Cognitive dietary restraint and cortisol: importance of pervasive concerns with appearance

Effects of very low-calorie ketogenic diet on hypothalamic-pituitary-adrenal axis and renin-angiotensin-aldosterone system

BACKGROUND

The hypothalamic-pituitary-adrenal (HPA) axis is a neuroendocrine system involved in controlling stress responses in humans under physiological and pathological conditions; cortisol is the main hormone produced by the HPA axis. It is known that calorie restriction acts as a stressor and can lead to an increase in cortisol production. Renin-angiotensin-aldosterone system (RAAS) is a complex endocrine network regulating blood pressure and hydrosaline metabolism, whose final hormonal effector is aldosterone. RAAS activation is linked to cardiometabolic diseases, such as heart failure and obesity. Obesity has become a leading worldwide pandemic, associated with serious health outcomes. Calorie restriction represents a pivotal strategy to tackle obesity. On the other hand, it is well known that an increased activity of the HPA may favour visceral adipose tissue expansion, which may jeopardize a successful diet-induced weight loss. Very low-calorie ketogenic diet (VLCKD) is a normoprotein diet with a drastic reduction of the carbohydrate content and total calorie intake. Thanks to its sustained protein content, VLCKD is extremely effective to reduce adipose tissue while preserving lean body mass and resting metabolic rate.

PURPOSE

The purpose of this narrative review is to gain more insights on the effects of VLCKD on the HPA axis and RAAS, in different phases of weight loss and in different clinical settings.

What Is the Profile of Overweight Individuals Who Are Unsuccessful Responders to a Low-Energy Diet? A PREVIEW Sub-study

This study was performed to evaluate the profile of overweight individuals with pre-diabetes enrolled in PREVIEW who were unable to achieve a body weight loss of ≥8% of the baseline value in response to a 2-month low-energy diet (LED). Their baseline profile reflected potential stress-related vulnerability that predicted a reduced response of body weight to a LED programme. The mean daily energy deficit maintained by unsuccessful weight responders of both sexes was less than the estimated level in successful female (656 vs. 1,299 kcal, p < 0.01) and male (815 vs. 1,659 kcal, p < 0.01) responders. Despite this smaller energy deficit, unsuccessful responders displayed less favorable changes in susceptibility to hunger and appetite sensations. They also did not benefit from the intervention regarding the ability to improve sleep quality. In summary, these results show that some individuals display a behavioral vulnerability which may reduce the ability to lose weight in response to a diet-based weight loss program. They also suggest that this vulnerability may be accentuated by a prolonged diet restriction.

Associations of perceived stress and salivary cortisol with the snack and fast-food dietary pattern in women shift workers

This study aimed to investigate the association of perceived stress and salivary cortisol levels with the snack and fast-food dietary pattern in a sample of women shift workers. We conducted a cross-sectional study of 539 women aged 18-53 years working in the production line of a poultry processing plant. Stress was assessed with the 10-item Perceived Stress Scale (PSS-10) and by salivary cortisol levels (immediately after waking and upon returning home from work). Dietary patterns were identified by principal component analysis. We used linear and Poisson regression models to assess multivariable-adjusted associations of perceived stress and salivary cortisol levels with the snack and fast-food dietary pattern. After adjustments, women with higher PSS-10 scores had a 28% higher probability (95% confidence interval, 1.04-1.56) of consuming snacks/fast food. Mean (SD) waking cortisol levels were inversely associated with quartiles of the dietary pattern: Q1, 6.63 (0.43) nmol/L; Q2, 6.00 (0.38) nmol/L; Q3, 5.62 (0.40) nmol/L; and Q4, 5.29 (0.35) nmol/L (p = 0.019). Perceived stress was not associated with salivary cortisol levels. The work shift was not associated with perceived stress or cortisol levels. This study demonstrated an association of psychological and physiological measures of stress with a dietary pattern characterized by high intakes of hyper-palatable, energy-dense, ready-to-eat foods among women shift workers.

Do thoughts about dieting matter? Testing the relationship between thoughts about dieting, body shape concerns, and state self-esteem

BACKGROUND AND OBJECTIVES

Dieters are likely primed to think about their diet throughout the day (e.g., as they feel hungry). However, prior research has not tested whether and how thinking about dieting might have negative effects, like poor self-esteem and body shape concerns.

METHODS

We experimentally primed dieters' thoughts about their diets and tested whether: 1) dieting thoughts are related to poor state self-esteem through body shape concerns; and 2) dieting thoughts are related to body shape concerns through poor state self-esteem. Dieting participants (N = 225) were randomly assigned to complete a dieting or neutral prime.

RESULTS

Unexpectedly, there was a different pattern of results across male (n = 72) and female (n = 144) dieters. When accounting for body shape concerns, males primed to think about dieting (vs. neutral condition) reported greater state self-esteem. Further, the dieting prime indirectly led to lower body shape concerns through greater state global self-esteem. However, for females, the dieting prime indirectly led to poorer state self-esteem through its effects on body shape concerns.

LIMITATIONS

The sample was collected online and was predominantly female and Caucasian. Other limitations include self-report of dieting status and body mass index.

CONCLUSIONS

The findings suggest that for males, thoughts about dieting may actually be associated with greater state self-esteem, which may indirectly predict lower body shape concerns. In contrast, for females, when thoughts about dieting activate body shape concerns, poorer state self-esteem may follow. These results highlight important, potentially gender-specific relationships between thoughts about dieting, body shape concerns, and state self-esteem.

Changes in body image during a 6-month lifestyle behaviour intervention in a sample of overweight and obese individuals

BACKGROUND

Individuals with long-term chronic body image dissatisfaction may experience excessive stress and negative cognitions and feelings. Changes in negative cognition about body image are often reported as outcomes of obesity treatment. In turn, body image dissatisfaction also influences behavioural adherence and success in weight loss.

OBJECTIVES

The purpose of the present study was to elucidate psychological changes during 6 months of lifestyle behaviour intervention and the association of these changes with actual weight loss.

METHODS

The study examined associations between body image dissatisfaction and obesity treatment-related variables among 33 overweight and obese adults (age = 38.9 ± 6.5 years) participating in a 6-month diet and exercise weight loss intervention. Measurements of body image dissatisfaction and anthropometric variables were taken at baseline and after 6-months.

DISCUSSION

Significant improvements were observed in all physical variables (e.g. weight, percentage of body fat mass, waist and hip circumference) after intervention. Body image dissatisfaction improved significantly over the treatment, and these changes were associated with changes in obesity indicators.

CONCLUSIONS

Changes in weight and body image probably influence each other dynamically. Results from this study support the inclusion of cognitive intervention aimed at improving body image in weight management programs.

Impact of Experimentally Induced Cognitive Dietary Restraint on Eating Behavior Traits, Appetite Sensations, and Markers of Stress during Energy Restriction in Overweight/Obese Women

Weight loss has been associated with changes in eating behaviors and appetite sensations that favor a regain in body weight. Since traditional weight loss approaches emphasize the importance of increasing cognitive dietary restraint (CDR) to achieve negative energy imbalance, it is difficult to untangle the respective contributions of energy restriction and increases in CDR on factors that can eventually lead to body weight regain. The present study aimed at comparing the effects of energy restriction alone or in combination with experimentally induced CDR on eating behavior traits, appetite sensations, and markers of stress in overweight and obese women. We hypothesized that the combination of energy restriction and induced CDR would lead to more prevalent food cravings, increased appetite sensations, and higher cortisol concentrations than when energy restriction is not coupled with induced CDR. A total of 60 premenopausal women (mean BMI: 32.0 kg/m2; mean age: 39.4 y) were provided with a low energy density diet corresponding to 85% of their energy needs during a 4-week fully controlled period. At the same time, women were randomized to either a condition inducing an increase in CDR (CDR+ group) or a condition in which CDR was not induced (CRD- group). Eating behavior traits (Three-Factor Eating Questionnaire and Food Craving Questionnaire), appetite sensations (after standardized breakfast), and markers of stress (Perceived Stress Scale; postawakening salivary cortisol) were measured before (T = 0 week) and after (T = 4 weeks) the 4-week energy restriction, as well as 3 months later. There was an increase in CDR in the CDR+ group while no such change was observed in the CDR- group (p=0.0037). No between-group differences were observed for disinhibition, hunger, cravings, appetite sensations, perceived stress, and cortisol concentrations. These results suggest that a slight increase in CDR has no negative impact on factors regulating energy balance in the context of energy restriction.

Body image dissatisfaction in pregnant and non-pregnant females is strongly predicted by immune activation and mucosa-derived activation of the tryptophan catabolite (TRYCAT) pathway

OBJECTIVES

The aim of the present study is to delineate the associations between body image dissatisfaction in pregnant women and immune-inflammatory biomarkers, i.e., C-reactive protein (CRP), zinc and IgA/IgM responses to tryptophan and tryptophan catabolites (TRYCATs).

METHODS

We assessed 49 pregnant and 24 non-pregnant females and assessed Body Image Satisfaction (BIS) scores at the end of term (T1), and 2-4 days (T2) and 4-6 weeks (T3) after delivery. Subjects were divided in those with a lowered BIS score (≤ 3) versus those with a higher score.

RESULTS

Logistic regression analysis showed that a lowered T1 BIS score was predicted by CRP levels and IgA responses to tryptophan (negative) and TRYCATs (positive), perinatal depression, body mass index (BMI) and age. The sum of quinolinic acid, kynurenine, 3-OH-kynurenine and 3-OH-anthranilic acid (reflecting brain quinolinic acid contents) was the single best predictor. In addition, a large part of the variance in the T1, T2 and T3 BIS scores was explained by IgA responses to tryptophan and TRYCATs, especially quinolinic acid.

CONCLUSIONS

Body image dissatisfaction is strongly associated with inflammation and mucosa-derived IDO activation independently from depression, pregnancy, BMI and age. IgA responses to peripheral TRYCATs, which determine brain quinolinic acid concentrations, also predict body image dissatisfaction.

Prolonged perceived stress and saliva cortisol in a large cohort of Danish public service employees: cross-sectional and longitudinal associations

Purpose

It is well known that acute stress can lead to a transient increase in cortisol secretion, but the effects of prolonged stress on cortisol secretion are uncertain. This study examines the cross-sectional and longitudinal associations between prolonged perceived stress and salivary cortisol.

Methods

In 2007, 4467 Danish public service employees participated in a study of stress and mental health, and 3217 participated in a follow-up in 2009. Perceived stress during the past 4 weeks was assessed by Cohen’s four item perceived stress scale. Participants were asked to collect saliva 30 min after awakening and at approximately 20:00 in the evening. The cortisol dependence on perceived stress was examined in regression analyses adjusted for effects of potential confounders. We adjusted for a large variation in saliva sampling times by modelling the time trajectory of cortisol concentrations in the morning and in the evening and examined if they were influenced by perceived stress.

Results

Perceived stress had no statistically significant effects on the level or time trajectory of morning or evening cortisol, neither cross-sectionally nor longitudinally. The 1 month prevalence of frequently perceived stress was low, approximately 2.5%.

Conclusion

Our results did not support the hypothesis that prolonged perceived stress is associated with the level or time trajectory of morning or evening salivary cortisol.

Electronic supplementary material

The online version of this article (doi:10.1007/s00420-017-1241-z) contains supplementary material, which is available to authorized users.

Bone parameters in relation to attitudes and feelings associated with disordered eating in oligo-amenorrheic athletes, eumenorrheic athletes, and nonathletes

OBJECTIVES

Disordered eating may negatively impact bone in athletes. However, it is not known whether this effect is independent of the associated amenorrhea and relative hypercortisolemia. We aimed to compare attitudes, feelings, and cognitions associated with disordered eating using the Three-Factor Eating Questionnaire (TFEQ) and Eating Disorder Inventory-2 (EDI-2) in normal-weight oligomenorrheic athletes (OA), eumenorrheic athletes (EA), and nonathletes, and determine the associations with bone independent of confounders.

METHOD

109 OA, 39 EA, and 36 nonathletes (14-25 years) completed the TFEQ and EDI-2. Dual-energy X-ray absorptiometry was used to assess spine bone mineral density (BMD), and high-resolution pQCT to assess radius microarchitecture. We measured integrated cortisol (q 20', 11 PM-7 AM), bone formation (procollagen Type 1 N-terminal propeptide, P1NP), and resorption (C-telopeptide, CTX) markers in a subset.

RESULTS

OA had lower spine BMD Z-scores than EA. Cognitive eating restraint (CER), drive for thinness (DT), ineffectiveness, and interoceptive awareness (IA) were higher in OA than EA (p < 0.05); CER was higher in OA versus nonathletes (p = 0.03). Pulsatile cortisol was positively associated with DT, ineffectiveness, and IA (p < 0.03). CER was inversely associated with BMD Z-scores and P1NP, and ineffectiveness with radius cross-sectional area even after controlling for age, BMI, amenorrhea duration, and cortisol (p < 0.03).

DISCUSSION

Higher CER in athletes independently predicts lower BMD.

Activation in inhibitory brain regions during food choice correlates with temptation strength and self-regulatory success in weight-concerned women

Food choices constitute a classic self-control dilemma involving the trade-off between immediate eating enjoyment and the long term goal of being slim and healthy, especially for weight-concerned women. For them, decision-making concerning high (HE) and low energy (LE) snacks differs when it comes to the need for self-control. In line, our first study aim was to investigate which brain regions are activated during food choices during HE compared to LE energy snacks in weight-concerned women. Since it is particularly difficult to resist HE snacks when they are very tasty, our second aim was to investigate in which brain regions choice-related activation varies with the food's tastiness. Our third aim was to assess in which brain regions choice-related activation varies with individual differences in self-regulatory success. To this end, 20 weight-concerned women indicated for 100 HE or LE snacks whether they wanted to eat them or not, while their brains were scanned using fMRI. HE snacks were refused more often than equally-liked LE snacks. HE snack choice elicited stronger activation in reward-related brain regions [medial to middle orbitofrontal cortex (OFC), caudate]. Highly tasty HE snacks were more difficult to resist and, accordingly, activation in inhibitory areas (inferior frontal gyrus, lateral OFC) was negatively associated with tastiness. More successful self-controllers showed increased activation in the supplementary motor area during HE food choices. In sum, the results suggest that HE snacks constitute a higher reward for weight-concerned women compared to (equally-liked) LE snacks, and that activation during food choice in brain regions involved in response inhibition varied with tastiness and individual differences in self-regulatory success. These findings advance our understanding of the neural correlates of food choice and point to new avenues for investigating explanations for self-regulatory failure.

Sweet lies: neural, visual, and behavioral measures reveal a lack of self-control conflict during food choice in weight-concerned women

Despite their intentions, weight-concerned individuals generally fail to control their eating behavior. However, it is unknown whether this failure is due to a lack of effortful self-control, or to not experiencing an internal conflict between weight goals and food temptations. The present study used fMRI, eye tracking and reaction times to assess the degree of conflict experienced by weight-concerned women during food choices that posed either a self-control dilemma (i.e., requiring a choice between healthy and palatable foods), or not. Contrary to the common assumption in self-control theory that food choices posing a self-control dilemma evoke internal conflict, we found that choices requiring self-control induced no conflict, as demonstrated by lower reaction times, fixation durations, number of gaze switches between snacks, and lower activation of the anterior cingulate cortex. Our results suggest that self-control failure might be due to a lack of experienced conflict, rather than to failing to act upon the perception of such conflict. This implies that effectiveness of weight maintenance interventions might be improved if they also focus on increasing the ability to detect a self-control dilemma, in addition to the current focus on increasing self-regulatory capacity.

Impact of negative cognitions about body image on inflammatory status in relation to health

OBJECTIVE

Evidence suggests that body dissatisfaction may relate to biological processes and that negative cognitions can influence physical health through the complex pathways linking psychological and biological factors.

DESIGN

The present study investigates the relationships between body image satisfaction, inflammation (cytokine levels), aerobic fitness level and obesity in 96 middle-aged men and women (48 normal and 48 overweight). All participants underwent measurements of body satisfaction, body composition, serological measurements of inflammation and aerobic capabilities assessment.

RESULTS

Body image dissatisfaction uniquely predicted inflammation biomarkers, C-reactive protein and tumour necrosis factor-α, even when controlled for obesity indicators. Thus, body image dissatisfaction is strongly linked to inflammation processes and may promote the increase in cytokines, representing a relative metabolic risk, independent of most traditional risk factors, such as gender, body mass index and intra-abdominal (waist to hip ratio) adiposity.

CONCLUSION

Results highlight the fact that person's negative cognitions need to be considered in psychologically based interventions and strategies in treatment of obesity, including strategies for health promotion. Results contribute to the knowledge base of the complex pathways in the association between psychological factors and physical illness and some important attempts were made to explain the psychological pathways linking cognitions with inflammation.

The construct validity of the Restraint Scale among mainland Chinese women

This study aimed to test the construct validity of the newly developed Chinese version of the Revised Restraint Scale (RRS) in two separate female samples from Chinese universities (n(1) = 171; n(2) = 158). The RRS is the most widely used measure of restricted eating for the purpose of achieving or maintaining a desired weight. Results showed that the 10-item Chinese RRS comprised of two subscales of concern dieting (CD) and weight fluctuation (WF), which together accounted for 53.01% of the total variance. Confirmative factor analysis supported this two-factor model as an acceptable model (χ(2)/df = 1.545, p < 0.001; RMSEA=0.059, GFI=0.938, and CFI=0.935). Cronbach's alpha coefficients were 0.77 for RRS, 0.71 for CD and 0.66 for WF. Significant correlations were shown between RRS and its subscales ((rRRS-CD) = 0.894, p < 0.01; r(RRS-WF) = 0.850, p < 0.01; r(CD-WF) = 0.523, p < 0.01). Moreover, RS significantly correlated with the Three-Factor Eating Questionnaire-R (TFEQ-R), the Dutch Eating Behaviour Questionnaire-R (DEBQ-R), the Fatness Concern (FC) and the body measure index (BMI) (r = 0.548, p < 0.01; r = 0.631, p < 0.01; r = 0.620, p < 0.01; r = 0.351, p < 0.01, respectively). In sum, the RS has stable factor structure, acceptable internal consistency and satisfactory convergent reliability among female Chinese college students. The adapted scale may serve as a useful tool for identifying restrained and unrestrained eaters among Chinese women and may be particularly useful in assessing eating restraint before and after prevention and intervention programs.

Associations between weight-related eating behaviors and adiposity in postmenopausal Japanese American and white women

The purpose of this study was to test the associations between cognitive and psychological eating behavior traits and detailed measures of adiposity and body fat distribution using imaging-based methods in a cross-sectional study. Eating behavior traits (compensatory and routine restraint, external eating, and emotional eating) were assessed using the validated Weight-Related Eating Questionnaire, and measures of adiposity using anthropometry, dual energy X-ray absorptiometry (DXA), and magnetic resonance imaging (MRI). Each adiposity outcome of interest (total fat, ratio of trunk fat to periphery fat, visceral and subcutaneous fats as % of abdominal area, and % liver fat) was regressed on the four eating behaviors while adjusting for age and race/ethnicity. This study included a total of 60 postmenopausal Japanese American (n=30) and white (n=30) women (age: 60-65 years, BMI: 18.8-39.6 kg/m(2)). Weight-related eating behavior traits did not differ by ethnicity. Higher external eating scores were associated with measures of total adiposity, including higher BMI (β=0.36, p=0.02) and DXA total fat mass (β=0.41, p=0.001), and with MRI abdominal subcutaneous fat (β=0.55, p=0.001). Higher routine restraint scores were associated with visceral adiposity (β=0.42, p=0.04). Our findings suggest that different weight-related eating behavior traits might increase not only total adiposity but also abdominal and visceral fat deposition associated with higher metabolic risks. Future research, preferably in a prospective study of men and women and including biomarkers related to psychological stress, will be needed to explore potential underlying biological mechanisms.

Anxious attachment style and salivary cortisol dysregulation in healthy female children and adolescents

BACKGROUND

Attachment style has been linked with basal cortisol secretion in healthy adult women. We investigated whether dysregulation in basal cortisol secretion may be evident in younger healthy females.

METHODS

Sixty healthy females aged 9-18 years (mean 14.16, SD ± 2.63 years) participated in the Attachment Style Interview (ASI). Eight saliva samples, synchronised to awakening, were collected per day on two consecutive weekdays to examine the cortisol awakening response (CAR) and the subsequent diurnal decline.

RESULTS

Participants exhibiting an anxious attachment style had higher cortisol levels on awakening, in contrast to those who were securely attached. The anxious insecure group also showed an attenuated CAR compared to all other participants. Attachment style groups did not differ in cortisol secretion over the remainder of the day.

CONCLUSIONS

These findings indicate that the same pattern of cortisol dysregulation associated with disorder in adulthood manifests as a function of anxious (but not avoidant) insecure attachment style in females during healthy childhood and adolescence.

The relationship between 24-h urinary cortisol and bone in healthy young women

BACKGROUND

Cortisol within the normal range has been associated with reduced bone density in the elderly, but little is known about this relationship in healthy young women.

PURPOSE

The purpose of this study is to assess whether 24-h urinary free cortisol excretion (UFC) is related to bone density in 132 healthy, non-obese, regularly menstruating women, aged 19-35.

METHOD

Participants completed questionnaires (food frequency, demographics, physical activity, dietary restraint, perceived stress, and daily stress) and a 24-h urine collection. UFC was determined by high-throughput liquid chromatography and tandem mass spectrometry. Anthropometrics were completed and a dual energy X-ray absorptiometry scan measured areal bone mineral density (aBMD, g/cm(2)) and bone mineral content (BMC, g) at the lumbar spine (L1-4), hip, and total body (TB) as well as total body lean (LBM) and fat mass.

RESULTS

aBMD and BMC were significantly positively associated with height, LBM, physical activity, calcium intake, and duration of previous oral contraceptive use (except L1-4) and negatively with perceived stress. UFC was not correlated with any measured variables except urine volume (r = 0.17, p = 0.046). After adjusting for urine volume, height, LBM, ethnicity, and prior oral contraceptive use, UFC was significantly inversely associated with TB BMC (r = -0.30, p < 0.001) and aBMD (r = -0.27, p = 0.003), L1-4 aBMD (r = -0.19, p = 0.035) and BMC (r = -0.18, p = 0.049), and hip BMC (r = -0.23, p = 0.011). Further adjustment for sport activity, calcium intake and perceived stress did not change these relationships meaningfully except that L1-4 became nonsignificant (p < 0.07).

CONCLUSION

Cortisol within the normal range appears to have a minor negative influence on bone density in healthy young women.

A prospective exploration of cognitive dietary restraint, subclinical ovulatory disturbances, cortisol, and change in bone density over two years in healthy young women

CONTEXT

Cross-sectional studies have found associations among elevated cognitive dietary restraint (CDR), increased ovulatory disturbances, and lower bone mass, possibly mediated by cortisol.

OBJECTIVE

To determine whether healthy young women with higher CDR have more menstrual cycles with subclinical ovulatory disturbances (SOD), elevated 24-h urinary free cortisol (UFC), and less positive 2-yr areal bone mineral density change (Delta-aBMD).

DESIGN, SETTING, AND PARTICIPANTS

We conducted a 2-yr longitudinal study of 123 healthy, community-dwelling, nonobese, regularly menstruating women aged 19-35 yr.

MAIN OUTCOME MEASURES

Key variables were Three Factor Eating Questionnaire Restraint score, percent of cycles with anvoluation and/or luteal phase length <10 d (%SOD), UFC, and Delta-aBMD at the lumbar spine (L1-L4), total hip, and whole body. Anthropometrics, general stress, physical activity, and energy intake were measured. Adjusting for potential confounders, differences were examined by general linear modeling using median split of CDR score and %SOD.

RESULTS

Women with higher CDR had higher %SOD (56 vs. 34%, P < 0.001) and higher UFC (28.0 vs. 24.0 microg/d, P = 0.021). Delta-aBMD did not differ by CDR. Women with higher %SOD had less positive Delta-aBMD at L1-L4 (0.7 vs. 1.9%, P = 0.034) and hip (-0.6 vs. 0.9%, P = 0.001), and higher CDR score (8.7 vs. 7.1, P = 0.04). Physical activity, general stress, body mass index, and energy intake did not explain differences by CDR or %SOD. UFC was not associated with %SOD or Delta-aBMD.

CONCLUSION

Women with more frequent SOD reported higher CDR and experienced less positive Delta-aBMD. Although women with higher CDR had higher UFC, the mechanism linking CDR, SOD, and aBMD is not clear.

Hyperactivity of the HPA axis is related to dietary restraint in normal weight women

The objective of our study was to investigate the relationship between hypothalamus/pituitary/adrenal (HPA) axis functioning and dietary restraint in normal weight (BMI between 20 and 25 kg/m(2)) men and women. We therefore assessed in 38 men and 38 women HPA axis functioning, through measuring 5-hour cortisol exposure and cortisol feedback functioning through a dexamethasone (4 mg) suppression test. Eating behavior was assessed through the Three Factor Eating Questionnaire and body composition through hydro densitometry and deuterium dilution method. No relationship between HPA axis functioning and dietary restraint was found in men. Normal weight women with a restraint score >/=9 showed increased cortisol concentrations over a 5-hour time period, increased cortisol concentrations after a dexamethasone (4 mg) suppression test, higher BMI, and higher body fat percentage, when compared to women with a restraint score <9. Moreover, a positive relationship was found between cortisol concentrations over a 5-hour time period and dietary restraint in combination with the disinhibition score (R(2)=0.23, p<0.001). We conclude that in normal weight women hyperactivity of the HPA-axis is related to dietary restraint especially in combination with disinhibition.

Dietary restraint and telomere length in pre- and postmenopausal women

BACKGROUND

Leukocyte telomere shortening can serve as a biomarker of aging, as telomere length (TL) can decline with age and shortening is positively associated with morbidity and mortality. It is therefore important to identify psychological and behavioral factors linked to accelerated telomere shortening. Stress and poorer metabolic health (greater adiposity, insulin resistance, and cortisol) correlate with shorter telomeres. Self-reported dietary restraint (DR), defined as chronic preoccupation with weight and attempts at restricting food intake, is linked to greater perceived stress, cortisol, and weight gain, when assessed in community studies (versus in weight loss programs).

OBJECTIVE

To test for an association between DR and TL in healthy women across a range of ages.

METHODS

We examined whether DR is linked to TL in two samples, one of premenopausal women (aged 20-50 years;N = 36) and one of postmenopausal women (aged 53-69 years; N = 20).

RESULTS

In both samples, higher levels of DR were associated with shorter leukocyte TL, independent of body mass index, smoking, and age.

CONCLUSIONS

Chronic DR, as assessed by self-report (i.e. not caloric restriction), may be a risk factor for premature telomere shortening. Potential mechanisms are discussed.