Pilot study to compare the impact of following a low-carbohydrate, high-fat diet versus following a high-carbohydrates, moderate-fat diet (UK dietary guidelines) on cardiometabolic risk markers and associated behaviours in a normal-weight and overweight adult population.
Cardiometabolic diseases (CMD), such as type 2 diabetes and cardiovascular disease (CVD), are globally amongst the highest contributors to morbidity and mortality with high (cost) implications to the overall economy and health care systems. A number of risk markers have been associated with CMDs, including blood serum markers, low levels of lean mass and high levels of body fat, including increased waist circumference. Dietary factors and nutritional status have long been linked with specific markers of cardiometabolic (CM) risk. The quantity and quality of dietary carbohydrates has been associated with increased serum triglycerides levels, increased body fat mass, increased waist circumference and visceral fat around the organs in particular. They also seem to increase food cravings. Whilst official dietary guidelines in the UK and elsewhere still recommend a high carbohydrate and low fat diet as standard, these recommendations have increasingly been challenged. Evidence has been mounting that very-low carbohydrate (ketogenic) and low carbohydrate diets can ameliorate CM risk factors, especially when a personalised rather than a one-size-fits-all approach is being taken. Response to carbohydrate load and adherence to dietary interventions can vary widely dependent on individual substrate and energy metabolism and insulin-resistant status. The majority of dietary interventions with ketogenic and low-carbohydrate diets has focused on weight loss as the primary outcome in overweight and obese individuals. However, in recent years evidence has been mounting that the location and quality of adipose tissue (AT) play a more important role in manifestation of CM risk than quantity of AT alone. Detrimental health behaviours, such as low-quality diet and low levels of physical activity seem to be important contributors to this. Further studies can provide vital insights into the links between diet, location-specific adipose tissue, CM risk factors and health-related behaviours. Therefore this 8-weeks randomised pilot study will investigate the impact of either following a low-carbohydrate, high-fat diet versus following a high-carbohydrates, moderate-fat diet (UK dietary guidelines) on cardiometabolic risk markers and associated behaviours in a normal-weight and overweight adult population aged 19 - 64 at potential risk of CMD.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
15
Participants following low-carbohydrate, high-fat diet for 8 weeks.
Participants following high-carbohydrate, moderate-fat diet (UK dietary guidelines) for 8 weeks.
Liverpool John Moores University
Liverpool, Merseyside, United Kingdom
Serum lipid profile
Total cholesterol, HDL-C, LDL-C, non-HDL cholesterol, small-dense LDL-C and triglycerides measured in mmol/L
Time frame: 8 weeks
Blood glucose
Measured in mmol/L
Time frame: 8 weeks
Systolic and diastolic blood pressure
Measured in mmHg
Time frame: 8 weeks
Inflammatory markers, such as CRP
Measured in mg/L
Time frame: 8 weeks
Adiponectin
Measured in μg/mL
Time frame: 8 weeks
Fibroblast growth factor 21 (FGF21).
Measured in pg/mL
Time frame: 8 weeks
Tumor necrosis factor alpha and Interleukin 6
Measured in μg/mL
Time frame: 8 weeks
Body composition - Bioelectrical impedance
Lean mass, fat mass and adipose tissue location and distribution
Time frame: 8 weeks
Body composition - Anthropometrics
Waist, hip, neck, thigh and calf circumference measured in cm
Time frame: 8 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Clinical traditional and emerging markers of dietary intake
Fibroblast growth factor 21 and serum metabolites
Time frame: 8 weeks
Food cravings
Measured via self-reported questionnaire
Time frame: 8 weeks
Satiety
Assessed via serum leptin levels (ng/mL)
Time frame: 8 weeks
Cognition
Assessed via self-reported questionnaire
Time frame: 8 weeks
Impact on physical activity patterns
Assessed via accelerometry
Time frame: 8 weeks
Adherence to assigned diet
Measured via 4-day food diaries
Time frame: 8 weeks
Adherence to dietary guidelines
Measured via diet quality score assessment
Time frame: 8 weeks
Adherence to low-carbohydrate diet
Measured via blood ketones (mmol/L)
Time frame: 8 weeks
Adherence to fibre recommendations
Measured via structured questionnaires
Time frame: 8 weeks
Adherence to taking dietary supplement for low-carbohydrate, high-fat group
Measured via counting of number of multi-vitamin and mineral supplements consumed
Time frame: 8 weeks
Experience with either low-carbohydrate, high-fat or high-carbohydrate, moderate-fat diet
Assessed via semi-structured interview
Time frame: 8 weeks