For many people who have a healthy diet, taking supplements is commonplace and in some circles seen as just as essential as the food itself. The irony about supplements is that populations with a poor diet low in nutrient-dense food tend not to take them, whilst those who eat well do take them yet arguably have less need for them.
But take a trip to the health store and the supplements are arranged by need state - immunity, digestion, energy and so on - and this is of course very alluring. Who wouldn't want good digestion and a robust immune system? Many supplements are sold on the promise of prevention rather than cure and so one could argue that there is a reason to take them all.
But not all supplements are the same as there is more than one chemical formulation of, say, zinc. The other difference is that while some versions deliver nutrients in the same form that one would find in food, others offer a completely different form. The latter may still be labelled as, say 15mg of zinc, but how much can be absorbed differs depending on which formulation is being used.
Human beings are designed to obtain nutrients from food, obviously, but what we eat absorbs nutrition from the soil and performs a metabolic process which completely changes the structure of the nutrient into a form that is plant-bound with other compounds that then help us human (or animals) use that nutrient when we eat it. Research suggests that if we bypass this natural process, or take the nutrient in isolation rather than in the plant bound structure, the nutrient is not as effectively used, nor broken down appropriately.
The nutrients that are available that are in the superior form are often known as 'food state'. There are many examples to choose from; vitamin B12 in food state form (methylcobalamin & deoxyadenosylcobalamin) is reportedly more effective than the synthetic version, known as cobalamin. In the case of vitamin D the food state version, 1, 25 - dihydroxyvitamin, is more active than the synthetic version D 'storage' form, 25-hydroxyvitamin D.
But food state nutrients are costly to manufacture which makes the final product more expensive than synthetic versions, but the label still says zinc or vitamin D so they can look the same. That said, the synthetic versions are neither useless nor toxic when taken correctly at safe doses, and so as in all things, you get what you pay for. Bear in mind that you can get an effective multivitamin for less than a £1 a day, and as supplements only do their job when taken consistently, this is a life-long project and so cost really is a consideration.