eating herbsThere is a complex and dynamic interaction between the body (its structure, its processes and functioning) and foods and nutrients.


"The doctor of the future will give no medicine, but will interest his patients in the care of the human frame, in diet and in the cause and prevention of disease."


- Thomas Edison.


Eating (or not eating) particular foods and supplementing with nutritional supplements has an important influence on a person’s health and well-being. Nutritional medicine is the art and science of knowing which foods or supplements an individual person needs to promote optimal health. There is a mass of scientific evidence that there is a direct relationship between health or ill-health and diet.

The body has nutritional requirements for optimal functioning:


  • protein (amino acids)
  • fats (particularly essential fatty acids like omega 3)
  • carbohydrates


  • vitamins
  • minerals
  • antioxidants
  • phytonutrients


Individual requirements


Nutritional requirements may vary from person to person depending on factors like genetics, metabolic type, age, gender, stress, state of health and activity levels. A person’s ability to utilise and absorb nutrients may also vary depending on the efficiency of their digestive system. Also important is the body’s ability to neutralise and eliminate toxins and metabolic by-products effectively.




In an ideal world, humans would get all necessary nutrition from food. Unfortunately, modern farming methods, food production, processing, transportation and storage denude the food of vital nutrients. Many illnesses and symptoms can be as a result of nutritional deficiencies.


Causes of nutrient deficiencies in food
  • Produce is harvested before it is ripe and the vitamin content has fully matured.
    Soils are seriously depleted by over-farming and chemical fertilisers replace only a few minerals.
  • Fruits and vegetables are subjected to a wide range of toxic chemicals while they are growing (an apple can come into contact with a shocking 63 chemicals in the orchard alone).
  • Animals are fed antibiotics, hormones and feeds different from their natural diet (e.g. farmed salmon are fed grain which reduces their omega 3 fatty acids).
  • Refining processes strip food of fibre as well as vitamins and minerals.
  • Processed foods are, by their nature, nutritionally depleted by cooking and processing and are also loaded with sugar, salt, preservatives and other additives which tax the body and drain it of vital nutrients used to digest and detoxify them.
  • Supermarket chains store fresh foods in computer controlled environments, sometimes for months, the vitamin and mineral content continually degrading.
An example


Vitamin C is needed for at least 300 metabolic functions of the body. Most animals make their own but humans, primates and guinea pigs (all descended from a common evolutionary ancestor) cannot. Animals which make large amounts of vitamin C do not get heart disease (unless they are diabetic). Guinea pigs and humans do get heart disease. It is unlikely that many people are getting enough vitamin C in their food (even if they are eating a good diet), so there is a strong case for supplementing with vitamin C to prevent heart disease alone. Vitamins, herbs and supplements are powerful substances and it is prudent to be knowledgeable about their effects before taking them – or rely on the expertise of a professional.

It is helpful to understand the basic functions of nutrients in the body: