gms | German Medical Science

GMS German Medical Science — an Interdisciplinary Journal

Association of the Scientific Medical Societies in Germany (AWMF)

ISSN 1612-3174

Effects of weight-reduction on obesity-associated diseases

Auswirkungen einer Gewichtsreduktion auf Adipositas-assoziierte Krankheiten

Short Report

Search Medline for

German Medical Science 2003;1:Doc04

The electronic version of this article is the complete one and can be found online at: http://www.egms.de/en/journals/gms/2003-1/000004.shtml

Received: May 14, 2003
Published: July 1, 2003

© 2003 Liebermeister.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Abstract

Even moderate, but persistent weight-loss ameliorates most of the related diseases in obesity. Besides the consequences of the metabolic syndrome, this includes less well-known obesity-associated changes, such as impaired fertility, menstrual disorders, psychic changes, total leucocyte-count as a parameter of immunity and the impaired pulmonary function in asthma and sleep-apnoea.

Life-expectancy is prolonged by diminution of visceral fat depots, whilst weight-loss by shrinking of fat-free body-mass seems to have a contrary effect.

Zusammenfassung

Auch eine mäßige, aber dauerhafte Gewichtsverringerung bessert die meisten Begleitkrankheiten der Adipositas. Dazu gehören - neben dem Metabolischen Syndrom - auch weniger bekannte Folgeerscheinungen der Adipositas, wie Fertilitätsstörungen, Menstruations-Anomalien, psychische Veränderungen, die Gesamt-Leukozyten-Konzentration als Parameter für die Immunitäts-Lage und die gestörte Lungenfunktion bei Asthma und Schlaf-Apnöe.

Die Lebenserwartung erhöht sich nach Verringerung der intraabdominalen Fett-Depots, während ein Gewichtsverlust infolge Abbaus der fettfreien Körpermasse den gegenteiligen Effekt auszulösen scheint.


Text

A meta-analysis of 23 studies on 599 volunteers [1] has shown that - independently of the procedure chosen - visceral fat is diminished more effectively than total fat. Thus the potentially dangerous visceral fat responds especially well to weight reduction.

We therefore may expect that weight reduction has a favorable effect on obesity-associated diseases.

It is well known that more than 80 % of non-insulin-dependent diabetics are overweight. S.D. Müller from Aachen has put it this way: "Type-2-diabetics don't have diabetes, but a belly." He is getting nearer to the truth, as the starvation-periods during and after both world-wars lowered diabetes-mortality much more than the introduction of insulin or of oral anti-diabetic medication. Moreover, weight reduction leads - as has been well known for many years [2] - to a clear-cut reduction of elevated serum-levels of glucose, triglycerides and insulin.

This metabolic improvement and the normalization of insulin-incretion with a pronounced early phase and moderate long-term incretion persist only however if there is no substantial regain in weight [3].

Many diabetics can - depending on the degree of their weight-loss - reduce or abandon their medication: insulin or oral anti-diabetics and limit themselves to purely dietetic measures [4].

Pronounced weight-loss after surgical treatment of obesity III has dramatic effects as shown by the 2 years follow-up of the Scandinavian Obesity Study (SOS) [Tab. 1] [5].

The diabetes incidence in the surgically operated group is therefore 16 times lower than in the conventionally treated group. Even ten years after the surgical intervention, diabetes-risk is still 3,4 times lower [6].

A moderate weight-loss not only improves the diabetic metabolism, but also ameliorates other risk-factors inherent to the metabolic syndrome [7]:

A meta-analysis of 14 studies has shown that a weight reduction by 10 % - (= ca. 10 kg) - leads to a lowering of the accompanying hypertension. A weight loss of 10 kg diminishes systolic blood-pressure by approximately 15 mmHg, the diastolic pressure by about 10 mmHg [8].

Another meta-analysis of 16 controlled studies by the Cochrane Collaboration demonstrated in every one of them that weight-reduction was significantly more effective in this respect than a low-salt-diet or even antihypertensive medication [9].

Weight-loss also induces a lowering of hyperlipoproteinemia with an increase of HDL-levels [10].

In addition, the muscular mass of the left ventricle, another recognized risk-factor, decreases by successful weight reduction [11].

A drastic weight-lowering by gastric banding leads to an improvement of pulmonary function [12]. In addition, a strict caloric restraint with a 14,5 % reduction in starting-weight induced in 19 obese patients with asthma led to significant improvements in pulmonary function, extent of medication, subjective well-being and frequency of attacks even after one year [13].

In 315 obese patients with BMI above 35, gastric banding led to a weight reduction of 30 kg on average and lowered the percentage of "snorers" from 82 to 14 %, the frequency of OSA (obstructive sleep-apnoea-syndrom) fell from 33 to 2(!) % and instead of 39 % only 2 % claimed afterwards that they did not sleep well [14].

During the SOS-study mentioned above, it could be demonstrated that a weight-loss of 22 kg on average by surgical intervention diminished the increase of intima-media-diameter in the carotid bulbus by two/thirds to a degree which can be observed in a control population [15] of slimmer individuals.

Whilst urate-levels during fasting increase distinctly - especially if patients do not drink enough - due to a competition in excretion between uric acid and ketone-bodies produced in large amounts during fasting, urate concentration falls considerably after long-term weight-reduction [16].

Even the increased total leucocyte-count as an indication of an impaired immunity-situation in obesity responds to a weight-lowering [17].

It is a well known fact that successful weight-reduction can normalize menstruation-disorders and impaired fertility in obese women [18]. In our Optifast®-center, we had to stop several weight-reduction-measures because of a pregnancy which developed unexpectedly after a long period of sterility [19].

Parallel to weight-lowering, we could also largely normalize the parameters of neuroticism and extraversion which show pathologic deviations in obesity [20].

It took a long time, until the hoped for improvement in life-expectancy by weight-reduction could really be proven. Numerous studies led to diverging results, mostly because there was no differentiation between a therapeutic weight-reduction and weight-loss by severe diseases. Retrospective analysis has demonstrated that fat-loss itself improves life-expectancy, whilst pure weight loss may lead to its decrease, as has been shown in two especially well controlled community-studies: Tecumseh Community Health Study: 321 deaths in 1,890 participants after 16 years observation [21] and the Framingham Heart Study: 507 deaths in 2,731 participants after 8 years [22]. This probably explains the divergent findings and hypotheses about the improvement in life-duration after weight loss.

Apart from first hints in the Build-Study 1979 [23], we have now 3 studies which lend support to the hypothesis that weight reduction does not only improve risk-factors, but also prolongs life:

- In white US-women, observed during 12 years by the American Cancer Society, voluntary weight losses between 0,5 and 9 kg lowered total mortality by 20 % [24]. Carcinoma-mortality was reduced by 37 %, diabetes-mortality by 44 % and cardio-vascular mortality by 35 %. This effect was especially impressive in women with an unfavourable pre-investigation situation.

- In India, Singh et al. [25] reported a diminished mortality after myocardial infarction in patients who liberally consumed fruits and vegetables and this improvement was especially pronounced after a weight-reduction by 10 %.

- After vertical gastroplasty, the 10-years-mortality reached 10 % in the non-operated control-group and only 3,7 % in the extremely obese treated by surgical intervention [26].

Reduction of the visceral fat depots seems to be the decisive factor for the improvement in life-expectancy, whilst pure weight-loss seems to have a rather life-shortening-effect [21].

Finally, we should consider that our patients are (much) more impressed and motivated by other facts [27]: "I can again go dancing at last and buy attractive clothing", "I now can tie my shoes myself", or "my jogging partner Bruno with slight overweight is glad because he beats me again after losing 6 kg as he used to before".


References

1.
Smith SR, Zachwieja JJ. Visceral adipose tissue: a critical review of intervention strategies. Int J Obes Relat Metab Disord 1999;23:329-35.
2.
Liebermeister H, Daweke H, Gries FA, Schilling WH, Grüneklee D, Probst G, Jahnke K. Einfluss der Gewichtsreduktion auf Metabolite des Kohlenhydrat- und Fett-Stoffwechsels und auf das Verhalten des Seruminsulins bei Adipositas. Diabetologia 1968;4:123-32.
3.
Hewing R, Liebermeister H, Daweke H, Gries FA, Grüneklee D. Weight regain after low-calorie diet: long-term pattern of blood sugar, serum lipids, ketone bodies, and serum insulin levels. Diabetologia 1973;9:197-202.
4.
Laube H, Mehnert H. Ernährungstherapie. In: Mehnert H, Standl E, Usadel KH. Diabetologie in Klinik und Praxis. 4. Aufl. Stuttgart, New York: Thieme; 1999:120-46.
5.
Sjöström L. Intervention studies in obesity. In: International Monitor on Eating Patterns and Weight Control. Medicom Europe;1995.
6.
Torgerson JS. Die "Swedish Obese Subjects"-(SOS)-Studie: was bringt Abnehmen wirklich? MMW Fortschr Med 2002;144(40):24-26.
7.
Goldstein DJ. Beneficial health effects of modest weight loss. Int J Obes Relat Metab Disord 1992;16:397-414.
8.
Tuck ML, Sowers J, Dornfeld L, Kledzik G, Maxwell M. The effect of weight reduction on blood pressure, plasma renin activity, and plasma aldosterone levels in obese patients. N Engl J Med 1981;304:930-3.
9.
Mulrow CD, et al. Dieting to reduce body weight for controlling hypertension in adults. Cochrane Library 2001:1-40.
10.
Schieffer B, Moore D, Funke E, Hogan S, Alphin F, Hamilton M, Heyden S. Reduction of atherogenic risk factors by short-term weight reduction: evidence of the efficacy of National Cholesterol Education Program guidelines for the obese. Klin Wochenschr 1991;69:163-7.
11.
MacMahon SW, Wilcken DE, Macdonald GJ. The effect of weight reduction on left ventricular mass: a randomized controlled trial in young, overweight hypertensive patients. N Engl J Med 1986;314:334-9.
12.
Refsum HE, Holter PH, Lovig T, Haffner JF, Stadaas JO. Pulmonary function and energy expenditure after marked weight loss in obese women: observations before and one year after gastric banding. Int J Obes 1990;14:175-183.
13.
Stenius-Aarniala B, Poussa T, Kvarnström J, Grönlund EL, Ylikahri M, Mustajoki P. Immediate and long term effects of weight reduction in obese people with asthma: randomised controlled study. BMJ 2000;320:827-32.
14.
Dixon JB, Schachter LM, O'Brien PE. Sleep disturbance and obesity: changes following surgically induced weight-loss. Arch Intern Med 2001;161:102-6.
15.
Karason K, Wikstrand J, Sjöström L, Wendelhag I. Weight loss and progression of early atherosclerosis in the carotid artery: a four-year controlled study of obese subjects. Int J Obes Relat Metab Disord 1999;23:948-56.
16.
Facchini F, Chen YD, Hollenbeck CB, Reaven GM. Relationship between resistance to insulin-mediated glucose uptake, urinary uric acid clearance, and plasma uric acid concentration. JAMA 1991:266;3008-11.
17.
Field CJ, Gougeon R, Marliss EB. Changes in circulating leukocytes and mitogen responses during very-low-energy all-protein reducing diets. Am J Clin Nutr 1991:54:123-9.
18.
Given WP, Gause RW, Douglas RG. Rational therapy for secondary amennorrhea. N Engl J Med 1950:243:357-62.
19.
Lenthe-Schäfer, K. Medikamenteneinsparung durch Gewichtsreduktion [Dissertation]. Saarbrücken: Univ.; 1999.
20.
Aretz HH, Liebermeister H, Schultz H, Probst G. Psychische Veränderungen bei adipösen Patienten während einer ambulanten Reduktionskur. Dtsch Med Wochenschr 1971;96:778-84.
21.
Allison DB, Zannolli R, Faith MS, Heo M, Pietrobello A, VanItallie TB, Pi-Sunyer FX, Heymsfield SB. Weight loss increases and fat loss decreases all-cause mortality rate: results from two independent cohort studies. Int J Obes Relat Metab Disord 1999;23:603-11.
22.
Hubert HB, Feinleib M, McNamara PM, Castelli WP. Obesity as an independent risk factor for cardiovascular disease: a 26 year follow-up of participants in the Framingham Heart Study. Circulation 1983;67:968-77.
23.
Society of Actuaries and Association of Life Insurance Medical Directors of America. Build Study, 1979. Philadelphia, Chicago; 1980.
24.
Williamson DF, Pamuk E, Thun M, Flanders D,Byers T, Heath C. Prospective study of intentional weight loss and mortality in never-smoking overweight US white women aged 40-64 years. Am J Epidemiol 1995;141:1128-41.
25.
Singh RB, Niaz MA, Ghosh S, Rastogi SS. Effect on mortality and reinfarction of adding fruits and vegetables to a prudent diet in the Indian experiment of infarct survival (IEIS). J Am Coll Nutr 1993;12:255-61.
26.
Husemann B, Reiners V. Erste Ergebnisse nach vertikaler Gastroplastik zur Behandlung der extremen Adipositas. Zentralbl Chir 1996;121:370-5
27.
Liebermeister H. Adipositas: Ursachen, Diagnostik, moderne Therapieoptionen. Köln: Deutscher Ärzteverlag; 2002:198-209.