The purpose of this study is to evaluate the efficacy of salmon bone meal in preventing bone loss among perimenopausal women with reduced bone mass density.

The current study is part of a larger project called the CalGo-project. The overall purpose of the study is to use bone meal from salmon to promote skeletal health. Specifically, the effect of salmon bone meal on bone mass density among perimenopausal women (age ≥ 50 years) with osteopenia is investigated over a time period of 2 years. Salmon bone meal is composed of a natural microcrystalline hydroxyapatite form of calcium and phosphorus, collagen type 2. Past literature on mammalian sources of bone meal has indicated that this form of calcium is superior in terms of preserving bone mass density compared to traditional calcium supplements. Preserving bone mass is essential to reduce the risk of future fragility fractures. Osteopenia is a condition of reduced bone mass density and bone quality which can indicate the later onset of clinical osteoporosis. Both are conditions associated with a significant risk of fragility fractures, which are a major global health burden.

Bone mass density is measured using dual-energy X-ray absorptiometry. Markers of bone formation P1NP and CTX-1 will be measured in serum samples of participants. 100 potential participants will be screened for eligibility. Participants who meet the eligibility criteria will be randomized in a double-blind manner to receive 4 capsules daily of salmon bone meal enriched with Vitamin D3 per capsule.

Inclusion Criteria:

• Female gender
• ≥ 50 years of age
• DXA T-score of > -2.5 standard deviations, but ≤ -1 (osteopenic range)
• Steady state body weight 1 month before study commencement date
• No contraindications for intake of the interventional product, including a prior diagnosis of fish allergy.
• Familiar with the Norwegian language, both in writing and orally

Exclusion Criteria:

• A diagnosis of osteoporosis (BMD T-score ≤ -2.5 SD as diagnosed by DXA), or any previously diagnosed fragility fractures on a background of osteoporosis.

• Use of drugs known to affect bone metabolism, including:

  • Glucocorticoids
  • Thyroid hormones
  • Hormone replacement therapy taken continuously for a duration of less than 6 months.
  • Long-term heparin therapy
  • Anti-convulsive drugs
  • Long-term proton pump inhibitor treatment
  • Lithium
  • Anti-osteoporotic drugs
  • Cancer therapy
  • Selective estrogen receptor modulators.

• Any disease or medical condition known to affect bone tissue, including neoplasia with or without metastasis, Paget's disease of bone, Osteomalacia, or any other disease deemed relevant by the PI.

• Gastrointestinal diseases or disturbances potentially affecting absorption of nutrients, including Crohn's disease and Celiac disease.

• Hypersensitivity to ingredients in the interventional product, including fish allergy.

• Not willing to participate in the study.

• Other reasons that the PI deems it necessary to exclude the subject.