Understanding Vitamin K2 in Cheese
Vitamin K is a fat-soluble vitamin crucial for several bodily functions, including blood clotting, bone metabolism, and cardiovascular health. While leafy greens provide vitamin K1 (phylloquinone), animal products and fermented foods contain vitamin K2 (menaquinones, or MK-n). Swiss cheese and other fermented dairy products are known to contain vitamin K2, but the concentration can vary substantially depending on the type of cheese.
The Role of Bacteria in Producing K2
The presence of vitamin K2 in Swiss cheese is not inherent to the milk itself but is a byproduct of the bacterial fermentation process during cheesemaking. Different bacterial strains produce different forms of menaquinones, which are designated with an MK-n number. For instance, the 'eyes' or holes characteristic of Emmentaler are formed by propionic acid bacteria, which are responsible for producing MK-9(H4). Mesophilic lactic acid bacteria also contribute to menaquinone formation. The specific combination of bacteria, along with environmental factors during production, determines the final vitamin K2 profile of the cheese.
How K2 Content Differs Among Swiss Varieties
Not all Swiss cheeses contain the same amount of vitamin K2. A study of 121 Swiss cheese samples found significant variations in menaquinone content.
- High Content: Researchers found the highest average levels of vitamin K2 in varieties like Raclette (465 µg/kg), Vacherin Fribourgeois (456 µg/kg), and Emmentaler (280 µg/kg). This is likely due to the specific bacterial cultures and conditions used in their production.
- Lower Content: Alpine and Mountain cheeses, including some varieties of Gruyère, generally contained lower levels of menaquinones. This can be attributed to the use of thermophilic bacterial strains or higher heating temperatures during their production, which can reduce menaquinone synthesis.
- Ripening and Fat Content: Older, more ripened cheeses tend to have higher levels of long-chain menaquinones compared to younger ones. Additionally, because vitamin K2 is fat-soluble, higher fat content is often associated with higher K2 concentrations.
Comparing Vitamin K2 Sources
While Swiss cheese is a notable source of vitamin K2 in Western diets, it is important to understand how it stacks up against other dietary sources. The following comparison table helps illustrate the relative concentration of K2 in Swiss cheese compared to other foods. Note that values can vary depending on brand, production methods, and ripeness.
| Food Source | Primary K2 Form | Approximate K2 Content (per 100g) | Notes |
|---|---|---|---|
| Natto (fermented soybeans) | MK-7 | 800–1,100 μg | Exceptionally high concentration. |
| Gouda Cheese (Dutch) | MK-8, MK-9 | ~65 μg | Considered a strong source. |
| Emmental Cheese (Swiss) | MK-9(H4) | ~28–43 μg | Varies significantly,. |
| Blue Cheese | MK-8, MK-9 | ~36–49 μg | High variability,. |
| Raclette Cheese (Swiss) | Various MK-n | ~46–47 μg | High among Swiss varieties,. |
| Chicken Thigh (with skin) | MK-4 | ~53 μg | Concentrated MK-4 source. |
| Egg Yolk (pastured) | MK-4 | ~37 μg | Moderate MK-4 source. |
| Swiss Cheese (average) | Various MK-n | ~8–10 μg | Lower end of the spectrum for a general Swiss. |
Health Benefits of Vitamin K2
Getting an adequate amount of vitamin K2 is important for health. The specific forms of menaquinones (MK-n) found in aged, fermented cheeses like Swiss are often long-chain types (e.g., MK-9). These long-chain menaquinones are particularly effective at reaching extra-hepatic tissues like the arterial vessel wall and bone, potentially offering better protection against cardiovascular disease and aiding bone health compared to K1.
Key Health Benefits include:
- Bone Health: Vitamin K2 activates proteins like osteocalcin, which helps shuttle calcium into bone tissue. This is a critical process for maintaining bone mineral density and reducing fracture risk, especially as we age.
- Cardiovascular Health: K2 also helps prevent arterial calcification by activating matrix Gla protein, which inhibits calcium from depositing in soft tissues like arteries. This may significantly reduce the risk of cardiovascular disease,.
- Blood Clotting: While K1 is more directly involved, K2 also plays a role in blood coagulation.
Maximizing K2 Intake from Swiss Cheese
To maximize your intake of vitamin K2 from Swiss cheese, consider the following:
- Choose the Right Type: Opt for Emmentaler, Raclette, or Vacherin Fribourgeois, as these have been shown to have higher average menaquinone levels.
- Check Ripeness and Fat: Since K2 levels increase with age and are fat-soluble, opt for more mature, full-fat Swiss cheese varieties,.
- Pair Strategically: Combine Swiss cheese with other K2-rich foods to boost your intake. For example, add it to omelets with pastured egg yolks or pair it with other aged cheeses.
Conclusion
Ultimately, the question of "Does Swiss cheese have vitamin K2?" is a resounding yes, but the concentration is not uniform across all varieties. Aged, higher-fat Swiss cheeses, particularly those fermented with specific bacterial cultures like Emmentaler, contain notable amounts of menaquinones, predominantly MK-9(H4). While not the most concentrated source of K2 available, consuming Swiss cheese can still contribute to your daily vitamin K2 intake, supporting essential functions like bone and cardiovascular health. By understanding the factors influencing K2 content, consumers can make informed choices to enhance their nutritional benefits.
For additional research and information on menaquinone content in various cheeses, the following link provides a comprehensive resource: NIH-PMC page on Menaquinone Content.
