Microbes have a bad name. Most people just think of them as carriers of disease. Indeed, bacteria and other microscopic organisms are often pictured in TV adverts as tiny evil humans that every home-loving person should buy powerful antiseptics to eradicate.

Of course, a few microbes are the cause of major diseases, and some others bring less serious upsets. But it’s unfair of us to think of all microbes as harmful. Many of them fulfil useful purposes in the environment, such as breaking down waste to release chemicals for plants and animals to re-use. And some are vital for our health.

Each of us carries around a whole personal environment of different microbes ¬¬ –on our skin and inside our body. Researchers have coined the term ‘Human Microbiome’ for this, and recently they have been showing how individual it can be and exploring how it affects our health.

We acquire our first microbes as we are born, and our exposure to them increases rapidly over the first few years of life and continues into adulthood. As adults we carry around 10 microbial cells for every one of our own cells. That’s about 100 trillion microbe cells! Our gut alone contains about 2 kg of microbes.

These are not causing us any harm, and many are more than just passive passengers, coming along for the ride. We have learned a lot about the gut microbes, for example. They produce anti-inflammatories, pain killers and some vitamins as well as beneficial antioxidants. Recent research* has shown that people with cancer developing in their colons have a different microbial makeup in their colons to healthy people, which suggests some microbes may be protective against this. And fascinating laboratory work in mice** has suggested that some microbes might be implicated in body fatness, with other interesting work*** opening up about their association with metabolic changes related to type 2 diabetes.
With much of this work it’s far too early to suggest that actively changing gut microbes might be beneficial for humans. But these are interesting findings, and they undermine the simplistic view that microbes are there to be eradicated.

*Link to study on the Human Gut Microbiome and Risk of Colorectal Cancer  http://dx.doi:10.1093/jnci/djt300

**Link to study on the gut microbiome and obesity in mice  http://dx.doi.org/10.1126/science.1241214

***Link to study of the human gut microbiome and metabolic markers  http://dx.doi.org/10.1038/nature12506

Link to study on dietary intervention impact on gut microbial gene richness  http://dx.doi.org/10.1038/nature12480

 

So many enjoyable things seem to be bad for us. But here’s some welcome good news – if you like nuts!

Some of the strongest evidence yet of the health benefits of eating nuts has come from two large US research studies*. These followed 76,000 women and 42,000 men over periods of 30 years and 24 years respectively. The participants were all health professionals, and periodically they were asked to fill in questionnaires about their lifestyle and what they were eating. These studies have produced a lot of good evidence about the health risks and benefits of different foods and aspects of lifestyle.

Recently, researchers have focused on what these studies show about eating nuts**. They found that the more times a person ate nuts each week, the less likely he or she was, on average, to have died during the study period or to have suffered cancer, heart disease or lung disease. Those who said they ate nuts every day did best, but even eating nuts once a week seemed to be associated with health benefits.

Unfortunately, the studies did not record what types of nuts people ate, nor how these were prepared – salted, spiced, roasted or whatever. It is likely, though, that most of the participants, as health professionals, would have been aware of the risks of eating too many salted products.

Interestingly, the frequent nut eaters tended not to be overweight. This does not automatically mean that eating nuts helps you keep slim: for example, the people who ate nuts might have led healthier lifestyles. The researchers therefore carefully took into account all the other factors that might have contributed to the health results they found with nuts, using statistical techniques to tease out what was associated with nut eating. It does indeed seem that eating nuts is associated with lower risk of the major diseases.

This is consistent with a range of earlier, smaller-scale studies, and with the widely supported Mediterranean Diet, which encourages eating 30g of nuts a day and has been shown to be effective at reducing the risk of those diseases.
Nuts contain vitamins, minerals and vegetable nutrients, unsaturated fat (oil) and proteins, and they contribute to dietary fibre.

If you are thinking of adding nuts to your diet, try to avoid added salt and be cautious about the calories in nuts. Because of the oil they contain, some types of nuts have quite a lot of calories for their size, and if you start eating nuts daily, you may need to cut back on the other calories you eat.

*The studies are the Nurses Health Study and the Health Professionals Follow Up Study.
** Link to nuts study: http://dx.doi.org/10.1056/NEJMoa1307352

 

The sun is here! For the first time in several years, much of the UK seems set for a proper spell of summer weather.

Sunshine helps us feel good and allows our bodies to make vitamin D that is important for the health of our bones and for helping to prevent heart disease and cancers. But too much exposure to sunlight brings dangers.

A recent publication* from the Office of National Statistics shows an increase in cancers in the UK and draws particular attention to skin cancer. Between 2002 and 2011, malignant skin cancer increased by 56% in males and 38% in females. It is thought this might be due to sunbathing and the use of sunbeds.

The daily use of a good sunscreen helps protect your skin from prolonged exposure to the ultraviolet (UV) light that induces skin cancer. This can literally save your life.

What you might not realise is that daily use of a sunscreen can also protect your skin from ageing processes and keep it looking younger. This has been demonstrated in a recent, timely, study** carried out in Australia.

This study followed 900 middle-aged adults for over 4 years in a controlled trial and compared a group who used sunscreen daily with a group who decided themselves if and when they used sunscreen. Some of the participants also took beta-carotene tablets – an antioxidant that some people take to lessen skin ageing – while others took a placebo for comparison.

The researchers used an established method for assessing skin ageing, and showed that skin ageing was reduced by 24% in the regular users of sunscreen. They found no benefit from taking the antioxidant tablets.

Enormous amounts of money are spent each year by people trying to keep their skin looking young. Some of these commercial products are effective, but many are expensive and can be of dubious merit.

It is good to have evidence that something as simple and easily available as sunscreen used daily can make a significant difference to skin ageing.

And it should reduce your risk of skin cancer too.

 

*Cancer statistics

http://www.ukhealthforum.org.uk/resources/news-and-rss-feeds/?entryid74=28410

 

**Link to the study: Ann Intern Med.

**Link to a summary:

http://www.jwatch.org/na31253/2013/06/07/more-sunscreen-fewer-wrinkles?query=topic_aging

 

“Non-communicable diseases” are those – such as heart disease, diabetes, cancer and lung disease – which arise from lifestyle and environmental factors rather than from germs and infections. Before the 20th Century, most deaths were due to infectious diseases. Now, nearly two-thirds of deaths worldwide are due to non-communicable diseases.

Tackling this presents an enormous challenge globally. A United Nations meeting in New York in 2011 identified the four major factors that we all need to address: poor diet, physical inactivity, tobacco use and alcohol intake.

But persuading adults to change their lifestyle is far from the whole picture. There is growing evidence that we also need to focus attention on children – and even on babies before they are born!

Some of these diseases have their roots in childhood. Coronary artery disease is one that has been extensively investigated. Many of the risk factors can be shown to have their onset in childhood, when dietary and other habits begin to form under the influence of family members and childhood friends. Parents need better information on the importance of encouraging physical activity and a good diet in their children.

A recent article in The Lancet* goes further and suggests that disease in later life can be affected by what happens to us before we are born. For example, if the mother is poorly nourished or has diabetes, this is associated with her unborn child being at greater risk of developing non-communicable diseases when it reaches adulthood.

There is also some evidence that if a pregnant mother or infant is exposed to certain pollutants in the atmosphere or in food, this too may have an impact on the child in the long term, potentially affecting its immune responses and its neurological and reproductive functions when adult. How this happens probably relates to changes in the way the baby’s DNA is processed during its development, when substantial changes can be passed from cell to cell as they divide and grow. These changes can last and have a knock-on effect in adult life.

These findings add to the urgent need for worldwide action to curb environmental pollution from harmful chemicals.

 

 

*Link to article: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)61609-2/fulltext?rss=yes

 

Have you got the guts to give up alcohol for a month? That’s the challenge put down by Cancer Care UK. Why not help yourself feel better after the excesses of the Festive Season and raise some money for important research?

There’s no surprise that alcohol intake tends to increase in the run-up to the Festive Season, what with all the parties, meals out and celebrations. An occasional blow-out shouldn’t cause you any great problem – provided you are not driving – but it’s important to keep an eye on your overall alcohol consumption. Drinking is not as harmless as we once thought it was.

Alcohol contributes about 4% to cancers. Even a low intake brings some risk of cancer, although keeping to the guidelines should minimise this. As intake rises, the risk increases for liver problems as well: long-term ill health from liver damage is an increasing problem in the UK. Drinking brings an increased risk of accidents. And, of course, there’s also the social side. Uninhibited social behaviour can quickly get out of hand.

All round, the personal, social and health costs of drinking are costing us a lot – far more than the money available for research in tackling the problems.

In an effort to raise awareness – and to raise money for research – Cancer Care UK has challenged people to go for an alcohol-free January, a “dryathlon”. Their website www.dryathlon.org.uk can help you calculate how much you are spending on alcohol. If we were all to give them what we save during one month without alcohol, this would be a major boost for important research on preventing and treating alcohol-related and other cancers. Better still, get others to join in or to sponsor you!

Best of luck.

 

We can get the vitamins we need from a healthy diet containing fruit and vegetables, yet an industry has grown up based on the tempting idea that using supplements to boost our intake will make us even healthier. But will it?

In Britain we spend roughly £400 million pounds a year on supplements, most bought by the middle-aged and elderly. We don’t know how many people use them here but it’s likely to be much the same as in the United States, where one in three people regularly take a vitamin supplement.

But does taking supplements bring any benefits? Over the past few decades there has been a lot of research to find out, comparing the health of those taking supplements with those who didn’t. Unfortunately, many of these studies have not been able to provide a clear answer. They had too few participants or did not go on for long enough, or inconsistencies allowed conflicting interpretations.

There have been some large-scale studies, though. For example, the Cancer Prevention Study in the early 1980s recruited 1 million people and the Women’s Health Initiative another 160,000. Neither showed any substantial benefits from supplements in reducing cardiovascular disease such as heart attacks or stroke. Another study – the Nurses Health Study involving 89,000 nurses over 5 years – indicated that supplements gave some protection from colon cancer. But, worryingly, a study in Sweden of 35,000 women found a 19% increase in breast cancer.

When researchers examined 68 studies involving 230,000 subjects together in a meta-analysis, they found no overall benefit from taking supplements, even though some of the individual studies had suggested there might be.

These somewhat mixed findings have made coherent advice difficult. An absolutely rigorous study has been needed, with enough participants unfailingly taking either the supplement under investigation or an inactive placebo for enough years.

Such a study has now been carried out. The Physicians’ Health Study II involved 14,600 male physicians with a mean age of 64 years, 70 per cent of whom continued for more than 10 years in a randomised controlled double blind trial. Two papers have been published so far*. The first showed no reduction in heart attacks or stroke, the other a modest but statistically significant reduction in cancer (from 18 per thousand person-years down to 17). More papers are likely to follow, covering eye disease and cognitive decline.

So at last there is clear evidence from a rigorously controlled trial that taking vitamin supplements can result in a significant (but modest) reduction in cancer in men. There’s no reason to suppose the findings wouldn’t also apply to women. But there’s an equally clear indication of no benefit in heart disease or stroke. So what advice should be given?

Some people may feel that the modest reduction in cancer warrants the trouble and expense of taking a vitamin supplement. On the other hand, it might be better simply to eat the recommended levels of fruit and vegetables – as people have done for millennia.

 

*Links to the papers:

Gaziano JM et al. Multivitamins in the prevention of cancer in men: The Physicians’ Health Study II randomized controlled trial. JAMA 2012 Oct 17; [e-pub ahead of print]. (http://dx.doi.org/10.1001/jama.2012.14641)

Sesso HD et al. Multivitamins in the prevention of cardiovascular disease in men: The Physicians’ Health Study II randomized controlled trial. JAMA 2012 Nov 7; 308:1751. (http://dx.doi.org/10.1001/jama.2012.14805)

© 2012 How to Live to 110 Suffusion theme by Sayontan Sinha