The Effect of Macronutrients in the Diet on Digestive and Cardiovascular Health
Condition: Obesity; Diabetes; Cardiovascular Diseases
MeSH terms: Cardiovascular Diseases
Study type: Interventional

Summary: 
      This study examined the effect of a 5-day HFD supplemented with specific fatty acids on
      gastrointestinal transit, appetite, food intake and substrate utilization. Another novel
      aspect of this chapter was examining whether a subsequent 5-day period was sufficient to
      reverse the effects of high-fat feeding on the aforementioned parameters.
    

Detailed description: 
      High-fat (HF) diets of as little as three days have been shown to accelerate GI transit. This
      study aimed to assess if 5-day HF supplemented diet varying in fatty acid composition were
      sufficient to accelerate GI transit, appetite responses and substrate utilisation and whether
      a 5-day deadaptation period to a HF diet would reverse the responses induced by adaptation to
      a HFD.

      The study will be conducted in a randomized, single-blinded manner in 24 healthy subjects.
      Three 5-day interventions will each followed by a test trial. In the first intervention
      period (CON), normal diet was supplemented with low-fat (LF) milkshakes (272 kcal, 6 g fat).
      The second and third interventions will involve repeating previous diet along with HF (1082
      kcal, 96 g fat) or LF milkshakes respectively. The three high-fat supplement groups that
      subjects will be randomized to are as follows: (1) olive oil (90 g oil), (2) olive oil + n-3
      EPA/DHA fish powder blend or (3) olive oil + macadamia oil blend.

      The effect of 5-day HF diet (daily milkshake supplement: 1082 kcal, 96 g fat) on gastric
      emptying and mouth to caecum transit time of a high-fat test will be measured using the 13C
      octanoic acid breath test and H2 inulin breath test respectively for six hours
      postprandially. During this time course, measurements of subjective appetite sensations by
      visual analogue scale and substrate utilization by indirect calorimetry were also collected.
      Subsequently, food intake will be measured using an ad libitum buffet meal.
    

Intervention name(s): Olive oil; Olive oil and fish powder; Olive oil and macadamia oil; Deadaptation
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Each volunteer will complete three test trials. The first (CONTROL) and second test trials (HF) were separated by 28 days. The third trial (LF) takes place on the 6th day following the second trial (5 days apart).
The CON and LF milkshake supplements are identical (272 kcal; 6 g fat). The basic control (CON) or LF milkshake (that the oil was added to) was: 275 g semi skimmed milk, 25 g chocolate milkshake mix, 15 g dried skimmed milk, 1 g xanthan gum. This was made up to 580 ml with still water.
High-fat milkshake supplements were consumed daily for five days before a test trial. 90 g olive oil added to the supplement for the purpose of the HF intervention phase.; Each volunteer will complete three test trials. The first (CONTROL) and second test trials (HF) were separated by 28 days. The third trial (LF) takes place on the 6th day following the second trial (5 days apart).
The CON and LF milkshake supplements are identical (272 kcal; 6 g fat). The basic control (CON) or LF milkshake (that the oil was added to) was: 275 g semi skimmed milk, 25 g chocolate milkshake mix, 15 g dried skimmed milk, 1 g xanthan gum. This was made up to 580 ml with still water.
High-fat milkshake supplements were consumed daily for five days before a test trial. 86.67 g olive oil and 3.3 g of n-3 fish powder (500 mg EPA+DHA)added to the supplement for the purpose of the HF intervention phase.; Each volunteer will complete three test trials. The first (CONTROL) and second test trials (HF) were separated by 28 days. The third trial (LF) takes place on the 6th day following the second trial (5 days apart).
The CON and LF milkshake supplements are identical (272 kcal; 6 g fat). The basic control (CON) or LF milkshake (that the oil was added to) was: 275 g semi skimmed milk, 25 g chocolate milkshake mix, 15 g dried skimmed milk, 1 g xanthan gum. This was made up to 580 ml with still water.
High-fat milkshake supplements were consumed daily for five days before a test trial. 74.82 g olive oil and 15.18 g macadamia nut oil added to the supplement for the purpose of the HF intervention phase.; A period of 5 days supplementation with the low-fat milkshake represents a de-adaptation period from high-fat intervention.
Other intervention name(s): OO; OF; OM; DEADAPT
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: Fats; Macronutrients; appetite; gastric emptying; Gastrointestinal transit