Writing in the journal Frontiers in Nutrition in a two-part publication, researchers from the University of Würzburg conducted a randomized, double-blind, placebo-controlled study which found improvements in bodily pain and vitality scores compared with placebo, as well as changes in bone-resorption markers among participants taking Pycnogenol. The supplement is a polyphenolic extract containing 65–75% oligomeric procyanidins, or plant-derived flavonoid polymers.
“Pain can be highly disruptive to the quality of life in patients with osteoporosis, and participants receiving Pycnogenol reported improvements in the bodily pain domain,” the researchers wrote. “Vitality scores were also significantly higher in the Pycnogenol group than in placebo... Future research should examine if the observed benefits persist with prolonged use and confirm that Pycnogenol facilitates maintaining bone health.”
Besides quality of life, the study evaluated safety indicators and markers related to mineral metabolism and bone resorption. This research was supported by an educational grant from Horphag Research.
Sébastien Bornet, vice president of global sales and marketing at Horphag Research, said the findings build on the company’s research into Pycnogenol and women’s health. He highlighted the extract’s polyphenol profile and its potential antioxidant and anti-inflammatory properties, which he said may be relevant to the oxidative stress and inflammation involved in bone remodeling.
“This latest study builds on our commitment to women’s health,” Bornet told NutraIngredients, adding that the ingredient is backed by four decades of research and more than 30 clinical studies involving 2,400 women.
Aging and inflammation
Often called a “silent” disease, osteoporosis reduces bone mineral density and weakens bone structure, making fractures more likely. Fractures can cause pain, limited movement, disability or early death in older adults, especially women after menopause, who are most impacted.
Additionally, bone marrow stem cells can become fat cells. Producing less bone and more fat contributes to osteoporosis, as increased marrow fat predicts bone loss in older women, and saturated marrow fats are linked to fracture risk.
Aging and inflammation can also push these cells toward making fat rather than bone. Researchers are studying compounds that influence this balance, and some plant polyphenols promote bone formation.
Although medicines can reduce fracture risk, people with osteopenia or stable osteoporosis who do not meet drug-treatment guidelines usually rely on diet, exercise, vitamin D and calcium. Researchers are studying whether polyphenols, plant compounds found in the supplement, can influence bone turnover.
As for Pycnogenol, its effects on bone loss in people with osteopenia or stable osteoporosis had previously been untested in humans, although rodent studies suggest it may reduce bone loss and the formation and activity of bone-breaking cells.
The study tested Pycnogenol in people with osteopenia or stable osteoporosis who were not scheduled for bone-specific medicines. It mainly measured CTX-1, a marker of bone breakdown, and P1NP, a marker of bone formation. These internationally recommended markers show short-term changes and can be measured in blood, urine or saliva. The researchers also measured M1, a metabolite of Pycnogenol, in saliva to assess supplement intake and explore possible associations with the effects. They tested whether selected extract compounds or their breakdown products helped human marrow stem cells become bone-forming cells.
Study details
The study randomly assigned 67 women with bone conditions to take either 200 mg of Pycnogenol a day (33 women) or placebo capsules (34 women) for three months. Participants were then followed for a further three months, during which all women received Pycnogenol.
After three months, participants taking Pycnogenol showed improvements in bodily pain and vitality scores compared with placebo. The researchers reported a 14% improvement in vitality and a 25% improvement in physical comfort scores relative to placebo.
Pycnogenol was also associated with a reduction in CTX-1, a marker of bone resorption, of approximately 11% from baseline after three months. However, this reduction was not significantly different from the change observed in the placebo group. Serum phosphate levels also decreased during supplementation, remaining within the reference range.
One limitation of the study was that CTX-1 levels can be affected by the time of day and whether a person has eaten. Although the researchers tried to collect samples under similar conditions, some differences may still occur. The study included a six-month follow-up, but only the first three months were placebo-controlled. It therefore could not establish whether the observed changes persisted relative to placebo or whether Pycnogenol helps prevent fractures. Larger, longer controlled studies are needed to answer these questions.
Despite these limitations, the study had an important strength: It was the first human clinical trial to examine the effects of Pycnogenol on bone turnover markers in people with low bone mineral density, according to the researchers. The findings suggest that Pycnogenol may influence bone breakdown, but the lack of significant differences between groups means more research is needed to confirm whether it affects bone health or reduces fracture risk.
“We’re at a moment when women are thinking about their health very differently. Menopause is finally getting the attention it deserves, millions of people are experiencing significant weight loss with GLP-1 medications, and both conversations raise important questions about protecting bone health as we age,” said Dr. Fred Pescatore, MD, who was not affiliated with the studies. “Bone health isn’t just about a number on a scan; it can affect how you feel and function every day. That’s why these findings are so interesting.”
Frontiers in Nutrition. doi.org/10.3389/fnut.2026.1923949. Impact of a dietary intervention with French maritime pine bark extract (Pycnogenol) on bone turnover markers in women with osteoporotic bone loss: a randomized, placebo-controlled double-blind study—Part I. Authors: Christian Scherg et al.
Frontiers in Nutrition. doi.org/10.3389/fnut.2026.1924081. Quality of life and safety of a dietary intervention with French maritime pine bark extract (Pycnogenol®) in women with osteoporotic bone loss: a randomized, placebo-controlled double-blind study—Part II. Authors: Christian Scherg et al.
