The investigators' long-term goal is to employ novel methods to improve bone formation and bone density in women (and men) with osteopenia or osteoporosis while also decreasing signs and symptoms of degenerative joint and disc disease that commonly accompany bone loss as well as improve quality of life (QOL). These conditions generally begin silently as early as the menopause transition and progress to osteopenia and osteoporosis during the post-menopausal years in aging women. The investigators also envision this will be beneficial in aging andropausal men with these conditions. The investigators postulate that melatonin in novel combination with other natural bone-protective agents may act in a "chronosynergy" manner to prevent and correct these perturbations, reducing the risk of bone fractures, and lessening the stiffness and pain associated with bone, joint and cartilage degeneration and improving quality of life (QOL). The objective here, which is the investigators' next step in pursuit of our goal, is to assess the efficacy of an alternative therapy that uses a novel combination of bone-forming agents, melatonin, strontium (citrate)/ vitamin K2 (MK7), and vitamin D3 on bone health in a postmenopausal population. Melatonin is a novel alternative to current treatment(s) because it has multiple bone-protective and sleep-promoting activities within the body, and it is relatively safe so it can be used in an aging population without untoward side effects; strontium and vitamin D3 are shown to enhance bone mineralization and improve post-menopausal osteoporosis. The project goal is to identify if this combination therapy improves bone health and QOL compared to women taking placebo. The investigators' central hypothesis is that combination therapy using melatonin, strontium, vitamin K2, and vitamin D3 will improve bone health and overall QOL in postmenopausal women not taking this regimen by reducing osteoclast activity and increasing osteoblast activity and by improving subjective measures of stress, anxiety, depression and menopause-related symptoms.