Life Science

lifescience

Viva! Health dissects the latest scientific research and makes it easy to understand. Here we update you on recent findings…

BY DR JUSTINE BUTLER, HEAD OF RESEARCH, VIVA!

Chicken dinner –the consequences

It’s a major driver of wild bird losses

Catastrophic declines in wild birds are likely if we don ’t change the way animals are farmed, scientists have warned.

Wild birds are being killed by highly pathogenic strains of bird flu emerging from large-scale poultry farms. Typically, these more dangerous strains develop in commercial poultry, evolving from low pathogenic viruses found in the wild.

The H5N1 virus currently circulating the globe originated in a commercial goose farm in China in 1996, spread rapidly in poultry in Asia and spilled over into wild birds in 2005. For many wild birds, already threatened by loss of habitat and climate change, the additional threat of bird flu will have a devastating impact.

Over the past 50 years, the global population of poultry has grown from six to 35 billion. “These large livestock populations, which are connected through trade, form reservoirs where infectious diseases can evolve and spill over into wildlife ” says Thijs Kuiken, professor in the department of viroscience at Erasmus University Medical Centre, Rotterdam.

Kuiken T and Cromie R. 2022. Protect wildlife from livestock diseases. Science. 378, 6615.

Where did covid come from?

Exploitation of nature, the evidence suggests

There has been endless speculation on the origins of covid, with some suggesting it came from a laboratory. This panel of experts say the evidence supports a zoonotic (from animals) origin with this spillover from wildlife to people occurring via the wildlife trade.

Wildlife farming, live animal trading and expanding livestock production are all drivers of emerging infectious diseases. In recent years, wildlife trade in Southeast Asia and southern China has exploded to an industrial scale. The authors of this report say we must employ strategies to reduce the risk of spillover and spread. They call for a One Health approach that aims to sustainably balance the health of people, animals and ecosystems.

KeuschGT,AmuasiJH,AndersonDE et al.2022.Pandemicorigins andaOneHealthapproachtopreparednessandprevention: solutionsbasedonSARS-CoV-2andotherRNAviruses. Proceedings of the National Academy of Sciences USA.119(42)e2202871119.

Meat increases risk of diabetes

…while vegans have lower rates

Eating meat increases the risk of developing diabetes, according to a study published in the journal Nutrients. They found that older Australian women who eat a vegetarian or vegan diet are less likely to have diabetes, compared to women who regularly eat meat. Those who ate meat several times a day had a significantly higher risk.

Diets high in saturated fats, refined carbohydrates and low in fibre have been linked to increased visceral (tummy) fat and a bigger waist measurement, which are both well-established risk factors for diabetes. Previous studies have reported similar findings – the Adventist studies, for example, found lifelong vegetarians have much lower rates of diabetes than meat-eaters.

Combat the cost-of-living crisis

Vegans spend less on food

Following the call from international organisations and scientists for a drastic change in dietary habits, to protect both public health and the environment, plant-based diets have been promoted worldwide. Despite this, some still claim it costs more to be vegan.

This study looked at the diets of over 1,000 people, representative of the population in Portugal, and found that plant-based consumers not only don ’t spend more but spend less than any consumer assessed. These results match those of an earlier US study that also found vegans spend less on food than meat-eaters.

PaisDF,Marques ACandFuinhasJA. 2022.Thecostof healthierand moresustainable foodchoices:Do plant-based consumersspend moreonfood? Agriculturaland FoodEconomics. 10(1)18.

Plant-based diets improve cancer prognosis

The latest evidence revealed

A review of 30 studies found that higher intakes of plant-based foods are linked to an improved prognosis for cancer survivors. A high intake of wholegrains and fibre improved outcomes in those with colorectal (bowel) cancer while a higher intake of fruit, veg and fibre, and a moderate intake of soya, benefitted those with breast cancer.

For prostate cancer, a higher vegetable fat intake was linked to improved prognosis while a high nut intake was consistently related to better outcomes for all three types of cancer.

Taken together, evidence shows how healthy and unprocessed plant-based foods, including wholegrains, nuts, fruit and vegetables, may benefit cancer prognosis.

Is drought increasing?

Hardt L, Mahamat-Saleh Y, Aune D et al. 2022. Plant-based diets and cancer prognosis: a review of recent research. Current Nutrition Reports. Epub ahead of print.

Yes – now 20 times more likely because of the climate crisis

Extreme weather events such as heatwaves, floods, storms and droughts are becoming more frequent in many parts of the world as a result of climate change.

Since the beginning of May to mid-September, five back-to-back heatwaves blanketed large swathes of Europe and monthly maximum temperature records were broken across Italy, France, Switzerland, Germany, Poland, Hungary and Slovenia. In Europe alone, there were 24,000 heat-related deaths. Parts of China and North America also suffered intense heatwaves.

The World Weather Attribution group found that the record drought of 2022 could be expected once every 20 years in today ’ s climate but only every 400 years without climate change.

WorldWeatherAttribution.2022.Hightemperaturesexacerbatedbyclimate changemade2022NorthernHemispheresoilmoisturedroughtsmorelikely.