Nowadays many people have concerns, often unwarranted, about the use of food supplements.
In general, food supplements have been proen safe by repititive testing all over the world although it is generally acknowledged that it is difficult to set a 'recommended daily allowance', and for all nutritionists to agree on a recommended daily intake of any specific nutrient which is considered to be 'safe'
Of all the nutrients, there are only a very few that really need some restriction knowledge. These include the fat-soluble vitamins (A and D) which dissolve in fat and can be stored in the body, as opposed to water-soluble vitamins (e.g. the B group and Vitamin C) which dissolve in water and cannot be stored by the body. Thus excessive intakes of these vitamins are excreted harmlessly from the body.
This should not be taken in high doses, especially during the first trimester of pregnancy as it has anti-angiogenic properties which might lead to birth defects. On the other hand, a deficiency of Vitamin A during pregnancy might, in some circumstances, lead to birth defects and other problems.
Excessive intakes of Vitamin D (10.000 IU daily) can cause hyper-calcemia of soft tissues leading to arteriosclerosis. Vitamin D is toxic if taken in excess. However, we need an adequate supply for the maintenance of healthy bones. Some research studies have concluded that Vitamin D can help in the prevention of several forms of cancer.
It should be obvious that moderation is a good pracxtice in all things in life, including supplementation. Occasional use of high dosages have not been shown to be harmful and may have an almost miraculous benefit for some people under the proper guidance of a nutritionist who can be on the look-out for any untoward effect.
Vitamins and minerals are classed as micro-nutrients because we only need a small amount of them in our daily diet, as opposed to macro-nutrients such as protein and carbohydrate. Vitamins and minderals are measured in units known as micrograms and milligrams.
Fish, red meat, beans and pulses, carrots and broccoli are good sources of the mineral potassium.
As the interest in self-responsibility for personal health expands, nutrition becomes an obvious avenue to explore for people who care about their health. Science and research support nutritional concepts and the role of nutrition in preventing disease and maintaining good health. The major trend is to learn about nutrition for personal use and evaluate which supplement is best for the individual's needs. More doctors and scientists are recognising the important role of a nutritionally balanced, healthy diet in promoting and maintaining good health. The probability is that in the near future, diet and food supplementation will be a much larger part of "medicine" than they are today.