The Modest Vitamin K Content of Lentils
Lentils are a highly nutritious legume, packed with protein, fiber, and important minerals. However, when it comes to vitamin K, they are not a powerhouse. For perspective, the United States Department of Agriculture (USDA) reports that 1 cup of cooked lentils (198g) provides approximately 3.4 micrograms of phylloquinone, the primary form of vitamin K. An equivalent serving of raw lentils (1 cup, 192g) contains slightly more at 9.6 micrograms. For adults, the Adequate Intake (AI) for vitamin K is 90 micrograms per day for women and 120 micrograms per day for men. Therefore, a serving of lentils contributes only a small fraction of the daily recommended intake.
What does this mean for your diet?
Because of their low vitamin K content, lentils are considered a safe dietary option for individuals who need to monitor their vitamin K intake, particularly those on anticoagulant medications like warfarin. Consistent intake of vitamin K is more important than high intake for these individuals, and the small amount in lentils is unlikely to cause fluctuations in their blood clotting time. This low content is in stark contrast to the high levels found in many green leafy vegetables.
Lentils vs. High-Vitamin K Foods: A Comparison
To better understand how lentils fit into a balanced diet, it is helpful to compare their vitamin K content with other common foods. The following table illustrates the significant difference in vitamin K concentration.
| Food (Portion) | Approx. Vitamin K (µg) | Source | Daily Value Contribution (women/men) |
|---|---|---|---|
| Lentils (1 cup, cooked) | 3.4 | ~3.8% / ~2.8% | |
| Kale (1 cup, cooked) | >800 | >888% / >666% | |
| Spinach (1 cup, cooked) | >800 | >888% / >666% | |
| Broccoli (1 cup, cooked) | ~109 | ~121% / ~91% | |
| Brussels Sprouts (1 cup, cooked) | ~109 | ~121% / ~91% |
Beyond Vitamin K: A Rich Nutrient Profile
Despite not being a significant source of vitamin K, lentils are an undeniable nutritional powerhouse. They are a valuable addition to nearly any diet due to their high content of other vital nutrients.
- Excellent source of folate: Just one cup of cooked lentils provides a very high percentage of the daily recommended intake of folate, a B vitamin crucial for red blood cell production.
- High in protein and fiber: With around 18 grams of protein and 16 grams of fiber per cooked cup, lentils promote satiety and support healthy digestion.
- Rich in minerals: Lentils are an excellent source of iron, potassium, and manganese, and a good source of zinc, magnesium, and phosphorus.
- Abundant in polyphenols: These bioactive plant compounds act as antioxidants, offering anti-inflammatory and cardio-protective effects.
Health Benefits Beyond a Single Vitamin
Regularly incorporating lentils into your meals can offer numerous health benefits beyond their contribution of individual vitamins. Their combination of fiber, folate, and potassium supports a healthy heart by helping to manage blood pressure and cholesterol levels. The high fiber content aids in digestive health by supporting beneficial gut bacteria. For those managing diabetes, the low glycemic index of lentils helps regulate blood sugar levels. Their versatility also makes them a protein-rich meat alternative for vegetarian and vegan diets.
How to boost iron absorption from lentils
Because plant-based iron (non-heme iron) is less readily absorbed by the body than animal-based iron, combining lentils with a source of vitamin C is beneficial. For instance, a lentil soup with added tomatoes or a lentil salad with bell peppers can significantly enhance iron absorption.
Conclusion
In conclusion, while lentils contain a measurable amount of vitamin K, it is minimal, especially when compared to sources like leafy greens. This low concentration makes them a safe and reliable option for those needing to monitor their vitamin K intake, such as patients on blood thinners. The true strength of lentils lies in their other nutritional contributions, including high levels of protein, fiber, and essential minerals like iron and folate. Incorporating lentils into your diet is an excellent way to boost overall nutrient intake, support digestive and heart health, and enjoy a satisfying, low-fat protein source.
For more information on vitamin K and its functions, refer to the resources from the Office of Dietary Supplements at the National Institutes of Health. NIH Office of Dietary Supplements
