Most male fin and blue whales sing at around 17 to 18 hertz, which is too deep for humans to hear, but the 'lonely' whale communicates at 52 hertz. When more recordings were released in the nineties, Dr Watkins studied the 52 hertz whale more closely.
The average person needs to absorb just a small amount of iron each day to stay healthy (around 1 mg for adult males and 1.5 mg for menstruating females). To achieve this, however, we need to consume several times that amount. This is because our bodies absorb only a fraction of the iron contained in the foods we eat.
Generally, men and non-menstruating women should receive about 10 mg of iron daily, menstruating or nursing women 15 mg, and pregnant women 30 mg daily. You can quickly learn how much iron you are consuming in your diet by using our Food Advisor. Iron is one of the nutrients that the body cannot easily dispose of when intake is excessive, so excess iron is instead stored in vital organs and blood cells.