Development of abdominal fat and incipient metabolic syndrome in young healthy men exposed to long-term stress.
OBJECTIVE
The sympathetic nervous system may be involved in the pathophysiology of insulin resistance and metabolic cardiovascular syndrome in young men. The aim was to study the effects of long-term stress on different features of the metabolic syndrome (MES) in formerly non-obese healthy young males during 5 months of defined conditions.


RESULTS
Sixteen healthy male sailors (mean age 36.5 (SD)+/-7 years) participating in a sailing race around the world were recruited for the study. Investigations were done before the start and at stop overs after finishing laps 1, 2 and 4 (1, 2(1/2) and 5 months, respectively). Anthropometric and blood pressure data as well as biochemical data associated with MES were substantiated. Food intake and exercise were chartered and largely controlled. A mean weight loss of 4.5+/-2 kg (P<0.005), comprising both fat and lean body mass, was recorded during the first lap. Subsequently after 5 months, a weight gain, mainly consisting of 1.2+/-1.1 kg body fat (P<0.05), took place, concomitantly with a protein mass drop of 0.6+/-1.1 kg (P<0.05). The body fat gain accumulated on the abdominal region. Elevated blood levels of HbA1c, insulin and the triglycerides/high-density lipoprotein ratio were also observed during the race. Likewise heart rate and systolic blood pressure increased slightly but to a statistically significant extent.


CONCLUSIONS
Non-obese healthy young men exposed to long-term stress developed abdominal obesity and signs of a metabolic syndrome in embryo, also emphasized by biochemical and blood pressure alterations. It is suggested that long-term and sustained stress activation might be an additional risk factor for the development of MES, even after control of dietary and exercise habits.
Branth
Stefan
S
Department of Medical Sciences, Section of Nutrition, University of Uppsala, University Hospital of Uppsala, SE-751 85 Uppsala, Sweden. stefan.branth@medsci.uu.se <stefan.branth@medsci.uu.se>
Ronquist
Gunnar
G
Stridsberg
Mats
M
Hambraeus
Leif
L
Kindgren
Erik
E
Olsson
Roger
R
Carlander
David
D
Arnetz
Bengt
B
D050153:Abdominal Fat / Q000378:metabolism*; D000328:Adult; D000886:Anthropometry; D001794:Blood Pressure; D001835:Body Weight; D002908:Chronic Disease; D002149:Energy Intake; D006442:Glycated Hemoglobin / Q000378:metabolism; D006339:Heart Rate; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D010807:Physical Endurance; D011446:Prospective Studies; D012767:Ships; D013315:Stress, Psychological / Q000097:blood / Q000150:complications* / Q000378:metabolism / Q000503:physiopathology; D013997:Time Factors
D006442:Glycated Hemoglobin; D007328:Insulin; D008055:Lipids; C517652:hemoglobin A1c protein, human