OBESITY Figure 3: Relative risk of type 2 diabetes (NIDDM) with increasing weight

about one third. Xenical can be prescribed by a GP but it must be taken in conjunction with a reduced fat diet and as part of an overall weight management programme which includes physical activity. Studies have shown that patients taking Xenical in con- junction with a reduced fat diet lost around 70% more weight compared with those following a mildly reduced fat diet and placebo. GPs may prescribe Xenical once the patient has already started a weight management programme which has produced a weight loss of at least 2.5kg over four weeks. There is also a com- prehensive patient pack containing dietary and activity plans and information and a freephone helpline, staffed by nurses, which provides support for healthcare professionals as well as patients. There is no current evidence supporting the use of bulk-forming agents in long-term weight reduction.

Len Almond is director of The Exercise and Health Research Development Group at Loughborough University. Ilana Newberry is research co-ordinator for the group who are work- ing on a three year research programme on the management of obesity in primary health care.

Key facts and messages ● After smoking, obesity is potentially the most preventable

Figure 4: Energy expenditure patterns resulting from different lifestyle habits

extra body weight (6). For the overweight and obese person these recommendations are sufficient to improve overall health status and increase energy expenditure in those who were previously sedentary.

It may be helpful for healthcare professionals to compile a simple activity programme with realistic goals and targets and to encour- age patients to record their efforts and revise their goals as nec- essary - this will help them evaluate their efforts and see positive progression. Some people will need more support than others. They should also be encouraged to consider what activity alterna- tives they can do for a rainy day or dark night - there should be no opportunities for excuses.

Safe practice The risks of physical activity for obese people are small provided that it is introduced gradually and other complications such as osteoarthritis and ischaemic heart disease are taken into account. They should avoid high intensity and high impact activities. Asthmatics should be able to cope with the intensities suggested provided they take their necessary medication prior to the activi- ty. Arthritics may find weight bearing exercises difficult, but non- weight bearing activities such as cycling and swimming should help their condition as well as controlling their weight.

Medication If weight loss through a combination of a healthy diet and phys- ical activity is not achieved in the first three months, anti-obesi- ty drugs may be justified in adults with a BMI greater than 30. Just over a year ago the anti-obesity treatment Xenical was launched. The drug works by inhibiting the enzyme that breaks down fat, effectively reducing the absorption of dietary fat by

cause of ill health ● By 2010 it is predicted that 25% of the UK’s adults will be obese ● It’s better to be active and fat than inactive and thin ● Diets combined with exercise are nearly twice as effective for weight loss as diets alone ● Some obese people may have difficulty in achieving very low levels of exercise and so it is important to convey the message that any increase in physical activity levels, however small, will be beneficial in terms of health ● More frequent low intensity activity is more beneficial than a single intense burst for weight loss ● Walking has been shown to be the most important weight loss activity as it is weight bearing, aerobic and can be done easily by most people for a considerable length of time ● Advise patients to increase their daily routine activity eg. gardening and housework, walking upstairs ● Encourage activities that involve moving their own body weight and using large muscle groups

References 1. Prescott-Clarke P, Primesta P. Health Survey for England 1997. HMSO 1999 2. Obesity - preventing and managing the global epidemic. Geneva WHO 1998

3. Susan Jebb. The Weight of the Nation: Obesity in the UK. A report com- missioned by the Bread for Life Campaign 1999 4. Allied Dunbar National Fitness Survey. Health Education Authority and Sports Council 1992 5. Lee CD, Jackson AS, Blair SN. US weight guidelines: Is it also important to consider cardiorespiratory fitness? Int. J. of Obesity 1998;22(Suppl.2):S2-87 6. Fox K. Aetiology of Obesity XI: Physical inactivity in obesity. A report of the British Nutrition Foundation Task Force 1999-11-24 7. King AC, Tribble DL. The role of exercise in weight regulation in non- athletes. Sports Medicine 11:331-349 8. Adapted from Blaire SN, Kohl HW, Gordon NF. Physical activity and health: A lifestyle approach. Medicine, Exercise, Nutrition and Health 1992;1:54-57 9. Managing weight: A workbook for health professionals. Health Education Authority 1998

SportEX 15