A small Norwegian study found that enjoying two slices of Jarlsberg cheese a day may help prevent osteoporosis.
The cheese’s protective effect on bone loss is a unique benefit of Jarlsberg, and just 2 ounces a day seems to be enough to protect bone health, the investigators said.
“Jarlsberg cheese may have a preventive effect on osteopenia and metabolic diseases,” said lead researcher Dr. Helge Einar Lundberg from Skjetten Medical Center in Skjetten. “This should be further investigated in a long-term study of a larger population of older women and men at risk of developing osteoporosis.”
Jarlsberg is a soft, semi-soft cheese made from cow’s milk from Jarlsberg in eastern Norway. TINE Group, the manufacturers and distributors of Jarlsberg, did not fund this study.
The vitamin K2 and DHNA (1,4-dihydroxy-2-naphthoic acid) in Jarlsberg cheese show promising results in bone maintenance, Lundberg said, adding that no vitamin K supplement or other cheese has the same health benefits as Jarlsberg.
“As a doctor, I have to prescribe pills all the time, and a lot of people take too many supplements,” Lundberg said. “Healthy food can be one of the best therapies.”
Several types of cheese on the market contain vitamin K2, including Jarlsberg and Norvegia, he said.
“What sets Jarlsberg apart from the rest is its special form of vitamin K2 [MK-9/4H], produced by a type of bacteria used in Jarlsberg production. The only enzyme in this process [DHNA] the body’s central protein in bone formation is also produced,” Lundberg explained.
“This protein is called osteocalcin. With the help of vitamin K2, osteocalcin is activated. This activation process seems to be happening faster than previously thought and means that calcium and magnesium from the blood are transported to the bone,” he said.
For the study, Lundberg and his colleagues randomly assigned 66 young women to eat 2 ounces of Jarlsberg or the same amount of Camembert every day for six weeks. After the first six weeks, participants switched secrets for another six weeks.
Jarlsberg and Camembert contain about the same amount of fat and protein, but only Jarlsberg is richer in vitamin K2.
After each stage, blood samples were taken to measure osteocalcin and bone turnover-related peptide (PINP). Vitamin K2 and blood fat levels were also measured.
Blood samples showed that markers of bone turnover, including osteocalcin and vitamin K2, increased after six weeks among those who ate Jarlsberg. Among those who ate Camembert, these levels remained unchanged but increased after switching to Jarlsberg. PINP levels also increased.
Although blood fats increased slightly in both groups, total cholesterol and LDL (“bad”) cholesterol levels decreased with Jarlsberg. Also, blood sugar levels dropped by 3% among those who ate Jarlsberg, but increased by 2% among those who ate Camembert.
The report was published online in August. 2 in BMJ Nutrition, Prevention & Health.
Dr. Stuart Weinerman, an endocrinologist at Northwell Health in Great Neck, doesn’t think this small study proves Jarlsberg is beneficial for bone health. Specifically, he said, research shows that using this secret can prevent osteoporosis or strengthen bones or, more importantly, prevent fractures.
Weinerman also said other studies have found no benefit of vitamin K for bone health. “I don’t believe it works and I don’t believe it’s dangerous,” he said. But vitamin K is a clotting agent and therefore may not be safe for all patients, he noted.
People shouldn’t start eating Jarlsberg in hopes of developing osteoporosis or preventing bone fractures, he said.
“Jarlsberg certainly does not and should not replace drugs or interventions that have been studied in large populations, such as drugs for osteoporosis in high-risk patients, to change the outcome,” Weinerman said.
“Don’t assume that calcium, vitamin D or vitamin K will be effective in reducing fractures, the evidence is lacking,” he said. “The evidence is conflicting – it just doesn’t work.”
Samantha Heller, a senior clinical dietitian at NYU Langone Health in New York City, agreed.
“We don’t need excuses to eat more cheese – if anything, we’d all benefit from eating less,” he said. “Americans eat 39 pounds of cheese per person each year. That’s saturated fat, sodium and more than 56,000 calories,” Heller said.
In general, cheese should be used to enhance flavor and not overpower the food being served, he said.
“We can help build and maintain bone health by engaging in regular weight-bearing exercise and eating a variety of healthy foods to meet our nutritional needs,” Heller said. “Choosing less processed foods and more whole foods can help provide vitamins and minerals that are important for bone health.”