Using Behavioural Reasoning Theory to Explore Reasons for Dietary Restriction: A Qualitative Study of Orthorexic Behavioural Tendencies in the UK

Orthorexia Nervosa (ON) has gained increased attention in academia since 1997. However, like other “Exia” conditions, there is debate around its inclusion in the Diagnostic and Statistical Manual of Mental Disorders. This study aimed to examine the experiences of those following a diet indicative of ON in the United Kingdom. This information is essential to the development of diagnostic criteria and classification of ON. Behavioural Reasoning Theory was used to explore reasons contributing to the development of ON. Ten individuals (two males and eight females), aged 23–35 years, took part in semi-structured interviews. Inductive thematic analysis was used to analyse the results. Four themes emerged from the data—journey, social, rules/control, and ethical considerations which highlighted contributing factors to the development of ON behaviours, the impact of these behaviours on individuals' social lives, and a strive for control. These findings are the first to suggest that ON involves a more complex set of behaviours than current definitions and proposed diagnostic criteria suggest and highlight the need to consider a variety of reasons for restricted diet when developing diagnostic criteria, screening tools, and classification in the DSM.

Assessing psychological and nutritional impact of suspected orthorexia nervosa: a cross-sectional pilot study

BACKGROUND

To date, research on the dietary patterns of individuals with potential orthorexic symptoms is lacking. This cross-sectional pilot study aimed to explore the feasibility of assessing dietary patterns with psychological traits and states of individuals with possible orthorexic tendencies.

METHODS

Dietary intakes of 10 individuals (two males and eight females) were assessed using 24-h recall. Mean age of participants was 28.3 years; mean body mass index was 21.2 kg m^-2 . Nutrient intakes were compared with current dietary guidelines and the Eatwell Guide (Public Health England, 2016). Participants completed the ORTO-15, the Eating Attitude Test (EAT-26), the Obsessive-Compulsive Inventory-Revised edition (OCI-R), Paulhus's Spheres of Control (SoC), the Rosenberg's Self-Esteem Scale (RSES) and the Multidimensional Body-Self Relations Questionnaire (MBSRQ).

RESULTS

High levels of disparity across participants' psychometric scores and 24-h recall results were observed. There was no single pattern of self-imposed dietary restrictions among participants. Described dietary practices failed to meet the guidelines for several nutrients.

CONCLUSIONS

The results of this pilot study suggest that an extensive investigation of the diets of individuals with possible orthorexic tendencies in a large-scale study would contribute to the understanding of this condition. In addition, the use of multiple psychometric instruments is recommended for diagnosing orthorexic nervosa.

Effects of orthodox religious fasting versus combined energy and time restricted eating on body weight, lipid concentrations and glycaemic profile

For seven weeks, 37 overweight adults followed a hypocaloric diet based on Orthodox Fasting (OF). A hypocaloric, time restricted eating (TRE) plan (eating between 08:00 to 16:00 h, water fasting from 16:00 to 08:00 h) was followed by 23 Body Mass Index (BMI)-matched participants. Anthropometric, glycaemic and inflammation markers and serum lipids were assessed before and after the diets. Both OF and TRE groups demonstrated reductions in BMI (28.54 ± 5.45 vs 27.20 ± 5.10 kg/m², p < 0.001 and 26.40 ± 4.11 vs 25.81 ± 3.78 kg/m² p = 0.001, respectively). Following the intervention, the OF group presented lower concentrations of total and low-density lipoprotein-cholesterol, compared with the pre-fasting values (178.40 ± 34.14 vs 197.17 ± 34.30 mg/dl, p < 0.001 and 105.89 ± 28.08 vs 122.37 ± 29.70 mg/dl, p < 0.001, respectively). Neither group manifested significant differences in glycaemic and inflammatory parameters. Our findings suggest that OF has superior lipid lowering effects than the TRE pattern.

Rat sodium iodide symporter allows using lower dose of 131I for cancer therapy

Efficient gene delivery is a critical obstacle for gene therapy that must be overcome. Until current limits of gene delivery technology are solved, identification of systems with bystander effects is highly desirable. As an anticancer agent, radioactive iodine (131)I has minimal toxicity. The physical characteristics of (131)I decay allow radiation penetration within a local area causing bystander killing of adjacent cells. Accumulation of (131)I mediated by the sodium iodide symporter (NIS) provides a highly effective treatment for well-differentiated thyroid carcinoma. Other types of cancer could also be treated by NIS-mediated concentration of lethal (131)I radiation in tumor cells. Our group and others previously reported that a significant antitumor effect in mice was achieved after adenoviral delivery of rat or human NIS gene following administration of 3 mCi of (131)I. We have also demonstrated 5-6-fold greater uptake of (125)I by rat NIS over human NIS in human cancer cells. Recently, we reported the capability of the rat NIS and (131)I to effectively induce growth arrest of relatively large tumors (approximately 800 mm(3)) in an animal model. In the present work tumor growth inhibition was achieved using adenoviral delivery of the rat NIS gene and 1 mCi of (131)I (one-third of the dose used in earlier reports). We also demonstrated that a higher concentration of (123)I was accumulated in the NIS-expressing tumors than in the thyroid 20 min after radioiodine administration. The highest intratumoral radioiodine concentration was observed along the needle track; however, the rat NIS-(131)I effectively induced growth arrest of tumor xenografts in mice through its radiological bystander effect. Importantly, the rat NIS allowed reducing the injected radioiodine dose by 70% with the same antitumor efficacy in pre-established tumors. These results suggest that the rat NIS gene may be advantageous compared to the human gene in its ability to enhance intratumoral (131)I uptake.