Tag: levels

Sci&Tech

American Honey Still Contains Radioactive Fallout From Nuclear Tests Decades Ago

Traces of radioactive fallout from nuclear tests in the 1950s and 1960s can still be found in American honey, new research reveals.The radioactive isotope identified, cesium-137, falls below levels considered to be harmful – but the amounts measured nonetheless emphasize the lingering persistence of environmental contaminants in the nuclear age, even a half-century after international bomb tests ended.  "There was a period in which we tested hundreds of nuclear weapons in the atmosphere," lead researcher Jim Kaste, an environmental geochemist at William & Mary university in Williamsburg, Virginia, explained last year in comments about the research."What that did was put a blanket of these isotopes into the environment during a very narrow time window."One of those isotopes was cesium-...
Sci&Tech

Technology Really Is Changing Human Circadian Rhythms, Scientists Say

We haven't been dependent on natural light from the Sun since the invention of the light bulb in 1879.Nowadays, many people spend most of the day not just in artificially lit rooms but also looking at screens – phones, computers, and TVs. Recently, there have been concerns that looking at bright screens in the evening can confuse your circadian rhythm, which is the internal clock that regulates our sleep-wake cycle.  We would assume that this means using a screen before bed might make it harder to fall asleep. In fact, there are many products you can buy to filter out the blue light from your screens, which promise to improve your sleep quality.Do these products actually work? Does screen light change our circadian rhythm, and does this make it harder to fall asleep? The story is quite co...
Sci&Tech

Feeling Hungry All The Time? Scientists Have a New Explanation For What's Going On

The interplay between blood sugar and appetite appears to be more complex than scientists realized, with new research showing that glucose levels in the blood even several hours after eating can still have a pronounced effect on how hungry people get later in the day.  Specifically, the new findings reveal that some people are prone to experiencing 'sugar dips' up to four hours after eating their last meal – a delayed glycemic response that turns out to be a more accurate indicator of appetite (and energy consumption) than glucose levels following meals."It has long been suspected that blood sugar levels play an important role in controlling hunger, but the results from previous studies have been inconclusive," says nutrition scientist Sarah Berry from King's College London."We've now sho...
Sci&Tech

Earth Nearly Lost All Oxygen And Could Have Suffocated 2.3 Billion Years Ago

Earth's transition to permanently hosting an oxygenated atmosphere was a halting process that took 100 million years longer than previously believed, according to a new study.When Earth first formed 4.5 billion years ago, the atmosphere contained almost no oxygen. But 2.43 billion years ago, something happened: Oxygen levels started rising, then falling, accompanied by massive changes in climate, including several glaciations that may have covered the entire globe in ice.   Chemical signatures locked in rocks that formed during this era had suggested that by 2.32 billion years ago, oxygen was a permanent feature of the planet's atmosphere.But a new study delving into the period after 2.32 billion years ago finds that oxygen levels were still yo-yoing back and forth until 2.22 billion year...
Sci&Tech

Unwanted Weight Change During The Pandemic? Your Stress Hormones Could Be to Blame

If you have experienced unwanted weight gain or weight loss during the pandemic, you are not alone. According to a poll by the American Psychological Association, 61 percent of US adults reported undesired weight change since the pandemic began.  The results, released in March 2021, showed that during the pandemic, 42 percent of respondents gained unwanted weight – 29 pounds (13.2 kgs) on average – and nearly 10 percent of those people gained more than 50 pounds. On the flip side, nearly 18 percent of Americans said they experienced unwanted weight loss – on average, a loss of 26 pounds (11.8 kgs).Another study, published on 22 March 2021, assessed weight change in 269 people from February to June 2020. The researchers found, on average, that people gained a steady 1.5 pounds (0.7 kgs) pe...
Sci&Tech

More Than 4,000 Blood Tests Suggest Our Bodies Age in 3 Distinct Shifts

In terms of biological aging, the body seems to shift gears three times during our lifespans, research from 2019 suggests – with 34 years, 60 years, and 78 years being the key thresholds.  In other words, there's evidence that aging isn't one long, continuous process that moves at the same speed throughout our lives.The findings might help us understand more about how our bodies start to break down as we get older, and how specific age-related diseases – including Alzheimer's or cardiovascular disease – could be better tackled.The same study has also put forward a new way of reliably predicting people's ages using the protein levels (the proteome) in their blood."By deep mining the aging plasma proteome, we identified undulating changes during the human lifespan," the researchers wrote in...