CALIBER Phase 1: A Pilot Study in Normal-weight and Overweight Adults.
Condition: Cardiometabolic Risk
MeSH terms: Overweight
Study type: Interventional

Summary: 
      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.
    

Detailed description: 
      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.
    

Intervention name(s): Low-carbohydrate, high-fat; High-carbohydrate, moderate-fat
Intervention type(s): Other; Other
Intervention description(s): Participants following low-carbohydrate, high-fat diet for 8 weeks.; Participants following high-carbohydrate, moderate-fat diet (UK dietary guidelines) for 8 weeks.
Other intervention name(s): CALIBER LCHF; CALIBER HCMF
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Randomised pilot study
Masking: None (Open Label)
Primary purpose: Prevention