SO, Al Salman MFA, Mohamad NV, Wong SK, Chin KY. Geranylgeraniol as a Modulator of Mevalonate Pathway Disruption: A Scoping Review of Cellular Mechanisms and Skeletal Outcomes in Osteoporosis Models. Pharmaceuticals (Basel). 2026;19(7):1117. doi: 10.3390/ph19071117.PubMedUsed to support: Scoping review of 29 cell and animal studies. Geranylgeraniol restored protein prenylation and bone cell survival in cells exposed to nitrogen-containing bisphosphonates, and dietary geranylgeraniol improved bone structure measures in obese mice. Because it can counteract the action of these drugs, the reviewers state that its capacity to antagonize them limits taking the two together, and that human exposure and dosing studies are needed. Four of the five reviewers declared research grants from American River Nutrition, the maker of GG-Gold, for GGOH studies. No human studies were included.
  9. Miyawaki A, Rojasawasthien T, Hitomi S, Aoki Y, Urata M, Inoue A, Matsubara T, Morikawa K, Habu M, Tominaga K, Kokabu S. Oral Administration of Geranylgeraniol Rescues Denervation-induced Muscle Atrophy via Suppression of Atrogin-1. In Vivo. 2020;34(5):2345-2351. doi: 10.21873/invivo.12047.PubMedUsed to support: Mouse study: geranylgeraniol given by mouth reduced the loss of muscle fiber cross-sectional area and lowered Atrogin-1, a muscle breakdown protein, after the muscle's nerve was cut; it also limited steroid-induced fiber shrinkage in cultured cells. One author is employed by Mitsubishi-Chemical Foods Corporation. Animal and cell evidence only.
  10. Tan B, Chin KY. Potential role of geranylgeraniol in managing statin-associated muscle symptoms: a COVID-19 related perspective. Front Physiol. 2023;14:1246589. doi: 10.3389/fphys.2023.1246589.PubMedUsed to support: Opinion article proposing geranylgeraniol for statin-associated muscle symptoms, written by the president of American River Nutrition (the maker of GG-Gold) with a university co-author. It reports no new human data. Listed as the maker's position, not as evidence of benefit.
  11. LaGrutta A, Arnold D, Coetzee O. Boosting Testosterone Naturally in Hashimoto's: A Case Report on Trans-Geranylgeraniol Supplementation. Altern Ther Health Med. 2025;31(5):52-57.PubMedUsed to support: Single case report of one 27-year-old man with autoimmune thyroid disease and low testosterone who took 600 mg a day of trans-geranylgeraniol (Annatto-GG 300) for nine weeks, added to earlier diet changes and other supplements; the authors report a rise in testosterone. A single uncontrolled case with several simultaneous treatments cannot show what caused the change. Not used as trial evidence.
  12. Designs for Health, Inc. (product listing on Fullscript) Annatto-GG 300 Fullscript product catalog. 2026;Product listing, accessed October 2026..SourceUsed to support: Not PubMed-indexed. Retail listing for Designs for Health's Annatto-GG 300, the product named in two published human trials: the listing states the product features GG-Gold, a patented form of GG extracted from annatto seeds, and lists 300 mg of trans-geranylgeraniol per softgel with medium-chain triglycerides, one softgel a day. The trial papers themselves name only Annatto-GG 300.
  13. Montemarano M. American River Nutrition Affirms GRAS Status of Geranylgeraniol Ingredient Nutraceuticals World. 2021;Published July 7, 2021..SourceUsed to support: Not PubMed-indexed. Trade press report that American River Nutrition achieved self-confirmed GRAS status for GG-Gold through an expert panel convened by the consulting firm AIBMR Life Sciences, and that GG-Gold is available for use at servings of up to 250 mg in nutrition bars, sports drinks, powders and chocolate. The report describes the company's own determination, not an FDA review.
  14. Texas Tech University Health Sciences Center (ClinicalTrials.gov record). Effect of Annatto-derived Geranylgeraniol (GG) on Statin-associated Myopathy ClinicalTrials.gov. 2026;NCT05312424. Record last updated September 2026, accessed October 2026..SourceUsed to support: Not PubMed-indexed. Registry record of a placebo-controlled trial comparing olive oil placebo, 150 mg and 300 mg a day of annatto-derived GG in statin-associated muscle symptoms, sponsored by Texas Tech University Health Sciences Center. Status: recruiting, with primary completion estimated for June 2027; no results posted.