To answer this question, you need to consider the reason why one might require a daily supplement.

Firstly, it’s important to state that supplements shouldn’t be intended to be a food substitute because they can’t replicate all of the nutrients and benefits of whole foods, such as fruits and vegetables. Therefore, depending on your situation, lifestyle and your eating habits, dietary supplements may not be worth the expense.

Evolutionary speaking, humans are adapted to getting nutrients from food, and foods contain many natural chemicals and enzymes required to absorb those nutrients. However, even if you have a healthy diet with a large variety of food choices, there are some nutrients that are difficult to obtain such as vitamin D and magnesium. Therefore, supplementing with these nutrients, indefinitely may be necessary for some. Other nutrients that may require supplementation for “maintenance”, depending on your diet and health requirements, include vitamin A, vitamin K2, selenium, iodine and vitamin C.

The benefits of whole foods over dietary supplements include:

  • Greater nutrition – Supplements can’t supply all the nutrients in food. Whole foods are complex, containing a variety of the micronutrients and phytonutrients your body needs — not just one. When you isolate nutrients from a food you lose these benefits. For example, an orange provides vitamin C plus some beta carotene, calcium, fibre and antioxidants. If you take a vitamin C supplement you miss out on all the additional benefits.
  • Essential fibre –Whole foods, such as whole grains, fruits, vegetables and legumes, provide dietary fibre. Most high-fibre foods are also packed with other essential nutrients. Dietary fibre is vital for good gut health and can help prevent chronic diseases, such as type 2 diabetes, heart disease, bowel cancer, and it can also help prevent and manage constipation.
  • Provide a balanced nutrient intake –The amount of various nutrients in food is naturally balanced. Some supplements may contain high doses of a few nutrients and if not taken as directed, can upset the balance in the body and may even be harmful e.g. excessive vitamin A intake during pregnancy may cause birth defects.
  • Protective substances –Whole foods contain additional substances important for good health. For example, fruits and vegetables, contain naturally occurring substances called phytochemicals and antioxidants, which may help protect against free-radical damage and oxidative stress and reduce your risk against the ageing process, cell and tissue damage, inflammation, cancer, heart disease, diabetes and high blood pressure.

In addition to the above, there are certain population groups who may require daily supplementation in addition to a healthy diet. This may be because their nutrient requirements are increased or it may be challenging for them to obtain their recommended dietary intake of nutrients, from food alone. People who may benefit from vitamin and mineral supplementation include:

  • Pregnant women and women planning pregnancy
  • Women who are breastfeeding
  • The elderly (especially those living in assisted living or nursing homes)
  • Fussy eaters or people who don’t eat well or have a low calorie intake.
  • Some vegans or vegetarians who eat a limited variety of foods.
  • People who exclude certain food groups.
  • Elite athletes – including endurance, anaerobic, contact and power sports.
  • Women with heavy or excessive bleeding during menstruation.
  • Individuals who have a medical condition that affects how your body absorbs or uses nutrients, such as coeliac disease, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), chronic diarrhoea, food allergies and intolerance, or a disease of the liver, gallbladder or pancreas.
  • Individuals recovering from any surgery or have had surgery on their digestive tract and are not able to digest and absorb nutrients properly.
  • Alcoholics or heavy drinkers.