In theory, if we eat a “healthy balanced diet” we should get all the nutrients we need to keep healthy, but recent research suggests that we are missing out on essentials. Here are tips on the best foods to include in your diet to boost your intake.

Potassium protection

In the UK, the most recent nutritional survey suggests that women average 2,653mg of the 3,500mg daily target (and men 3,367mg) of this mineral, needed to help control fluid balance in our bodies.

Researchers at Tufts University in Boston have shown recently that having a diet rich in fruit and vegetables - and thus high in potassium - may protect against the muscle-wasting that comes with age. Their study of 400 men and women over 65 found that those with a high potassium diet averaged 3.6lb more lean muscle.

Eating at least five a day of fruit and vegetables is a good place to start upping intakes. A medium baked potato has 1,134mg, a boiled parsnip about 675mg, a banana or half a papaya 400mg and an orange and a pear 240mg.

Selenium snack

This time men also need to take note as both sexes are estimated to eat about 39mcg a day. Men should aim for 75mcg and women 60mcg. We need selenium to make vital detoxing enzymes and for robust immune and reproductive systems. Snacking on four to five Brazil nuts a day will give the selenium you need.

Iron targets

Women are worse off than men, averaging 10mg a day, which falls short of the 14.8mg target. Not getting enough iron over a long period can lead to tiredness and feeling low. To boost intakes eat iron-rich foods regularly - lean red meats (3.4mg iron in a rump steak), oily fish (4.6mg in a 100g serving of canned sardines) and shellfish such as mussels and crab (3.6mg per 200mg serving and 2.8 mg in 100g respectively). Other sources include fortified breakfast cereals, dark green vegetables and dried apricots.

Vitamin D for a healthy heart

Two new studies suggest that recommended intake levels may not be high enough. Research indicates that the vitamin plays an important role in protecting against heart disease. While adults aged 19 to 50 should, in theory, make enough vitamin D in summer, over-fifties and pregnant or breast-feeding women are advised to take a daily 10mcg supplement.

If you think you aren't hitting targets for iron, selenium or vitamin D, a general, sensible multivitamin and mineral supplement could nudge you in the right direction.

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