Vitamin E "ups prostate cancer risk

US researchers warned Tuesday of an alarming link between vitamin E supplements and a 17 per cent increased risk of prostate cancer, describing the findings as an "important public health concern".

Ten years after the start of a randomised trial of more than 35,000 men, researchers discovered the spike in prostate cancer among those assigned to take vitamin E rather than selenium or a placebo.

"Dietary supplementation with vitamin E significantly increased the risk of prostate cancer among healthy men," said the study in the Journal of the American Medical Association.

Selenium, a trace mineral found in foods like Brazil nuts, tuna and beef, is often deficient in areas such as China and Russia where it is lacking in the soil.

The study was launched based on previous research that had suggested that selenium or vitamin E might reduce the risk of developing prostate cancer.

The latest data emerged three years after a preliminary study of the findings, published in 2008, showed a slightly higher but statistically insignificant risk of prostate cancer among those taking vitamin E.

However, since the risk was approaching statistical significance, a safety committee called for a halt to the randomised Selenium and Vitamin E Cancer Prevention Trial (SELECT) in the United States, Canada and Puerto Rico in 2008.

A longer-term follow up, concluded in July of this year, has revealed the higher cancer incidence in men assigned to the vitamin E portion of the trial.

"Based on these results and the results of large cardiovascular studies using vitamin E, there is no reason for men in the general population to take the dose of vitamin E used in SELECT as the supplements have shown no benefit and some very real risks," said Eric Klein, a study co-chair for SELECT, and a physician at the Cleveland Clinic.

"For now, men who were part of SELECT should continue to see their primary care physician or urologist and bring these results to their attention for further consideration."

The study began in 2001 and broke participants into four groups: one would receive selenium, another would get 400 international units of daily vitamin E, another group would take both, and the fourth was prescribed a placebo.

A total of 620 men in the vitamin E group developed prostate cancer, as did 555 in the combined selenium and vitamin E group.

Those taking selenium only saw 575 develop prostate cancer, compared to 529 on the sugar pill.

"The observed 17 per cent increase in prostate cancer incidence demonstrates the potential for seemingly innocuous yet biologically active substances such as vitamins to cause harm," said the study.

Men entering the trial had no signs of prostate cancer and were considered to exhibit average risk of developing the disease, which is the second most common cancer among US men, after skin cancer.

According to the American Cancer Society, 240,890 new cases of prostate cancer will be diagnosed in 2011 and 33,720 men will die of prostate cancer in the United States.

The study found no biological explanation for why vitamin E was driving the risk higher, but warned that the effects of the pills may continue even after the patient stops taking them.

"The fact that the increased risk of prostate cancer in the vitamin E group of participants in SELECT was only apparent after extended follow-up... suggests that health effects from these agents may continue even after the intervention is stopped," it said.

The findings also "underscore the need for consumers to be sceptical of health claims for unregulated over-the-counter products in the absence of strong evidence of benefit demonstrated in clinical trials," it said.

The trial was funded by the National Cancer Institute, the National Centre for Complementary and Alternative Medicine, the National Heart, Lung, and Blood Institute, the National Institute of Aging and the National Eye Institute.

World population expected to reach 10.1 billion in 2100

World population levels are projected to reach 10.1 billion at the end of the century, according to a new UN report released on Tuesday.

According to the report, titled "2010 Revision of World Population Prospects," the bulk of the expected increase in global population is projected to come from 58 "high-fertility countries" in Africa, Asia, Oceania, and Latin America. The report was prepared by the UN Department of Economic and Social Affairs (DESA) .

Fertility is "the main driver of population rates in the world, " Hania Zlotnik, director of the DESA's Population Division, told reporters here.

"The world hasn't collapsed by adding so many people, but what is important is that most of these people are being added in the poorest countries of the world," said Zlotnik.

Based on the medium projection, the number of people in the world -- currently close to 7 billion -- should pass 8 billion in 2023, 9 billion by 2041 and then 10 billion at some point after 2081, the report said.

Between 2011 and 2100, the population of high-fertility countries is expected to more than triple in size, going from 1.2 billion to 4.2 billion, the report noted. During the same period, the report projected, the population of low-fertility countries will decline by around 20 percent -- from 2.9 billion to 2.4 billion.

Early risers get ahead of the game

Those who fight the urge to ignore the alarm clock complete morning chores faster, pack their children off to school earlier and thrive in the workplace, researchers concluded.

But people who can't resist a lie in have a higher chance of feeling depressed or stressed and becoming overweight.

Researchers questioned 1,068 adults about their levels of happiness and anxiety, their physical health and their eating and sleeping habits in an online survey.

They found that "morning people" were out of bed by 6.58am on average, while "evening people" waited until 8.54am to start their day.

During weekends, both groups enjoyed about an extra hour under the covers, with early risers waiting until 7.47am to get up and night owls lying in until 10.09am.

Dr Joerg Huber of Roehampton University said: "There are morning people and evening people, and morning people tend to be healthier and happier as well as having lower body mass indices."

The reason early risers do better in life could be down to the fact that getting the chores out of the way and the children out of bed in good time helps people fit in better with hectic modern life, he told a British Psychological Society conference.

"Maybe morning types are just better suited to this industrial world we are in than late risers", he said.

The differences between the two groups are small and there can be certain advantages to being an evening person, for example in jobs that require you to work late, he added.

The survey also found that people who watch a lot of television are more likely to skip breakfast.

This could be because they snack more while spending their evening on the sofa and are less hungry in the morning as a result, Dr Huber said.

Colon cancer advances faster in men

Men with colon cancer tend to have more advanced tumors than women of the same age, said a study out Tuesday that suggested screening guidelines may need to be adjusted for sex and age.

Currently, men and women age 50 and older are urged to get a colonoscopy to screen for growths or polyps that could form into tumors. Colorectal cancer is the fourth leading cancer killer worldwide, taking 610,000 lives per year.

The study in the Journal of the American Medical Association examined 44,350 participants in a national screening colonoscopy program from 2007 to 2010 in Austria.

The screenings look for adenomas, which are polyps or benign tumors as well as for particularly advanced adenomas and colorectal cancer.

The analysis found "a significantly higher rate of these lesions among men compared with women in all age groups, suggesting that male sex constitutes an independent risk factor for colorectal carcinoma," according to the study.

For instance, five percent of men age 50-54 had advanced adenomas compared to just 2.9 percent of women.

The rate of colorectal cancer in 55-59-year-old men (1.3 percent) was about the same as in women a decade older (65-69-year-old women were diagnosed at a rate of 1.2 percent).

The prevalence of colorectal cancer overall was twice as high among men, at 1.5 percent, compared to 0.7 percent in women.

The researchers noted that "deciding whether to adjust the age at which screening begins also requires considering whether the recommended age for women should be older or the recommended age for men younger."

However, the study stopped short of saying what that new age should be, saying further studies "are needed to demonstrate the relative clinical effectiveness of screening at different ages."

Eyelid marks warn of heart attack

Yellow markings on the eyelids are a sign of increased risk of heart attack and other illnesses, say researchers in Denmark.

A study published on the BMJ website showed patients with xanthelasmata were 48% more likely to have a heart attack.

Xanthelasmata, which are mostly made up of cholesterol, could be a sign of other fatty build-ups in the body.

Cardiologists said the findings could be used by doctors to help diagnose at-risk patients.

The research team at the Herlev Hospital in Denmark started following 12,745 people in the 1970s.

At the start of the study, 4.4% of patients had xanthelasmata.

Yellow alert

Thirty three years later, 1,872 had had a heart attack, 3,699 had developed heart disease and 8,507 had died - and the data showed that those with the yellow markings around the eyes were at greatest risk.

Those with the markings were 48% more likely to have a heart attack, 39% more likely to have developed heart disease and 14% more likely to have died during the study.

The authors believe patients with xanthelasmata may be more likely to deposit cholesterol around the body.

A build up of fatty material in the walls of arteries - known as atherosclerosis - leads to stroke and heart attack.

For both men and women in several age groups, the data said there was a one in five chance of developing heart disease in the next decade if the patient had xanthelasmata.

The authors said such patients were "generally considered to be at high risk" and should have "lifestyle changes and treatment to reduce [bad] cholesterol."

However they warned that: "Today, most people with xanthelasmata are seen by dermatologists, when they want their xanthelasmata removed for cosmetic reasons.

"Some of these people may not have been managed according to their increased risk of cardiovascular disease."

A review of the study, by US cardiologists Antonio Fernandez and Paul Thompson, concluded that: "Xanthelasmata could be used by general clinicians to help identify people at higher risk of cardiovascular disease."

Judy O'Sullivan, senior cardiac nurse at the British Heart Foundation, said: "There are many different techniques to predict someone's risk of developing heart disease in the future, none of which are perfect. The most important thing is that any one of these techniques is used in the first place."

Coffee shown to reduce risk of skin cancer

Coffee has been shown to reduce the risk of skin cancer by helping kill off damaged cells that could otherwise turn into tumours, according to a US study published on Monday.

The findings indicate that moderate caffeine drinking, or perhaps even applying coffee to the skin, could be useful in warding off non-melanoma cancer, the most commonly diagnosed of all skin cancers.

Using mice that had been genetically altered to suppress a protein enzyme called ATR, researchers showed that the mice were able to fend off cancer even when exposed to ultraviolet light.

Previous studies have suggested that drinking about a cup of caffeinated coffee per day has the effect of suppressing ATR and triggering the die-off of cells harmed by UV rays.

The altered mice eventually did develop cancer, but three weeks later than normal mice, according to the study published in the Proceedings of the National Academy of Sciences.

After 19 weeks of ultraviolet light exposure, the engineered mice showed 69 percent fewer tumours and four times fewer invasive tumours than the control group.

However, the protective effects only went so far. After 34 weeks of UV exposure, all the mice developed tumours.

"Eventually, if you treat them long enough, the mice will develop cancer so it is not 100 percent protection forever," Allan Conney, one of the study's authors, told AFP.

"Really, with almost any carcinogen, eventually all the animals will develop tumours," added Conney, who is director of the Susan Lehman Cullman Laboratory for Cancer Research at Rutgers University in New Jersey.

Conney and his team were able to confirm their hypothesis that caffeine - when consumed or applied to the skin - works by inhibiting ATR. Now they say more studies are needed to see how it may work on humans.

"We want to see whether caffeine has an effect in people when you give it topically," he said.

"Caffeine might become a weapon in prevention because it inhibits ATR and also acts as a sunscreen and directly absorbs damaging UV light."

Skin cancer is the most prevalent cancer in the United States, with more than one million new cases each year, according to the National Cancer Institute.

Non-melanoma types of skin cancer, including basal cell and squamous cell types, are the most commonly diagnosed and are often treatable if detected early.

Previous studies have shown coffee drinkers tend to have fewer incidences of breast, uterine, prostate and colon cancers, but the beneficial effects are not seen in people who drink decaffeinated coffee.

What is tuberculosis?

TB most commonly affects the lungs, but can affect almost any part of the body. It can be spread when someone with the infection coughs, sneezes or talks and another person breathes in the bacteria. However, prolonged contact is usually needed for infection to occur.

Some people develop a minor infection, which then settles as their immune system fights it and evidence is only found later incidentally as a scar on a chest x-ray. For others, active TB flares up many years after the initial infection. If the initial infection isn't fought off, it can progress to serious ongoing infection a few weeks after the first contact.

Tuberculosis symptoms

Initially, there may be no symptoms. When symptoms develop, they will vary depending on which part of the body is affected. However, they commonly include:

• A persistent cough, usually for more than three weeks - it may be dry to start with and progress to blood-streaked sputum
• Night sweats for weeks or months
• Weight loss
• Fatigue
• High temperature
• Shortness of breath.
  

  Tuberculosis causes

  It's estimated that one-third of the world's population is infected with the bacteria that causes TB. Each year about nine million people develop the disease and up to nearly two million people worldwide are killed by it. Figures from the Health Protection Agency show there were 8,417 cases in the UK in 2007.

  Anyone can get TB. People at greater risk of developing it include:

• Children and older people
• Smokers
• Those living in overcrowded conditions
• Those who have a poor diet
• People with HIV
• The homeless
• Those who have a weakened immune system because of other medical conditions, such as diabetes, or because of other medical therapy, such as immuno-suppressant medication

Tuberculosis treatments

TB is difficult to treat - normal antibiotics don't kill TB bacteria. Combinations of several special antibiotics treat the infection in the majority of cases. These must be taken for long periods, usually at least six months, to avoid becoming ill with TB again and developing a drug-resistant form of the disease.

Even with treatment, some people develop long-term complications from infection.

Travellers to countries where TB is prevalent are at greater risk. A vaccine is available, which is offered to those at high risk of contracting the disease. Check with your doctor whether your travel plans put you at risk of TB and discuss possible vaccination.