Topic of the Month

Micronutrient insufficiency: Risk groups

September 1, 2010

The conclusions drawn from numerous national nutrition surveys are that there is no prevalence of vitamin deficiencies ("as a statistical mean") in industrialized countries. As long as we eat a balanced diet including the foods recommended by the nutrition societies (e.g. five portions of fruit and vegetables a day), our vitamin requirements will be met. However, the nutrition experts admit that their investigations into vitamin intake in the general population revealed wide variations and that not everybody actually achieves the targeted reference values. Risk groups with comparatively poor dietary habits and inadequate micronutrient intake were identified in every age group.


Micronutrient insufficiency can range from severe “deficiency,” usually accompanied by obvious clinical symptoms, to a slight “insufficiency,” whose harmful consequences are not always immediately evident. Nevertheless, in the long term insufficiency, i.e. not consuming the recommended dietary amounts, can favor the development of chronic diseases such as cardiovascular diseases or cancer. As yet there is no consensus as to what constitutes an “ideal” intake of micronutrients and at which point the supply should be considered “suboptimal.” Furthermore, the actual amounts of nutrients required vary from one person to another, depending on age, sex, health status, lifestyle and genetic factors.



In the first four months of life babies are fed exclusively on breast milk or industrially produced infant formula milk. The composition of these diets mostly meets the nutrient requirements of a healthy infant. However, there are problems in this phase with vitamin D and vitamin K, which are not present in sufficient quantities in either of the diets.

For this reason supplementary vitamin D for rickets prevention is given as a matter of principle in the first year of life. A neglect of vitamin D prophylaxis, vegan diets with insufficient milk and milk products or a lack of exposure to the sun are currently causing rickets to reappear. In order to avoid bleeding in newborns caused by vitamin K deficiency, giving vitamin K on the 1st and 5th days of life and in the 4th to 6th weeks is recommended. From the fourth month, breast milk alone does not provide enough iron and vitamin C to cover the infant's requirements, so from this age solids are introduced gradually.


  1. Casey C. F. et al. Vitamin D supplementation in infants, children, and adolescents. Am Fam Physician. 2010 ; 81(6):745–8.
  2. Van Winckel M. et al. Vitamin K, an update for the paediatrician. Eur J Pediatr. 2009; 168(2):127–34.

Children and young people

Insufficient micronutrient consumption is particularly problematic for children and young people, since deficits can negatively influence the progress of their physical and mental performance. Children are especially at risk of insufficiency if they eat little or no fruit and vegetables, consume hardly any meat, milk or milk products, or generally eat very little. National food consumption studies have shown that one-year-old children, toddlers and schoolchildren consume only around half the recommended amount of vegetables, for example. Chronic illnesses or repeated bouts of acute infectious diseases one after the other with associated loss of weight also represent a threat.

Young people have a particularly high nutrient requirement when they experience a growth spurt. Many also have problems arising from the ideal body images in society: the intake of nutrients can become insufficient if energy reduced diets are followed over long periods because of real or imagined weight problems. For children and young people the risk that their intake of the B vitamins (especially B9), vitamins C and D and also calcium, magnesium and iron is insufficient is particularly high.


  1. Unuvar T, Buyukgebiz A. Nutritional rickets and vitamin D deficiency in infants, children and adolescents. Pediatr Endocrinol Rev. 2010; 7(3):283–91.
  2. Maggini S. et al. Essential role of vitamin C and zinc in child immunity and health. J Int Med Res. 2010; 38(2):386–414.


Among adults, too, risk groups with comparatively poor nutrient intake can be identified. These include people whose food intake is low due to frequent attempts to lose weight. If the average energy intake is around 1,000 to 1,500 kcal per day, an adequate supply of all micronutrients is almost impossible even in adults.

Regular smoking increases the need for antioxidant micronutrients such as vitamin C and carotenoids. At the same time, smokers generally eat less fruit and vegetables and drink less vitamin-rich fruit juices. However, this connection should not lead to the conclusion that increasing the intake of vitamins can compensate for the damage done by smoking. The only effective prevention is to stop smoking.

Regular substantial consumption of alcohol reduces the absorption of B vitamins and leads to increased elimination of vitamins via the kidneys. Gradually, the supply of B vitamins in the body diminishes. The supply of vitamin D (and calcium) is also affected, so that a higher incidence of fractures can be observed among alcoholics. If the liver is badly damaged, impaired vitamin K absorption can lead to blood coagulation disorders.

People living alone, particularly men, who usually avoid fresh fruit and vegetables, are regularly found to have low levels of vitamin C, vitamin B9 and carotenoids. People who seldom eat a warm meal suffer in particular from insufficient intake of B vitamins, vitamin C and vitamin E.


  1. Palaniappan U. et al. Fruit and vegetable consumption is lower and saturated fat intake is higher among Canadians reporting smoking. J Nutr. 2001; 131:1952–1958.
  2. Heseker H. et al. Vitaminversorgung Erwachsener in der Bundesrepublik Deutschland. [The Vitamin Intake of Adults in the Federal Republic of Germany] In: Kübler W. et al. Vol. IV of the VERA series. Fachverlag Dr. Fleck, Niederkleen. 1992.

Pregnant and breastfeeding women

During pregnancy and breastfeeding vitamin requirements are higher in general. Particularly during the second half of the pregnancy, substantial amounts of nutrients are transferred from the mother to the fetus. The main problems relate to intake of vitamin B9 (folate) vitamin A, vitamin D, calcium, iron and iodine.

Clinical studies show that the risk of developing neural tube defects and other complications of pregnancy can be significantly reduced by supplementing vitamin B9 (folic acid). Supplements should be taken at least four weeks before conception and maintained throughout the first trimester of pregnancy. For multiple births or frequent pregnancies total depletion of vitamin reserves can only be avoided by targeted vitamin substitution.

Vitamin A plays an important role in the healthy development of the fetus and newborn during pregnancy and breastfeeding. It is crucially involved in the growth and differentiation of a number of cells and tissues like the lungs. Although national nutrition societies recommend a significantly increased intake, they also advise avoiding consumption of vitamin A rich liver and foods containing liver. Therefore a sufficient intake of beta-carotene, as an essential and safe source of vitamin A, is very important.

Large-scale national studies have established vitamin D deficiency in up to 70% of pregnant women. A sufficient intake of vitamin D and calcium is not only important for bone health in mother and child, but can also reduce the risk of complications during birth, especially premature birth and infections.

A lack of iron is almost inevitable in pregnant women. Since the volume of blood increases by 25 to 40 percent during pregnancy and the fetus is also producing red corpuscles, iron requirements are raised. In order to prevent anemia, supplementation with iron is recommended. Iron-deficiency anemia in pregnant women increases the risk of premature birth, low birth weight and anemia of the newborn.

An adequate supply of iodine is especially important during pregnancy and breastfeeding. Hypothyroidism due to iodine deficiency not only threatens the health of the mother-to-be (e.g. goiter), but represents a risk to the physical and mental development of the child.


  1. Allen L. H. Multiple micronutrients in pregnancy and lactation: an overview. Am J Clin Nutr. 2005; 81(5):1206–1212.
  2. Ginde A. A. et al. Vitamin D insufficiency in pregnant and nonpregnant women of childbearing age in the United States. American Journal of Obstetrics and Gynecology. 2010; 202(5):436.e1–436.e8.
  3. Strobel M. et al. The importance of beta-carotene as a source of vitamin A with special regard to pregnant and breastfeeding women. Eur J Nutr. 2007; 46(1):1–20.


As they age, elderly people are found to consume less food and nutrients overall due to reduced energy needs, loss of appetite and difficulties chewing and swallowing. Disorders of the gastrointestinal tract, absorption problems and medication are further factors that can negatively affect the supply of nutrients.

Since with age the ability to synthesize vitamin D in the skin on exposure to UV radiation decreases and many elderly people are at least partially confined to the home, an adequate intake of vitamin D deserves special attention in the case of the elderly. A sufficient intake of calcium, vitamin D and possibly vitamin K can delay the occurrence of osteoporosis and slow its progress. In post-menopausal women, in particular, osteoporosis represents one of the most serious health problems. Even in the very old, increasing intake of calcium and vitamin D can have positive effects.

Around a third of the over-70s no longer produces sufficient gastric acid. This hinders the necessary breakdown of the food through the digestive process, i.e. the release of nutrients is impaired. This affects vitamin B12 in particular. For this reason, vitamin B12 deficiency is the vitamin deficiency most frequently requiring treatment in the industrialized world. Often it means a stay in hospital. Because of a combined deficiency of vitamins B9 (folic acid), B12 and B6, elderly people often have raised blood levels of homocysteine, which is associated with an increased risk of arteriosclerosis.


  1. Bischoff-Ferrari H. A. et al. Benefit-risk assessment of vitamin D supplementation. Osteoporos Int. 2010; 21(7):1121–32.
  2. Stover P. J. Vitamin B12 and older adults. Curr Opin Clin Nutr Metab Care. 2010; 13(1):24–7.


A vegan diet is characterized by the avoidance of all food of animal origin. Studies have shown that in vegans, the intake of vitamin B12, in particular, was below the officially recommended dietary amounts. Especially during pregnancy the risk of vitamin B12 deficiency can rise substantially, making medical supervision advisable. Further, vegans, especially vegan infants and toddlers, are at great risk of vitamin D deficiency, which can have serious consequences for bone mineralization.

To ensure adequate synthesis of the omega-3 fatty acids, vegans are advised to increase their consumption of rapeseed oil. Moreover, since docosahexaenoic acid is very important for the development of the newborn brain and retina, deficiency during the embryonic stage and later in breast milk must be prevented by a suitable diet. Since plant products are lower in calcium than milk or milk products, an increased risk of osteoporosis cannot be excluded for vegans. Theoretically there is also a risk of inadequate intakes of iron, zinc and selenium, although precise data are not available. Vegans therefore have to take special care when composing their diet. In individual cases, consuming supplements and fortified foods can be a practical solution.


  1. Craig W. J. Health effects of vegan diets. Am J Clin Nutr. 2009; 89(5):1627–1633.
  2. Koebnick C. et al. Long-term ovo-lacto vegetarian diet impairs vitamin B-12 status in pregnant women. J Nutr. 2004; 134(12):3319–26.

The chronically ill

Chronic diseases are often accompanied by multiple nutrient deficiencies. Some health problems reduce food intake (e.g. lack of appetite or eating, chewing and swallowing difficulties), while other illnesses can limit the absorption of micronutrients (e.g. pancreatic insufficiency, intestinal infections or inflammation). There are also diseases that are associated with significant losses of micronutrients (e.g. chronic diarrhea, chronic renal insufficiency) or increased utilization (e.g. fever, large wounds, infections). Taking medication can also have a negative effect on nutrient supply.

Feeding patients whose nutrient requirements cannot be met by normal foods demands extra care. The composition of the diet and its supplementation with appropriate preparations should be carried out under medical supervision and with the aid of nutrition experts.


  1. Pittas A. G. et al. Role of vitamin D in adults requiring nutrition support. J Parenter Enteral Nutr. 2010; 34(1):70–8.
  2. Biesalski H.-K. Vitamin E requirements in parenteral nutrition. Gastroenterology. 2009; 137(5):92–104.