Two hours a week spent outdoors in nature linked with better health

Spending just 2 hours a week in green spaces such as parks, woodlands and fields has been linked with people feeling healthier and happier.

 Adam Vaughan

13 June 2019

Getty

The health benefits of being out in nature have been well-documented and will seem common sense to many of us, but until now no one has quantified exactly how much time might be beneficial. The magic number emerged from analysis of a survey of 20,000 people in England, who reported how long they spent in natural environments in the past week, plus their health and well-being.

While individuals who spent less than 2 hours in nature were no more likely to report good health or well-being than those who spent no time there at all, those who spent more than 2 hours had consistently higher health and well-being levels.

“It’s not a huge amount of time. You can spread it over the course of a week or seem to get it in a single dose, it doesn’t really matter,” says Mathew White at the University of Exeter, UK. Moreover, the threshold is within reach for most people: the analysis found that the average person spent 94 minutes a week exposed to a natural environment.

Green is good

“We have long known that nature is good for physical and mental health and putting numbers on the critical ‘dose of nature’ which gives us the best health is a really important step forward,” says Rachel Stancliffe of the Centre for Sustainable Healthcare in Oxford, UK.

After 2 hours, the health benefits of being out in nature seem to give diminishing returns, with a cut-off after 5 hours. White says that could be explained by many of that group being dog walkers who are out in nature with little choice in the matter. The team controlled for the fact that the health benefits might be a byproduct of physical activity, not contact with nature.

The magnitude of health gains of 2 hours spent in nature appear to be significant, on a par with the health differences associated between living in a well-off area and a deprived one. They also seem to apply to everyone, regardless of age, gender, long term illness or disability. “You don’t have to be running around the park, just sitting on a bench will do,” says White.

Initial findings from an European Union project due to be published later this year suggests 2 hours is not just the magic number for the English, says White, but all Europeans.

Journal reference: Scientific Reports, DOI: 10.1038/s41598-019-44097-3

https://www.newscientist.com/article/2206249-two-hours-a-week-spent-outdoors-in-nature-linked-with-better-health/

Many breakfast cereals still contaminated by weed killer, environmental group says

Several popular breakfast foods, including Cheerios and Nature Valley products, continue to test positive for trace amounts of a controversial herbicide that may increase the risk of cancer, according to a report released Wednesday by an environmental advocacy group.

 Arman Azad, CNN

Updated 1204 GMT (2004 HKT) June 12, 2019

The Environmental Working Group, which has links to the organics industry, found that all 21 of the products it tested had levels of glyphosate that were "higher than what EWG scientists consider protective for children's health."

Manufacturers maintain that their foods are safe, and the findings aren't unprecedented: The group also found in October that most of the breakfast cereals it tested contained glyphosate, the main ingredient in the weed killer Roundup.

The new report follows two prominent legal verdicts that determined the herbicide caused cancer in plaintiffs.

Juries say glyphosate causes cancer, award billions

A federal jury unanimously determined in March that Roundup was a "substantial factor" in causing a California man's cancer. And last month, California jurors ordered the manufacturer, Monsanto, to pay over $2 billion to a couple who said long-term exposure to the product caused their cancers.

The latter verdict is being appealed, but about 11,000 similar cases are pending in state and federal courts.

Pharmaceutical giant Bayer AG, which now owns Monsanto, maintains that its product is safe.

A spokeswoman for the company's crop science subsidiary, Charla Lord, said that an "extensive body of science" and "the conclusions of regulators around the world" show that "glyphosate-based products are safe when used as directed."

General Mills, which manufactures all of the products tested in the EWG report, said in a statement that its "top priority is food safety."

The company noted that "most crops grown in fields use some form of pesticides and trace amounts are found in the majority of food we all eat" but said it was working to "minimize the use of pesticides on the ingredients we use in our foods."

General Mills did not directly respond when asked why it is reducing pesticide use when it already considers its products to be safe.

How much glyphosate is too much?

An analysis published in February found that glyphosate can increase cancer risk by up to 41%, although the researchers focused on those with the "highest exposure" to the chemical, like groundskeepers, who are exposed to more glyphosate than people may consume through snacks.

The herbicide can make its way into processed foods after being used on farms that grow oats, but none of the levels found in any food products in the new report exceeded the Environmental Protection Agency's legal limits.

"It is not surprising that very low levels of pesticides, including glyphosate, are found in foodstuff," said Dr. Paolo Boffetta, associate director for population sciences at Mount Sinai's Tisch Cancer Institute. "In general, these levels are unlikely to cause health effects in consumers."

Still, "it is important that people know whether there is glyphosate or other chemicals in their food, even at very low levels," said Boffetta, who was not involved in the reports or the analysis.

General Mills emphasized in its statement that it followed "strict rules" set by "experts at the [Food and Drug Administration] and EPA." Bayer's Lord said "the reality is that regulatory authorities have strict rules when it comes to pesticide residues, and the levels in this report are far below the established safety standards."

The Environmental Working Group, however, uses a far more conservative health benchmark that includes an added buffer for children, as "exposure during early life can have more significant effects on development later in life," said Dr. Alexis Temkin, an EWG scientist who co-authored both reports and spoke to CNN last year.

Manufacturers dispute that threshold. In an October statement, General Mills said that "the extremely low levels of pesticide residue cited in recent news reports is a tiny fraction of the amount the government allows."

The EPA said in April that the proper use of glyphosate poses "no risks to public health" and that the chemical "is not a carcinogen," a cancer-causing chemical. But a World Health Organization agency, the International Agency for Research on Cancer, determined in 2015 that glyphosate is "probably carcinogenic to humans."

A separate WHO panel assessing pesticide residues said in 2016 that "glyphosate is unlikely to pose a carcinogenic risk to humans from exposure through the diet," adding to a dizzying array of contradictory findings, but the International Agency for Research on Cancer has vigorously defended its conclusion.

The agency wrote in 2018 that it "has been subject to unprecedented, coordinated efforts to undermine the evaluation, the program and the organization." Those attacks, it said, "have largely originated from the agro-chemical industry and associated media outlets."

A war of words

A 2017 CNN investigation of internal emails from Monsanto appeared to show company executives attempting to discredit the International Agency for Research on Cancer report before it was even released.

One executive's email, titled "RE: IARC planning," suggested that the company ghostwrite parts of a 2015 study in which experts rejected the agency's finding that glyphosate could cause cancer. A Monsanto spokeswoman told CNN at the time that the study was not ghostwritten and was "the work of the glyphosate expert panel."

Although the EPA has maintained that glyphosate is safe, CNN's investigation also raised questions about industry influence at the federal agency.

A Monsanto executive wrote in a 2015 internal company email, for example, that an EPA official offered to help quash another agency review of glyphosate, saying, "If I can kill this I should get a medal."

The company has denied any undue influence over regulators. And its parent company, Bayer Crop Science, criticized the Environmental Working Group in its recent statement to CNN. "The group behind the new report has a long history of spreading misinformation about pesticide residues," spokeswoman Lord said.

EWG, a nonprofit organization based in Washington, denied those allegations. Bayer's criticism "must be taken with a grain of salt," EWG President Ken Cook said in a statement. In light of lawsuits, he said, Bayer was "desperate to continue hiding the truth."

Though it maintains that it is an independent organization, EWG acknowledges support from the organics industry, stating that its "corporate partners for general support and events" include Organic Valley and Stonyfield Farms. Foods labeled organic may not be grown with most synthetic substances, including glyphosate.

The group also has a "shared services agreement" with the Organic Voices Action Fund, a nonprofit organization funded by companies such as Nature's Path and Annie's -- both of which make cereal.

https://edition.cnn.com/2019/06/12/health/glyphosate-cereals-ewg-study/index.html

Farmed salmon is now a staple in diets – but what they eat matters too

Salmon is not only tasty but is prized for being low fat and high in rich omega-3 oils. In recent times, salmon has been a staple of the national diet, so much so that wild salmon has given way to a huge global farmed industry, worth US$15.4 billion. 

June 12, 2019 12.59am AEST

Salmon are farmed in net pens suspended from floating collars in the sea. Like other types of farming, quality varies and the industry has sometimes come in for criticism over the health and welfare of fish.

Given the size of the market, criticisms have included the amount of wild fish it takes to rear one salmon – if you’re eating farmed salmon for sustainability reasons, for example, you might worry that it takes 1.3kg of wild feed to produce one kilogramme of salmon.

Environmental campaigners have long made the case that the growth of cage farming salmon results in a net loss of fish because they are fed “marine ingredients”, which includes fishmeal (rendered down low-value fish) and increasingly, processing offcuts from the fishery industry – fish oil that is pressed out of the same fish and more specialised high-value protein ingredients.

But this aquaculture as a whole is a net producer of marine ingredients. Carps – which make up by far the largest proportion of global aquaculture – are fed diets with little or no marine ingredients. Sometimes they are even cultured using no feed at all, instead relying on the natural productivity of ponds, encouraged by fertilisation. Advances in nutrition, together with a rising price, has also led to a decline in the levels of marine ingredients fed to salmon, with protein and oils replaced by vegetable substitutes such as soy and rapeseed oil.

A commercial fish farm. Ranko Maras/Shutterstock

Between the 1970s and 1990s there was a peak in production of “marine ingredients” – used in trans-fats for margarines, and meals for a wide range of livestock, especially pigs and chickens. But as aquaculture grew fast, more of the global supply of fishmeal and oil was directed to feeding farmed fish and shrimp – an increasingly lucrative market. In 2010, aquaculture was taking around 75% of the global supply.

But the rapid growth in demand for marine ingredients coupled with fluctuating supplies led to price hikes that stimulated the development of alternatives. Comparatively little is now used for pig and chicken diets as companies have become more strategic with their use.

But marine ingredients are still important in maintaining the health of fish in aquaculture, especially in early development. And in the case of salmon, they are important in maintaining the quality of the fish, which provide consumers with high levels of omega-3 fatty acid. Indeed, the fastest growth in marine ingredients sales are for high omega 3 oily capsules, taken as dietary supplements.

Finding alternatives

As farmed fish gets relatively cheaper but the price of marine ingredients to feed them continues to climb, the pressure to find alternatives is likely to continue.

Various plant sources such as processed soy and wheat products have emerged as major substitutes for fishmeal but as much of this has to be imported, local alternatives such as field beans are being researched and trialled in Europe. Outside of Europe, it is still very common to use byproducts from livestock production to feed farmed fish in aquaculture diets such as poultry byproducts, which are regarded as a highly nutritious and cheap protein resource.

Replacing marine oils – which are the only source of long chain omega-3 fatty acids – is a bigger challenge. Initiatives such as GM Camelina, a “transgenic” vegetable oil crop created by transplanting marine plankton genes into oil-seed rape, and which could help cut use of marine ingredients as feed, is likely to remain an issue given public acceptance of genetically modified organisms (GMOs).

Major fish stocks used to produce marine ingredients, however, are now subject to much more intense scrutiny, as are the fish farms that use the feeds, which is leading to both better efficiency and practice.

Trout also farmed. Kosin Sukhum/Shutterstock

The Marine Ingredients Association itself has introduced a certification system for fisheries that produce marine ingredients, and the eco and social certification of farms has created competing bodies such as the Global Aquaculture Alliance and the WWF-inspired Aquaculture Stewardship Council, whose own independent certification schemes have reducing marine ingredients as a central theme.

The use of byproducts from sustainable fisheries is also encouraged by all major certification schemes. It is estimated that over a third of the global fishmeal and fish oil supply now comes from byproducts such as herring and other oily fish trimmings.

The potential for increasing the proportion of marine ingredients from these sources is substantial. More than half of a fish often becomes byproduct, and much of this is often wasted. There is also an increased trend towards processed fish in regions, such as in Asia, that have generally preferred to buy whole fish. As demand for farmed fish grows alongside the pressure to limit wild catches, these byproducts will increasingly be required.

A combination of market forces, self-regulation and engagement by environmental groups supports the evolution towards more sustainable aquaculture and better managed fisheries. And it is increasingly something consumers can look out for when they are buying fish. Technologies such as Blockchain, linked to QR codes, and databases accessible through apps, will increasingly allow consumers to dig down into ever more detail of how their food is produced.

http://theconversation.com/farmed-salmon-is-now-a-staple-in-diets-but-what-they-eat-matters-too-53546