Boron

Boron, the fifth chemical element, is also is a trace nutrient found primarily in fruits and vegetables. Prunes, grapes and raisins, dates, apples, pears, grains and soybeans, almonds and other nuts, and unprocessed honey all contain boron. The presence of large amounts of boron in apples is probably the reason why cider vinegar helps with arthritis, or at least one of the reasons.
Boron, when taken in the recommended dosage of from 3 milligrams to 9 milligrams daily, has a variety of benefits.
Boron, by activating Vitamin D and oestrogen, helps prevent or alleviate the effects of osteoporosis and other menopausal symptoms in post-menopausal women and those in the middle of menopause.
Boron, by improving brain activity, may prevent memory loss and be valuable in the treatment of Alzheimer's disease. It has also been known to relieve the symptoms of arthritis. Boron also reduces the absorption of aluminium - which is also implicated in Alzheimer's.
Boron seems to have the effect of normalising calcium metabolism - which in turn helps reduce abnormal bone growth such as spondylosis and heel spurs. Abnormal bone growth (lumpy instead of smooth at the ends) also contributes to osteoarthritis - hence the usefulness of boron for this problem.
Boron is available in 3 milligram capsules and 3 milligram and 6 milligram tablets, usually in the form of citrate (which is the best absorbed form). Although safe when taken at the recommended doses, boron can, in amounts over 500 mg, cause side effects, including loss of appetite and digestive problems.
Acute boron toxicity produces nausea, diarrhoea, and abdominal cramping. Chronic toxicity also causes nausea, diarrhoea, poor appetite and weight loss.
Boron deficiency contributes to Vitamin D deficiency which can lead to brain wave alteration, arthritis and joint swelling. Like any other supplement, you should consult your doctor before taking boron. And, to prevent negative interactions, let your doctor know of any illnesses you have or have had, and all medications (including over the counter) that you are taking.