Diet-induced weight loss, exercise, and chronic inflammation in older, obese adults: a randomized controlled clinical trial.
BACKGROUND
Persistent, low-grade inflammation is an independent predictor of several chronic diseases and all-cause mortality.


OBJECTIVE
The intention of this study was to determine the independent and combined effects of diet-induced weight loss and exercise on markers of chronic inflammation.


METHODS
Three hundred sixteen community-dwelling, older (> or = 60 y), overweight or obese [body mass index (in kg/m2) > or = 28], sedentary men and women with radiographic evidence of knee osteoarthritis were randomly assigned to four 18-mo treatments: healthy lifestyle control, diet-induced weight loss, exercise, and diet plus exercise. The exercise intervention consisted of combined weight training and walking for 1 h 3 times/wk. The weight-loss intervention consisted of a weekly session with a registered dietitian to provide education and support for lowering energy intake.


RESULTS
The diet-induced weight-loss intervention resulted in significantly greater reductions in concentrations of C-reactive protein (P = 0.01), interleukin 6 (P = 0.009), and soluble tumor necrosis factor alpha receptor 1 (P = 0.007) than did no weight-loss treatment. Changes in soluble tumor necrosis factor alpha receptor 1 but not in C-reactive protein or interleukin 6 correlated with changes in body weight. Exercise training did not have a significant effect on these inflammatory biomarkers, and there was no significant interaction between weight loss and exercise training.


CONCLUSIONS
These findings provide evidence from a randomized controlled trial that a dietary intervention designed to elicit weight loss reduces overall inflammation in older, obese persons. Additional studies are needed to assess the effects of different modes and intensities of exercise on inflammation.
Nicklas
Barbara J
BJ
Wake Forest University School of Medicine, Winston-Salem, NC, USA. bnicklas@wfubmc.edu
Ambrosius
Walter
W
Messier
Stephen P
SP
Miller
Gary D
GD
Penninx
Brenda W J H
BW
Loeser
Richard F
RF
Palla
Shana
S
Bleecker
Eugene
E
Pahor
Marco
M
D000368:Aged; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002908:Chronic Disease; D016207:Cytokines / Q000097:blood; D015444:Exercise; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000178:diet therapy*; D015431:Weight Loss
D016207:Cytokines; D002097:C-Reactive Protein