Health news: Amount of exercise matters, not frequency

Here's a round-up of the latest findings across an array of pressing health issues.

A new study by researchers at Queen’s University has determined that adults who accumulated 150 minutes of exercise on a few days of the week were not any less healthy than adults who exercised more frequently throughout the week.

Ian Janssen and his graduate student Janine Clarke studied 2,324 adults from across Canada to determine whether the frequency of physical activity throughout the week is associated with risk factors for diabetes, heart disease and stroke.

“The findings indicate that it does not matter how adults choose to accumulate their 150 weekly minutes of physical activity,” Dr. Janssen said.

“For instance, someone who did not perform any physical activity on Monday to Friday but was active for 150 minutes over the weekend would obtain the same health benefits from their activity as someone who accumulated 150 minutes of activity over the week by doing 20-25 minutes of activity on a daily basis,” he said.

Physical activity was measured continuously throughout the week by having research participants wear accelerometers on their waists.

Accelerometers are tiny electrical devices (about the size of a small package of matches) that record how much a person moves every minute.

The research is published in the journal Applied Physiology, Nutrition and Metabolism.

ANI

Men who lose sleep during the work week may be able to lower their risk of developing Type 2 diabetes by getting more hours of sleep, a new study has revealed.

The research conducted by Los Angeles Biomedical Research Institute has found that  insulin sensitivity, the body''s ability to clear glucose (blood sugar) from the bloodstream, significantly improved after three nights of "catch-up sleep" on the weekend in men with long-term, weekday sleep restrictions.

The study lead by author Peter Liu, provides information about people who lose sleep during the week - often because of jobs and busy lifestyles - but "catch up" on their sleep on the weekends.

Liu and researchers from the University of Sydney in Australia studied 19 non-diabetic men, with an average age of 28.6 years, who for six months or longer (average, 5.1 years) self-reported inadequate sleep during the workweek.

It was found that on average, the men received only 6.2 hours of sleep each work night. But they regularly caught up on their sleep on the weekends, sleeping an extra 37.4 percent, or 2.3 hours, per night.

The research was presented at The Endocrine Society''s 95th Annual Meeting in San Francisco.

ANI

Fruits and vegetables should not be stored in the fridge or a dark cupboard because they need a natural cycle of day and night to produce maximum levels of nutrients and flavour, a new study has claimed.

The fruits and vegetables we buy in the grocery store are actually still alive, and it matters to them what time of day it is, the study found.

This suggests that the way we store our produce could have real consequences for its nutritional value and for our health.

Allowing fruits and vegetables to continue on a day-night cycle keeps them in a more natural and healthy state while permanent darkness or light may affect their nutrient content for the worse, researchers found, The Telegraph reported.

"Vegetables and fruits, even after harvest, can respond to light signals and consequently change their biology in ways that may affect health value and insect resistance," said Janet Braam of RiceUniversity in US.

"Perhaps we should be storing our vegetables and fruits under light-dark cycles and timing when to cook and eat them to enhance their health value," Braam said.

Braam and her colleagues earlier found that plants grown in the laboratory change their physiology in important ways over the course of the day, driven by circadian rhythms.

They suspected that food crops would do something similar, perhaps even after they'd been harvested from the field.

Unlike animals, plants are made up of many separate parts or modules - leaves and branches, fruits and roots - that can continue to metabolise and survive more or less independently, at least for some time. Even after they've been harvested and cut from one another, their cells remain active and alive.

Braam's team now shows that post-harvest vegetables and fruits can in fact continue to perceive light and, as a result, their biological clocks keep on ticking.

That's an advantage to the plants because it allows them to alter levels of important chemicals that protect them from being eaten by insects and other herbivores, the researchers found.

The researchers made the initial discovery in studies of cabbage. They then went on to show similar responses in lettuce, spinach, zucchini, sweet potatoes, carrots, and blueberries.

Fruits and veggies subjected to light-dark cycles at the right times clearly suffered less insect damage.

It might be time to consider our foods' daily schedules, not just our own, when deciding what time to have dinner. If that's too much to ask, maybe there is another way, according to the researchers.

"It may be of interest to harvest crops and freeze or otherwise preserve them at specific times of day, when nutrients and valuable phytochemicals are at their peak," Braam said.

The study was published in the journal Current Biology.

PTI

Moms-to-be who take iron daily during pregnancy can significantly increase their babies' birth weight, a new research has found.

Iron deficiency is the most widespread nutritional deficiency in the world. It is the most common cause of anaemia during pregnancy, especially in low and middle income countries, affecting an estimated 32 million pregnant women globally in 2011.

Researchers in the UK and US analysed the results of over 90 studies (a mix of randomised trials and cohort studies) of prenatal iron use and prenatal anaemia, involving nearly two million women.

Iron use increased a mother's average haemoglobin levels compared with controls and significantly reduced the risk of anaemia, found the study published in bmj.com.

The effects were seen for iron doses up to 66 mg per day. The World Health Organisation currently recommends a dose of 60 mg per day for pregnant women.

The study found no reduction in risk of preterm birth as a result of iron use. However analysis of cohort studies showed a significantly higher risk of low birth weight and preterm birth with anaemia in the first or second trimester of pregnancy.

Further analysis indicated that for every 10 mg increase in iron dose per day (up to 66 mg per day), risk of maternal anaemia was 12 per cent lower, birth weight increased by 15 g and risk of low birth weight decreased by 3 per cent.

"Our findings suggest that use of iron in women during pregnancy may be used as a preventive strategy to improve maternal haematological status and birth weight," authors said.

PTI

US authorities have approved over-the-counter sale of a morning-after pill for all women of child-bearing potential, lifting age limits on the emergency contraceptive.

The US Food and Drug Administration (FDA) announced it has approved the use of Plan B One-Step (levonorgestrel) as a nonprescription product for all women of child-bearing potential.

This action complies with the April 5, 2013 order of the United States District Court in New York to make levonorgestrel-containing emergency contraceptives available as an over-the-counter (OTC) product without age or point-of-sale restrictions.

Plan B One-Step is an emergency contraceptive intended to reduce the chance of pregnancy following unprotected sexual intercourse or a known or suspected contraceptive failure.

Plan B One-Step is a single-dose pill (1.5 mg tablet) that is effective in decreasing the chance of pregnancy and should be taken as soon as possible within three days after unprotected sex, FDA said in a statement.

On June 10, 2013, the agency notified the Court of its intent to comply with it's April 5, 2013 order instructing the FDA to make levonorgestrel-containing emergency contraceptives available as an over-the-counter (OTC) product without age or point-of-sale restrictions.

To comply, the FDA asked Teva Women's Health, the manufacturer of Plan B One-Step, to submit a supplemental application seeking approval of the one-pill product to be made available without any restrictions.

"Over-the-counter access to emergency contraceptive products has the potential to further decrease the rate of unintended pregnancies in the United States," said Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research.

Plan B One-Step was first approved in July 2009 for use without a prescription for women aged 17 and older and as a prescription-only option for women younger than age 17.

With this approval, the product is now available without a prescription for use by all women of reproductive potential.

The product contains higher levels of a hormone found in some types of daily use oral hormonal contraceptive pills and works in a similar way to these contraceptive pills by stopping ovulation and therefore preventing pregnancy.

According to FDA, some women taking Plan B One-Step have reported experiencing side effects such nausea, vomiting, stomach pain, headache, dizziness and breast tenderness, similar to the side effects of regular prescription-only birth control pills.

PTI