Who is susceptible to vitamin deficiency?
Targets for Vitamin Deficiency
Serious deficiency diseases like rickets or beriberi are almost non-existent in developed countries. However, there are certain defined groups in the community who are more at risk of vitamin deficiency than others. Some of these risk groups are victims of lifestyle and the modern uncertainties of a balanced diet. Other risks are self-inflicted (alcoholism) or the result of natural causes (pregnancy).
The elderly are probably the largest group of individuals at risk of deficiency in Australia. There are a number of reasons for this:
- If they live alone they may not bother to prepare adequate food for themselves. A widower, used to his wife's cooking, is especially vulnerable.
- Because of reduced physical activity they need less food and so their overall kilojoule intake may not be sufficient to provide adequate vitamins.
- Their sense of taste may diminish - and with it a lack of interest in food.
- The capacity of the intestines to absorb vitamins can decline in old age.
A good balanced diet is particularly important for the elderly who sometimes increase their deficiency risk by replacing proper meals with refined carbohydrate snacks (biscuits) . People with small appetites need vitamin rich foods otherwise their diet will be inadequate.
Pregnant and Breast Feeding Women
As you will have noticed from the Recommended Daily Intake sections in the chapters on each individual vitamin, the requirements for a pregnant or breast feeding mother are greater than for the rest of the adult population.
In most cases, however, a good balanced diet should supply most of the necessary vitamin intake. The possible exception here is folate. Folate deficiency in mothers has been known to cause abnormalities in babies. All pregnant mothers should eat a diet high in folate and take a supplement if this is suggested by their doctor.
There are really three types of vegetarians:
- Vegans, who eat only food from plant sources.
- Lacto-vegans, who add dairy products to their plant diet.
- Lacto-ovo-vegetarians, who add eggs and dairy products to their basic plant diet.
The first two categories of vegetarians have almost no deficiency risk providing they plan their diet correctly. However, strict vegans can be at risk since B12 is only found in animal foods and a small number of specially enriched foods of which only a fortified yeast product is readily available in Australia.
In practice, very few vegans do have a B12 deficiency. The precise reason for this is unknown but there are theories that B12 is produced in the body by bacteria in the intestine and that it is present in certain plants.
B12 is also stored in the body's liver for about five years, so only longstanding vegans run any degree of risk.
People On the Pill or Other Prescribed Drugs
When the oral contraceptive pill was first marketed in the early 1960s it was established by researchers that the hormones in the Pill could interfere with the availability of pyridoxine (B6) and cause depression.
The hormone (estrogen) content of the pill has been lowered since those days, almost eliminating the possibility of B6 deficiency.
Certain other well known drugs definitely impair the body's ability to absorb certain vitamins. If your doctor prescribes one of these drugs, he should tell you about it and advise a vitamin supplement.
New Born Babies
Nearly all prematurely born babies have a low level of vitamins E and K since these two vitamins have difficulty in passing from the mother's placenta (the baby's food source) to the foetus. Consequently they are often at risk of a particular type of anemia or a bleeding disease.
Although breast milk is rich in vitamin E, supplements are often suggested by the doctor.
Because the premature baby has a small vitamin store to begin with, as well as only a moderate rate of vitamin absorption, other vitamin supplements are often given.
Most doctors consider that full term babies, either breast fed or on a good formula, have no need for extra vitamins. However, a healthy dose of vitamin K (direct from the sun) is always advisable - but mothers are warned not to leave their babies exposed to the sun's rays for more than about ten to fifteen minutes at a time on an average day.
Low Income Earners
Food buying surveys have shown that the smaller the food budget, the lower the standard of diet generally is.
There is a certain unfortunate logic in that but many people also make poor use of the money available. For example, in the survey quite a high proportion of the budget dollar was spent on expensive protein such as meat rather than the less expensive protein sources such as legumes. Because of this unbalanced spending on meat there often wasn't sufficient money left over for an adequate supply of nutrient rich foods such as fruit and vegetables.
Studies have shown that young unemployed people tend to spend too high a proportion of their food money on take-away food which is neither cheap (in comparison to what it would cost to prepare at home) or particularly nutritious unless the food has been selected in a balanced manner.
If you are trying to lose weight by following a strict low kilojoule diet (say 4,500 kilojoules per day) it is almost impossible to gain all the vitamins you need from this low amount of kilojoules. Remember, most of the B complex group cannot be stored in the body.
To compound the problem, most dieters have lapses ("I'd kill for a cream bun!") and then tend to eat a large quantity of food high in kilojoules but low in vitamins.
No serious diet should be attempted without medical supervision and your doctor will advise vitamin supplements if it is considered necessary in your particular case.
Most alcoholics have a very poor eating pattern which in itself makes them a target for vitamin deficiency due to bad nutrition. In addition to this, alcohol seriously interferes with the body's absorption of vitamins.
Wernicke's encephalopathy, a very serious mental disorder caused by a B1 deficient diet, is considered the most serious vitamin deficiency disease in Australia. The majority of sufferers from this illness are alcoholics.
As a group alcoholics, or very heavy drinkers, tend to be deficient in the B complex group, folate and vitamin C.
It has been widely reported that smokers are at risk of a vitamin C deficiency. It would be more accurate just to say: smokers are at risk - full stop - regardless of any vitamin deficiency.
Although most smokers have slightly lower blood levels of vitamin C than non smokers, tests have shown that their levels usually remain well within the normal range.