Jarlsberg cheese is a genuinely nutritious option among cheeses, with an unusually high protein and calcium content plus a unique fermentation process that produces meaningful amounts of vitamin K2. At 364 calories and 28 grams of protein per 100 grams, it’s calorie-dense like most cheeses, but it carries some specific health advantages that set it apart from the pack.
Nutritional Profile at a Glance
A 100-gram serving of Jarlsberg Original contains 364 calories, 28 grams of protein, 28 grams of total fat (18 grams saturated), and 780 milligrams of calcium. That calcium number is notable: it covers roughly 60% to 78% of most adults’ daily needs in a single 100-gram portion. For context, a typical slice of Jarlsberg weighs about 20 to 30 grams, so a couple of slices on a sandwich delivers around 150 to 230 milligrams of calcium along with 6 to 8 grams of protein.
The saturated fat content is on par with other semi-hard cheeses like cheddar or Gouda. If you’re watching saturated fat intake, portion size matters more than the type of cheese you pick. The sodium content is relatively low compared to many popular cheeses. Cheddar, for example, averages about 1.7 to 1.8 grams of salt per 100 grams, and Jarlsberg typically falls well below that range.
The Vitamin K2 Advantage
What makes Jarlsberg genuinely different from most cheeses is its fermentation. The bacteria used to make it, called Propionibacterium freudenreichii (the same one responsible for the characteristic holes), produces several forms of vitamin K2 during the aging process. Lab analysis of Jarlsberg shows it contains about 40.5 micrograms of a long-chain form of K2 per 100 grams, plus smaller amounts of other K2 variants totaling around 37 micrograms. That’s a substantial natural source of a vitamin most people don’t get enough of.
Vitamin K2 plays a key role in directing calcium to your bones and teeth rather than letting it accumulate in your arteries. It activates proteins that bind calcium into bone tissue, which is why researchers have been particularly interested in Jarlsberg’s potential for bone health. The bacteria in Jarlsberg also produce a compound called DHNA, which appears to independently stimulate bone-building activity. This combination of K2 and DHNA is relatively unique to cheeses made with this specific bacterial strain.
What the Bone Health Studies Found
A clinical trial published in BMJ Nutrition, Prevention & Health tested daily Jarlsberg consumption against a comparison cheese that lacked the Propionibacterium fermentation. Participants eating Jarlsberg showed increases in osteocalcin, a protein that reflects active bone building. They also showed improved carboxylation of osteocalcin, meaning the vitamin K2 was helping that protein do its job of incorporating calcium into bone.
A separate study in 10 postmenopausal women and 10 men over 55 found that daily cheese intake raised osteocalcin levels significantly in both groups. Perhaps more telling, a marker of bone breakdown (CTX) decreased significantly in both men and women, while the ratio of bone-building to bone-breakdown markers improved. In practical terms, the cheese appeared to shift the balance toward building bone rather than losing it.
These are small studies, and they don’t prove Jarlsberg prevents osteoporosis. But the biological signals are consistent and point in a promising direction, particularly for older adults already at risk of bone loss.
Possible Blood Sugar Benefits
An unexpected finding from the clinical research was that daily Jarlsberg consumption was associated with a decrease in HbA1c, a marker of average blood sugar over the previous two to three months. This effect was specific to the Jarlsberg group and wasn’t seen with the comparison cheese. Researchers attributed it to the DHNA and vitamin K2 produced during fermentation, though the exact mechanism isn’t fully understood. This doesn’t make Jarlsberg a diabetes treatment, but it’s an intriguing signal that the fermentation compounds may have metabolic effects beyond bone health.
Lactose Tolerance
If you’re lactose intolerant, Jarlsberg is one of the safest cheeses you can eat. Its lactose content measures less than 1 milligram per 100 grams, making it essentially lactose-free. Like its Swiss cousin Emmentaler, the combination of bacterial fermentation and aging breaks down virtually all the lactose during production. Most people with lactose intolerance can eat Jarlsberg without any digestive issues.
How Jarlsberg Compares to Other Cheeses
Nutritionally, Jarlsberg sits in a similar range to other semi-hard cheeses for calories, protein, and fat. Where it separates itself is in three areas:
- Vitamin K2 content: Significantly higher than most cheeses due to its unique bacterial fermentation. Soft cheeses and standard cheddars contain little to no K2 from Propionibacterium.
- Sodium: Lower than cheddar and many other popular varieties, making it a better fit for people managing blood pressure.
- Lactose: Essentially zero, putting it among the most tolerable cheeses for sensitive individuals.
The main downside is the same as any full-fat cheese: it’s calorie-dense with a high proportion of saturated fat. A couple of slices a day fits easily into most diets. Eating large amounts daily adds up quickly in both calories and saturated fat, which could offset the bone and metabolic benefits. The clinical studies used modest daily portions, and that’s a reasonable approach for getting the benefits without overdoing it.