You could have a hair mineral analysis as a gage of your current minerals. If you suffer from cramps you could have magnesium deficiency. If you are quite thin and struggle to gain weight you could have sluggish liver and low stomach acid, therefore leading to imbalance of mineral absorption. If you have an acidic diet your body constantly loses calcium leading to arthritic problems and prominent joints / constipation. You could try a urine ph or salive ph test, or live blood test you can detect your body's acid/alkalinity. Then raise your alkalinity by eating an alkaline enriching diet, practice deep breathing and avoid polluted and stressful environments.
With regard to mineral balance, generaly if your eating some organic vegetables during the day you get enough salt, but trace minerals you can get from adding 1/4 tsp of something like Sea Salt or preferably himalayn pink salt to every 2 litres of water. Everybody is different, so you its wise to experiment with different tests. Your blood type / ayurvedic / astrological planets, diet and lifestyle can all have an influence on your mineral balance.