According to scientists at the Karolinska Institutet in Sweden, a compound found naturally in spinach may have a powerful effect on muscle strength.

The study found that mice supplied with 'nitrate' in their drinking water developed significantly stronger muscles, than those who were not.


"From a nutritional perspective our study is interesting because the amount of nitrate that affected muscle strength in mice was relatively low," said Dr Andrés Hernández, researcher at the Department of Physiology and Pharmacology in a statement.

"Translated to humans it means that we can obtain the equivalent volume by eating more of a vegetarian diet, as nitrate is found naturally in several leafy vegetables, especially in beetroot juice, for example. There are currently no dietary supplements containing nitrate."


According to a statement, the researchers located that the 'nitrate mice' had a higher concentration of two different proteins in their muscles.

These two proteins, CASQ1 and DHPR, are involved in the homeostasis of calcium, a critical determinant of muscle contraction.

Future research will concentrate on how such a link could be explored further and practically applied to aid people with muscle weakness.

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    Spread peanut butter on wholemeal toast or crackers as a protein-rich snack. Peanuts are an excellent source of protein, with one tablespoon containing about four grams of protein.

  • Cottage Cheese

    A half cup of cottage cheese contains around 16 grams of protein, yet only has 102 calories and two grams of fat, as opposed to other cheese, where the protein benefits are counteracted by the high fat content. If you're not too keen on the cheesy taste, add a handful of berries or fruit to the bowl, or spread it on a wholemeal cracker for a savoury snack.

  • Egg Whites

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  • Tuna

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  • Lentils

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  • Nuts

    A handful of raw, unsalted nuts, like almonds, hazelnuts, walnuts are great snacks to keep handy throughout the day. You only need a small handful for your daily allowance on these, but they are high in fiber, protein, and "good" fats.