Fructose and Ethnic Differences Study (FED Study)
Condition: Healthy
Study type: Interventional

Summary: 
      In the UK, people of black West African and Caribbean's tend to have healthier blood
      cholesterol and blood fat levels, as well as lower incidence of heart disease/heart attack.
      But rates of heart disease are now rising in young African-American populations with
      diabetes, for the first time exceeding the rate in their white European-American peers. One
      possible culprit is the increasing consumption of fructose which can lead to high blood fat
      levels. Fructose is a natural sugar found in fruits and table sugar but is also used the food
      industry as an ingredient and sweetener. Because fructose intakes are lower in the UK than in
      North America we are studying the effect of fructose intake in UK black West African and
      Caribbean people, to understand if fructose intake is indeed a reason for these ethnic
      differences.
    

Detailed description: 
      The overall nature of this study is to conduct an investigation into the metabolic effects of
      acute high fructose versus high glucose feeding in people of Black African (BA) compared to
      age and BMI-matched control subjects of White-European (WE) origin . The research question of
      our study is: do people of BA metabolise fructose differently than people of WE when
      challenged with a high sugar diet? Therefore, our specific aims are to determine the
      following in both people of BA and WE consuming both high fructose and high glucose meals: 1)
      the postprandial pattern of blood insulin, glucose, triglyceride and cholesterol
      concentrations; 2) ambulatory blood pressure measures during the postprandial period and 4)
      postprandial and 0-24-hour fasted serum and red blood cell membrane cholesterol and
      non-cholesterol sterol concentrations.

      Potential participants will attend the scheduled screening session where the requirements of
      participation will be described and the participants will be given an opportunity to ask any
      questions they may have. Those still willing to participate will sign the informed consent
      form before the screening assessment is performed. Screening will require a fasted blood
      sample to be taken as well as a brief questionnaire to ascertain ethnicity (self-declared),
      medications and health status. An assessment of weight, height and waist circumference will
      also be taken to confirm they meet the inclusion criteria. It is expected that the results of
      the screening blood sample will be available within 1-2 weeks. Those participants meeting the
      inclusion criteria will be contacted and scheduled for the first study visit. Those not
      meeting the criteria will be notified by their preferred means of contact, a copy of their
      results will be provided.

      Prior to attending participants treatment order will be randomized. Participants will report
      to the Metabolic Research Unit (MRU) at 08.00 following an overnight fast. A catheter will be
      inserted into an antecubital vein for collection of blood samples and a baseline blood sample
      collected at this time. Participant will be asked to undertake minimal physical activity
      during the remainder of the study period. A breakfast meal will be given at 0min, the lunch
      meal at 240min and meals will be consumed within 15 minutes. Participants will be fitted with
      a portable continuous blood pressure and heart rate monitor (arteriograph) and instructed on
      what to expect as it functions. Further blood samples will be taken at -30, -15, 0, 15, 30,
      45, 60, 90, 120, 180, 240, 300, 360, 420min and at 24hrs (1440min, fasted). The energy
      content of the meals will be the estimated energy requirements of the participant (to the
      nearest 100kcals), with 20% of total daily energy coming from glucose or fructose. The
      glucose or fructose will be given dissolved water with added colour and orange/fruit flavours
      and provided at breakfast, lunch and supper. The remaining daily caloric requirement for each
      participant will be given a standardized evening meal to take away and consume at home.
    

Intervention name(s): Dietary sugar
Intervention type(s): Dietary Supplement
Intervention description(s): This study examined the effect of high intakes of fructose compared to high intakes of glucose in a randomized crossover design. The treatment was in replacement of 20% of the daily caloric requirements for either fructose or glucose for each individual.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: Fructose; Insulin; Postprandial lipemia; Ambulatory blood pressure; Ethnicity