What's in Grape Seeds?
While many people discard them, grape seeds are a concentrated source of several beneficial compounds that are often lost when only the fruit's flesh is consumed. These small, bitter seeds are primarily composed of fiber, oil, protein, and a wealth of complex phenols, including tannins and flavonoids.
The power of proanthocyanidins
The key players in grape seed's health-promoting properties are proanthocyanidins, a type of flavonoid. These powerful antioxidants are found in the highest concentrations within the seeds and skins of grapes, particularly those used for winemaking. Their potency lies in their ability to combat oxidative stress, a major contributor to cell damage and chronic disease. Research indicates that grape seed proanthocyanidins have significantly higher antioxidant capacity than well-known antioxidants like vitamins C and E.
Other important components
Beyond proanthocyanidins, grape seeds also contain other valuable nutrients:
- Fatty Acids: Grape seed oil is rich in linoleic acid, an omega-6 fatty acid, which is known for its role in supporting heart health and reducing bad cholesterol levels.
- Vitamins and Minerals: They also provide small but notable amounts of vitamin E, an antioxidant, along with minerals like magnesium, potassium, and calcium.
- Melatonin: This hormone, which regulates sleep-wake cycles, is present in grapes, with the highest concentration found in the seeds as the fruit ripens.
Potential health benefits of eating grape seeds
Incorporating grape seeds, either by chewing whole grapes or consuming them as a processed product, may contribute to several health improvements, though more human research is needed to confirm many of these findings conclusively.
- Cardiovascular Support: The antioxidant and anti-inflammatory properties of proanthocyanidins help protect blood vessels from damage and may contribute to lowering blood pressure. Studies on concentrated grape seed extract (GSE) have shown positive effects on diastolic blood pressure, though results can vary. The compounds may also inhibit the oxidation of LDL ('bad') cholesterol, a key step in the development of atherosclerosis.
- Improved Circulation: Grape seed compounds can have a blood-thinning effect, which improves blood flow and can reduce the risk of blood clots. This effect is particularly noted in studies on leg swelling caused by prolonged sitting.
- Reduced Inflammation: The potent antioxidants in grape seeds have a strong anti-inflammatory effect, which can help manage conditions exacerbated by chronic inflammation, such as arthritis.
- Brain Health: The flavonoids in grape seeds show promise in supporting cognitive function and potentially delaying the onset of neurodegenerative diseases like Alzheimer's by reducing oxidative stress in the brain. One study even suggests memory improvements in older adults taking a daily dose of GSE.
- Wound Healing and Skin Health: Topical application and oral supplementation of grape seed extract have been studied for their ability to enhance skin appearance and speed up wound healing due to high levels of proanthocyanidins. They can also help protect the skin from UV damage.
The difference between eating seeds and taking extract
It's important to understand the different ways to consume grape seeds and how they deliver their benefits. There is a significant distinction between chewing whole seeds and taking a concentrated extract.
Comparison: Whole Seeds vs. Grape Seed Extract
| Aspect | Eating Whole Grape Seeds | Taking Grape Seed Extract (GSE) |
|---|---|---|
| Preparation | Consumed directly with the grape. Must be chewed to release beneficial compounds. | A concentrated supplement made by drying, grinding, and processing seeds. |
| Potency | Offers a less concentrated and more variable dose of beneficial compounds. | Provides a highly concentrated and standardized dose of proanthocyanidins. |
| Absorption | Can be less effective. If swallowed whole, seeds may pass through the digestive system undigested, and the compounds are not absorbed. | More effective and reliable absorption due to concentration and processing. |
| Flavor | Bitter and astringent taste, which some find unpleasant. | Taste is neutralized in capsule or tablet form. |
| Convenience | Integrated into the natural process of eating grapes. | Easy to take as a daily supplement, especially if you prefer seedless grapes. |
| Potential Risks | Lower risk of interaction compared to concentrated forms, but should be considered if on certain medications. Choking hazard for children. | Higher concentration means greater potential for interaction with blood thinners, so medical consultation is important. |
How to safely incorporate grape seeds into your diet
For those interested in exploring the benefits, there are several ways to incorporate grape seeds into your diet. For maximum absorption from whole seeds, it is essential to chew them thoroughly. If you find the taste unappealing or are looking for a more potent dose, concentrated options are available.
- Eat the seeds whole (chewed): Simply chewing and swallowing the seeds along with the fruit is a straightforward approach. While some may dislike the bitter flavor, it is the most natural method.
- Add them to smoothies: For a milder taste, you can blend whole grapes (including the seeds) into a smoothie. This ensures you consume the ground seeds without the bitter taste being overpowering.
- Use grape seed oil: This versatile cooking oil is extracted from the seeds and is known for its high smoke point, making it suitable for frying and roasting.
- Try grape seed flour or meal: Available from health food stores, this powdered form can be added to muesli, yogurts, or baked goods for a nutritional boost.
- Consider supplements: For the highest concentration of beneficial compounds, grape seed extract (GSE) is available in capsule or tablet form. This is ideal for those who want a standardized dosage.
Important precautions
While grape seeds are generally safe for most people, certain individuals should exercise caution or avoid them altogether:
- Blood-thinning medications: The blood-thinning effect of concentrated grape seed compounds may interfere with anticoagulant medications like warfarin or aspirin. Always consult a doctor before starting any grape seed supplements if you are on blood thinners.
- Pregnant and breastfeeding women: Due to a lack of sufficient data on its safety, grape seed extract is not recommended for pregnant or lactating individuals.
- Children: There is a choking risk associated with eating whole grape seeds, so caution should be used when serving them to children.
Conclusion
There is compelling evidence that suggests there is indeed a benefit to eating grape seeds, primarily due to their high concentration of potent antioxidants known as proanthocyanidins. These compounds have been linked to potential improvements in cardiovascular health, circulation, inflammation, and brain function. However, the benefits are most pronounced when the seeds are chewed to release the compounds or consumed in a concentrated extract form. While eating whole grapes with seeds is a simple way to boost your intake of these antioxidants, supplements or processed products like grape seed oil or flour offer a more efficient and potent delivery method. As with any supplement, consulting with a healthcare provider is recommended, especially for individuals with pre-existing health conditions or those on medication.
