ISLAMABAD - Exposing a child to the nuclear radiation from two or three computed tomography (CT) head scans may triple its risk of developing brain cancer later in life. 

The risk of developing cancer comes from the ionizing radiation used in CT scans. The risk is higher in children, who are more radiosensitive than adults. A 20-year study published on Thursday also found that a child exposed to the cumulative radiation of between five and 10 CT scans is three times more likely than an unexposed child to develop leukemia.
While the absolute risk of cancers developing after a CT scan, a diagnostic technique often used on children with possible head injuries, is still small, the researchers advise lowest possible radiation doses with alternatives to ionising radiation.
“This work emphasizes the very great importance of only using this form of imaging when it has a strong medical justification,” says Bruce Armstrong, professor of public health at Sydney University in Australia.
One alternative to a CT scan is ultrasound, which involves no radiation, but is less accurate. A study published last month found that it may also be safe to postpone CT scans in some cases of childhood head injuries.
A total of 74 out of 178,604 patients were diagnosed with leukemia and 135 of 176,587 were diagnosed with brain cancer, and the researchers calculated the relative risk of leukemia increased by 0.036 for every mGy received, while the increased risk of a brain tumor was 0.023.
“Alternative diagnostic procedures that do not involve ionizing radiation exposure, such as ultrasound and MRI (magnetic resonance imaging) might be appropriate in some clinical settings,” he added.
Calcium supplements with vitamin D lengthen seniors’ lives
Seniors who take calcium supplements along with vitamin D may lengthen their lives, a new analysis suggests. However, only the combination of the two appears to be effective, whence mortality was reduced 9 percent, and combination reducing bone fractures, osteoporotic in older people; while vitamin D by itself had no benefit.
Dr Lars Rejnmark, an assistant professor at Aarhus University Hospital in Denmark. Says that “Calcium with vitamin D has now been proven to reduce risk of fractures and death in the elderly.”
Recently there has been data tying calcium supplements to an increased risk of heart attack, as a study in the May edition of Heart found that calcium supplementation increased the risk of heart attack by 86 percent; but not by calcium from foods.
The US Preventive Services Task Force have proposed that postmenopausal women not take low-dose calcium and vitamin D supplements daily to ward off bone fractures, because the effect is negligible. Although the exact mechanism of why these supplements prolong life isn’t known, Holick believes that both improve cell function and cardiovascular health.
Holick recommends adults take 1,500 to 2,000 international units of vitamin D daily with 1,000 to 1,200 milligrams of calcium from both diet and supplements in combination to preserve your bone health, you will improve muscle strength and health benefits including [lowering the] risk of cardiovascular disease, certain cancers, type 2 diabetes and infectious diseases,” Holick said, adding that there was no downside to increasing vitamin D intake.
Decade of dark chocolate possibly reduces heart attacks
A scientific study claims that eating dark chocolate every day for 10 years could reduce the likelihood of heart attacks and strokes in some high-risk patients.
A team of researchers from Australia used a mathematical model to predict the long-term health impact of daily dark chocolate consumption in 2,013 people with a condition known as metabolic syndrome, which puts them at high risk of heart disease.
The team found that in the best case scenario — with no patient missing any daily portions — the treatment could potentially avert 70 non-fatal and 15 fatal heart attacks or strokes per 10,000 people over 10 years. The model also suggested that mounting effective “dark chocolate prevention strategies” might cost an individual just 25 pounds ($40) a year.
The researchers, whose work was published in the British Medical Journal on Friday, stressed the protective effects have only been shown for dark chocolate containing at least 60 to 70 percent cocoa — not for milk or white chocolate. This is probably due to higher levels of flavoniods in dark chocolate.
But experts, also warn that “Recommendations for daily consumption of dark chocolate will certainly get people with metabolic syndrome excited, but at this point these findings are more hypothetical than proven, and the results need real-life data to confirm,” said Kenneth Ong at the Brooklyn Hospital Center in the United States.
“I suspect that consuming dark chocolate every day for 10 years may have unintended adverse consequences,” he added. “The additional sugar and caloric intake may negatively impact patients in this study, who are overweight and glucose intolerant to begin with.”
All participants in the study, led by Christopher Reid at Monash University in Melbourne, had high blood pressure and metabolic syndrome, but had no history of heart disease or diabetes and were not on blood pressure lowering medication.