Free radicals are essential for our health. They are used as molecular messengers that send signals from one region of the cell to another. Without free radicals, cells would continue to grow and divide uncontrollably, also known as cancer.
Free radicals also increase when our bodies are infected with an unwanted bacterium or virus. Free radicals act as a warning method to our immune system.
Millions of people swear by vitamin supplements. But many are wasting their time and some could even be harming themselves, argues Dr Chris van Tulleken. In November 1912 a party of three men and 16 dogs set out from a remote base in eastern Antarctica to explore a series of crevasses many hundreds of miles away.
In Australia's most recent nutrition survey, 29% of people reported having taken at least one dietary supplement. This proportion was even higher in the United States at 52%. A new study out today aimed to examine the benefits of vitamin and mineral supplements for prevention of heart disease, stroke and premature death (termed " all-cause mortality ").
These are dark days for supplements. Although they are a $30-plus billion market in the United States alone, vitamin A, vitamin C, vitamin E, selenium, beta-carotene, glucosamine, chondroitin, and fish oil have now flopped in study after study. If there was one supplement that seemed sure to survive the rigorous tests, it was vitamin D.
Getting vitamin D through supplementation shows zero benefits. A study over a period of 5 years found supplementing with Vitamin D had no impact on cancer, heart disease, or stroke.
A number of researchers now argue that people with high vitamin D levels are healthy not because of the vitamin, but because they get plenty of exposure to the sun. Vitamin D is just a marker of that fact.
A dermatologist discovered our skin uses sunlight to make nitric oxide, a molecule in the body that dilates blood vessels and lowers blood pressure.
He exposed volunteers to the equivalent of 30 minutes of summer sunlight without sunscreen. The result? The nitric oxide levels in the volunteers went up, and their blood pressure lowered. Because of the connection of high blood pressure to heart disease and strokes, this discovery can prevent millions of deaths globally.