The effects of carbohydrates on mood and eating behaviour

Reid, Marie (1994) The effects of carbohydrates on mood and eating behaviour. PhD thesis, University of Glasgow.

Abstract

Some central issues from the literature on the psychophysiological effects of carbohydrate (with protein and fat as comparators) on humans are reviewed and various methodological issues are discussed. From the review chapters the main questions that emerged were: 1. Does carbohydrate, in the form of sucrose alter mood state in humans? 2. Does sucrose increase or delay hunger and subsequent food intake? 3. Does carbohydrate intake in the form of sucrose induce carbohydrate-specific hunger or carbohydrate craving? 4. Can the obese and non-obese regulate nutrient intake physiologically when cognitive cues are held constant? 5. Can humans compensate in the short-term after a sucrose preload? From these central issues a series of experiments was conducted on obese and non- obese adults where it was found that: 1. When administered blind the ingestion of sucrose did not have any significant influence on mood state in either obese or non-obese subjects. This lack of effect suggests a weak relationship between carbohydrate intake and mood, at least when moderate size preloads are given to obese and normal individuals. 2. When cognitive factors are held constant in the laboratory and preloads are administered blind, sucrose can delay hunger and subsequent food intake in both obese and normal-weight subjects in a natural environment. This is taken to be due to physiological regulation in both obese and non-obese individuals. 3. Although the delay in eating suggests some form of physiological regulation, there was no evidence of change in size of the subsequent meal. 4. There was no evidence that carbohydrate in the form of sucrose led to carbohydrate craving or increased hunger for carbohydrate-rich foods in any way. This applies to both obese and non-obese subjects. It is concluded that physiological mechanisms operate effectively in humans when psychological factors are controlled. Compensatory processes, however, do not seem to operate as effectively in the short-term. From these findings it may be argued that the obese are no more or no less responsive to internal signals than normal. It may also be argued that if sugar intake has adverse effects on hunger (i.e. carbohydrate- craving, increased hunger) then such effects are more likely to be caused by psychological factors, rather than to any physiological effects. Although there remains little doubt that nutrients do influence mood and behaviour, improvement in methodology and more elaborate methods of measuring changes in behaviour are required.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Psychobiology.
• Colleges/Schools: College of Medical Veterinary and Life Sciences
• Supervisor's Name: Hammersley, Richard
• Date of Award: 1994
• Depositing User: Enlighten Team
• Unique ID: glathesis:1994-71002
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 09 May 2019 14:28
• Last Modified: 08 Jul 2021 13:14
• Thesis DOI: 10.5525/gla.thesis.71002
• URI: https://theses.gla.ac.uk/id/eprint/71002