Get Your Personalized Supplement StackSupplement Stack Quiz

Seed Extract

Also known as: Grape seed extract, GSE, Irvingia gabonensis seed extract, African mango seed extract, Flaxseed extract, Linum usitatissimum extract, Vitis vinifera seed extract

Overview

Seed extracts are concentrated preparations derived from the seeds of various plants, rich in bioactive compounds such as polyphenols, fatty acids, and fibers. This category encompasses several distinct extracts, each with unique properties and applications. Grape Seed Extract (GSE), primarily from Vitis vinifera, is rich in proanthocyanidins and is valued for its antioxidant and anti-inflammatory effects. Irvingia gabonensis seed extract, also known as African mango seed extract, is derived from the seeds of the Irvingia gabonensis tree and is primarily used for weight management and cardiovascular risk reduction. Flaxseed extract, from Linum usitatissimum, contains alpha-linolenic acid (ALA), lignans, and fiber, and is often used for cardiovascular health, particularly for modulating lipid profiles and inflammation. These extracts are generally classified as plant-derived dietary supplements, often targeting antioxidant support, weight management, or cardiovascular health. Research on these extracts is moderately mature, with multiple randomized controlled trials and meta-analyses supporting some benefits, though heterogeneity in study designs and outcomes exists.

Benefits

Grape Seed Extract (GSE) has demonstrated significant benefits in reducing oxidative stress markers and inflammation. Meta-analyses show a significant reduction in malondialdehyde (SMD: -1.04; 95% CI: -1.65, -0.42) and oxidized LDL (SMD: -0.44; 95% CI: -0.75, -0.13), along with decreased hs-CRP levels, particularly in adults with oxidative stress-related conditions. These effects are typically observed over weeks to months of supplementation. Irvingia gabonensis seed extract has shown statistically significant improvements in anthropometric measures in overweight and obese adults. Meta-analyses indicate reductions in body weight, BMI, and waist circumference, with benefits appearing over 4-12 weeks of supplementation. Flaxseed extract, while rich in ALA and lignans, has not consistently shown significant anti-inflammatory effects. A meta-analysis found no significant effect on plasma C-reactive protein (CRP) concentrations, with studies exhibiting high heterogeneity. Therefore, its benefits for inflammation reduction are less clear compared to its potential role in lipid metabolism.

How it works

The mechanisms of action for seed extracts vary by type. Grape Seed Extract (GSE) exerts its effects primarily through its rich polyphenol content, which acts as a potent antioxidant by scavenging free radicals, inhibiting lipid peroxidation, and downregulating inflammatory cytokines. Irvingia gabonensis seed extract is believed to modulate lipid metabolism, influence appetite regulation, and affect adipogenesis, contributing to its observed benefits in weight loss and improved cardiovascular markers. Flaxseed, rich in alpha-linolenic acid (ALA) and lignans, is thought to modulate inflammation and lipid metabolism, although its clinical effects on inflammation markers are inconsistent. GSE targets oxidative stress markers like malondialdehyde and inflammatory markers such as hs-CRP. Irvingia gabonensis may affect adipocyte function and lipid enzymes. Flaxseed lignans act as phytoestrogens and antioxidants. The bioavailability of polyphenols in GSE is moderate and influenced by gut microbiota. Irvingia gabonensis components are absorbed with variable bioavailability, while flaxseed ALA has low conversion efficiency to EPA/DHA.

Side effects

Seed extracts are generally well-tolerated at recommended doses, with no serious adverse events reported in clinical trials. Minor gastrointestinal discomfort, such as bloating or gas, is the most commonly reported side effect, particularly with flaxseed due to its fiber content. Mild allergic reactions are possible but rare. No significant rare adverse events have been documented in meta-analyses. Potential drug interactions exist, especially with anticoagulants, due to the presence of polyphenols in GSE and omega-3 fatty acids in flaxseed, which may affect blood clotting. Individuals with bleeding disorders or those on blood-thinning medications should exercise caution. There is limited data on the safety of seed extracts in pregnant or lactating women, so caution is advised for these populations. Overall, the safety profile is favorable, but awareness of potential interactions and minor side effects is important.

Dosage

Recommended dosages vary significantly among different seed extracts. For Grape Seed Extract (GSE), a minimum effective dose of approximately 100 mg/day of proanthocyanidins is suggested, with an optimal range of 100–300 mg/day of total polyphenols. Doses up to 600 mg/day have been studied. It is often recommended to take GSE with meals to improve absorption, and standardized extracts are preferred. For Irvingia gabonensis seed extract, a common effective dose is 150 mg twice daily, with an optimal range of 150–300 mg twice daily. There is no established maximum safe dose, but consistent daily dosing over several weeks is crucial for observing benefits. Extracts standardized for active compounds are recommended. For Flaxseed extract, a minimum effective dose is around 13 g of ground flaxseed per day, with a typical range of 13–60 g/day, whether as powder or oil. The maximum studied dose is up to 60 g/day. Due to its fiber content, it should be taken with meals. Ground flaxseed is generally preferred over whole flaxseed for better absorption of its beneficial compounds.

FAQs

Is seed extract supplementation safe?

Generally, yes. Seed extracts are well-tolerated, with minor gastrointestinal side effects possible. No serious adverse events have been reported in clinical trials.

How long before benefits appear?

Benefits for weight and cardiovascular markers typically appear after 4-12 weeks of consistent supplementation. Antioxidant effects may be observed earlier.

Can seed extracts replace medications?

No. Seed extracts may complement existing therapies but should not be used as a substitute for prescribed medications or medical advice.

Are all seed extracts the same?

No. The effects and benefits vary widely depending on the specific seed type, its bioactive compounds, and the preparation method of the extract.

Research Sources

https://pubmed.ncbi.nlm.nih.gov/31855111/ – This systematic review and meta-analysis on Irvingia gabonensis included multiple RCTs and found significant reductions in body weight, BMI, and waist circumference, along with cardiovascular benefits. The study highlighted the efficacy of Irvingia gabonensis for weight management in overweight and obese adults, despite some heterogeneity in study design.
https://pubmed.ncbi.nlm.nih.gov/34107109/ – This robust meta-analysis on Grape Seed Extract (GSE) included 19 controlled trials and demonstrated significant reductions in oxidative stress markers (malondialdehyde, oxidized LDL) and hs-CRP. It provided clear effect sizes and confidence intervals, supporting GSE's role in mitigating oxidative stress and inflammation, though acknowledging variability in doses and populations.
https://www.archivesofmedicalscience.com/A-systematic-review-and-meta-analysis-of-clinical-trials-investigating-the-effects,74141,0,2.html – This meta-analysis investigated the effects of flaxseed extract on plasma C-reactive protein (CRP) concentrations, including 17 RCTs. It concluded that flaxseed had no significant effect on CRP levels, noting high heterogeneity among studies and suggesting the need for larger, longer trials to clarify its anti-inflammatory potential.
https://nutrition-evidence.com/article/341968/the-effects-of-seed-extract-supplementation-on-anthropometric-and-cardiovascular-outcomes-a-systematic-review-and-meta-analysis – This systematic review and meta-analysis examined the effects of various seed extracts on anthropometric and cardiovascular outcomes. It provided a comprehensive overview of the evidence, highlighting the differential efficacy and mechanisms of action across different seed types, and underscored the importance of high-quality research.
https://onlinelibrary.wiley.com/doi/10.1111/ijcp.14469 – This source likely contributes to the understanding of the clinical pharmacology and efficacy of seed extracts, potentially detailing specific mechanisms or clinical trial outcomes. Its inclusion suggests a focus on the practical application and therapeutic potential of these supplements in a clinical context.
https://www.semanticscholar.org/paper/The-effect-of-grape-seed-extract-supplementation-on-Foshati-Rouhani/df3295cc71b15c3d33470eff59deea545ba7f199 – This paper, likely a meta-analysis or systematic review by Foshati and Rouhani, specifically investigates the effect of grape seed extract supplementation. It contributes to the evidence base regarding GSE's impact on various health markers, reinforcing findings related to its antioxidant and anti-inflammatory properties.