Turns out, consuming too much vitamin A may decrease bone thickness, leading to weak and fracture-prone bones.A new study, undertaken in mice, found that sustained intake of vitamin A, at levels equivalent to 4.5-13 times the human recommended daily allowance (RDA), caused significant weakening of the bones, and suggests that people should be cautious of over-supplementing vitamin A in their diets.Vitamin A is an essential vitamin that is important for numerous biological processes including growth, vision, immunity and organ function. Our bodies are unable to make vitamin A but a healthy diet including meat, dairy products and vegetables should be sufficient to maintain the body’s nutritional needs.ome evidence has suggested that people who take vitamin A supplements may be increasing their risk of bone damage.In this study, Dr Ulf Lerner and colleagues from Sahlgrenska Academy at the University of Gothenburg, report that mice given lower doses of vitamin A, equivalent to 4.5-13 times the RDA in humans, over a longer time period, also showed thinning of their bones after just 8 days, which progressed over the ten-week study period.Dr. Ulf Lerner commented, “Previous studies in rodents have shown that vitamin A decreases bone thickness but these studies were performed with very high doses of vitamin A, over a short period of time. In our study, we have shown that much lower concentrations of vitamin A, a range more relevant for humans, still decreases rodent bone thickness and strength.””Overconsumption of vitamin A may be an increasing problem as many more people now take vitamin supplements. An overdose of vitamin A could be increasing the risk of bone weakening disorders in humans but more studies are needed to investigate this. In the majority of cases, a balanced diet is perfectly sufficient to maintain the body’s nutritional needs for vitamin A,” cautioned Lerner.The full findings are present in the Journal of Endocrinology.The authors conclude that there is little justification to use vitamin D supplements to maintain or improve musculoskeletal health, except for the prevention of rare conditions such as rickets and osteomalacia in high-risk groups, which can occur due to vitamin D deficiency after a prolonged lack of exposure to sunshine.Vitamin D supplements have long been recommended for older people to treat or prevent osteoporosis, with some early evidence suggesting benefits for bone health. However, recent large-scale reviews have reported no effect of vitamin D supplementation on bone mineral density, falls or fractures.Vitamin E is a vitamin that dissolves in fat. It is found in many foods including vegetable oils, cereals, meat, poultry, eggs, fruits, vegetables, and wheat germ oil. It is also available as a supplement.Vitamin E is used for treating vitamin E deficiency, which is rare, but can occur in people with certain genetic disorders and in very low-weight premature infants.Some people use vitamin E for treating and preventing diseases of the heart and blood vessels including hardening of the arteries, heart attack, chest pain, leg pain due to blocked arteries, and high blood pressure.Vitamin E is also used for treating diabetes and its complications. It is used for preventing cancer, particularly lung and oral cancer in smokers; colorectal cancer and polyps; and gastric, prostate, and pancreatic cancer.Some people use vitamin E for diseases of the brain and nervous system including Alzheimer’s disease and other dementias, Parkinson’s disease, night cramps, restless leg syndrome, and for epilepsy, along with other medications. Vitamin E is also used for Huntington’s chorea, and other disorders involving nerves and muscles.Women use vitamin E for preventing complications in late pregnancy due to high blood pressure (pre-eclampsia), premenstrual syndrome (PMS), painful periods, menopausal syndrome, hot flashes associated with breast cancer, and breast cysts.Sometimes vitamin E is used to lessen the harmful effects of medical treatments such as dialysis and radiation. It is also used to reduce unwanted side effects of drugs such as hair loss in people taking doxorubicin and lung damage in people taking amiodarone.Vitamin E is sometimes used for improving physical endurance, increasing energy, reducing muscle damage after exercise, and improving muscle strength. for certain inherited diseases and to prevent allergies.
