Citrus paradisi seed extract
Also known as: Grapefruit seed extract (GSE), Citrus seed extract, Citrus paradisi seed extract
Overview
Citrus paradisi seed extract, commonly known as grapefruit seed extract (GSE), is a botanical extract derived from the seeds of the grapefruit (*Citrus paradisi*). It is marketed as a flavonoid-rich supplement with potential benefits for metabolic health, lipid management, and antioxidant support. The extract is often standardized to its flavonoid content, including compounds like naringin, narirutin, apigenin, and poncirin. While whole citrus fruits have been studied more extensively, direct evidence on the seed extract itself is limited. Research on whole citrus suggests potential benefits, but seed-specific effects require further investigation. The extract is available in various forms, including capsules, tablets, and liquids, and is sourced directly from grapefruit seeds.
Benefits
Limited evidence suggests potential benefits of grapefruit seed extract. A meta-analysis of grapefruit interventions indicates a modest reduction in systolic blood pressure (-2.43 mmHg, 95% CI: -4.77 to -0.09). Preclinical studies suggest that citrus extracts may reduce total cholesterol levels, but these findings are primarily based on animal data. Human studies have not shown a significant effect on body weight (MD: -0.45 kg, 95% CI: -1.06 to 0.16). It's important to note that many studies focus on whole citrus or blends, making it difficult to isolate the specific effects of the seed extract. More research is needed to confirm these benefits and determine the optimal dosage and duration of use.
How it works
The proposed mechanisms of action for Citrus paradisi seed extract involve several biological pathways. Flavonoids in the extract, such as naringin, are metabolized into active forms like naringenin, which may inhibit HMG-CoA reductase, similar to statins, potentially reducing cholesterol synthesis. The extract may also activate PPAR-α, promoting lipid oxidation. Additionally, it may act as an ACE inhibitor, contributing to blood pressure regulation. However, the bioavailability and specific effects of these mechanisms in humans require further study to fully understand how the extract interacts with body systems.
Side effects
Common side effects of Citrus paradisi seed extract include gastrointestinal discomfort, which is often dose-dependent. There is a theoretical risk of drug interactions due to CYP3A4 inhibition, although this is less established than with whole grapefruit. The extract is contraindicated during pregnancy due to insufficient safety data and should be avoided by individuals taking anticoagulants due to potential flavonoid effects. Caution is advised for individuals with hepatic impairment, as limited detoxification studies exist. It is important to consult with a healthcare professional before using this extract, especially if you have any underlying health conditions or are taking medications.
Dosage
The effective dosage range for Citrus paradisi seed extract is approximately 250-300 mg/day of flavanone-glycosides, equivalent to around 500 mg of a standardized extract. It is recommended not to exceed 1,000 mg/day, based on extrapolations from citrus flavonoid trials. The extract should be taken with meals to enhance absorption. When selecting a product, opt for one standardized to contain at least 50% flavonoids. Individual responses may vary, and it is advisable to start with a lower dose to assess tolerance. Consult with a healthcare professional to determine the appropriate dosage for your specific needs.
FAQs
Does it aid weight loss?
Clinical trials have not demonstrated a significant effect on weight loss. While some studies suggest potential metabolic benefits, these have not translated into clinically meaningful weight reduction.
Is it safer than whole grapefruit?
It likely poses fewer drug interaction risks compared to whole grapefruit due to lower concentrations of interacting compounds, but direct comparative studies are lacking to confirm this.
How long until results?
Based on citrus trials, lipid effects may take 8-12 weeks to emerge. However, individual responses can vary, and consistent use is necessary to assess potential benefits.
What are the main active compounds?
The main active compounds are flavonoids such as naringin, narirutin, apigenin, and poncirin. These compounds are believed to contribute to the extract's potential health benefits.
Are there any risks for people with liver problems?
Caution is advised for individuals with hepatic impairment due to limited detoxification studies. Consult with a healthcare professional before using this extract if you have liver problems.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/25880021/ – This systematic review of 3 RCTs (n=250) found no significant weight loss benefit from grapefruit interventions, but did observe a minor improvement in blood pressure. The review notes limitations due to the heterogeneity of interventions, which included whole fruit versus juice.
- https://www.semanticscholar.org/paper/The-effect-of-grapefruits-(Citrus-paradisi)-on-body-Onakpoya-O%E2%80%99Sullivan/6ab39a80ab15a060713562ffc09ebc5518b45761 – This study investigates the effect of grapefruits (Citrus paradisi) on body weight and composition. It provides insights into the potential metabolic effects of grapefruit consumption, although the specific impact of grapefruit seed extract is not directly addressed.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7284884/ – This RCT (n=100, 8 weeks) examined a citrus/olive extract blend (Citroven™) and found improvements in lipid profiles, although the results were not statistically significant compared to placebo. The multi-component formula makes it difficult to isolate the specific effects of grapefruit seed extract.
- https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2022.822678/full – This preclinical meta-analysis indicates that citrus extracts can reduce total cholesterol levels (p<0.01 across models). However, the findings are primarily based on animal data and exhibit high heterogeneity, limiting their direct applicability to human supplementation with grapefruit seed extract.
