UNDERWEIGHT

In today's world where slim is the ideal, we tend to forget about the possibility of being too thin. But underweight is a very real problem indeed, and one which frequently requires medical investigation and treatment.

Mothers are often concerned that their children are underweight - perhaps because in times gone by, thin children were more at risk from infectious diseases than fat children with 'reserves'. It was a sign of love and good mothering to have a large 'bonny baby'.

Nowadays, we know that being overweight is undesirable for a number of reasons, but parents will worry that a slim child is underweight. In adults the problem of being underweight is more clear-cut. Most adults know what their weight usually is; what it should be; and whether they have lost weight recently.

NATURALLY THIN OR UNDERWEIGHT ?

Anxious parents can weigh their children at regular intervals, and take the records to their doctor. The doctor has charts or graphs, called percentile charts, which show the average normal curve for all ages for both weight and height.

There are similar weight charts for adults, but likewise, they are only an approximate guide to a person's natural weight. Both the amount of energy we take in (in the form of calories) and the amount of energy we burn up are influenced by several factors, and each person will vary in his or her response to each stimulus. To say what is an 'ideal' amount of fat is very difficult. Olympic athletes, for example, are very fit, but their correct weight for a particular height will vary with the event at which they excel. Sprinters are fairly heavily built, whereas a marathon champion may appear very underweight.

As long as you are healthy, being thin may well be a good thing since statistics show that lean people live longer than fat people, and are less prone to certain conditions such as heart disease and high blood pressure.

However, people are underweight for a variety of reasons, many of which need investigation and treatment. The common reason world-wide is, of course, malnutrition.

THE UNDERWEIGHT BABY

Some babies are born small, even after a full-term pregnancy simply because their parents are small. They are naturally slight and are just as capable as a heavier baby in adapting to an independent existence. No special management is necessary even though such a baby may weigh less than 2.5 kg (51'2 lb) if he or she is fully matured.

However, not every baby who arrives on time but weighs less than 2.5 kg (51 -, 1b) is following a family pattern. Some-times a baby is small because he or she has been starved in the womb. The reasons for this starvation are not always obvious. Certainly, women who smoke are more likely to have 'small-for-dates’ babies. Malnourished mothers will also produce small babies, and it also appears that mothers who do not attend antenatal clinics and who have a generally poor understanding of health matters are big likely to have underweight babies. Both premature and underweight-for- dates babies have to be kept in hospital. They are fed and monitored carefully until their maturity and weights are up to a certain level. Usually this is about 2.3 kg (5 lb), but this is only a guide and may vary depending on the baby’s progress and home circumstances.

FAILURE TO THRIVE

When a baby does not thrive and gain weight at a satisfactory rate; doctors call this ‘failure to thrive’. If this condition is persistent, then a reason must be found. Most of the time this will be obvious, but occasionally the baby will have to be admitted to hospital for special investigations. The baby may not be having sufficient milk, for example. Breast milk is of course much the best food for a baby, and supplies increase the more the baby sucks. However, some mothers who choose to bottle feed their babies misread the instructions on the labels, or do not increase the amount of milk as the baby grows, so that the baby is being underfed. He or she will be irritable and unhappy, and will not gain weight. The health visitor will always be of help with infant feeding problems.

Any infection, such as gastro-enteritis. or pneumonia, can result in underweight. The cause must be diagnosed and treated quickly. Cystic fibrosis of the pancreas is a condition where there is poor absorption from the intestines and also repeated chest infections in the infant or young child. This can be diagnosed by examining a sample of sweat from the child’s skin. Congenital abnormalities, such as heart defects, hydrocephalus and severe cleft palate all affect the infant’s ability to thrive.

NERVOUS CONDITIONS

Anxiety states and depressive illness are frequently the causes of underweight in adults, and occasionally in children. In depression the desire to eat often goes. It is too much trouble to think about food, or to prepare a meal for oneself. There may be other problems such as poor sleep, or features of anxiety such as panic attacks, agitation and palpitations. People may be unaware that they are depressed, if they cannot see any reason why they should be so. This is the so-called ‘endogenous’ type of depression. A doctor can often be helpful, both by providing a ‘sympathetic ear’. And also treatment with special drugs.

Many people experiences the reactive depression to a sad experience such as bereavement, or a particularly distressing personal problem. This can certainly reduce the appetite and people then lose weight. This type of depression passes in time, but meanwhile a doctor may be able to help these patients.

There is also a condition called anorexia nervosa which mainly affects young adults, in particular women. What begins as a desire to be thin develops into an obsession. Little or nothing may be eaten, while sufferers still regard themselves as overweight. Unless medical help is sought the anorexic may be at risk of starving him or herself to death.

HORMONE DISORDERS

An over-active thyroid gland, or thyro-toxicosis, causes an excess release of 'thyroid’’ hormone into the bloodstream. This speeds up many systems in the body, causing an increased mobilization of fat stores and liver energy stores. Extra glucose is released which is used up to produce extra energy in the form of heat. The result is someone who is warm, sweating and shaking, with a rapid heart rate. A great deal of heat energy is produced, and sufferers often feel very tired. Appetite is increased and weight is lost. The treatment of this condition is to reduce the production of the hormone with drugs, to remove part the thyroid gland surgically or to destroy it partly with radioactive iodine.

INFECTIONS AND DISEASE

Loss of weight for no apparent reason should always be reported to a doctor as it can sometimes be a symptom of disease of the blood, kidneys or lymph glands, and other conditions, such as cancer, which reduce the absorption of food. People often lose weight while an infection is present. Usually this is easily made up after recovery.

STIMULATING THE APPETITE

Frequently people who are underweight are so because they cannot be bothered to eat. This may be result of depression, being too busy, or simply because a person lives alone and mealtimes are not much of an occasion. There is no doubt that eating with others is an enjoyable social experience and can stimulate a desire for food- and this applies to children as well as adults. Mothers all too often regard children’s mealtimes as a time to get on with the housework, while the children have their food ‘dumped’ in front of them. Then they wonder why the children wont eat it.

Where elderly people live alone, having the opportunity to eat with others in luncheon clubs may be very helpful. A glass of sherry or some other alcoholic drink before a meal is also a very good appetite stimulate. People who want to put on weight should resist the temptation to fill up on sugary ‘junk foods, just because they are fattening. They are of no benefit to health and will only promote dental decay. Instead, slow down. Eat regular relaxed meals which include plenty of protein, carbohydrate and fiber (roughage).