Week 34 of pregnancy reduces breast cancer risk: study

Kosovan girls dressed as ballet dancers hold roses and perform in front of the National Theatre on October 10, 2018 during the International Breast Cancer Awareness Month, to raise awareness on breast cancer and to promote prevention. (AFP)
Updated 24 October 2018
0

Week 34 of pregnancy reduces breast cancer risk: study

  • The link between pregnancy and breast cancer risk reduction is well known among medical researchers, who have suggested breast cells fundamentally alter their composition when a woman first falls pregnant and they prepare to produce milk

PARIS: Women’s bodies undergo a “striking” change during a specific week of pregnancy that can significantly reduce their risk of developing breast cancer later in life, scientists said Tuesday.
Previous research has highlighted how women under the age of 30 can reduce their risk of contracting breast cancer later in life by having a baby.
But a new study by experts in Denmark and Norway claims to have identified the precise week of pregnancy when the change occurs.
“If you deliver a child at week 33 you get the child, which is great, but you don’t get the bonus of having a lower risk of breast cancer for the rest of your life,” Mads Melbye, from the University of Copenhagen’s Department of Clinical Medicine and lead study author, told AFP.
“It’s a very distinct change in risk when you go from week 33 to week 34.”
A typical pregnancy lasts 40 weeks and a baby born before 37 weeks is considered premature.
Melbye and his team studied a huge database of nearly four million women in Denmark and Norway stretching back almost 40 years.
It listed the age at which each of them gave birth, how far into a pregnancy each birth occurred and whether or not they contracted breast cancer later in life.
They found that women who gave birth after 34 weeks had an average 13.6 percent lower risk of developing breast cancer compared to women who had no children.
For pregnancies that ended a week earlier, the reduction in risk — while still there — was only 2.4 percent.
Melbye said what changes in women during this vital week of gestation remains a mystery.
“We don’t know what that is, but knowing that you have to get to this point of the pregnancy makes it much easier for researchers to focus because we have to know what happens around that week to understand this,” he said.
He said it may be possible a woman’s body sends a signal after 34 weeks of pregnancy to boost immunity against environmental causes of breast cancer.
“To the best of our knowledge it must have something to do with a specific biological effect that the cells reach at 34 weeks.”

The link between pregnancy and breast cancer risk reduction is well known among medical researchers, who have suggested breast cells fundamentally alter their composition when a woman first falls pregnant and they prepare to produce milk.
But Melbye and his team found that a second or third pregnancy of at least 34 weeks reduced the risk of breast cancer even further.
This held true even in women who experienced stillbirths after 34 weeks, meaning the change is unlikely to be linked to breastfeeding.
Authors of the study, published in the journal Nature Communications, said it would allow scientists to better probe the link between pregnancy and breast cancer risk by focusing on a narrow window during which the “striking” change occurs.
Although the reduction of risk is dramatic, there’s a catch: researchers found that the additional protection against breast cancer only comes in women under 30.
“It’s not only the first childbirth; every childbirth has its own reduction in breast cancer risk but there’s a trick to this: You have to have your kids before you turn 29,” said Melbye.
“Because after that age there’s no extra bonus in breast cancer risk (reduction).”


Human diet causing ‘catastrophic’ damage to planet: study

Updated 51 min 5 sec ago
0

Human diet causing ‘catastrophic’ damage to planet: study

PARIS: The way humanity produces and eats food must radically change to avoid millions of deaths and “catastrophic” damage to the planet, according to a landmark study published Thursday.
The key to both goals is a dramatic shift in the global diet — roughly half as much sugar and red meat, and twice as many vegetables, fruits and nuts, a consortium of three dozen researchers concluded in The Lancet, a medical journal.
“We are in a catastrophic situation,” co-author Tim Lang, a professor at the University of London and policy lead for the EAT-Lancet Commission that compiled the 50-page study, told AFP.
Currently, nearly a billion people are hungry and another two billion are eating too much of the wrong foods, causing epidemics of obesity, heart disease and diabetes.
Unhealthy diets account for up to 11 million avoidable premature deaths every year, according to the most recent Global Disease Burden report.
At the same time the global food system is the single largest emitter of greenhouse gases, the biggest driver of biodiversity loss, and the main cause of deadly algae blooms along coasts and inland waterways.
Agriculture — which has transformed nearly half the planet’s land surface — also uses up about 70 percent of the global fresh water supply.
“To have any chance of feeding 10 billion people in 2050 within planetary boundaries” — the limits on Earth’s capacity to absorb human activity — “we must adopt a healthy diet, slash food waste, and invest in technologies that reduce environmental impacts,” said co-author Johan Rockstrom, director of the Potsdam Institute for Climate Change Impact Research.

“The great food transformation”
“It is doable but it will take nothing less than global agricultural revolution,” he told AFP.
The cornerstone of “the great food transformation” called for in the study is a template human diet of about 2500 calories per day.
“We are not saying everyone has to eat in the same way,” Lang said by phone. “But broadly — especially in the rich world — it means a reduction of meat and dairy, and a major increase in plant consumption.”
The diet allows for about seven grams (a quarter of an ounce) of red meat per day, and up to 14. A typical hamburger patty, by comparison, is 125 to 150 grams.
For most rich nations, and many emerging ones such as China and Brazil, this would represent a drastic five-to-ten-fold reduction.
Beef is the main culprit.
Not only do cattle pass massive quantities of planet-warming methane, huge swathes of carbon-absorbing forests — mostly in Brazil — are cut down every year to make room for them.
“For climate, we know that coal is the low-hanging fruit, the dirtiest of fossil fuels,” said Rockstrom. “On the food side, the equivalent is grain-fed beef.”
It takes at least five kilos of grain to produce a kilo of meat.
And once that steak or lamb chop hits the plate, about 30 percent will wind up in the garbage bin.
Dairy is also limited to about one cup (250 grams) of whole milk — or its equivalent in cheese or yoghurt — per day, and only one or two eggs per week.

“Eat more legumes and veggies”
At the same time, the diet calls for a more than 100 percent increase in legumes such as peas and lentils, along with vegetables, fruits and nuts.
Grains are considered to be less healthy sources of nutrients.
“We can no longer feed our population a healthy diet while balancing planetary resources,” said The Lancet editor-in-chief Richard Horton.
“For the first time in 200,000 years of human history, we are severely out of sync with the planet and Nature.”
The report drew heavy fire from the livestock and dairy industry, and some experts.
“It goes to the extreme to create maximum attention, but we must be more responsible when making serious dietary recommendation,” said Alexander Anton, secretary general of the European Dairy Association, noting that dairy products are “packed” with nutrients and vitamins.
Christopher Snowdon of the Institute of Economic Affairs in London said the report “reveals the full agenda of nanny-state campaigners.”
“We expected these attacks,” said Lang. But the same food companies pushing back against these findings realize that they may not have a future if they don’t adapt,” he said.
“The question is: does this come by crisis, or do we start planning for it now.”
Some multinationals responded positively, if cautiously, to the study.
“We need governments to help accelerate the change by aligning national dietary guidelines with healthy and sustainable requirements, and repurposing agricultural subsidies,” the World Business Council for Sustainable Development said in a statement.