As they ripen, bananas, apples, pears, avocados and tomatoes give off a gas called ethylene, a plant hormone that speeds up ripening in nearby fruit. To soften a rock-hard avocado or kiwi, shut it in a paper bag with a banana or an apple so the gas builds up. Conversely, keep these ethylene producers away from produce you want to last, such as lettuce and other leafy greens.
Chlorine on its own is fairly gentle. But when it combines with urine, sweat and other grime from swimmers, it forms chloramines, which cause stinging eyes and that classic 'chlorine smell'. A well-kept pool barely smells at all. Shower before you swim and never pee in the water.
Muscle mass slowly shrinks with age, putting independence at risk. But in 1990, a study had nursing home residents aged 86 to 96 train their legs for eight weeks: their strength more than doubled. Muscle responds to training at any age. Getting up from a chair without using your hands is already an exercise.