Mixing lettuce varieties could help provide protection against the chain reactions of free radicals, molecules that can cause cell damage and generate various diseases, suggests a study.

The findings, published in the Journal of Agricultural and Food Chemistry, said that mixing lettuce, one of the indispensable vegetables in the Mediterranean diet, could be a good idea as not all lettuce varieties have the same antioxidant effect.

The researchers from the University of the Basque Country (UPV/EHU) in Spain and the University of Pisa in Italy analysed the compounds of three lettuce varieties: the green-leaf 'Batavia', the semi-red-leaf 'Marvel of Four Seasons', and the red-leaf 'Oak Leaf'.

Using Electron Paramagnetic Resonance (EPR) techniques, they were able to observe the behaviour of the speed (kinetics) of the antioxidant compounds of each variety.

The results showed that the green-leaf lettuce contains water-soluble, antioxidant compounds that act at a slow and intermediate speed, the red-leaf one has compounds with intermediate and rapid kinetics, and the semi-red-leaf one has three kinds of compounds, with a rapid, intermediate and slow speed.

"The fact that there are compounds that act at different speeds does not mean that some are better or worse than others," said Usue Perez-Lopez, researcher at UPV/EHU.

It is also important that our bodies should acquire foods with antioxidants that have slower kinetics so that the latter will continue to act over a longer period of time.

"That is why people say that it is very interesting to mix different types of lettuce because they have different, complementary characteristics," Perez-Lopez added.

Free radicals harm our body by causing, in the best of cases, ageing and, in the worse, serious diseases.

Lettuce is rich in antioxidants, as it contains compounds like phenolic acids, flavonoids, anthocyanins, and vitamins A and C, among other things, the researchers said.

A new survey has suggested that women should do regular exercise as physical inactivity is the biggest risk factor for heart disease in women over the age of 30.

The Heart Foundation survey on the exercise habits, found that 24 per cent of male students did 60 minutes or more of exercise a day, compared to 11 per cent of females, News.com.au reported.

Trevor Shilton, Heart Foundation spokesman said that women who exercise enough to cause sweating or a faster heart beat for 30 minutes five times a week, were up to 35 per cent less likely to suffer from heart disease, strokes or blood clots.

Shilton added that there were certain times in a woman's life like in late teens and after having children when she went through more at risk of cutting out exercise due to study and work pressures.

Developing countries are pumping livestock full of antibiotics at such a startling rate that they are dramatically increasing the risk of creating drug-resistant "super bugs", scientists warned on Monday.

Antibiotic use in animals is expected to surge by two thirds globally between 2010 and 2030, while doubling in emerging giants like China, Brazil, India and Russia, according to a Princeton University study.

It warned that the practice is pushing us closer to a time when common infections could become a death sentence because they will no longer respond to drugs.

Consumption of meat, milk and eggs is growing fast in many developing and middle-income countries.

Urbanisation, increased wealth and changing diets mean industrial livestock producers are expanding rapidly.

They are relying on antibiotics to keep disease at bay in the short-term, said co-author Tim Robinson, a scientist with the International Livestock Research Institute (ILRI).

But the systematic use of low doses on livestock is creating "perfect conditions to grow resistant bacteria", he told the Thomson Reuters Foundation.

Bacteria like E. coli and salmonella are already becoming resistant to antibiotics, Robinson said, increasing fears that these diseases will endanger humans.

Passed from animals to people through food contamination, direct contact or the broader environment, antibiotic resistant bacteria will make it harder for doctors to treat basic infections or other ailments, he said.

The study by experts from Princeton, ILRI and the National Institutes of Health is the first to measure global antibiotic consumption by livestock.

Asia is the main region of concern as this is where demand for livestock products is growing dramatically while regulations governing antibiotic use in animals are either non-existent or not publicly available, scientists say.

China`s livestock industry alone could soon be consuming nearly one third of the world`s antibiotics.

The five countries with the largest projected increases in antibiotics consumption are Myanmar (205 percent), Nigeria (163 percent), Peru (160 percent) and Vietnam (157 percent).

Increasing food production for the estimated 805 million people who go to bed hungry every night will require a new approach that is less reliant on intensive, antibiotic-fuelled breeding, Robinson said.

"Poor livestock producers aren`t responsible for this problem, it`s the big firms rushing to meet demand in the growing cities," he added.

But the poor will be worst affected if resistant bacteria transfer to humans more often, he said, because they will be the least able to afford the bigger and more frequent doses of drugs required to fight infections.

A new book has observed that emotions can dictate how you eat and also demonstrates what kind of eater one is.

Hypnotherapist Marisa Peer in her new book suggests that there are different kinds of eaters like one can be an emotional eater or a habitual eater or a destructive eater or an angry eater, the Daily Express reported.

Emotional eaters find temporary relief from loneliness, boredom and sadness when they fill their stomachs with refined carbohydrates. The feeling of fullness from eating soft, sweet foods such as cake and ice cream leads to a temporary feeling of satisfaction and calmness.

Habitual eaters will eat whenever they are given the opportunity, without being aware of whether they are actually hungry.

Destructive eaters often feel uncomfortable if they are not in control of their own eating, whereas, angry eaters like crunchy or chewy foods because they find chewing hard helpful when they are feeling tense or wound up.

A new study has revealed that eating at the right time is as important as what the person is eating in order to maintain a healthy heart.

Researchers at San Diego State University and the Salk Institute for Biological Studies found that by limiting the time span during which fruit flies could eat, they could prevent aging-and diet-related heart problems.

The researchers also discovered that genes responsible for the body's circadian rhythm are integral to this process, but they're not yet sure how.

Previous research has found that people who tend to eat later in the day and into the night have a higher chance of developing heart disease than people who cut off their food consumption earlier.

The researchers also sequenced the RNA of the flies at various points in the experiment to find which of their genes had changed as a result of time-restricted feeding.

They identified three genetic pathways that appear to be involved: the TCP-1 ring complex chaperonin, which helps proteins fold; mitochondrial electron transport chain complexes (mETC); and a suite of genes responsible for the body's circadian rhythm.

Girish Melkani, a biologist at SDSU whose research focuses on cardiovascular physiology was optimistic that the results could one day translate into cardiac- and obesity-related health benefits for humans.

The study is published in Science.