Nutritionists have some advice for astronauts worried about bone loss: Eat more fish — and while you’re at it, skip the salt.
Studies show strong ties between how much fish astronauts eat while in orbit and the amount of bone they were able to preserve, says NASA nutritionist Scott Smith, with the Johnson Space Center in Houston.
Astronauts typically lose between 1 to 1.5 percent of their bone mass per month in orbit. A postmenopausal woman, by comparison, loses that amount of bone in a year. On Earth, the condition often leads to osteoporosis, which leaves bones susceptible to fractures and breaks.
Whether a diet rich in fish can help mitigate bone loss for the terrestrial-bound has not been determined, but Smith finds it highly likely.
Fish is a good source of protein and contains many vitamins and minerals. Aim for at least two portions a week, including at least one portion of oily fish. Oily fish is high in omega-3 fats, which may help to prevent heart disease. You can choose from fresh, frozen and canned; but remember that canned and smoked fish can be high in salt. Oily fish include salmon, mackerel, trout, herring, fresh tuna, sardines and pilchards. Non-oily fish include haddock, plaice, coley, cod, tinned tuna, skate and hake. Anyone who regularly eats a lot of fish should try to choose as wide a variety as possible.