The Effects of a High Fat, Low Carbohydrate or a Low Fat, High Carbohydrate Diet on Mood Cognition and Appetite
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Nottingham
- Enrollment
- 20
- Locations
- 1
- Primary Endpoint
- Clear-headedness
Study Overview
Brief Summary
A previous study has found that the consumption of a high fat, low carbohydrate meal results in increased feelings of calmness, friendliness and an increase in subjective energy levels in comparison to a low fat, high carbohydrate meal. The purpose of this study is to investigate whether a high fat, low carbohydrate diet for a longer duration (of 2 weeks) can enhance or sustain these changes in comparison to a low fat, high carbohydrate meal.
Detailed Description
Research has shown that consuming breakfasts high in either fat or carbohydrates can affect a persons memory, mood and ability to concentrate (Benton & Parker, 1998, Politt & Mathews, 1998). Our previous study investigating the effect of a high fat, low carbohydrate (HFLC) meal in comparison to a low fat, high carbohydrate (LFHC) meal found that the HFLC meal resulted in significantly increased feelings of calmness, friendliness and a reduction in feelings of anger, and an increase in subjective energy levels in comparison to a LFHC meal. However, the chronic effects of a HFLC or LFHC diet has not been studied. This purpose of this study is to investigate whether a 2 week diet high in either fat or carbohydrates improves cognition/memory and mood. It is hypothesised that the prolonged feeding of a HFLC diet will attenuate the response seen after a HFLC meal was provided.
Twenty healthy women are required to attend the School of Biomedical Sciences on seven occasions.
The first visit will involve screening tests for suitability for inclusion in the study and written, informed consent will be obtained. Weight, height and blood pressure will be measured and a 5ml blood sample will be collected for full blood count, urea, electrolytes and random blood glucose assessment. Subjects will be asked to complete questionnaires regarding general health, eating habits, mood and medical history. Following the screening visit, subjects will be asked to record their habitual food intake and physical activity pattern for a 3 day period (2 weekdays and 1 weekend day. They will then attend the laboratory on 6 further occasions, once for a familiarisation visit and for the 5 study visits.
The familiarisation visit is required to ensure that subjects are comfortable and familiar with using the cognitive tests which will be administered.
Subjects will be provided with a menu of foods to consume as their evening meal prior to study visits, based on 30% total energy expenditure. This meal will be based on foods the subject recorded in the completed food diary and will contain approximately 15% of total energy from protein, 55% from carbohydrate and 30% from fat. Before study visits subjects will be instructed to consume this standardised meal as their last meal of the day before 20.00 on the previous evening. After they have consumed this meal they are instructed not to consume any foods or drinks apart from water until they arrive at the lab.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Basic Science
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 45 Years (Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •BMI 18.5-25kg/m2
- •aged 18-45 years
- •regular breakfast eaters
- •regular menstrual cycle
Exclusion Criteria
- •Significant gastrointestinal disease, gastrointestinal surgery, diabetes or any other significant major medical morbidity
- •History of significant eating disorder (anorexia, bulimia)
- •Habitual dietary protein intake >20% of total energy intake
- •pregnancy or breast feeding
- •anaemia (Hb <11.5g/dL)
- •random blood glucose concentration >8mmol/l
- •no medication use other than contraception
- •significant weight loss/gain (>14lb in previous 3 months)
Arms & Interventions
High fat, low carbohydrate diet
Fats intake 55% , Protein 17% and carbohydrate 28% of total energy
Intervention: High Fat Low Carbohydrate Diet (Other)
Low fat, high carbohydrate diet
Fat intake 20%, Protein 17% and carbohydrate 63% of total energy intake
Intervention: Low fat High Carbohydrate Diet (Other)
Outcomes
Primary Outcomes
Clear-headedness
Time Frame: after 2 week intervention period
Subjective mood measurement, assessed using visual analogue scale, in response to a test meal
Secondary Outcomes
- Reaction time(after 2 week intervention)
Investigators
Elizabeth Simpson
Senior Research Fellow
University of Nottingham